显示样式:     当前期刊: Gastroenterology    加入关注    导出
我的关注
我的收藏
您暂时未登录!
登录
  • Efficacy of Ledipasvir and Sofosbuvir Treatment of HCV Infection in Patients Coinfected with HBV
    Gastroenterology (IF 18.392) Pub Date : 2017-11-22
    Chun-Jen Liu, Wan-Long Chuang, I-Shyan Sheen, Horng-Yuan Wang, Chi-Yi Chen, Kuo-Chih Tseng, Ting-Tsung Chang, Benedetta Massetto, Jenny C. Yang, Chohee Yun, Steven J. Knox, Anu Osinusi, Gregory Camus, Deyuan Jiang, Diana M. Brainard, John G. McHutchison, Tsung-Hui Hu, You-Chun Hsu, Gin-Ho Lo, Chi-Jen Chu, Jyh-Jou Chen, Cheng-Yuan Peng, Ron-Nan Chien, Pei-Jer Chen

    Background & Aims There have been reports of reactivation of hepatitis B virus (HBV) infection during treatment of hepatitis C virus (HCV) infection with direct-acting antiviral agents. We performed a prospective study of risks and outcomes of HCV infection treatment with ledipasvir and sofosbuvir in patients with HBV infection. Methods We performed a phase 3b, multicenter, open-label study in Taiwan of 111 patients with HCV infection (61% HCV genotype 1, 39% HCV genotype 2 infection; 62% women, 16% with compensated cirrhosis) along with HBV infection. All but 1 were positive for the hepatitis B surface antigen (HBsAg); 1 patient who was HBsAg positive at screening was found to be HBsAg negative at baseline. Overall, 33% of participants had received prior treatment for HCV and 5% had previously been treated for HBV; no patient was on HBV therapy at the start of the study. All patients received a fixed-dose combination of 90 mg of the HCV NS5A inhibitor ledipasvir with 400 mg of the NS5B nucleotide analogue inhibitor sofosbuvir, once daily for 12 weeks. The primary endpoint was sustained virologic response (SVR) 12 weeks after the end of therapy. Results All 111 patients (100%) achieved an SVR. Of the 37 patients with baseline HBV DNA below 20 IU/mL, 31 (84%) had at least 1 episode of quantifiable HBV DNA through post-treatment week 12. Of the 74 patients with baseline HBV DNA levels of 20 IU/mL or more, 39 (53%) had increases of HBV DNA greater than 1 log10 IU/mL through post-treatment week 12. Overall, 5 patients had increased levels of HBV DNA concomitant with a level of alanine aminotransferase more than 2-fold the upper limit of normal though post-treatment Week 12. Of these, 3 patients started HBV treatment. In addition, one patient with HBV reactivation since Week 8 and concomitant ALT elevation > 2 x ULN at post treatment Week 48 started treatment at post treatment Week 53. This patient had clinical signs and symptoms associated with HBV reactivation. The most common adverse events were headache, upper respiratory infection, and fatigue. Conclusions In a prospective study, the combination of ledipasvir and sofosbuvir for 12 weeks produced an SVR in 100% of patients with HCV infection who were co-infected with HBV. Most patients had an increase in level of HBV DNA not associated with signs or symptoms. ClinicalTrials.gov no: NCT02613871

    更新日期:2017-11-23
  • Efficacy of Indigo naturalis in a Multicenter Randomized Controlled Trial of Patients with Ulcerative Colitis
    Gastroenterology (IF 18.392) Pub Date : 2017-11-22
    Makoto Naganuma, Shinya Sugimoto, Keiichi Mitsuyama, Taku Kobayashi, Naoki Yoshimura, Hidehisa Ohi, Shinji Tanaka, Akira Andoh, Naoki Ohmiya, Keiichiro Saigusa, Takayuki Yamamoto, Yuichi Morohoshi, Hitoshi Ichikawa, Katsuyoshi Matsuoka, Tadakazu Hisamatsu, Kenji Watanabe, Shinta Mizuno, Wataru Suda, Masahira Hattori, Shinji Fukuda, Akiyoshi Hirayama, Takayuki Abe, Mamoru Watanabe, Toshifumi Hibi, Yasuo Suzuki, Takanori Kanai

    Background & Aims Indigo naturalis (IN) is a traditional Chinese medicine that contains ligands for the aryl hydrocarbon receptor and promotes regeneration of the mucosa, by inducing production of interleukin 22. IN might induce mucosal healing in patients with ulcerative colitis (UC). We performed a randomized controlled trial to investigate the safety and efficacy of IN in patients with UC. Methods We performed a multicenter, double-blind trial evaluated the safety of 86 patients in Japan with active UC (Mayo scores of 6 or more), enrolled from March 30 through December 27 2016. Patients were randomly assigned to groups give a daily dose of 0.5, 1.0, or 2.0 g IN or placebo (1:1:1:1 ratio) for 8 weeks. The primary endpoint was the rate of clinical response at week 8, defined as a 3-point decrease in the Mayo score and a decrease of at least 30% from baseline, with a decrease of at least 1 point for the rectal bleeding subscore or absolute rectal bleeding score of 0–1. The main secondary endpoint was the rate of clinical remission at week 8, defined as a Mayo score or 2 or less and no subscores with a value greater than 1. Mucosal healing was also assessed at week 8. Results The trial was terminated due to an external reason: a report of a pulmonary arterial hypertension in a patient who used self-purchased IN for 6 months. In the intention to treat analysis, we observed a significant, dose-dependent linear trend in proportions of patients with clinical responses (13.6% with a clinical response to placebo; 69.6% to 0.5 g IN; 75.0% to 1.0 g IN; and 81.0% to 2.0 g IN) (Cochran-Armitage trend test P<.0001 compared with placebo). Proportions of patients in clinical remission at week 8 were significantly higher in the 1.0 g IN group (55.0%, P=.0004) and the 2.0 g IN group (38.1%, (P=.0093) than in the placebo group (4.5%). Proportions of patients with mucosal healing were 13.6% in the placebo group, 56.5% in the 0.5 g IN group, 60.0% in the 1.0 g IN group, and 47.6% in the 2.0 g IN group (P=.0278 compared to placebo). Although mild liver dysfunction was observed in 10 patients who received IN, no serious adverse events were observed. Conclusions In a randomized, placebo-controlled trial, we found 8 weeks of IN (0.5–2.0 g per day) to be effective in inducing a clinical response in patients with UC. However, IN should not be yet used because of the potential for adverse effects, including pulmonary arterial hypertension. Clinical Trials Registry no: UMIN000021439 (http://www.umin.ac.jp/ctr/)

    更新日期:2017-11-22
  • Computed Tomography Colonography vs Colonoscopy for Colorectal Cancer Surveillance After Surgery
    Gastroenterology (IF 18.392) Pub Date : 2017-11-22
    David S. Weinberg, Perry J. Pickhardt, David H. Bruining, Kristin Edwards, J.G. Fletcher, Marc J. Gollub, Eileen M. Keenan, Sonia S. Kupfer, Tianyu Li, Sam J. Lubner, Arnold J. Markowitz, Eric A. Ross

    Background & Aims Recommendations for surveillance after curative surgery for colorectal cancer (CRC) include a 1 year post-resection abdominal-pelvic computed tomography scan and optical colonoscopy (OC). CT colonography (CTC), when used in CRC screening, effectively identifies colorectal polyps ≥10 mm and cancers. We performed a prospective study to determine whether CTC, concurrent with CT, could substitute for OC in CRC surveillance. Methods Our study enrolled 231 patients with resected stage 0–III CRC, identified at 5 tertiary care academic centers. Approximately 1 year after surgery, participants underwent outpatient CTC plus CT, followed by same-day OC. CTC results were revealed after endoscopic visualization of sequential colonic segments, which were re-examined for discordant findings. The primary outcome was performance of CTC in detection of colorectal adenomas and cancers, using endoscopy as the reference standard. Results Of the 231 participants, 116 (50.2%) had polyps of any size or histology identified by OC, and 15.6% had conventional adenomas and/or serrated polyps ≥6 mm. No intra-luminal cancers were detected. CTC detected patients with polyps of ≥6 mm with 44.0% sensitivity (95% CI, 30.2–57.8) and 93.4% specificity (95% CI, 89.7–97.0). CTC detected polyps ≥10 mm with 76.9% sensitivity (95% CI 54.0–99.8) and 89.0% specificity (95% CI, 84.8–93.1). Similar values were found when only adenomatous polyps were considered. The negative predictive value of CTC for adenomas ≥6 mm was 90.7 (95% CI, 86.7–94.5) and for adenomas ≥10 mm the negative predictive value was 98.6 (95% CI, 97.0–100). Conclusions In a CRC surveillance population 1 year following resection, CTC was inferior to OC for detecting patients with polyps ≥6 mm. Clinical Trials.gov Registration Number: NCT02143115

    更新日期:2017-11-22
  • Factors Associated with Response to Teduglutide in Patients With Short-bowel Syndrome and Intestinal Failure
    Gastroenterology (IF 18.392) Pub Date : 2017-11-22
    Palle Bekker Jeppesen, Simon M. Gabe, Douglas L. Seidner, Hak-Myung Lee, Clément Olivier

    Background & Aims Clinical studies showed teduglutide to increase urine production and reduce need for parenteral support volume in patients with short bowel syndrome (SBS) with intestinal failure, increasing intestinal wet weight absorption and reducing diarrhea. However, the effects of teduglutide on parenteral support vary among patients. We performed a post-hoc analysis of a phase 3 placebo-controlled study to identify characteristics of patients in whom teduglutide has the largest effects on parenteral support volume response. Methods We collected data from 85 patients with SBS with intestinal failure, according to the European Society for Clinical Nutrition and Metabolism classification system, who received teduglutide or placebo between 25 November 2008 and 04 January 2011 at 27 sites in 10 countries. Changes in parenteral support volume were evaluated according to baseline parenteral support volume, bowel anatomy (group 1, jejunostomy/ileostomy; group 2, ≥50% colon in continuity without stoma; and group 3, other colon anatomies), and disease features (with inflammatory bowel disease, mesenteric vascular diseases, or other conditions). Correlation analyses were conducted using simple linear regression models, with unadjusted r2 values reported. Two-sided t tests were used for comparisons between treatment groups. Results We correlated parenteral support volume reduction with teduglutide treatment and baseline parenteral support volume (y = –0.3870x + 90.0279, r2=0.61; P<.0001). The effects of teduglutide on absolute parenteral support volume were significantly greater in group 1 patients (reduction of 919±644 mL/day)—not only compared with patients given placebo (reduction of 340±436 mL/day; P=.0112) but also compared with teduglutide-treated patients in group 2 (reduction of 355±306 mL/day; P=.0066). Teduglutide had an intermediate effect on patients in group 3. A minority of patients with SBS and inflammatory bowel diseases had colon in continuity (10.5% [n=2/19]), whereas most patients with SBS and vascular or other diseases had colon in continuity (84.4% [n=27/32] and 67.6% [n=23/34], respectively). Conclusions In a post-hoc analysis of data from a phase 3 study of the effects of teduglutide on patients with SBS, we associated reduced parenteral support volume with baseline parenteral support volume, bowel anatomy, and SBS features. These findings may inform initial parenteral support volume adjustments and management of these severely disabled patients. ClinicalTrials.gov no: NCT00798967; ClinicalTrialsRegister.eu no: 2008-006193-15

    更新日期:2017-11-22
  • Mouse Model of Alagille Syndrome and Mechanisms of Jagged1 Missense Mutations
    Gastroenterology (IF 18.392) Pub Date : 2017-11-21
    Emma R. Andersson, Indira V. Chivukula, Simona Hankeova, Marika Sjöqvist, Yat Long Tsoi, Daniel Ramsköld, Jan Masek, Aiman Elmansuri, Anita Hoogendoorn, Elenae Vazquez, Helena Storvall, Julie Netušilová, Meritxell Huch, Björn Fischler, Ewa Ellis, Adriana Contreras, Antal Nemeth, Kenneth C. Chien, Hans Clevers, Rickard Sandberg, Vitezslav Bryja, Urban Lendahl

    Background & Aims Alagille syndrome is a genetic disorder characterized by cholestasis, ocular abnormalities, characteristic facial features, heart defects, and vertebral malformations. Most cases are associated with mutations in JAGGED1 (JAG1), which encodes a Notch ligand, although it is not clear how these contribute to disease development. We aimed to develop a mouse model of Alagille syndrome to elucidate these mechanisms. Methods Mice with a missense mutation (H268Q) in Jag1 (Jag1+/Ndr mice) were outbred to a C3H/C57bl6 background to generate a mouse model for Alagille syndrome (Jag1Ndr/Ndr mice). Liver tissues were collected at different timepoints during development, analyzed by histology, and liver organoids were cultured and analyzed. We performed transcriptome analysis of Jag1Ndr/Ndr livers and livers from patients with Alagille syndrome, cross-referenced to the Human Protein Atlas, to identify commonly dysregulated pathways and biliary markers. We used species-specific transcriptome separation and ligand-receptor interaction assays to measure Notch signaling and the ability of JAG1Ndr to bind or activate Notch receptors. We studied signaling of JAG1 and JAG1Ndr via NOTCH 1, NOTCH2, and NOTCH3 and resulting gene expression patterns in parental and NOTCH1-expressing C2C12 cell lines. Results Jag1Ndr/Ndr mice had many features of Alagille syndrome, including eye, heart, and liver defects. Bile duct differentiation, morphogenesis, and function were dysregulated in newborn Jag1Ndr/Ndr mice, with aberrations in cholangiocyte polarity, but these defects improved in adult mice. Jag1Ndr/Ndr liver organoids collapsed in culture, indicating structural instability. Whole-transcriptome sequence analyses of liver tissues from mice and patients with Alagille syndrome identified dysregulated genes encoding proteins enriched at the apical side of cholangiocytes, including CFTR and SLC5A1, as well as reduced expression of IGF1. Exposure of Notch-expressing cells to JAG1Ndr, compared with JAG1, led to hypomorphic Notch signaling, based on transcriptome analysis. JAG1-expressing cells, but not JAG1Ndr-expressing cells, bound soluble Notch1 extracellular domain, quantified by flow cytometry. However, JAG1 and JAG1Ndr cells each bound NOTCH2, and signaling from NOTCH2 signaling was reduced but not completely inhibited, in response to JAG1Ndr compared to JAG1. Conclusions In mice, expression of a missense mutant of Jag1 (Jag1Ndr) disrupts bile duct development and recapitulates Alagille syndrome phenotypes in heart, eye and craniofacial dysmorphology. JAG1Ndr does not bind NOTCH1, but binds NOTCH2, and elicits hypomorphic signaling. This mouse model can be used to study other features of Alagille syndrome and organ development.

    更新日期:2017-11-21
  • Combination of Gene Expression Signature and Model for End-stage Liver Disease Score Predicts Survival of Patients With Severe Alcoholic Hepatitis
    Gastroenterology (IF 18.392) Pub Date : 2017-11-20
    Eric Trépo, Nicolas Goossens, Naoto Fujiwara, Won-Min Song, Antonio Colaprico, Astrid Marot, Laurent Spahr, Pieter Demetter, Christine Sempoux, Gene Y. Im, Joan Saldarriaga, Thierry Gustot, Jacques Devière, Swan N. Thung, Charlotte Minsart, Thomas Sersté, Gianluca Bontempi, Karim Abdelrahman, Jean Henrion, Delphine Degré, Valerio Lucidi, Laura Rubbia-Brandt, Venugopalan D. Nair, Christophe Moreno, Pierre Deltenre, Yujin Hoshida, Denis Franchimont

    Background & Aims Patients with severe alcoholic hepatitis (AH) have a high risk of death within 90 days. Corticosteroids, which can cause severe adverse events, are the only treatment that increases short-term survival. It is a challenge to predict outcomes of patients with severe AH. Therefore, we developed a scoring system to predict patient survival, integrating baseline molecular and clinical variables. Methods We obtained fixed liver biopsy samples from 71 consecutive patients diagnosed with severe AH and treated with corticosteroids from July 2006 through December 2013 in Brussels, Belgium (derivation cohort). Gene expression patterns were analyzed by microarrays and clinical data were collected for 180 days. We identified gene expression signatures and clinical data that associated with survival without liver transplantation at 90 and 180 days after initiation of corticosteroid therapy. Findings were validated using liver biopsies from 48 consecutive patients with severe AH treated with corticosteroids, collected from March 2010 through February 2015 at hospitals in Belgium and Switzerland (validation cohort 1) and in liver biopsies from 20 patients (9 received corticosteroid treatment), collected from January 2012 through May 2015 in the United States (validation cohort 2). Results We integrated data on expression patterns of 123 genes and model for end-stage liver disease (MELD) scores to assign patients to groups with poor survival (29% survived 90 days and 26% survived 180 days) and good survival (76% survived 90 days and 65% survived 180 days) (P<.001) in the derivation cohort. We named this assignment system the gene signature-MELD (gs-MELD) score. In the validation cohort 1, the gs-MELD score discriminated patients with a poor survival (43% survived 90 days) from those with a good survival (96% survived 90 days) (P<.001). The gs-MELD score also discriminated between patients with a poor survival at 180 days (34% survived) and a good survival at 180 days (84% survived) (P<.001). The time-dependent area under the receiver operator characteristic curve for the score was 0.86 (95% CI, 0.73–0.99) for survival at 90 days, and 0.83 (95% CI, 0.71–0.96) for survival at 180 days. This score outperformed other clinical models to predict survival of patients with severe AH in validation cohort 1. In validation cohort 2, the gs-MELD discriminated patients with a poor survival at 90 days (12% survived) from those with a poor survival at 90 days (100%) (P<.001). Conclusions We integrated data on baseline liver gene expression pattern and MELD score to create the gs-MELD scoring system, which identifies patients with severe AH, treated or not with corticosteroids, the gs-MELD score, most and least likely to survive for 90 and 180 days.

    更新日期:2017-11-20
  • Prevalence of Microsatellite Instability in Intraductal Papillary Mucinous Neoplasms of the Pancreas
    Gastroenterology (IF 18.392) Pub Date : 2017-11-20
    R.M. Lupinacci, A. Goloudina, O. Buhard, J.B. Bachet, R. Maréchal, P. Demetter, J. Cros, A. Bardier-Dupas, A. Collura, P. Cervera, A. Scriva, S. Dumont, P. Hammel, A. Sauvanet, C. Louvet, J.-R. Delpéro, F. Paye, J.-C. Vaillant, T. André, J. Closset, J.-F. Emile, J.-L. Van Laethem, V. Jonchère, I. Abd Alsamad, M. Antoine, A. Rodenas, J.F. Fléjou, N. Dusetti, J. Iovanna, A. Duval, M. Svrcek

    Microsatellite instability (MSI) due to mismatch repair deficiency (dMMR) is detected in a small proportion of pancreatic ductal adenocarcinomas (PDACs). dMMR and MSI have been associated with responses of metastatic tumors, including PDACs, to immune checkpoint inhibitor therapy. We performed immunohistochemical analyses of a 445 PDAC specimens, collected from consecutive patients at multiple centers, to identify those with dMMR, based on loss of mismatch repair proteins MLH1, MSH2, MSH6, and/or PMS2. We detected dMMR in 1.6% of tumor samples; we found dMMR in a larger proportion of intraductal papillary mucinous neoplasms (IPMN)-related tumors (4/58, 6.9%) than non-IPMN PDAC (5/385, 1.3%) (P=.02). PDACs with dMMR contained potentially immunogenic mutations due to MSI in coding repeat sequences. PDACs with dMMR or MSI had a higher density of CD8+ T cells at the invasive front than PDACs without dMMR or MSI (P=.08; Fisher exact test). A higher proportion of PDACs with dMMR or MSI expressed the CD274 molecule (PD-L1, 8/9) than PDACs without dMMR or MSI (4/10) (P=.05). Times of disease-free survival and overall survival did not differ significantly between patients with PDACs with dMMR or MSI vs without dMMR or MSI. Studies are needed to determine whether these features of PDACs with dMMR or MSI might serve as prognostic factors.

    更新日期:2017-11-20
  • Association Between Coffee Intake After Diagnosis of Colorectal Cancer and Reduced mortality
    Gastroenterology (IF 18.392) Pub Date : 2017-11-20
    Yang Hu, Ming Ding, Chen Yuan, Kana Wu, Stephanie A. Smith-Warner, Frank B. Hu, Andrew T. Chan, Jeffrey A. Meyerhardt, Shuji Ogino, Charles S. Fuchs, Edward L. Giovannucci, Mingyang Song

    Background & Aims Few studies have examined the association between coffee intake and survival after diagnosis of colorectal cancer (CRC). We performed a prospective study to investigate the association between coffee intake after a diagnosis of CRC and mortality. Methods We collected data from the Nurses’ Health Study (1984–2012) and Health Professionals Follow-up Study (1986–2012), following 1599 patients diagnosed with stage 1 or 2 CRC. CRC was reported on questionnaires and ascertained by review of medical records and pathology reports; intake of food and beverages was determined from responses to semi-quantitative food frequency questionnaires. Participants were asked how often during the previous year that they consumed coffee, with 1 cup as the standard portion size. The first questionnaire response collected at least 6 months but not more than 4 years after diagnosis was used for assessment of post-diagnostic intake (median time from diagnosis to the dietary assessment, 2.2 years). The last sFFQ prior to diagnosis was used to assess pre-diagnostic dietary intake. Results During a median of 7.8 years of follow-up, we documented 803 deaths, of which 188 were due to CRC. In the multivariable adjusted models, compared with nondrinkers, patients who consumed at least 4 cups of coffee per day had a 52% lower risk of CRC-specific death (hazard ratio [HR] 0.48; 95% CI, 0.28–0.83; P for trend=.003) and 30% reduced risk of all-cause death (HR, 0.70; 95% CI, 0.54–0.91; P for trend <.001). High intake of caffeinated and decaffeinated coffee (2 or more cups/day) was associated with lower risk of CRC-specific mortality and all-cause mortality. When coffee intake before vs after CRC diagnosis were examined, compared with patients consistently consuming low amounts (less than 2 cups/day), those who maintained a high intake (2 or more cups/day) had a significantly lower risk of CRC-specific death (multivariable HR, 0.63; 95% CI, 0.44–0.89) and death from any cause (multivariable HR, 0.71; 95% CI, 0.60–0.85). Conclusions In an analysis data from the Nurses’ Health Study and Health Professionals Follow-up Study, we associated intake of caffeinated and decaffeinated coffee after diagnosis of CRC with lower risk of CRC-specific death and overall death. Studies are needed to determine the mechanisms by which coffee might reduce CRC progression.

    更新日期:2017-11-20
  • Prognostic Utility of Total 68Ga-DOTATATE-Avid Tumor Volume in Patients with Neuroendocrine Tumors
    Gastroenterology (IF 18.392) Pub Date : 2017-11-16
    Amit Tirosh, Georgios Z. Papadakis, Corina Millo, Dima Hammoud, Samira M. Sadowski, Peter Herscovitch, Karel Pacak, Stephen J. Marx, Lily Yang, Pavel Nockel, Jasmine Shell, Patience Green, Xavier M. Keutgen, Dhaval Patel, Naris Nilubol, Electron Kebebew

    Background & Aims Survival times vary among patients with neuroendocrine tumors (NETs)—even among those with the same site, stage, and grade of primary tumor. This makes it difficult to select treatment for patients with unresectable NETs, because some patients can survive decades without treatment. 68Gallium-DOTATATE positron emission tomography with computed tomography (68Ga-DOTATATE PET/CT) is a sensitive imaging technique for detection of NETs. We investigated the prognostic accuracy of 68Ga-DOTATATE PET/CT analysis of tumor volume in patients with NETs. Methods We performed a prospective study of 184 patients with NETs (128 [69.6%] with metastases and 11 patients [6.0%] with locally advanced disease) at the National Institutes of Health Clinical Center from 2013 through 2017. All patients underwent 68Ga-DOTATATE PET/CT image analysis and total 68Ga-DOTATATE-Avid tumor volume (68Ga-DOTATATE TV) was determined. We also measured fasting serum chromogranin A, neuron-specific enolase, gastrin, glucagon, vasoactive intestinal peptide, pancreatic polypeptide, and 24-hour urinary 5-hydroxyindoleacetic acid levels in all patients. Disease progression was defined as a new lesion or a growth of a known lesion, during the interval between baseline 68Ga-DOTATATE PET/CT scan and follow-up imaging (14.0±6.1 months; range 1–35 months). The primary outcomes were progression-free survival (PFS) and disease-specific mortality during a median follow-up time of 18 months (range 4–35 months). Results We found an inverse correlation between quartiles of 68Ga-DOTATATE TV and PFS (P=.001) and disease-specific survival (P=.002). A 68Ga-DOTATATE TV of 7.0 mL or more was associated with higher odds of disease progression (hazard ratio, 3.0; P=.04). A 68Ga-DOTATATE TV of 35.8 mL or more was associated with increased risk of disease-specific death (hazard ratio, 10.6) in multivariable analysis (P=.01), as well as in subgroup analysis of patients with pancreatic NETs. Conclusions In a prospective study, we demonstrated the prognostic utility of 68Ga-DOTATATE TV in a large cohort of patients with NETs, in terms of PFS and disease-specific mortality.

    更新日期:2017-11-20
  • Germline Genetic Features of Young Individuals with Colorectal Cancer
    Gastroenterology (IF 18.392) Pub Date : 2017-11-14
    Elena M. Stoffel, Erika Koeppe, Jessica Everett, Peter Ulintz, Mark Kiel, Jenae Osborne, Linford Williams, Kristen Hanson, Stephen B. Gruber, Laura S. Rozek

    Background & AimsThe incidence of colorectal cancer (CRC) in individuals younger than 50 years old is increasing. We sought to ascertain the proportion of young CRC cases associated with genetic predisposition.MethodsWe performed a retrospective study of individuals diagnosed with CRC at an age younger than 50 years, evaluated by the clinical genetics service at a single tertiary care cancer center from 1998 through 2015. We collected data on patient histories, tumor phenotypes, and results of germline DNA sequencing. For subjects with uninformative clinical evaluations, germline DNA samples were (re)sequenced using a research-based next-generation sequencing multigene panel. The primary outcome was identification of a pathogenic germline mutation associated with cancer predisposition.ResultsOf 430 young CRC cases, 111 (26%) had a first-degree relative with CRC. Forty-one of the subjects with CRC (10%) had tumors with histologic evidence for mismatch repair deficiency. Of 315 subjects who underwent clinical germline sequencing, 79 had mutations associated with a hereditary cancer syndrome and 21 had variants of uncertain significance. Fifty-six subjects had pathogenic variants associated with Lynch syndrome (25 with mutations in MSH2, 24 with mutations in MLH1, 5 with mutations in MSH6, and 2 with mutations in PMS2) and 10 subjects had pathogenic variants associated with familial adenomatous polyposis. Thirteen subjects had mutations in other cancer-associated genes (8 in MUTYH, 2 in SMAD4, 1 in BRCA1, 1 in TP53, and 1 in CHEK2), all identified through multigene panel tests. Among 117 patients with uninformative clinical evaluations, next-generation sequence analysis using a multigene panel detected actionable germline variants in 6 patients (5%). Only 43 of the 85 subjects with germline mutations associated with a hereditary cancer syndrome (51%) reported a CRC diagnosis in a first-degree relative.ConclusionsApproximately 1 in 5 individuals diagnosed with CRC at age younger than 50 years carries a germline mutation associated with cancer; nearly half of these do not have clinical histories typically associated with the identified syndrome. Germline testing with multigene cancer panels should be considered for all young patients with CRC.

    更新日期:2017-11-14
  • Factors That Contribute to Differences in Survival of Black vs White Patients With Colorectal Cancer
    Gastroenterology (IF 18.392) Pub Date : 2017-11-14
    Helmneh M. Sineshaw, Kimmie Ng, W. Dana Flanders, Otis W. Brawley, Ahmedin Jemal

    Background & AimsPrevious studies reported that black vs white disparities in survival among elderly patients with colorectal cancer (CRC) were due to differences in tumor characteristics (tumor stage, grade, nodal status, and comorbidity) rather than differences in treatment. We sought to determine the sequential contribution of differences in insurance, comorbidity, tumor characteristics, and treatment receipt to the black-white survival disparity among patients with CRC in 18–64 years old.MethodsWe used data from the National Cancer Database, a hospital-based cancer registry database sponsored by the American College of Surgeons and the American Cancer Society, on non-Hispanic black (black) and non-Hispanic white (white) patients, 18–64 years old, diagnosed from 2004 through 2012 with single or first primary invasive stage I–IV CRC. Blacks were sequentially matched by demographics, insurance, comorbidity, tumor characteristics, and treatment with 5 white partially overlapping subgroups using propensity score and greedy matching algorithm. We used the Kaplan-Meier method to estimate 5-year survival, and Cox proportional hazards models to generate hazard ratios (HR).ResultsThe absolute 5-year survival difference between black and white unmatched patients with CRC was 9.2% (57.3% for black patients vs 66.5% for white patients; P < .0001). The absolute difference in survival did not change after patient groups were matched for demographics, but decreased to 4.9% (47% relative decrease [4.3% of 9.2%]) when they were matched for insurance and to 2.3% when they were matched for tumor characteristics (26% relative decrease [2.4% of 9.2%]). Further matching by treatment did not reduce the difference in 5-year survival between black and white patients. In proportional hazards model, insurance and tumor characteristics matching accounted for the 54% and 27% excess risk of death in black patients, respectively.ConclusionsIn an analysis of data from the National Cancer Database, we found that insurance coverage differences accounted for approximately one-half of the disparity in survival rate between black vs white patients with CRC in 18–64 years old; tumor characteristics accounted for a quarter of the disparity. Affordable health insurance coverage for all populations could substantially reduce differences in survival times of black vs white patients with CRC.

    更新日期:2017-11-14
  • HLA-DQ–Gluten Tetramer Blood Test Accurately Identifies Patients With and Without Celiac Disease in Absence of Gluten Consumption
    Gastroenterology (IF 18.392) Pub Date : 2017-11-14
    Vikas K. Sarna, Knut E.A. Lundin, Lars Mørkrid, Shuo-Wang Qiao, Ludvig M. Sollid, Asbjørn Christophersen

    Background & AimsCeliac disease is characterized by HLA-DQ2/8-restricted responses of CD4+ T cells to cereal gluten proteins. A diagnosis of celiac disease based on serologic and histologic evidence and duodenal histology requires patients to be on gluten-containing diets. The growing number of individuals adhering to a gluten-free diet (GFD) without exclusion of celiac disease complicates its detection. HLA-DQ–gluten tetramers can be used to detect gluten-specific T cells in blood of patients with celiac disease, even if they are on a GFD. We investigated whether an HLA-DQ–gluten tetramer-based assay accurately identifies patients with celiac disease.MethodsWe produced HLA-DQ–gluten tetramers and added them to peripheral blood mononuclear cells isolated from 143 HLA-DQ2.5+ subjects (62 subjects with celiac disease on a GFD, 19 subjects without celiac disease on a GFD [due to self-reported gluten-sensitivity], 10 subjects with celiac disease on a gluten-containing diet, and 52 presumed healthy individuals [controls]). T cells that bound HLA-DQ–gluten tetramers were quantified by flow cytometry. Laboratory tests and flow cytometry gating analyses were performed by researchers blinded to sample type, except for samples from subjects with celiac disease on a gluten-containing diet. Test precision analyses were performed using samples from 10 subjects.ResultsFor the HLA-DQ–gluten tetramer-based assay, we combined flow-cytometry variables in a multiple regression model that identified individuals with celiac disease on a GFD with an area under the receiver operating characteristic curve (AUROC) value of 0.96 (95% CI, 0.89–1.00) vs subjects without celiac disease on a GFD. The assay detected individuals with celiac disease on a gluten-containing diet vs controls with an AUROC value of 0.95 (95% CI, 0.90–1.00). Optimized cut-off values identified subjects with celiac disease on a GFD with 97% sensitivity (95% CI, 0.92–1.00) and 95% specificity (95% CI, 0.84–1.00), vs subjects without celiac disease on a GFD. The values identified subjects with celiac disease on a gluten-containing diet with 100% sensitivity (95% CI, 1.00–1.00]) and 90% specificity (95% CI, 0.83–0.98) vs controls. In an analysis of 4 controls with positive results from the HLA-DQ–gluten tetramer test, 2 had unrecognized celiac disease and the remaining 2 had T cells that proliferated in response to gluten antigen in vitro.ConclusionsAn HLA-DQ–gluten tetramer-based assays that detects gluten-reactive T cells identifies patients with and without celiac disease with a high level of accuracy, regardless of whether the individuals are on a GFD. This test would allow individuals with suspected celiac disease to avoid gluten challenge and duodenal biopsy, but requires validation in a larger study. Clinicaltrials.gov no: NCT02442219

    更新日期:2017-11-14
  • Patterns of Resistance-associated Substitutions in Patients With Chronic HCV Infection Following Treatment with Direct-acting Antivirals
    Gastroenterology (IF 18.392) Pub Date : 2017-11-13
    Julia Dietz, Simone Susser, Johannes Vermehren, Kai-Henrik Peiffer, Georgios Grammatikos, Annemarie Berger, Peter Ferenci, Maria Buti, Beat Müllhaupt, Bela Hunyady, Holger Hinrichsen, Stefan Mauss, Jörg Petersen, Peter Buggisch, Gisela Felten, Dietrich Hüppe, Gaby Knecht, Thomas Lutz, Eckart Schott, Christoph Berg, Ulrich Spengler, Thomas von Hahn, Thomas Berg, Stefan Zeuzem, Christoph Sarrazin

    Background & AimsLittle is known about substitutions that mediate resistance of HCV to direct-acting antivirals (DAAs), due to the small number of patients with treatment failure in approval studies. It is important to identify resistance patterns to select effective salvage treatments.MethodsWe performed a comprehensive analysis for resistance-associated substitutions (RASs) in HCV genes (NS3, NS5A, NS5B) targeted by DAAs. We compared NS3, NS5A, and NS5B sequences from 626 patients in Europe with DAA failure with sequences from 2322 DAA-naïve patients, infected with HCV genotypes 1–4. We considered RASs to be relevant if they were associated with DAA failure in patients or conferred a greater than 2-fold changed in susceptibility compared with a reference strain in in vitro replicon assays. Data were collected on pretreatment status, DAA regimen, the treatment initiation date and duration, and virologic response. Patients who received at least 4 weeks antiviral treatment were included in the analysis.ResultsRASs in NS3 associated with simeprevir or paritaprevir failure include R155K and D168E/V. In addition, several RASs were specifically associated with failure of simeprevir (Q80K/R in patients with genotype 1a or 4) or paritaprevir (Y56H in combination with D168V in patients with genotype 1b). Y93H in NS5A was the RAS most frequently associated with failure of daclatasvir, ledipasvir, or ombitasvir in patients with genotype 1b infection, and L31M was associated with failure of daclatasvir or ledipasvir, but not ombitasvir. RASs in NS5A were heterogeneous among patients with HCV genotype 1a or genotype 4 infections.In patients with HCV genotype 3, Y93H was associated with resistance to daclatasvir, but no RASs were associated with ledipasvir failure, pointing to a limited efficacy of ledipasvir in patients with genotype 3. Among patients failed by sofosbuvir-containing regimens, L159F was enriched in patients with genotype 1b (together with C316N) or genotype 3 infection, whereas the RAS S282T was rarely observed.ConclusionsWe compared RASs in NS3, NS5A, and NS5B among patients failed by DAA therapy. Theses varied with the HCV genotype and subtype, and the different drug classes. These findings might be used to select salvage therapies.

    更新日期:2017-11-14
  • Enteric Delivery of Regenerating Family Member 3 alpha Alters the Intestinal Microbiota and Controls Inflammation in Mice With Colitis
    Gastroenterology (IF 18.392) Pub Date : 2017-11-11
    Marion Darnaud, Alexandre Dos Santos, Patrick Gonzalez, Sandrine Augui, Claire Lacoste, Christophe Desterke, Gert De Hertogh, Emma Valentino, Emilie Braun, Jinzi Zheng, Raphael Boisgard, Christel Neut, Laurent Dubuquoy, Franck Chiappini, Didier Samuel, Patricia Lepage, Francesca Guerrieri, Joel Doré, Christian Bréchot, Nicolas Moniaux, Jamila Faivre

    Background & Aims Paneth cell dysfunction causes deficiencies in intestinal C-type lectins and antimicrobial peptides, which leads to dysbiosis of the intestinal microbiota, alters the mucosal barrier, and promotes development of inflammatory bowel diseases. We investigated whether transgenic expression of the human regenerating family member 3 alpha gene (REG3A) alters the fecal microbiota and affects development of colitis in mice. Methods We performed studies with C57BL/6 mice that express human regenerating family member 3 alpha (hREG3A) in hepatocytes, via the albumin gene promoter. In these mice, hREG3A travels via the bile to the intestinal lumen. Some mice were given dextran sodium sulphate (DSS) to induce colitis. Feces were collected from mice and the composition of the microbiota was analyzed by 16S rRNA sequencing. The fecal microbiome was also analyzed from mice that express only 1 copy of human REG3A transgene but were fed feces from control mice (not expressing hREG3A) as newborns. Mice expressing hREG3A were monitored for DSS-induced colitis after cohousing or feeding feces from control mice. Colitis was induced in another set of control and hREG3A transgenic mice by administration of trinitrobenzene sulfonic acid; some mice were given intrarectal injections of the hREG3A protein. Colon tissues were collected from mice and analyzed by histology and immunohistochemistry to detect mucin 2, as well as by 16S rRNA fluorescence in situ hybridization, transcriptional analyses, and quantitative PCR. We measured levels of reactive oxygen species (ROS) in bacterial cultures and fecal microbiota using H2-DCFDA and flow cytometry. Results The fecal microbiota of mice that express hREG3A had a significant shift in composition, compared to control mice, with enrichment of Clostridiales (Ruminococcaceae, Lachnospiraceae) and depletion of Bacteroidetes (Prevotellaceae); the transgenic mice developed less-severe colitis following administration of DSS than control mice, associated with preserved gut barrier integrity and reduced bacterial translocation, epithelial inflammation, and oxidative damage. A similar shift in the composition of the fecal microbiota occurred after a few months in transgenic mice heterozygous for REG3A that harbored a wild-type maternal microbiota at birth; these mice developed less-severe forms of colitis following DSS administration. Cohoused and germ-free mice fed feces from REG3A transgenic mice and given DSS developed less-severe forms of colitis and had reduced lipopolysaccharide activation of the toll-like receptor 4 and increased survival times compared to mice not fed feces from REG3A transgenic mice. REG3A transgenic mice developed only mild colonic inflammation after exposure to trinitrobenzene sulfonic acid (TNBS), compared to control mice. Control mice given intrarectal hREG3A and exposed to TNBS showed less colon damage and inflammation than mice not given intrarectal hREG3A. Fecal samples from REG3A transgenic mice had lower levels of ROS than feces from control mice during DSS administration. Addition of hREG3A to bacterial cultures reduced levels of ROS and increased survival of oxygen-sensitive commensal bacteria (Faecalibacterium prausnitzii and Roseburia intestinalis). Conclusions Mice with hepatocytes that express human REG3A, which travels to the intestinal lumen, are less sensitive to colitis than control mice. We found hREG3A to alter the colonic microbiota by decreasing levels of ROS. Fecal microbiota from REG3A transgenic mice protect non-transgenic mice from induction of colitis. These findings indicate a role for reduction of oxidative stress in preserving the gut microbiota and its ability to prevent inflammation.

    更新日期:2017-11-11
  • Population Health Management for Inflammatory Bowel Disease
    Gastroenterology (IF 18.392) Pub Date : 2017-11-07
    Parambir S. Dulai, Siddharth Singh, Lucilla Ohno-Machado, William J. Sandborn

    Inflammatory bowel diseases (IBD) are chronic and impose significant, multi-dimensional burdens on patients and healthcare systems. The increasing prevalence of IBD will only worsen this problem globally—population health management (PHM) strategies are needed to increase quality of care and population health outcomes while reducing healthcare costs. We discuss the key components of PHM in IBD. Effective implementation of PHM strategies requires accurate identification of at-risk patients and of key areas of variability in care. Improving outcomes of the at-risk population requires implementation of a multi-component chronic care model designed to shift delivery of ambulatory care from acute, episodic, and reactive encounters, to proactive, planned, long-term care. This is achieved through team care of an activated patient with the help of remote monitoring, clinical information systems and integrated decision support, with accompanying changes in delivery systems. Performance measurement is integral to any PHM strategy. This involves developing and implementing meaningful metrics of different phases of quality of IBD care and measuring them efficiently using modern clinical information systems. Such an integrated framework of PHM in IBD will facilitate the delivery of high-value care to patients.

    更新日期:2017-11-10
  • No Increase in Risk of Acute Myocardial Infarction in Privately Insured Adults Prescribed Proton Pump Inhibitors vs Histamine-2 Receptor Antagonists (2002–2014)
    Gastroenterology (IF 18.392) Pub Date : 2017-11-06
    Suzanne N. Landi, Robert S. Sandler, Virginia Pate, Jennifer L. Lund

    Background & AimsProton pump inhibitors (PPIs) are commonly used medications. Recent studies reported an increased risk of acute myocardial infarction (MI) in PPI users vs non-users. We evaluated MI risk associated with PPIs compared with histamine-2 receptor antagonists (H2RAs) in privately insured adults in the United States.MethodsUsing administrative claims from commercial and Medicare Supplemental plans (2001–2014), we compared risk of MI in patients who started a new prescription for PPIs vs H2RAs. Enrollees were followed from their first prescription until MI, medication discontinuation, plan disenrollment, or December 31, 2014. MI was defined using hospital diagnosis codes. Risk differences (RD), risk ratios, and 95% CIs were estimated using Kaplan-Meier methods at 3,12, and 36 months after treatment initiation. Standardized morbidity ratio weights were used to control measured confounding. Analyses were stratified by plan type (commercial vs Medicare Supplemental).ResultsWe identified more than 5 million new users of prescription PPIs and H2RAs. Median follow-up time was 60 days for patients with commercial insurance and 96 days in patients with Medicare Supplemental insurance. The 12-month weighted risk of MI was low overall (approximately 2 cases per 1000 among patients in commercial plans; 8 per 1000 among patients in Medicare Supplemental plans). In the RD analysis, we found no significant differences in MI risk between patients who started PPIs vs H2RAs for the first 12 months, either in the commercial population (weighted RD per 1000, –0.08; 95% CI, –0.51 to 0.36) or the Medicare Supplemental population (weighted RD per 1000, –0.45; 95% CI, –1.53 to 0.58).ConclusionIn an analysis of administrative claims from commercial and Medicare Supplemental plans, we found no evidence that prescription PPIs increase risk of MI compared to prescription H2RAs. Physicians and patients should not avoid starting a PPI because of concerns related to MI risk.

    更新日期:2017-11-10
  • Low-dose Aspirin Use Does Not Increase Survival in 2 Independent Population-based Cohorts of Patients With Esophageal or Gastric Cancer
    Gastroenterology (IF 18.392) Pub Date : 2017-11-06
    Andrew D. Spence, John Busby, Brian T. Johnston, John A. Baron, Carmel M. Hughes, Helen G. Coleman, Chris R. Cardwell

    Background & AimsPre-clinical studies have shown aspirin to have anti-cancer properties and epidemiologic studies have associated aspirin use with longer survival times of patients with cancer. We studied 2 large cohorts to determine the association between aspirin use and cancer-specific mortality in patients with esophageal or gastric cancer.MethodsWe performed a population-based study using cohorts of patients newly diagnosed with esophageal or gastric cancer, identified from cancer registries in England from 1998 through 2012 and the Scottish Cancer Registry from 2009 through 2012. Low-dose aspirin prescriptions were identified from linkages to the United Kingdom Clinical Research Practice Datalink in England and the Prescribing Information System in Scotland. Deaths were identified from linkage to national mortality records, with follow up until September 2015 in England and January 2015 in Scotland. Time-dependent Cox regression models were used to calculate hazard ratios (HR) and 95% CIs for cancer-specific mortality by low-dose aspirin use after adjusting for potential confounders. Meta-analysis was used to pool results across the two cohorts.ResultsThe combined English and Scottish cohorts contained 4654 esophageal cancer and 3833 gastric cancer patients including 3240 and 2392 cancer-specific deaths, respectively. The proportions surviving 1 year, based upon cancer-specific mortality, were similar in aspirin users vs non-users after diagnosis with esophageal cancer (48% vs 50% in England and 49% vs 46% in Scotland, respectively) or gastric cancer (58% vs 57% in England and 59% vs 55% in Scotland, respectively). There was no association between post-diagnosis use of low-dose aspirin and cancer-specific mortality among patients with esophageal cancer (pooled adjusted HR, 0.98; 95% CI, 0.89–1.09) or gastric cancer (pooled adjusted HR, 0.96, 95% CI, 0.85–1.08). Long-term aspirin use was not associated with cancer-specific mortality after diagnosis of esophageal cancer (pooled adjusted HR, 1.03; 95% CI, 0.85–1.25) or gastric cancer (pooled adjusted HR, 1.06; 95% CI, 0.85–1.32).ConclusionsIn analyses of 2 large independent cohorts in the United Kingdom, low-dose aspirin usage was not associated with increased survival of patients diagnosed with esophageal or gastric cancer.

    更新日期:2017-11-10
  • MIR21 drives resistance to Heat Shock Protein 90 inhibition in cholangiocarcinoma
    Gastroenterology (IF 18.392) Pub Date : 2017-11-04
    Andrea Lampis, Pietro Carotenuto, Georgios Vlachogiannis, Luciano Cascione, Somaieh Hedayat, Rosemary Burke, Paul Clarke, Else Bosma, Michele Simbolo, Aldo Scarpa, Sijia Yu, Rebecca Cole, Elizabeth Smyth, Javier Fernández Mateos, Ruwaida Begum, Blanka Hezelova, Zakaria Eltahir, Andrew Wotherspoon, Nicos Fotiadis, Maria Antonietta Bali, Chirag Nepal, Khurum Khan, Mark Stubbs, Jens C. Hahne, Pierluigi Gasparini, Vincenza Guzzardo, Carlo M. Croce, Suzanne Eccles, Matteo Fassan, David Cunningham, Jesper B. Andersen, Paul Workman, Nicola Valeri, Chiara Braconi

    Background & AimsCholangiocarcinomas (CCA) are resistant to chemotherapy, so new therapeutic agents are needed. We performed a screen to identify small molecule compounds that are active against CCAs. Levels of microRNA 21 (MIR21 or miRNA21) are increased in CCAs. We investigated whether miRNA21 mediates resistance of CCA cells and organoids to HSP90 inhibitors.MethodsWe performed a high-throughput screen of 484 small molecule compounds to identify those that reduced viability of 6 human CCA cell lines. We tested the effects of HSP90 inhibitors on cells with disruption of the MIR21 gene, cells incubated with MIR21 inhibitors, and stable cell lines with inducible expression of MIR21. We obtained CCA biopsies from patients, cultured them as organoids (patient-derived organoids, PDOs). We assessed their architecture, mutation and gene expression patterns, response to compounds in culture, and when grown as subcutaneous xenograft tumors in mice.ResultsCells with IDH1 and PBRM1 mutations had the highest level of sensitivity to histone deacetylase inhibitors. HSP90 inhibitors were effective in all cell lines, irrespective of mutations. Sensitivity of cells to HSP90 inhibitors correlated inversely with baseline level of MIR21. Disruption of MIR21 increased cell sensitivity to HSP90 inhibitors. CCA cells that expressed transgenic MIR21 were more resistant to HSP90 inhibitors than cells transfected with control vectors; inactivation of MIR21 in these cells restored sensitivity to these agents. MIR21 was shown to target the DnaJ heatshockprotein family (Hsp40) member B5 (DNAJB5). Transgenic expression of DNAJB5 in CCA cells that overexpressed MIR21 re-sensitized them to HSP90 inhibitors. Sensitivity of PDOs to HSP90 inhibitors, in culture and when grown as xenograft tumors in mice, depended on expression of miRNA21.Conclusions: miRNA21 appears to mediate resistance of CCA cells to HSP90 inhibitors by reducing levels of DNAJB5. HSP90 inhibitors might be developed for treatment of CCA and miRNA21 might be a marker of sensitivity to these agents.

    更新日期:2017-11-10
  • Historical Perspectives and Advances in the Mesenchymal Stem Cell Research for the Treatment of Liver Diseases
    Gastroenterology (IF 18.392) Pub Date : 2017-10-26
    Chien-Wei Lee, Yu-Fan Chen, Hao-Hsiang Wu, Oscar K. Lee

    Liver transplantation is the only effective therapy for patients with decompensated cirrhosis and fulminant liver failure. However, due to a shortage of donor livers and complications associated with immune suppression, there is an urgent need for new therapeutic strategies for patients with end-stage liver diseases. Given their unique function in self-renewal and differentiation potential, stem cells might be used to regenerate damaged liver tissue. Recent studies have shown that stem cell-based therapies can improve liver function in a mouse model of hepatic failure. Moreover, acellular liver scaffolds, seeded with hepatocytes, produced functional bioengineered livers for organ transplantation in pre-clinical studies. The therapeutic potential of stem cells or their differentiated progenies will depend on their capacity to differentiate into mature and functional cell types after transplantation. It will also be important to devise methods to overcome their genomic instability, immune reactivity, and tumorigenic potential. We review directions and advances in the use of mesenchymal stem cells and their derived hepatocytes for liver regeneration. We also discuss the potential applications of hepatocytes derived from human pluripotent stem cells and challenges to using these cells in treating end-stage liver disease.

    更新日期:2017-10-27
  • Efficacy of NVR 3-778, Alone and in Combination With Pegylated Interferon, vs Entecavir in uPA/SCID Mice With Humanized Livers and HBV Infection
    Gastroenterology (IF 18.392) Pub Date : 2017-10-24
    Klaus Klumpp, Takashi Shimada, Lena Allweiss, Tassilo Volz, Marc Lütgehetmann, G. Hartman, Osvaldo A. Flores, Angela M. Lam, Maura Dandri

    Background & Aims NVR3-778 is a capsid assembly modulator in clinical development. We determined the in vivo anti-viral efficacy and effects on innate and endoplasmic reticulum (ER) stress responses of NVR3-778 alone or in combination with pegylated interferon alpha (peg-IFN) and compared with entecavir. Methods We performed 2 studies, with a total of 61 uPA/SCID mice with humanized livers. Mice were infected with a HBV genotype C preparation; we waited 8 weeks for persistent infection of the human hepatocytes in livers of mice. Mice were then randomly assigned to groups (5 or 6 per group) given vehicle (control), NVR3-778, entecavir, peg-IFN, NVR3-778 + entecavir, or NVR3-778 + peg-IFN for 6 weeks. We measured levels of HB surface antigen (HBsAg), HB e antigen (HBeAg), HBV RNA, alanine aminotransferase (ALT), and human serum albumin at different time points. Livers were collected and analyzed by immunohistochemistry; levels of HBV DNA, covalently closed circular DNA (cccDNA), and HBV RNA, along with markers of ER stress and IFN response, were quantified. Results Mice given NVR3-778 or entecavir alone for 6 weeks had reduced serum levels of HBV DNA compared with controls or mice given peg-IFN. The largest reduction was observed in mice given NVR3-778 + peg-IFN—in all mice in this group the serum level of HBV DNA was below the limit of quantification. NVR3-778 and peg-IFN, but not entecavir, also reduced serum level of HBV RNA. The largest effect was obtained in the NVR3-778 + peg-IFN group, in which serum level of HBV RNA was below the limit of quantification. Levels of HBsAg and HBeAg were reduced significantly in only the groups that received peg-IFN. Levels of cccDNA did not differ significantly among groups. NVR3-778 was not associated with any significant changes in level of ALT, the ER stress response, or interferon-stimulated genes. Conclusions NVR3-778 has high antiviral activity in mice with humanized livers and stable HBV infection, reducing levels of serum HBV DNA and HBV RNA. Entecavir reduced levels of serum HBV DNA, but had no effect on HBV RNA. The combination of NVR3-778 and peg-IFN prevented viral replication and HBV RNA particle production to a greater extent than each compound alone or entecavir.

    更新日期:2017-10-25
  • Exome-Wide Association Study Of Pancreatic Cancer Risk
    Gastroenterology (IF 18.392) Pub Date : 2017-10-24
    Robert C. Grant, Robert E. Denroche, Ayelet Borgida, Carl Virtanen, Natalie Cook, Alyssa L. Smith, Ashton A. Connor, Julie M. Wilson, Gloria Peterson, Nicholas J. Roberts, Alison P. Klein, Sean M. Grimmond, Andrew Biankin, Sean Cleary, Malcolm Moore, Mathieu Lemire, George Zogopolous, Lincoln Stein, Steven Gallinger

    We conducted a case–control exome-wide association study to discover germline variants in coding regions that affect risk for pancreatic cancer, combining data from 5 studies. We analyzed exome and genome sequencing data from 437 patients with pancreatic cancer (cases) and 1922 individuals not known to have cancer (controls). In the primary analysis, BRCA2 had the strongest enrichment for rare inactivating variants (17/437 cases vs 3/1922 controls) (P=3.27x10–6; exome-wide statistical significance threshold P<2.5x10–6). Cases had more rare inactivating variants in DNA repair genes than controls, even after excluding 13 genes known to predispose to pancreatic cancer (adjusted odds ratio, 1.35, P=.045). At the suggestive threshold (P<.001), 6 genes were enriched for rare damaging variants (UHMK1, AP1G2, DNTA, CHST6, FGFR3, and EPHA1) and 7 genes had associations with pancreatic cancer risk, based on the sequence-kernel association test. We confirmed variants in BRCA2 as the most common high-penetrant genetic factor associated with pancreatic cancer and we also identified candidate pancreatic cancer genes. Large collaborations and novel approaches are needed to overcome the genetic heterogeneity of pancreatic cancer predisposition.

    更新日期:2017-10-24
  • Cost-effectiveness of Access Expansion to Treatment of Hepatitis C Virus Infection Through Primary Care Providers
    Gastroenterology (IF 18.392) Pub Date : 2017-10-23
    Thilo Rattay, P. Dumont, Hauke S. Heinzow, David W. Hutton

    Background & Aims Chronic hepatitis C virus (HCV) infection is a major burden on individuals and health care systems. The Extension for Community Healthcare Outcomes (Project ECHO) enables primary care providers to deliver best-practice care for complex conditions to underserved populations. The United States Congress passed the ECHO Act in late 2016, requiring the Department of Health and Human Services to investigate the model. We performed a cost-effectiveness analysis to assess diagnosis and treatment of HCV infection in a primary care patient panel with and without the implementation of Project ECHO. Methods We used Markov models to simulate disease progression, quality of life, and life expectancy among individuals with HCV infection and for the general population. Data from the University of New Mexico's ECHO operation for HCV show an increase in treatment rates. Corresponding increases in survival, quality-adjusted life years (QALYs), costs, and resulting budget impact between ECHO and non-ECHO HCV patients were then compared. Results Project ECHO increased costs and QALYs. The incremental cost-effectiveness ratio of ECHO was $10,351 per quality-adjusted life year compared to the status quo; >99.9% of iterations fell below the willingness-to-pay threshold of $100,000 per QALY. We were unable to confirm whether the increase in rates of treatment associated with Project ECHO were due to increased or more targeted screening, higher adherence or access to treatment. Our sensitivity analyses show that the results are largely independent of the cause. Budget impact analysis shows payers would have to invest an additional $339.54 million over a 5-year period to increase treatment by 4,446 patients, per 1 million covered lives. Conclusion Using a simulated primary care patient panel, we showed that Project ECHO is a cost-effective way to find and treat patients with HCV infection at scale using existing primary care providers. This approach could substantially reduce the burden of chronic HCV infection in the United States, but high budgetary costs suggest that incremental rollout of ECHO may be best.

    更新日期:2017-10-24
  • Mitochondrial dysfunction, through impaired autophagy, leads to endoplasmic reticulum stress, deregulated lipid metabolism, and pancreatitis in animal models
    Gastroenterology (IF 18.392) Pub Date : 2017-10-23
    Gyorgy Biczo, Eszter T. Vegh, Natalia Shalbueva, Olga A. Mareninova, Jason Elperin, Ethan Lotshaw, Sophie Gretler, Aurelia Lugea, Sudarshan R. Malla, David Dawson, Piotr Ruchala, Julian Whitelegge, Samuel W. French, Li Wen, Sohail Z. Husain, Fred S. Gorelick, Peter Hegyi, Zoltan Rakonczay Jr., Ilya Gukovsky, Anna S. Gukovskaya.

    Background & Aims Little is known about the signaling pathways that initiate and promote acute pancreatitis (AP). The pathogenesis of AP has been associated with abnormal increases in cytosolic Ca2+, mitochondrial dysfunction, impaired autophagy, and endoplasmic reticulum (ER) stress. We analyzed the mechanisms of these dysfunctions and their relationships, and how these contribute to development of AP in mice and rats. Methods Pancreatitis was induced in C57BL/6J mice (control) and mice deficient in peptidylprolyl isomerase D (cyclophilin D, encoded by Ppid) by administration of L-arginine (also in rats), caerulein, bile acid, or an AP-inducing diet. Parameters of pancreatitis, mitochondrial function, autophagy, ER stress, and lipid metabolism were measured in pancreatic tissue, acinar cells, and isolated mitochondria. Some mice with AP were given trehalose to enhance autophagic efficiency. Human pancreatitis tissues were analyzed by immunofluorescence. Results Mitochondrial dysfunction in pancreas of mice with AP was induced by either mitochondrial Ca2+ overload or through a Ca2+ overload-independent pathway that involved reduced activity of F-ATP synthase (80% inhibition in pancreatic mitochondria isolated from rats or mice given L-arginine). Both pathways were mediated by cyclophilin D and led to mitochondrial depolarization and fragmentation. Mitochondrial dysfunction caused pancreatic ER stress, impaired autophagy, and deregulation of lipid metabolism. These pathologic responses were abrogated in cyclophilin D-knockout mice. Administration of trehalose largely prevented trypsinogen activation, necrosis, and other parameters of pancreatic injury in mice with L-arginine AP. Tissues from patients with pancreatitis had markers of mitochondrial damage and impaired autophagy, compared with normal pancreas. Conclusions In different animal models, we find a central role for mitochondrial dysfunction, and for impaired autophagy as its principal downstream effector, in development of AP. In particular, the pathway involving enhanced interaction of cyclophilin D with F-ATP synthase mediates L-arginine induced pancreatitis, a model of severe AP the pathogenesis of which has remained unknown. Strategies to restore mitochondrial and/or autophagic function might be developed for treatment of AP.

    更新日期:2017-10-23
  • Genome and Methylome Variation in Helicobacter pylori With a cag Pathogenicity Island During Early Stages of Human Infection
    Gastroenterology (IF 18.392) Pub Date : 2017-10-21
    Sandra Nell, Iratxe Estibariz, Juliane Krebes, Boyke Bunk, David Y. Graham, Jörg Overmann, Yi Song, Cathrin Spröer, Ines Yang, Thomas Wex, Jonas Korlach, Peter Malfertheiner, Sebastian Suerbaum

    Background & Aims Helicobacter pylori is remarkable for its genetic variation. Yet little isknown about its genetic changes during early stages of human infection, as the bacteria adapt to their new environment. We analyzed genome and methylome variations in a fully virulent strain of H pylori strain during experimental infection. Methods We performed a randomized Phase 1 and 2, observer-blind, placebo-controlled, study of 12 healthy, H pylori-negative adults in Germany from October 2008 through March 2010. The volunteers were given a prophylactic vaccine candidate (n=7) or placebo (n=5) and then challenged with H pylori strain BCM-300. Biopsy samples were collected and H pylori were isolated. Genomes of the challenge strain and 12 re-isolates, obtained 12 weeks after (or in 1 case, 62 weeks after) infection were sequenced by single-molecule, real-time technology, which, in parallel, permitted determination of genome-wide methylation patterns for all strains. Functional effects of genetic changes observed in H pylori strains during human infection were assessed by measuring release of interleukin 8 from AGS cells (to detect cag PAI function), neutral red uptake (to detect vacuolating cytotoxin activity), and adhesion assays. Results The observed mutation rate was in agreement with rates previously determined from patients with chronic H pylori infections, without evidence of a mutation burst. A loss; of cag PAI function was observed in 3 re-isolates. In addition, 3 re-isolates from the vaccine; group acquired mutations in the vacuolating cytotoxin gene vacA, resulting in loss of; vacuolization activity from gastric epithelial cells. We observed inter-strain variation in; methylomes due to phase variation in genes encoding methyltransferases. Conclusions We analyzed adaptation of a fully virulent strain of H pylori to 12 differentvolunteers to obtain a robust estimate of the frequency of genetic and epigenetic changes inthe absence of inter-strain recombination. Our findings indicate that the large amount of; genetic variation in H pylori poses a challenge to vaccine development. ClinicalTrials.gov no: NCT00736476.

    更新日期:2017-10-23
  • Accurate Classification of Diminutive Colorectal Polyps Using Computer-aided Analysis
    Gastroenterology (IF 18.392) Pub Date : 2017-10-16
    Peng-Jen Chen, Meng-Chiung Lin, Mei-Ju Lai, Jung-Chun Lin, Henry Horng-Shing Lu, Vincent S. Tseng

    Background & Aims Narrow-band imaging (NBI) is an image-enhanced form of endoscopy used to observed microstructures and capillaries of the mucosal epithelium that allows for real-time prediction of histologic features of colorectal polyps. However, NBI expertise is required to differentiate hyperplastic from neoplastic polyps with high levels of accuracy. We developed and tested a system of computer-aided diagnosis with a deep neural network (DNN-CAD) to analyze narrow-band images of diminutive colorectal polyps. Methods We collected 1476 images of neoplastic polyps and 681 images of hyperplastic polyps, obtained from the picture archiving and communications system database in a tertiary hospital in Taiwan. Histologic findings from the polyps were also collected and used as the reference standard. The images and data were used to train the DNN. A test set of images (96 hyperplastic and 188 neoplastic polyps, smaller than 5 mm), obtained from patients who underwent colonoscopies from March 2017 through August 2017, was then used to test the diagnostic ability of the DNN-CAD vs endoscopists (2 expert and 4 novice), who were asked to classify the images of the test set as neoplastic or hyperplastic. Their classifications were compared with findings from histologic analysis. The primary outcome measures were diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic time. The accuracy, sensitivity, specificity, PPV, NPV, and diagnostic time were compared among DNN-CAD, the novice endoscopists, and the expert endoscopists. The study was designed to detect a difference of 10% in accuracy by a 2-sided McNemar test. Results In the test set, the DNN-CAD identified neoplastic or hyperplastic polyps with 96.3% sensitivity, 78.1% specificity, a PPV of 89.6%, and a NPV of 91.5%. Fewer than half of the novice endoscopists classified polyps with a NPV of 90% (their NPVs ranged from 73.9% to 84.0%). DNN-CAD classified polyps as neoplastic or hyperplastic in 0.45±0.07 sec—shorter than the time required by experts (1.54±1.30 sec) and nonexperts (1.77±1.37 sec) (both P<.001). DNN-CAD classified polyps with perfect intra-observer agreement (kappa score of 1). There was a low level of intra-observer and inter-observer agreement in classification among endoscopists. Conclusions We developed a system called DNN-CAD to identify neoplastic or hyperplastic colorectal polyps less than 5 mm; it classified polyps with a PPV of 89.6%, and a NPV of 91.5%, and in a shorter time than endoscopists. This deep-learning model has potential for not only endoscopic image recognition but for other forms of medical image analysis, including sonography, computed tomography, and magnetic resonance images.

    更新日期:2017-10-16
  • Long Noncoding RNA uc.173 Promotes Renewal of the Intestinal Mucosa by Inducing Degradation of MicroRNA 195
    Gastroenterology (IF 18.392) Pub Date : 2017-10-16
    Lan Xiao, Jing Wu, Jun-Yao Wang, Hee Kyoung Chung, Sudhakar Kalakonda, Jaladanki N. Rao, Myriam Gorospe, Jian-Ying Wang

    Background and Aim s: The mammalian intestinal epithelium self renews rapidly and homeostasis is preserved via tightly controlled mechanisms. Long noncoding RNAs transcribed from ultraconserved regions (T-UCRs) control different cell functions, but little is known about their role in maintaining the integrity of the intestinal epithelium. We searched for T-UCRs that regulate growth of the intestinal mucosa and investigated the mechanism by which T-UCR uc.173 regulates epithelial renewal. Methods C57BL/6J mice were deprived of food for 48 hrs in fasting experiments. Some mice were given intraperitoneal injections of a plasmid encoding LNA-anti-uc.173, to knock down endogenous uc.173. For studies using organoids, primary enterocytes were isolated from the intestine and transfected with the uc.173 transgene to increase uc.173 levels. Intestinal epithelial cells (Caco-2 and IEC-6 lines) were transfected with LNA-anti-uc.173 or uc.173 transgene. We quantified intestinal epithelial renewal based on BrdU incorporation, villus height and crypt depth, and cell number. The association of uc.173 with microRNA 195 (miRNA195) was determined by RNA pull-down assays. Results Genome-wide profile analyses identified 21 T-UCRs, including uc.173, that were differentially expressed between intestinal mucosa of fasted vs non-fasted mice. Increasing levels of uc.173 by expression of a transgene increased growth of intestinal epithelial cells and organoids. Decreasing uc.173 levels by LNA-anti-uc.173 in mice reduced renewal of the intestinal epithelium. We found that uc.173 interacted directly with the primary transcript of miRNA195, leading to miRNA195 degradation. Conclusions In analyses of intestinal epithelial cells and mice, we identified uc.173 noncoding RNA that regulates growth of the intestinal mucosa and stimulates intestinal epithelial renewal by reducing levels of miRNA195.

    更新日期:2017-10-16
  • Management of Patients With Adenocarcinoma or Squamous Cancer of The Esophagus
    Gastroenterology (IF 18.392) Pub Date : 2017-10-14
    David H. Ilson, Richard Hillegersberg

    Esophageal cancer is characterized by the early and frequent metastasis. Surgery is the primary treatment for early-stage disease, whereas patients with patients with locally advanced disease receive peri-operative chemotherapy or chemoradiotherapy. Squamous cancers can be treated with primary chemoradiotherapy without surgery, depending on their response to therapy and patient tolerance for subsequent surgery. Chemotherapy with a fluorinated pyrimidine and a platinum agent, followed by later treatment with taxanes and irinotecan, provides some benefit. Agents that inhibit the erb-b2 receptor tyrosine kinase 2 (ERBB2 or HER2), or vascular endothelial growth factor (VEGF), including trastuzumab, ramucirumab, and apatinib, increase response and survival times. Esophageal adenocarcinomas have mutations in tumor protein p53 and mutations that activate receptor-associated tyrosine kinase, VEGF, and cell cycle pathways, whereas esophageal squamous tumors have a distinct set of mutations. Esophageal cancers develop systems to evade anti-tumor immune responses, but studies are needed to determine how immune checkpoint modification contributes to esophageal tumor development.

    更新日期:2017-10-14
  • Insights into the Pathophysiology of Esophageal Adenocarcinoma
    Gastroenterology (IF 18.392) Pub Date : 2017-10-14
    Michael Quante, Trevor A. Graham, Marnix Jansen

    Although researchers have identified genetic alterations that contribute to development of esophageal adenocarcinoma, we know little about features of patients or environmental factors that mediate progression of chronic acid biliary reflux to Barrett’s esophagus and cancer. Increasing our understanding of the mechanisms by which normal squamous epithelium progresses to early-stage invasive cancer will help formulate rational surveillance guidelines and allow us to divest resources away from patients at low risk of malignancy. We review the cellular and genetic alterations that occur during progression of Barrett’s esophagus, based on findings from clinical studies and mouse models of disease. We review the features of the luminal and mucosal microenvironment of Barrett’s esophagus that promote, in a small proportion of patients, development of esophageal adenocarcinoma. Markers of clonal evolution might be used to determine patient risk for cancer and set surveillance intervals.

    更新日期:2017-10-14
  • Pathophysiology of Gastroesophageal Reflux Disease
    Gastroenterology (IF 18.392) Pub Date : 2017-10-14
    Jan Tack, John E. Pandolfino

    The pathogenesis of gastroesophageal reflux disease (GERD) is complex and involves changes in reflux exposure, epithelial resistance, and visceral sensitivity. The gastric refluxate is a noxious material that injures the esophagus and elicits symptoms. Esophageal exposure to gastric refluxate is the primary determinant of disease severity. This exposure arises via compromise of the anti-reflux barrier and reduced ability of the esophagus to clear and buffer the refluxate, leading to reflux disease. However, complications and symptoms also occur in the context of normal reflux burden, when there is either poor epithelial resistance or increased visceral sensitivity. Reflux therefore develops via alterations in the balance of aggressive and defensive forces.

    更新日期:2017-10-14
  • Transcription and Signaling Regulators in Developing Neuronal Subtypes of Mouse and Human Enteric Nervous System
    Gastroenterology (IF 18.392) Pub Date : 2017-10-12
    Fatima Memic, Viktoria Knoflach, Khomgrit Morarach, Rebecca Sadler, Catia Laranjeira, Jens Hjerling-Leffler, Erik Sundström, Vassilis Pachnis, Ulrika Marklund

    Background and Aims The enteric nervous system (ENS) regulates gastrointestinal function via different subtypes of neurons, organized into fine-tuned neural circuits. It is not clear how cell diversity is created within the embryonic ENS—information required for development of cell-based therapies and models of enteric neuropathies. We aimed to identify proteins that regulate ENS differentiation and network formation. Methods We generated and compared RNA expression profiles of the entire ENS, ENS progenitor cells, and non-ENS gut cells of mice, collected at embryonic days 11.5 and 15.5, when different subtypes of neurons are formed. Gastrointestinal tissues from R26ReYFP reporter mice crossed to Sox10-CreERT2 or Wnt1-Cre mice were dissected and the 6 populations of cells were isolated by flow cytometry. We used histochemistry to map differentially expressed proteins in mouse and human gut tissues at different stages of development, in different regions. We examined enteric neuronal diversity and gastric function in Wnt1-Cre x Sox6fl/fl mice, which do not express the Sox6 gene in the ENS. Results We identified 147 transcription and signaling factors that varied in spatial and temporal expression during development of the mouse ENS. Of the factors also analyzed in human ENS, most were conserved. We uncovered 16 signaling pathways (such as FGF and Eph/ephrin pathways). Transcription factors were grouped according to their specific expression in enteric progenitor cells (such as MEF2C), enteric neurons (such as SOX4) or neuron subpopulations (such as SATB1 and SOX6). Lack of SOX6 in the ENS reduced the numbers of gastric dopamine neurons and delayed gastric emptying. Conclusions Using transcriptome and histochemical analyses of the developing mouse and human ENS, we mapped expression patterns of transcription and signaling factors. Further studies of these candidate determinants might elucidate the mechanisms by which enteric stem cells differentiate into neuronal subtypes and form distinct connectivity patterns during ENS development. We found expression of SOX6 to be required for development of gastric dopamine neurons.

    更新日期:2017-10-12
  • DNA Methylation and Transcription Patterns in Intestinal Epithelial Cells From Pediatric Patients With Inflammatory Bowel Diseases Differentiate Disease Subtypes and Associate With Outcome
    Gastroenterology (IF 18.392) Pub Date : 2017-10-12
    K.J. Howell, J. Kraiczy, K.M. Nayak, M. Gasparetto, A. Ross, C. Lee, T.N. Mak, B.-K. Koo, N. Kumar, T. Lawley, A. Sinha, P. Rosenstiel, R. Heuschkel, O. Stegle, M. Zilbauer

    Background & Aims We analyzed DNA methylation patterns and transcriptomes of primary intestinal epithelial cells (IEC) of children newly diagnosed with inflammatory bowel diseases (IBD) to learn more about pathogenesis. Methods We obtained mucosal biopsies (n=236) collected from terminal ileum and ascending and sigmoid colons of children (median age=13) newly diagnosed with IBD (43 with Crohn’s disease [CD], 23 with ulcerative colitis [UC]), and 30 children without IBD (controls). Patients were recruited and managed at a hospital in the United Kingdom from 2013 through 2016. We also obtained biopsies collected at later stages from a subset of patients. IECs were purified and analyzed for genome-wide DNA methylation patterns and gene expression profiles. Adjacent microbiota were isolated from biopsies and analyzed by 16S gene sequencing. We generated intestinal organoid cultures from a subset of samples and genome-wide DNA methylation analysis was performed. Results We found gut segment-specific differences in DNA methylation and transcription profiles of IECs from children with IBD vs controls; some were independent of mucosal inflammation. Changes in gut microbiota between IBD and control groups were not as large, and were difficult to assess due large amounts of intra-individual variation. Only IECs from patients with CD had changes in DNA methylation and transcription patterns in terminal ileum epithelium, compared with controls. Colon epithelium from patients with CD and from patients with UC had distinct changes in DNA methylation and transcription patterns, compared with controls. In IECs from patients with IBD, changes in DNA methylation, compared with controls, were stable over time and were partially retained in ex-vivo organoid cultures. Statistical analyses of epithelial cell profiles allowed us to distinguish children with CD or UC from controls; profiles correlated with disease outcome parameters, such as the requirement for treatment with biologic agents. Conclusions We identified specific changes in DNA methylation and transcriptome patterns in IECs from pediatric patients with IBD compared to controls. These data indicate that IECs undergo changes during IBD development and could be involved in pathogenesis. Further analyses of primary IECs from patients with IBD could improve our understanding of the large variations in disease progression and outcomes.

    更新日期:2017-10-12
  • MicroRNAs 15A and 16-1 Activate Signaling Pathways That Mediate Chemotaxis of Immune Regulatory B cells to Colorectal Tumors
    Gastroenterology (IF 18.392) Pub Date : 2017-10-12
    Ronghua Liu, Zhou Lu, Jie Gu, Jiajing Liu, Enyu Huang, Xiaoming Liu, Luman Wang, Jiao Yang, Yuting Deng, Jiawen Qian, Feifei Luo, Zhiming Wang, Hushan Zhang, Xuechao Jiang, Dan Zhang, Jing Qian, Guangwei Liu, Hongguang Zhu, Youcun Qian, Zhanju Liu, Yiwei Chu

    Background & Aims B cells infiltrate tumors but little is known about how they affect tumor growth and progression. microRNA15A (MIR15A or miRNA15A) and microRNA16-1 (MIR16-1 or miRNA16-1) regulate cell proliferation, apoptosis and drug resistance. We investigated their involvement in B cell–mediated immune suppression by colorectal tumors. Methods Mice with disruptions of the gene cluster that encodes MIR15A and MIR16-1 (KO mice), and control (C57BL/B6) mice were given azoxymethane with dextran sodium sulfate (AD) to induce formation of colorectal tumors. Mice were given anti-CD20 to delete B cells, or injections of agomir to increase MIR15A and MIR16-1. Proliferation of CD8+T cells was measured by carboxyfluorescein-succinimidyl-ester analysis. Colon tissues were collected form mice and analyzed by flow cytometry, microRNA sequencing, and for cytokine production. Intestinal epithelial cells (IECs) were isolated and transfected with microRNA mimics, to identify their targets. We analyzed miRNA expression patterns and quantified B cells in colorectal cancer tissue microarrays derived from 90 patients who underwent surgical resection, from July 2006 through April 2008, in Shanghai, China; expression data was compared with clinical outcomes. Results Tumors that developed in KO mice following administration of AD were larger and contained greater numbers of B cells than tumors than grew in control mice. Most of the B cells in the tumors were positive for immunoglobulin A (IgA+). IgA+B cells expressed high levels of immune-regulatory molecules (PD-L1, interleukin 10 [IL10], and TGFB), and repressed the proliferation and activation of CD8+T cells. Levels of MIR15A and MIR16-1 were reduced in colon tumors from mice, compared with non-tumor colon tissue. Incubation of IECs with IL17A reduced expression of MIR15A and MIR16-1. Transgenic expression of MIR15A and MIR16-1 in IECs decreased activation of NF-κB and STAT1 by reducing expression of I-kappaB kinases; this resulted in reduced production of CXCL9 and CXCL10 and decreased chemotaxis of IgA+B cells. Tumors in mice injected with AD and agomir grew more slowly than tumors in mice not given in agomir and contained fewer IgA+B cells. We found a negative correlation between levels of MIR15A and MIR16-1 and numbers of IgA+B cells in human colorectal tumor tissues; high levels of MIR15A and MIR16-1 and low numbers of IgA+B cells associated with longer survival times of patients. Conclusions We found increased levels of MIR15A and MIR16-1 to reduce numbers of IgA+B cells in colorectal tumor tissues and correlate with increased survival time of patients. In mice that lack MIR15A and MIR16-1, colon tumors grow more rapidly and contain increased numbers of IgA+B cells. MIR15A and MIR16-1 appear to activate signaling pathways required for B cell–mediated immune suppression.

    更新日期:2017-10-12
  • Low Rates of Gastrointestinal and non-Gastrointestinal Complications for Screening or Surveillance Colonoscopies in a Population-based Study
    Gastroenterology (IF 18.392) Pub Date : 2017-10-12
    Wang Louise, Mannalithara Ajitha, Singh Gurkirpal, Ladabaum Uri

    Background The full spectrum of serious non-gastrointestinal (non-GI) post-colonoscopy complications has not been well characterized. We analyzed rates of and factors associated with adverse post-colonoscopy GI and non-GI events (cardiovascular, pulmonary, or infectious) attributable to screening or surveillance colonoscopy (S-colo) and non-screening or non-surveillance colonoscopy (NS-colo). Methods We performed a population-based study of colonoscopy complications using databases from California hospital-owned and nonhospital-owned ambulatory facilities, emergency departments, and hospitals from January 1, 2005 through December 31, 2011. We identified patients who underwent S-colo (1.58 million), NS-colo (1.22 million), or low-risk comparator procedures (joint injection, aspiration, lithotripsy; arthroscopy, carpal tunnel, or cataract; 2.02 million) in California’s Ambulatory Services Databases. We identified patients who developed adverse events within 30 days, and factors associated with these events, through patient-level linkage to California’s Emergency Department and Inpatient Databases. Results After S-colo, the numbers of lower GI bleeding, perforation, myocardial infarction, and ischemic stroke per 10,000-persons were 5.3 (95% CI, 4.8–5.9), 2.9 (95% CI, 2.5–3.3), 2.5 (95% CI, 2.1–2.9), and 4.7 (95%CI, 4.1–5.2) without biopsy or intervention; with biopsy or intervention, numbers per 10,000-persons were 36.4 (95% CI, 35.1–37.6), 6.3 (95% CI, 5.8–6.8), 4.2 (95% CI, 3.8–4.7), and 9.1 (95% CI, 8.5–9.7). Rates of dysrhythmia were higher. After NS-colo, event rates were substantially higher. Most serious complications led to hospitalization, and most GI complications occurred within 14 days of colonoscopy. Ranges of adjusted odds ratios for serious GI complications, myocardial infarction, ischemic stroke, and serious pulmonary events after S-colo vs comparator procedures were 2.18 (95% CI, 2.02–2.36) to 5.13 (95% CI, 4.81–5.47), 0.67 (95% CI, 0.56–0.81) to 0.99 (95% CI, 0.83–1.19), 0.66 (95% CI, 0.59–0.75) to 1.13 (95% CI, 0.99–1.29), and 0.64 (95% CI, 0.61–0.68) to 1.05 (95% CI, 0.98–1.11). Biopsy or intervention, comorbidity, Black race, low income, public insurance, and NS-colo were associated with post-colonoscopy adverse events. Conclusions In a population-based study in California, we found that following S-colo, rates of serious GI adverse events were low but clinically relevant, and that rates of myocardial infarction, stroke, and serious pulmonary events were no higher than after low-risk comparator procedures. Rates of myocardial infarction are similar, but rates of stroke are higher, than those reported for the general population.

    更新日期:2017-10-12
  • Clinical Practice Update: The Use of Per-Oral Endoscopic Myotomy in Achalasia: Expert Review and Best Practice Advice From the American Gastroenterological Association
    Gastroenterology (IF 18.392) Pub Date : 2017-10-06
    Peter J. Kahrilas, David Katzka, Joel E. Richter

    The purpose of this review is to describe a place for per-oral endoscopic myotomy (POEM) among the currently available robust treatments for achalasia.The recommendations outlined in this review are based on expert opinion and on relevant publications from PubMed and EMbase. The Clinical Practice Updates Committee of the American Gastroenterological Association proposes the following recommendations: 1) in determining the need for achalasia therapy, patient-specific parameters (Chicago Classification subtype, comorbidities, early vs late disease, primary or secondary causes) should be considered along with published efficacy data; 2) given the complexity of this procedure, POEM should be performed by experienced physicians in high-volume centers because an estimated 20−40 procedures are needed to achieve competence; 3) if the expertise is available, POEM should be considered as primary therapy for type III achalasia; 4) if the expertise is available, POEM should be considered as treatment option comparable with laparoscopic Heller myotomy for any of the achalasia syndromes; and 5) post-POEM patients should be considered high risk to develop reflux esophagitis and advised of the management considerations (potential indefinite proton pump inhibitor therapy and/or surveillance endoscopy) of this before undergoing the procedure.

    更新日期:2017-10-06
  • Interleukin 35 Expression Correlates with Microvessel Density in Pancreatic Ductal Adenocarcinoma, Recruits Monocytes, and Promotes Growth and Angiogenesis of Xenograft Tumors in Mice
    Gastroenterology (IF 18.392) Pub Date : 2017-10-06
    Chongbiao Huang, Zengxun Li, Na Li, Yang Li, Antao Chang, Tiansuo Zhao, Xiuchao Wang, Hongwei Wang, Song Gao, Shengyu Yang, Jihui Hao, He Ren

    Background & Aims Cells of the monocyte lineage contribute to tumor angiogenesis. Interleukin 35 (IL35) is a member of the IL12 family produced by regulatory, but not effector, T cells. IL35 is a dimer comprising the IL12 alpha and IL27 beta chains, encoded by IL12A and EBI3, respectively. Expression of IL35 is increased in pancreatic ductal adenocarcinomas (PDACs) compared with normal pancreatic tissues, and promotes metastasis. We investigated the role of IL-35 in monocyte-induced angiogenesis of PDAC in mice. Methods We measured levels of IL35 protein, microvessel density, and numbers of monocytes in 123 sequential PDAC tissues from patients who underwent surgery in China in 2010. We performed studies with the human PDAC cell lines CFPAC-1, BxPC-3, Panc-1, MIA-PaCa-2, and mouse PDAC cell line Pan02. Monocyte subsets were isolated by flow cytometry from human peripheral blood mononuclear cells. Fused human or mouse IL12A and EBI3 genes were overexpressed in PDAC cells or knocked down using small hairpin RNAs. Cells were grown as xenograft tumors in SCID mice; some mice were given injections of an IL35-neutralizing antibody and tumor growth was monitored. We performed chemotaxis assays to measure the ability of IL35 to recruit monocytes. We analyzed mRNA sequences of 179 PDACs in the Cancer Genome Atlas to identify correlations between expression of IL12A and EBI3 and monocyte markers. Monocytes incubated with IL35 or PDAC cell supernatants were analyzed in tube formation and endothelial migration assays. Results In PDAC samples from patients, levels of IL35 mRNA and protein correlated with microvessel density and infiltration of monocyte lineage cells. In cells and mice with xenograft tumors, IL35 increased recruitment of monocytes into PDAC tumors, which required CCL5. Upon exposure to IL35, monocytes increased expression of genes whose products promote angiogenesis (CXCL1 and CXCL8). IL35 activated transcription of CCL5, CXCL1, and CXCL8 by inducing GP130 signaling, via IL12RB2 and phosphorylation of STAT1 and STAT4. A combination of a neutralizing antibody against IL35 and gemcitabine significantly decreased monocyte infiltration, microvessel density, and volume of xenograft tumors grown from PDAC cells in mice. Conclusions PDAC cells produce IL35 to recruit monocytes via CCL5 and induce macrophage to promote angiogenesis via expression of CXCL1 and CXCL8. IL35 signaling promotes angiogenesis and growth of xenograft tumors from PDAC cells in mice. IL35 might serve as a therapeutic target for patients with pancreatic cancer.

    更新日期:2017-10-06
  • Metroticket 2.0 Model for Analysis of Competing Risks of Death Following Liver Transplantation for Hepatocellular Carcinoma
    Gastroenterology (IF 18.392) Pub Date : 2017-10-05
    Vincenzo Mazzaferro, Carlo Sposito, Jian Zhou, Antonio D. Pinna, Luciano De Carlis, Jia Fan, Matteo Cescon, Stefano Di Sandro, He Yi-feng, Andrea Lauterio, Marco Bongini, Alessandro Cucchetti

    Background & Aims Outcomes of liver transplantation for hepatocellular carcinoma (HCC) are determined by cancer-related and non-related events. Treatments for hepatitis C virus (HCV) infection have reduced non-cancer events among patients receiving liver transplants, so reducing HCC-related death might be an actionable endpoint. We performed a competing risk analysis to evaluate factors associated with survival of patients with HCC, and developed a prognostic model based on features of HCC patients before liver transplantation. Methods We performed multivariable competing risk regression analysis to identify factors associated with HCC-specific death of patients who underwent liver transplantation. The training set comprised 1018 patients who underwent liver transplantation for HCC from January 2000 through December 2013 at 3 tertiary centers in Italy. The validation set comprised 341 consecutive patients who underwent liver transplantation for HCC during the same period at the Liver Cancer Institute in Shanghai, China. We collected pre-transplant data on etiology of liver disease, number and size of tumors, patient level of alpha-fetoprotein (AFP), model for end-stage liver disease score, tumor stage, numbers and types of treatment, response to treatments, tumor grade, micro-vascular invasion, dates and causes of death. Death was defined as HCC-specific when related to HCC recurrence after transplant, disseminated extra- and/or intra-hepatic tumor relapse and worsened liver function in presence of tumor spread. The cumulative incidence of death was segregated for HCV status. Results In the competing-risk regression, the sum of tumor number and size and of Log10 level of AFP were significantly associated with HCC-specific death (P<.001), returning an average c-statistic of 0.780 (95% CI, 0.763–0.798). Five-year cumulative incidence of non-HCC–related death were 8.6% in HCV-negative patients and 18.1% in HCV-positive patients. For patients with HCC to have a 70% chance of HCC-specific survival 5 years after transplantation, their level of AFP should be below 200 ng/mL and the sum of number and size of tumors (in cm) should not exceed 7; if the level of AFP was 200–400 ng/mL, the sum of the number and size of tumors should be 5 or less; if their level of AFP was 400–1000 ng/mL, the sum of the number and size of tumors should be 4 or less. In the validation set, the model identified patients who survived 5 years after liver transplantation with 0.721 accuracy (95% CI, 0.648%-0.793%). Our model, based on patients’ level of AFP and HCC number and size, outperformed the Milan, UCSF, Shanghai-Fudan, Up-to-7 criteria (P<.001), and AFP French model (P=.044) to predict which patients will survive for 5 years after liver transplantation. Conclusions We developed a model, based on level of AFP, tumor size and tumor number, to determine risk of death from HCC-related factors after liver transplantation. This model might be used to select endpoints and refine selection criteria for liver transplantation for patients with HCC. To predict 5-years survival and risk of HCC-related death using an online calculator, please see: www.hcc-olt-metroticket.org/

    更新日期:2017-10-05
  • MicroRNA 122, Regulated by GRLH2, Protects Livers of Mice and Patients from Ethanol-induced Liver Disease
    Gastroenterology (IF 18.392) Pub Date : 2017-10-04
    Abhishek Satishchandran, Aditya Ambade, Sitara Rao, Ying-Chao Hsueh, Arvin Iracheta-Vellve, David Tornai, Patrick Lowe, Benedek Gyongyosi, Jia Li, Donna Catalano, Li Zhong, Karen Kodys, Jun Xie, Shashi Bala, Guangping Gao, Gyongyi Szabo

    Background & Aims Chronic, excessive alcohol consumption leads to alcoholic liver disease (ALD) characterized by steatosis, inflammation, and eventually cirrhosis. The hepatocyte specific microRNA 122 (MIR122) regulates hepatocyte differentiation and metabolism. We investigated whether an alcohol-induced decrease in level of MIR122 contributes to development of ALD. Methods We obtained liver samples from 12 patients with ALD and cirrhosis and 9 healthy individuals (controls) and analyzed them by histology and immunohistochemistry. C57Bl/6 mice were placed on a Lieber-DeCarli liquid diet, in which they were fed ethanol for 8 weeks, as a model of ALD, or a control diet. These mice were also given injections of CCl4, to increase liver fibrosis, for 8 weeks. On day 28, mice with ethanol-induced liver disease and advanced fibrosis, and controls, were given injections of recombinant adeno-associated virus 8 vector that expressed the primary miR-122 transcript (pri-MIR122, to overexpress MIR122 in hepatocytes) or vector (control). Two weeks before ethanol feeding, some mice were given injections of a vector that expressed an anti-MIR122, to knock down its expression. Serum and liver tissues were collected; hepatocytes and liver mononuclear cells were analyzed by histology, immunoblots, and confocal microscopy. We performed in silico analyses to identify targets of MIR122 and chromatin immunoprecipitation quantitative PCR analyses in Huh-7 cells. Results Levels of MIR122 were decreased in liver samples from patients with ALD and mice on the Lieber-DeCarli diet, compared with controls. Transgenic expression of MIR122 in hepatocytes of mice with ethanol-induced liver disease and advanced fibrosis significantly reduced serum levels of alanine aminotransferase (ALT) and liver steatosis and fibrosis, compared to mice given injections of the control vector. Ethanol feeding reduced expression of pri-MIR122 by increasing expression of the spliced form of the transcription factor grainyhead like transcription factor 2 (GRHL2) in livers tissues from mice. Levels of GRHL2 were also increased in liver tissues from patients with ALD, compared with controls; increases correlated with decreases in levels of MIR122 in human liver. Mice given injections of the anti-MIR122 before ethanol feeding had increased steatosis, inflammation, and serum levels of ALT compared to mice given a control vector. Levels of hypoxia inducible factor 1 alpha (HIF1A) mRNA, a target of MIR122, were increased in liver tissues from patients and mice with ALD, compared with controls. Mice with hepatocyte-specific disruption of Hif1a developed less-severe liver injury following administration of ethanol, injection of anti-MIR122, or both. Conclusions Levels of MIR122 decrease in livers from patients with ALD and mice with ethanol-induced liver disease, compared with controls. Transcription of MIR122 is inhibited by GRHL2, which is increased in livers of mice and patients with ALD. Expression of an anti-MIR122 worsened the severity of liver damage following ethanol feeding in mice. MIR122 appears to protect the liver from ethanol-induced damage by reducing levels of HIF1A. These processes might be manipulated to reduce the severity of ALD in patients.

    更新日期:2017-10-04
  • Cost Effectiveness of Age-specific Screening Intervals for People with Family Histories of Colorectal Cancer
    Gastroenterology (IF 18.392) Pub Date : 2017-09-28
    Steffie K. Naber, Karen M. Kuntz, Nora B. Henrikson, Marc S. Williams, Ned Calonge, Katrina A.B. Goddard, Doris T. Zallen, Theodore G. Ganiats, Elizabeth M. Webber, A. Cecile J.W. Janssens, Marjolein van Ballegooijen, Ann G. Zauber, Iris Lansdorp-Vogelaar

    Background & Aims Relative risk of colorectal cancer (CRC) decreases with age among individuals with a family history of CRC. However, no screening recommendations specify less frequent screening with increasing age. We aimed to determine whether such a refinement would be cost effective. Methods We determined the relative risk for CRC for individuals based on age and number of affected first-degree relatives (FDRs), using data from publications. For each number of affected FDRs, we used the Microsimulation Screening Analysis model to estimate costs and effects of colonoscopy screening strategies with different age ranges and intervals. Screening was then optimized sequentially, starting with the youngest age group, and allowing the interval of screening to change at certain ages. Strategies with an incremental cost effectiveness ratio below $100,000 per quality-adjusted life year were considered cost effective. Results For people with 1 affected FDR (92% of those with a family history), screening every 3 years beginning at an age of 40 years is most cost effective. If no adenomas are found, the screening interval can gradually be extended to 5 and 7 years, at ages 45 and 55 years, respectively. From a cost effectiveness perspective, individuals with more affected FDRs should start screening earlier and at shorter intervals. However, frequency can be reduced if no abnormalities are found. Conclusions Using a microsimulation model, we found that for individuals with a family history of CRC, it is cost effective to gradually increase the screening interval if several subsequent screening colonoscopies have negative results and no new cases of CRC are found in family members.

    更新日期:2017-09-29
  • The Function of ATPase Copper Transporter ATP7B in Intestine
    Gastroenterology (IF 18.392) Pub Date : 2017-09-25
    Hannah Pierson, Abigael Muchenditsi, Byung-Eun Kim, Martina Ralle, Nicholas Zachos, Dominik Huster, Svetlana Lutsenko

    Background & Aims Wilson disease is a disorder of copper (Cu) misbalance caused by mutations in the ATPase copper transporting beta gene (ATP7B). ATP7B is highly expressed in the liver—the major site of Cu accumulation in patients with Wilson disease. The intestine also expresses ATP7B, but little is known about the contribution of intestinal ATP7B to normal intestinal homeostasis or to Wilson disease manifestations. We characterized the role of ATP7B in mouse intestinal organoids and tissues. Methods We collected intestinal tissues from ATP7B-knockout (Atp7b–/–) and control mice, and establish 3-dimensional enteroids. Immunohistochemistry and X-ray fluorescence were used to characterize the distribution of ATP7B and Cu in tissues. Electron microscopy, histologic analyses, and immunoblotting were used to determine the effects of ATP7B loss. Enteroids derived from control and ATP7B-knockout mice were incubated with excess Cu or with Cu-chelating reagents; effects on cell fat content and ATP7B levels and localization were determined by fluorescent confocal microscopy. Results ATP7B maintains a Cu gradient along the duodenal crypt–villus axis and buffers Cu levels in the cytosol of enterocytes. These functions are mediated by rapid Cu-dependent enlargement of ATP7B-containing vesicles and increased levels of ATP7B. Intestines of Atp7b–/– mice had reduced Cu storage pools in intestine, Cu depletion, accumulation of triglyceride-filled vesicles in enterocytes, mis-localization of apolipoprotein B, and loss of chylomicrons. In primary 3-dimensional enteroids, administration of excess Cu or Cu chelators impaired assembly of chylomicrons. Conclusions ATP7B regulates vesicular storage of Cu in mouse intestine. ATP7B buffers Cu levels in enterocytes to maintain a range necessary for formation of chylomicrons. Misbalance of Cu and lipid in the intestine could account for gastrointestinal manifestations of Wilson disease.

    更新日期:2017-09-29
  • Hepatitis E Virus Lifecycle and Identification of 3 Forms of the ORF2 Capsid Protein
    Gastroenterology (IF 18.392) Pub Date : 2017-09-25
    Claire Montpellier, Czeslaw Wychowski, Ibrahim M. Sayed, Jean-Christophe Meunier, Jean-Michel Saliou, Maliki Ankavay, Anne Bull, André Pillez, Florence Abravanel, François Helle, Etienne Brochot, Hervé Drobecq, Rayan Farhat, Cécile-Marie Aliouat-Denis, Juliano G. Haddad, Jacques Izopet, Philip Meuleman, Anne Goffard, Jean Dubuisson, Laurence Cocquerel

    Background & Aims Hepatitis E virus (HEV) infection is a major cause of acute hepatitis worldwide. Approximately 2 billion people live in areas endemic for HEV and are at risk of infection. The HEV genome encodes 3 proteins, including the ORF2 capsid protein. Detailed analyses of the HEV lifecycle has been hampered by the lack of an efficient viral culture system. Methods We performed studies with gt3 HEV cell culture-produced particles (HEVcc) and patient blood and stool samples. Samples were fractionated on iodixanol gradients and cushions. Infectivity assays were performed in vitro and in human liver chimeric mice. Proteins were analyzed by biochemical and proteomic approaches. Infectious particles were analyzed by transmission electron microscopy. HEV antigen levels were measured with the Wantaï ELISA. Results We developed an efficient cell culture system and isolated HEV particles that were infectious in vitro and in vivo. Using transmission electron microscopy, we defined the ultrastructure of HEVcc and particles from patient sera and stool samples. We also identified the precise sequence of the infectious particle-associated ORF2 capsid protein. In cultured cells and in samples from patients, HEV produced 3 forms of the ORF2 capsid protein: infectious/intracellular ORF2 (ORF2i), glycosylated ORF2 (ORF2g), and cleaved ORF2 (ORF2c). The ORF2i protein associated with infectious particles, whereas the ORF2g and ORF2c proteins were massively secreted glycoproteins not associated with infectious particles. ORF2g and ORF2c were the most abundant antigens detected in sera from patients. Conclusions We developed a cell culture system and characterized HEV particles; we identified 3 ORF2 capsid proteins (ORF2i, ORF2g, and ORFc). These findings will advance our understanding of the HEV lifecycle and improve diagnosis.

    更新日期:2017-09-29
  • Direct Comparison of Diagnostic Performance of 9 Quantitative Fecal Immunochemical Tests for Colorectal Cancer Screening
    Gastroenterology (IF 18.392) Pub Date : 2017-09-25
    Anton Gies, Katarina Cuk, Petra Schrotz-King, Hermann Brenner

    Background & Aims A variety of fecal immunochemical tests (FITs) for hemoglobin (Hb) are used in colorectal cancer (CRC) screening. It is unclear to what extent differences in reported sensitivities and specificities reflect true heterogeneity in test performance or differences in study populations or varying pre-analytical conditions. We directly compared the sensitivity and specificity values with which 9 quantitative (laboratory-based and point of care) FITs detected advanced neoplasms (AN) in a single CRC screening study. Methods Pre-colonoscopy stool samples were obtained from participants of screening colonoscopy in Germany from 2005 through 2010 and frozen at –80°C until analysis. The stool samples were thawed, homogenized, and used for 9 different quantitative FITs in parallel. Colonoscopy and histology reports were collected from all participants and evaluated by 2 independent, trained research assistants who were blinded to the test results. Comparative evaluations of diagnostic performance for AN were made at preset manufacturers´ thresholds (range: 2.0–17.0μg Hb/g feces), at a uniform threshold (15 μg Hb/g feces), and at adjusted thresholds yielding defined levels of specificity (99%, 97%, and 93%). Results Of the 1667 participants who fulfilled the inclusion criteria, all cases with AN (n=216) and 300 randomly selected individuals without AN were included in the analysis. Sensitivities and specificities for AN varied widely when we used the preset thresholds (21.8%–46.3% and 85.7%–97.7%, respectively) or the uniform threshold (16.2%–34.3% and 94.0%–98.0%, respectively). Adjusting thresholds to yield a specificity of 99%, 97%, or 93% resulted in almost equal sensitivities for detection of AN (14.4%–18.5%, 21.3%–23.6%, and 30.1%–35.2%, respectively) and almost equal positivity rates (2.8%–3.4%, 5.8%–6.1% and 10.1%–10.9%, respectively). Conclusions Apparent heterogeneity in diagnostic performance of quantitative FITs can be overcome to a large extent by adjusting thresholds to yield defined levels of specificity or positivity rates. Rather than simply using thresholds recommended by the manufacturer, screening programs should choose thresholds based on intended levels of specificity and manageable positivity rates.

    更新日期:2017-09-29
  • Cholera Vaccine Use Is Associated with a Reduced Risk of Death in Patients with Colorectal Cancer: A Population-based Study
    Gastroenterology (IF 18.392) Pub Date : 2017-09-18
    Jianguang Ji, Jan Sundquist, Kristina Sundquist

    Background & Aims Cholera toxin can act as a modulator of the immune response with anti-inflammatory effects; it reduces development of colon polyps in mouse models of colorectal cancer (CRC). We performed a population-based study to determine whether, in patients with a diagnosis of CRC, subsequent administration of the cholera vaccine (killed Vibrio cholerae O1 whole cells and recombinant cholera toxin B subunit) affects mortality. Methods We identified patients from the Swedish Cancer Register who were diagnosed with CRC from July 2005 through December 2012. These patients were linked to the Swedish Prescribed Drug Register to retrieve cholera vaccine use. We used Cox regression analysis to calculate the hazard ratio (HR) of death from CRC and overall mortality in patients with post-diagnostic use of cholera vaccine compared to matched controls. Results A total of 175 patients were diagnosed with CRC and given a prescription for the cholera vaccine after their cancer diagnosis. Compared to propensity score-matched controls and adjusted for confounding factors, patients with CRC who received the cholera vaccine had a decreased risk of death from CRC (HR, 0.53; 95% CI, 0.29–0.99) and a decreased risk of death overall (HR, 0.59; 95% CI, 0.37–0.94). The decrease in mortality with cholera vaccination was largely observed, irrespective of patient age or tumor stage at diagnosis or sex. Conclusions In a population-based study, we associated administration of the cholera vaccine after CRC diagnosis with decreased risk of death from CRC and overall mortality.

    更新日期:2017-09-19
  • CRISPR/Cas9 Engineering of Adult Mouse Liver Demonstrates That the Dnajb1–Prkaca Gene Fusion is Sufficient to Induce Tumors Resembling Fibrolamellar Hepatocellular Carcinoma
    Gastroenterology (IF 18.392) Pub Date : 2017-09-18
    Lars H. Engelholm, Anjum Riaz, Denise Serra, Frederik Dagnæs-Hansen, Jens V. Johansen, Eric Santoni-Rugiu, Steen H. Hansen, Francesco Niola, Morten Frödin

    Background & Aims Fibrolamellar hepatocellular carcinoma (FL-HCC) is a primary liver cancer that predominantly affects young adults with no underlying liver disease. A somatic, 400 Kb deletion on chromosome 19 that fuses part of the DnaJ heat shock protein family (Hsp40) member B1 gene (DNAJB1) to the protein kinase cAMP-activated catalytic subunit alpha gene (PRKACA) has been repeatedly identified in patients with FL-HCC. However, the DNAJB1–PRKACA gene fusion has not been shown to induce liver tumorigenesis. We used the CRISPR/Cas9 technique to delete in mice the syntenic region on chromosome 8 to create a Dnajb1–Prkaca fusion and monitored the mice for liver tumor development. Methods We delivered CRISPR/Cas9 vectors designed to juxtapose exon 1 of Dnajb1 with exon 2 of Prkaca to create the Dnajb1–Prkaca gene fusion associated with FL-HCC, or control Cas9 vector, via hydrodynamic tail vein injection to livers of 8 week-old female FVB/N mice. These mice did not have any other engineered genetic alterations and were not exposed to liver toxins or carcinogens. Liver tissues were collected 14 months after delivery; genomic DNA was analyzed by PCR to detect the Dnajb1–Prkaca fusion, and tissues were characterized by histology, immunohistochemistry, RNA sequencing, and whole-exome sequencing. Results Livers from 12 of the 15 mice given the vectors to induce the Dnajb1–Prkaca gene fusion, but none of the 11 mice given the control vector, developed neoplasms. The tumors contained the Dnajb1–Prkaca gene fusion and had histologic and cytologic features of human FL-HCCs: large polygonal cells with granular, eosinophilic, and mitochondria-rich cytoplasm, prominent nucleoli, and markers of hepatocytes and cholangiocytes. In comparing expression levels of genes between the mouse tumor and non-tumor liver cells, we identified changes similar to those detected in human FL-HCC, which included genes that affect cell cycle and mitosis regulation. Genomic analysis of mouse neoplasms induced by the Dnajb1–Prkaca fusion revealed a lack of mutations in genes commonly associated with liver cancers, as observed in human FL-HCC. Conclusions Using CRISPR/Cas9 technology, we found generation of the Dnajb1–Prkaca fusion gene in wild-type mice to be sufficient to initiate formation of tumors that have many features of human FL-HCC. Strategies to block DNAJB1–PRKACA might be developed as therapeutics for this form of liver cancer.

    更新日期:2017-09-19
  • Risk of Metachronous High-risk Adenomas and Large Serrated Polyps in Individuals With Serrated Polyps on Index Colonoscopy: Data from the New Hampshire Colonoscopy Registry
    Gastroenterology (IF 18.392) Pub Date : 2017-09-18
    Joseph C. Anderson, Lynn F. Butterly, Christina M. Robinson, Julia E. Weiss, Christopher Amos, Amitabh Srivastava

    Background & Aims Surveillance guidelines for serrated polyps (SPs) are based on limited data on longitudinal outcomes of patients. We used the New Hampshire Colonoscopy Registry to evaluate risk of clinically important metachronous lesions associated with SPs, detected during index colonoscopies. Methods We collected data from a population-based colonoscopy registry that has been collecting and analyzing data on colonoscopies across the state of New Hampshire since 2004, including rates of adenoma and serrated polyp detection. Patients completed a questionnaire to determine demographic characteristics, health history, and risk factors for CRC, and were followed from index colonoscopy through all subsequent surveillance colonoscopies. Our analyses included 5433 participants (median age 61 years; 49.7% male) with 2 colonoscopies (median time to surveillance, 4.9 years). We used multivariable logistic regression models to assess effects of index serrated polyps (SP, n=1016), high-risk adenomas (HRA, n=817), low-risk adenomas (n=1418), and no adenomas (n=3198) on subsequent HRA or large SPs (>1 cm) on surveillance colonoscopy (metachronous lesions). Synchronous SPs, within each index risk group, were assessed for size and by histology. Serrated polyps comprise hyperplastic polyps, sessile serrated adenomas/polyps (SSA/Ps), and traditional serrated adenomas. In this study, SSA/Ps and traditional serrated adenomas are referred to collectively as STSAs. Results HRA and synchronous large SP (odds ratio [OR], 5.61; 95% CI, 1.72–18.28), HRA with synchronous STSA (OR, 16.04; 95% CI, 6.95–37.00), and HRA alone (OR, 3.86; 95% CI, 2.77–5.39) at index colonoscopy significantly increased the risk of metachronous HRA compared to the reference group (no index adenomas or serrated polyps). Large index SPs alone (OR=14.34; 95% CI, 5.03–40.86) or index STSA alone (OR, 9.70; 95% CI, 3.63–25.92) significantly increased the risk of a large metachronous SP. Conclusions In an analysis of data from a population-based colonoscopy registry, we found index large SP or index STSA with no index HRA increased risk of metachronous large SPs but not metachronous HRA. HRA and synchronous SPs at index colonoscopy significantly increased risk of metachronous HRA. Individuals with HRA and synchronous could therefore benefit from close surveillance.

    更新日期:2017-09-19
  • Deficiency of the Mitochondrial NAD Kinase Causes Stress-induced hepatic steatosis in mice
    Gastroenterology (IF 18.392) Pub Date : 2017-09-17
    Kezhong Zhang, Hyunbae Kim, Zhiyao Fu, Yining Qiu, Zhao Yang, Jiemei Wang, Deqiang Zhang, Xin Tong, Lei Yin, Jing Li, Jianmei Wu, Nathan R. Qi, Sander M. Houten, Ren Zhang

    Background & Aims The mitochondrial nicotinamide adenine dinucleotide (NAD) kinase (NADK2, also called MNADK) catalyzes phosphorylation of NAD to yield NADP. Little is known about the functions of mitochondrial NADP and MNADK in liver physiology and pathology. We investigated the effects of reduced mitochondrial NADP by deleting MNADK in mice. Methods We generated MNADK-knockout (KO) mice on a C57BL/6NTac background; mice with a wild-type Mnadk gene were used as controls. Some mice were placed on an atherogenic high-fat diet (16% fat, 41% carbohydrate and 1.25% cholesterol supplemented with 0.5% sodium cholate) or given methotrexate intraperitoneally. We measured rates of fatty acid oxidation in primary hepatocytes using radiolabeled palmitate and in mice using indirect calorimetry. We measured levels of reactive oxygen species in mouse livers and primary hepatocytes. Metabolomic analyses were used to quantify serum metabolites, such as amino acids and acylcarnitines. Results KO mice had metabolic features of MNADK-deficient patients, such as increased serum concentrations of lysine and C10:2 carnitine. When placed on the atherogenic high-fat diet, the KO mice developed features of non-alcoholic fatty liver disease and had increased levels of reactive oxygen species in livers and primary hepatocytes, compared with control mice. During fasting, the KO mice had a defect in fatty acid oxidation. MNADK deficiency reduced the activation of cAMP-responsive element binding protein and hepatocyte specific and peroxisome proliferator-activated receptor alpha, which are transcriptional activators that mediate the fasting response. The activity of mitochondrial sirtuins was reduced in livers of the KO mice. Methotrexate inhibited the catalytic activity of MNADK in hepatocytes and in livers in mice with methotrexate injection. In mice given injections of methotrexate, supplementation of a diet with nicotinamide riboside, a NAD precursor, replenished hepatic NADP and protected the mice from hepatotoxicity, based on markers such as increased level of serum alanine aminotransferase. Conclusion MNADK facilitates fatty acid oxidation, counteracts oxidative damage, maintains mitochondrial sirtuin activity, and prevents metabolic stress-induced non-alcoholic fatty liver disease in mice.

    更新日期:2017-09-19
  • Analysis of Genomes and Transcriptomes of Hepatocellular Carcinomas Identifies Mutations and Gene Expression Changes in the Transforming Growth Factor beta Pathway Short title: Prognostic significance of TGF-β signature in liver cancer
    Gastroenterology (IF 18.392) Pub Date : 2017-09-15
    Jian Chen, Sobia Zaidi, Shuyun Rao, Jiun-Sheng Chen, Liem Phan, Patrizia Farci, Xiaoping Su, Kirti Shetty, Jon White, Fausto Zamboni, Xifeng Wu, Asif Rashid, Nagarajan Pattabiraman, Raja Mazumder, Anelia Horvath, Ray-Chang Wu, Shulin Li, Cuiying Xiao, Chu-Xia Deng, David A. Wheeler, Bibhuti Mishra, Rehan Akbani, Lopa Mishra

    Background & Aims Development of hepatocellular carcinoma (HCC) is associated with alterations in the transforming growth factor beta (TGFβ) signaling pathway, which regulates liver inflammation and can have tumor suppressor or promoter activities. Little is known about the roles of specific members of this pathway at specific of HCC development. We took an integrated approach to identify and validate the effects of changes in this pathway in HCC and identify therapeutic targets. Methods We performed transcriptome analyses for a total of 488 HCCs that include data from The Cancer Genome Atlas. We also screened 301 HCCs reported in the Catalogue of Somatic Mutations in Cancer and 202 from Cancer Genome Atlas for mutations in genome sequences. We expressed mutant forms of spectrin beta, non-erythrocytic 1 (SPTBN1) in HepG2, SNU398, and SNU475 cells and measured phosphorylation, nuclear translocation, and transcriptional activity of SMAD family member 3 (SMAD3). Results We found somatic mutations in at least 1 gene whose product is a member of TGFβ signaling pathway in 38% of HCC samples. SPTBN1 was mutated in the largest proportion of samples (12/202, 6%). Unsupervised clustering of transcriptome data identified a group of HCCs with activation of the TGFβ signaling pathway (increased transcription of genes in the pathway) and a group of HCCs with inactivation of TGFβ signaling (reduced expression of genes in this pathway). Patients with tumors with inactivation of TGFβ signaling had shorter survival times than patients with tumors with activation of TGFβ signaling (P=.0129). Patterns of TGFβ signaling correlated with activation of the DNA damage response and sirtuin signaling pathways. HepG2, SNU398, SNU475 cells that expressed the D1089Y mutant or with knockdown of SPTBN1 had increased sensitivity to DNA crosslinking agents and reduced survival compared to cells that expressed normal SPTBN1 (controls). Conclusions In genome and transcriptome analyses of HCC samples, we found mutations in genes in the TGFβ signaling pathway in almost 40% of samples. These correlated with changes in expression of genes in the pathways; upregulation of genes in this pathway would contribute to inflammation and fibrosis whereas downregulation would indicate loss of TGFβ tumor suppressor activity. Our findings indicate that therapeutic agents for HCCs can be effective, based on genetic features of the TGFβ pathway; agents that block TGFβ should be used only in patients with specific types of HCCs.

    更新日期:2017-09-15
  • Autophagy, Inflammation, and Immune Dysfunction in the Pathogenesis of Pancreatitis
    Gastroenterology (IF 18.392) Pub Date : 2017-09-14
    Anna S. Gukovskaya, Ilya Gukovsky, Hana Algül, Aida Habtezion

    Pancreatitis is a common disorder with significant morbidity and mortality, yet little is known about its pathogenesis and there is no specific or effective treatment. Its development involves dysregulated autophagy and unresolved inflammation, demonstrated by studies in genetic and experimental mouse models. Disease severity depends on whether the inflammatory response resolves or amplifies, leading to multi-organ failure. Dysregulated autophagy might promote the inflammatory response in the pancreas. We discuss the roles of autophagy and inflammation in pancreatitis, mechanisms of deregulation, and connections among disordered pathways. We identify gaps in our knowledge and delineate perspective directions for research. Elucidation of pathogenic mechanisms could lead to new targets for treating or reducing the severity of pancreatitis.

    更新日期:2017-09-14
  • Development and Validation of a Chronic Pancreatitis Prognosis Score in 2 Independent cohorts
    Gastroenterology (IF 18.392) Pub Date : 2017-09-14
    Georg Beyer, Ujjwal M. Mahajan, Christoph Budde, Thomas J. Bulla, Thomas Kohlmann, Louise Kuhlmann, Kerstin Schütte, Ali A. Aghdassi, Eckhard Weber, Ulrich Weiss, Asbjørn M. Drewes, Søren S. Olesen, Markus M. Lerch, Julia Mayerle

    Background & Aims The clinical course of chronic pancreatitis is unpredictable. There is no model to assess disease severity or progression or predict patient outcomes. Methods We performed a prospective study of 91 patients with chronic pancreatitis; data were collected from patients seen at academic centers in Europe, from January 2011 through April 2014. We analyzed correlations between clinical, laboratory, and imaging data with number of hospital readmissions and in-hospital days over the next 12 months; the parameters with the highest degree of correlation were to develop 3-stage chronic pancreatitis prognosis score (COPPS). The predictive value was validated in 129 independent subjects identified from 2 prospective databases. Results The mean number of hospital admissions was 1.9 (95% CI, 1.39–2.44) and 15.2 for hospital days (95% CI, 10.76–19.71) for the development cohort and 10.9 for the validation cohort (95% CI, 7.54–14.30) (P=.08). Based on bivariate correlations, pain (numeric rating scale), level of HbA1c, level of c-reactive protein, body mass index, and platelet count were used to develop the COPPS system. The patients’ median COPPS was 8.9 points (range, 5–14). The system accurately discriminated stages of disease severity (low to high): A (5–6 points), B (7–9), and C (10–15). In Pearson correlation analysis of the development cohort, the COPPS correlated with hospital admissions (0.39; P<.01) and number of hospital days (0.33; P<.01). The correlation was validated in the validation set (Pearson correlation values of 0.36 and 0.44; P<.01). COPPS did not correlate with results from the Cambridge classification system. Conclusions We developed and validated an easy to use dynamic multivariate scoring system, similar to the Child-Pugh-Score for liver cirrhosis. The COPPS allows objective monitoring of patients with chronic pancreatitis, determining risk for readmission to hospital and potential length of hospital stay.

    更新日期:2017-09-14
  • Intestinal Dysbiosis Featuring Abundance of Ruminococcus gnavus Associates With Allergic Diseases in Infants
    Gastroenterology (IF 18.392) Pub Date : 2017-09-12
    Huey-Huey Chua, Hung-Chieh Chou, Ya-Ling Tung, Bor-Luen Chiang, Chien-Chia Liao, Hong-Hsing Liu, Yen-Hsuan Ni

    Background & Aims Dysbiosis of the intestinal microbiota has been associated with development of allergies in infants. However, it is not clear what microbes might contribute to this process. We investigated what microbe(s) might be involved in analyses of infant twins and mice. Methods We studied fecal specimens prospectively in a twin cohort (n=30) and age-matched singletons (n=14) born at National Taiwan University Children’s Hospital, Taipei, Taiwan, from April 2011 to March 2013. Clinical parameters (gestational age, birth body weight, mode of delivery and feeding, immunizations and medical events) were recorded. Fecal samples were collected beginning immediately after birth and for 1 year; the children were followed until 3 years of age and allergic symptoms (repetitive and continuous for at least 6 months) were noted. A skin prick test was used to ascertain atopy. Bacterial communities in fecal samples were profiled by 16S rRNA-based PCR-temporal temperature gradient gel electrophoresis and next generation sequencing. BALB/c mice without and with ovalbumin sensitization/challenge were infected with candidate bacteria by oral gauge intra-gastric intubation. Fecal, serum, lung, and colon tissue samples were collected from mice and analyzed for mechanisms of allergy development. Results During the investigation period, 20 children (45.5%) developed allergic diseases, including respiratory (allergic rhinitis and asthma) and skin (atopic dermatitis and eczema) allergies. Lachnospiraceae were detected at significantly higher frequency in allergic infants than non-allergic infants (P<.004); the high fecal count of Lachnospiraceae in allergic subjects appeared at 2 months of age and persisted until 12 months of age. The enrichment of Lachnospiraceae in allergic infants was attributed to the overgrowth of Ruminococcus gnavus, which tended to have a low frequency in non-allergic subjects (P=.0004). Increased R gnavus was observed before the onset of allergic manifestations, and associated with respiratory allergies (P<.002) or respiratory allergies coexistent with atopic eczema (P<.001). In mice, endogenous R gnavus grew rapidly following sensitization and challenge with ovalbumin. Mice gavaged with purified R gnavus developed airway hyper-responsiveness and had histologic evidence of airway inflammation (asthma). Expansion of R gnavus in mice stimulated secretion of cytokines (interleukin 25 (IL25), IL33, and thymic stromal lymphopoietin) by colon tissues, which activated type-2 innate lymphoid cells and dendritic cells to promote differentiation of T-helper (Th)2 cells and production of their cytokines (IL4, IL5, and IL13). This led to infiltration of the colon and lung parenchyma by eosinophils and mast cells. Conclusions In a study of a twin cohort (some infants with, some without allergies), we associated development of allergies, particularly respiratory allergies, with increased fecal abundance of R gnavus. Mice fed R gnavus developed airway inflammation, characterized by expansion of Th2 cells in the colon and lung, and infiltration of colon and lung parenchyma by eosinophils and mast cells.

    更新日期:2017-09-12
  • Association Between Germline Mutations in BRF1, a subunit of the RNA Polymerase III Transcription Complex, and Hereditary Colorectal Cancer
    Gastroenterology (IF 18.392) Pub Date : 2017-09-12
    Fernando Bellido, Nadine Sowada, Pilar Mur, Conxi Lázaro, Tirso Pons, Rafael Valdés-Mas, Marta Pineda, Gemma Aiza, Silvia Iglesias, José Luís Soto, Miguel Urioste, Trinidad Caldés, Milagros Balbín, Pilar Blay, Daniel Rueda, Mercedes Durán, Alfonso Valencia, Victor Moreno, Joan Brunet, Ignacio Blanco, Matilde Navarro, George A. Calin, Guntram Borck, Xose S. Puente, Gabriel Capellá, Laura Valle

    Background & Aims Although there is a genetic predisposition to colorectal cancer (CRC), few of the genes that affect risk have been identified. We performed whole-exome sequence analysis of individuals in a high-risk family without mutations in genes previously associated with CRC risk to identify variants associated with inherited CRC. Methods We collected blood samples from 3 relatives with CRC in Spain (65, 62 and 40 years old at diagnosis) and perfomed whole-exome sequence analyses. Rare missense, truncating or splice-site variants shared by the 3 relatives were selected. We used targeted pooled DNA amplification followed by next-generation sequencing to screen for mutations in candidate genes in 547 additional hereditary and/or early-onset CRC cases. We carried out protein-dependent yeast-growth assays and transfection studies in the HT29 human CRC cell line to test the effects of the identified variants. Results A total of 42 unique or rare (population minor allele frequency below 1%) non-synonymous genetic variants in 38 genes were shared by all 3 relatives. We selected the BRF1 gene, which encodes an RNA polymerase III transcription initiation factor subunit for further analysis, based on the predicted effect of the identified variant and previous association of BRF1 with cancer. Previously unreported or rare germline variants in BRF1 were identified in 11/503 individuals in families with a history of CRC or early-onset CRC,- a significantly greater proportion than in control population (34/4,300). Seven of the identified variants (1 detected in 2 families) affected BRF1 mRNA splicing, protein stability or expression and/or function. Conclusions In an analysis of families with a history of CRC, we associated germline mutations in BRF1 with predisposition to CRC. We associated deleterious BRF1 variants with 1.4% of familial CRC cases, in individuals without mutations in high-penetrance genes previously associated with CRC. Our findings add additional evidence to the link between defects in genes that regulate ribosome synthesis and risk of CRC.

    更新日期:2017-09-12
  • A Nigro-Vagal Pathway Controls Gastric Motility and is Affected in a Rat Model of Parkinsonism
    Gastroenterology (IF 18.392) Pub Date : 2017-09-11
    Laura Anselmi, Luca Toti, Cecilia Bove, Jessica Hampton, R. Alberto Travagli

    Background & Aims In most patients with Parkinson’s disease, gastrointestinal (GI) dysfunctions, such as gastroparesis and constipation, are prodromal to the cardinal motor symptoms of the disease. Sporadic Parkinson’s disease has been proposed to develop following ingestion of neurotoxicants that affect the brain–gut axis via the vagus nerve, and then travel to higher centers compromising the substantia nigra pars compacta (SNpc), and, later, the cerebral cortex. We aimed to identify the pathway that connects the brainstem vagal nuclei and the SNpc, and to determine whether this pathway is compromised in a rat model of Parkinsonism. Methods To study this neural pathway in rats, we placed tracers in the dorsal vagal complex (DVC) or SNpc; brainstem and midbrain were examined for tracer distribution and neuronal neurochemical phenotype. Rats were given injections of paraquat once weekly for 3 weeks to induce features of Parkinsonism, or vehicle (control). Gastric tone and motility were recorded following NMDA microinjection in the SNpc and/or optogenetic stimulation of nigro-vagal terminals in the DVC. Results Stimulation of the SNpc increased gastric tone and motility via activation of dopamine 1 receptors in the DVC. In the paraquat-induced model of Parkinsonism, this nigro-vagal pathway was compromised during the early stages of motor deficit development. Conclusions We identified and characterized a nigro-vagal monosynaptic pathway in rats that controls gastric tone and motility. This pathway might be involved in the prodromal gastric dysmotility observed in patients with early-stage Parkinson’s disease.

    更新日期:2017-09-11
  • Paneth Cell Defects Induce Microbiota Dysbiosis In Mice And Promote Visceral Hypersensitivity
    Gastroenterology (IF 18.392) Pub Date : 2017-09-01
    Ambre Riba, Maïwenn Olier, Sonia Lacroix-Lamandé, Corinne Lencina, Valérie Bacquié, Cherryl Harkat, Marion Gillet, Marine Baron, Caroline Sommer, Virginie Mallet, Christel Salvador-Cartier, Fabrice Laurent, Vassilia Théodorou, Sandrine Ménard

    Background & Aims Separation of newborn rats from their mothers induces visceral hypersensitivity and impaired epithelial secretory cell lineages when they are adults. Little is known about the mechanisms by which maternal separation causes visceral hypersensitivity or its relationship with defects in epithelial secretory cell lineages. Methods We performed studies with C3H/HeN mice separated from their mothers as newborns and mice genetically engineered (Sox9flox/flox-vil-cre on C57BL/6 background) to have deficiencies in Paneth cells. Paneth cells deficiency was assessed by lysozyme staining of ileum tissues and lysozyme activity in fecal samples. When mice were 50 days old, their abdominal response to colorectal distension was assessed by electromyography. Fecal samples were collected and microbiota were analyzed using GULDA quantitative PCR. Results Mice with maternal separation developed visceral hypersensitivity and defects in Paneth cells, as reported from rats, compared to mice without maternal separation. Sox9flox/flox-vil-Cre mice also had increased visceral hypersensitivity compared to control littermate Sox9flox/flox mice. Fecal samples from mice with maternal separation and from Sox9flox/flox-vil-cre mice had evidence for intestinal dysbiosis of the microbiota, characterized by expansion of Escherichia coli. Daily gavage of conventional C3H/HeN adult mice with 109 commensal E. coli induced visceral hypersensitivity. Conversely, daily oral administration of lysozyme prevented expansion of E. coli during maternal separation and visceral hypersensitivity. Conclusions Mice with defects in Paneth cells (induced by maternal separation or genetically engineered) have intestinal expansion of E. coli leading to visceral hypersensitivity. These findings provide evidence that Paneth cell function and intestinal dysbiosis are involved in visceral sensitivity.

    更新日期:2017-09-04
  • Anesthesia Assistance in Outpatient Colonoscopy and Risk of Aspiration Pneumonia, Bowel Perforation, and Splenic Injury
    Gastroenterology (IF 18.392) Pub Date : 2017-09-01
    Barbara Bielawska, Lawrence C. Hookey, Rinku Sutradhar, Marlo Whitehead, Jianfeng Xu, Lawrence F. Paszat, Linda Rabeneck, Jill Tinmouth

    Background & Aims The increase in use of anesthesia assistance (AA) to achieve deep sedation with propofol during colonoscopy has significantly increased colonoscopy costs without evidence for increased quality and with possible harm. We investigated the effects of AA on colonoscopy complications, specifically bowel perforation, aspiration pneumonia, and splenic injury. Methods In a population-based cohort study using administrative databases, we studied adults in Ontario, Canada undergoing outpatient colonoscopy from 2005 through 2012. Patient, endoscopist, institution, and procedure factors were derived. The primary outcome was bowel perforation, defined using a validated algorithm. Secondary outcomes were splenic injury and aspiration pneumonia. Using a matched propensity score approach, we matched persons who had colonoscopy with AA (1:1) to those who did not. We used logistic regression models under a generalized estimating equations approach to explore the relationship between AA and outcomes. Results We analyzed data from 3,059,045 outpatient colonoscopies; 862,817 of these included AA. After propensity matching, a cohort of 793,073 patients who had AA and 793,073 without AA was retained for analysis (51%, female; 78% were age 50 years or older). Use of AA did not significantly increase risk of perforation (odds ratio [OR], 0.99; 95% CI, 0.84 – 1.16) or splenic injury (OR, 1.09; 95% CI, 0.62 – 1.90]. Use of AA was associated with an increased risk of aspiration pneumonia (OR, 1.63; 95% CI, 1.11 – 2.37). Conclusions In a population-based cohort study, AA for outpatient colonoscopy was associated with a significantly increased risk of aspiration pneumonia but not bowel perforation or splenic injury. Endoscopists should warn patients, especially those with respiratory compromise, of this risk.

    更新日期:2017-09-04
  • Association Between Inflammatory Diet Pattern and Risk of Colorectal Carcinoma Subtypes Classified by Immune Responses to Tumor
    Gastroenterology (IF 18.392) Pub Date : 2017-09-01
    Li Liu, Reiko Nishihara, Zhi Rong Qian, Fred K. Tabung, Daniel Nevo, Xuehong Zhang, Mingyang Song, Yin Cao, Kosuke Mima, Yohei Masugi, Yan Shi, Annacarolina da Silva, Tyler Twombly, Mancang Gu, Wanwan Li, Tsuyoshi Hamada, Keisuke Kosumi, Kentaro Inamura, Jonathan A. Nowak, David A. Drew, Paul Lochhead, Katsuhiko Nosho, Kana Wu, Molin Wang, Wendy S. Garrett, Andrew T. Chan, Charles S. Fuchs, Edward L. Giovannucci, Shuji Ogino

    Background & Aims Dietary patterns affect systemic and local intestinal inflammation, which have been linked to colorectal carcinogenesis. Chronic inflammation can interfere with the adaptive immune response. We investigated whether the association of a diet that promotes intestinal inflammation with risk of colorectal carcinoma was stronger for tumors with lower lymphocytic reactions than tumors with higher lymphocytic reactions. Methods We collected data from the molecular pathological epidemiology databases of 2 prospective cohort studies: the Nurses’ Health Study (since 1976) and the Health Professional Follow-up Study (since 1986). We used duplication-method time-varying Cox proportional cause-specific hazards regression to assess the association of empirical dietary inflammatory pattern (EDIP) score (derived from food frequency questionnaire data) with colorectal carcinoma subtype. Foods that contribute to high EDIP scores include red and processed meats, refined grains, carbonated beverages, and some vegetables; foods that contribute to low EDIP scores include beer, wine, coffee, tea, yellow and leafy vegetables, and fruit juice. Colorectal tissue samples were analyzed histologically for patterns of lymphocytic reactions (Crohn’s-like lymphoid reaction, peritumoral lymphocytic reaction, intratumoral periglandular reaction, and tumor-infiltrating lymphocytes). Results During follow up of 124,433 participants, we documented 1311 incident colon and rectal cancer cases with available tissue data. The association between the EDIP and colorectal cancer risk was significant (Ptrend = .02), and varied with degree of peritumoral lymphocytic reaction (Pheterogeneity < .001). Higher EDIP scores were associated with increased risk of colorectal cancer with an absent or low peritumoral lymphocytic reaction (highest vs lowest EDIP score quintile hazard ratio = 2.60; 95% CI, 1.60–4.23; Ptrend < .001) but not risk of tumors with intermediate or high peritumoral lymphocytic reaction (Ptrend > .80). Conclusions In a prospective cohort study, we associated inflammatory diets with a higher risk of colorectal cancer subtype that contains little or no peritumoral lymphocytic reaction. These findings suggest that diet-related inflammation might contribute to development of colorectal cancer, by suppressing the adaptive anti-tumor immune response.

    更新日期:2017-09-04
  • Abnormal Responses to Local Esophageal Food Allergen Injections in Adult Patients with Eosinophilic Esophagitis
    Gastroenterology (IF 18.392) Pub Date : 2017-09-01
    Marijn J. Warners, Ingrid Terreehorst, René M. van den Wijngaard, Jaap Akkerdaas, Betty C.A.M. van Esch, Ronald van Ree, Serge A. Versteeg, Andreas J.P.M. Smout, Albert J. Bredenoord

    Skin tests and measurement of serum levels of immunoglobulin E do not accurately identify foods for elimination from the diets of patients with eosinophilic esophagitis (EoE). We investigated whether an esophageal prick test (EPT), in which the esophageal mucosa is challenged by local injection of allergen extracts, could identify individuals with esophageal sensitization. During endoscopy 6 allergens were injected in the esophagus of 8 patients with EoE and 3 patients without EoE (controls). A second endoscopy was performed after 24 hrs to evaluate delayed responses. Five of the 8 patients with EoE had evidence for an acute response (luminal obstruction and mucosal blanching); 2 other patients had a delayed wheal or flare reaction. No responses were observed in controls. We conclude that esophageal mucosal food allergen injections induce acute and/or delayed responses in patients with EoE but not controls. The EPT deserves further exploration because it might guide elimination diets.

    更新日期:2017-09-04
  • Gastrin Induces Nuclear Export and Proteasome Degradation of Menin in Enteric Glial Cells
    Gastroenterology (IF 18.392) Pub Date : 2017-08-30
    Sinju Sundaresan, Cameron A. Meininger, Anthony J. Kang, Amanda L. Photenhauer, Michael M. Hayes, Nirakar Sahoo, Jolanta Grembecka, Tomasz Cierpicki, Lin Ding, Thomas J. Giordano, Tobias Else, David J. Madrigal, Malcolm J. Low, Fiona Campbell, Ann-Marie Baker, Haoxing Xu, Nicholas A. Wright, Juanita L. Merchant

    Background & Aims The multiple endocrine neoplasia, type 1 (MEN1) locus encodes the nuclear protein and tumor suppressor menin. MEN1 mutations frequently cause neuroendocrine tumors (NETs) such as gastrinomas, characterized by their predominant duodenal location and local metastasis at time of diagnosis. Diffuse gastrin cell hyperplasia precedes the appearance of MEN1 gastrinomas, which develop within submucosal Brunner’s glands. We investigated how menin regulates expression of the gastrin gene and induces generation of submucosal gastrin-expressing cell hyperplasia. Methods Primary enteric glial cultures were generated from the VillinCre:Men1FL/FL:Sst–/– mice or C57BL/6 mice (controls), with or without inhibition of gastric acid by omeprazole. Primary enteric glial cells from VillinCre:Men1FL/FL:Sst+/+ mice were incubated with gastrin and separated into nuclear and cytoplasmic fractions. Cells were incubated with forskolin and H89 to activate or inhibit protein kinase A (a family of enzymes whose activity depends on cellular levels of cyclic AMP). Gastrin was measured in blood, tissue, and cell cultures using an ELISA. Immunoprecipitation with menin or ubiquitin was used to demonstrate post-translational modification of menin. Primary glial cells were incubated with leptomycin b and MG132 to block nuclear export and proteasome activity, respectively. We obtained human duodenal, lymph node, and pancreatic gastrinoma samples, collected from patients who underwent surgery from 1996 through 2007 in the United States or the United Kingdom. Results Enteric glial cells that stained positive for glial fibrillary acidic protein (GFAP+) expressed gastrin de novo through a mechanism that required PKA. Gastrin-induced nuclear export of menin via cholecystokinin B receptor (CCKBR)-mediated activation of PKA. Once exported from the nucleus, menin was ubiquitinated and degraded by the proteasome. GFAP and other markers of enteric glial cells, e.g., p75 and S100B, colocalized with gastrin in human duodenal gastrinomas. Conclusions MEN1-associated gastrinomas, which develop in the submucosa, might arise from enteric glial cells through hormone-dependent PKA signaling. This pathway disrupts nuclear menin function, leading to hypergastrinemia and associated sequelae.

    更新日期:2017-08-31
  • Degradation of PHLPP2 by KCTD17, via a Glucagon-dependent Pathway, Promotes Hepatic Steatosis
    Gastroenterology (IF 18.392) Pub Date : 2017-08-30
    KyeongJin Kim, Dongryeol Ryu, Paola Dongiovanni, Lale Ozcan, Shruti Nayak, Beatrix Ueberheide, Luca Valenti, Johan Auwerx, Utpal B. Pajvani

    Background & Aims Obesity-induced non-alcoholic fatty liver disease (NAFLD) develops, in part, via excess insulin-stimulated hepatic de novo lipogenesis, which increases, paradoxically, in patients with obesity-induced insulin resistance. Pleckstrin homology domain leucine-rich repeat protein phosphatase 2 (PHLPP2) terminates insulin signaling by dephosphorylating Akt; levels of PHLPP2 are reduced in livers from obese mice. We investigated whether loss of hepatic PHLPP2 is sufficient to induce fatty liver in mice, mechanisms of PHLPP2 degradation in fatty liver, and expression of genes that regulate PHLPP2 in livers of patients with NAFLD. Methods C57BL/6J mice (controls), obese db/db mice and mice with liver-specific deletion of PHLPP2 (L-PHLPP2) fed either normal chow or high-fat diet (HFD) were analyzed for metabolic phenotypes including glucose tolerance and hepatic steatosis. PHLPP2-deficient primary hepatocytes or CRISPR/Cas9-mediated PHLPP2-knockout hepatoma cells were analyzed for insulin signaling and gene expression. We performed mass spectrometry analyses of livers tissues from C57BL/6J mice transduced with Ad-HA-FLAG-PHLPP2 to identify post-translational modifications to PHLPP2 and proteins that interact with PHLPP2. We measured levels of mRNAs by quantitative reverse transcription PCR in liver biopsies from patients with varying degrees of hepatic steatosis. Results PHLPP2-knockout hepatoma cells and hepatocytes from L-PHLPP2 mice showed normal initiation of insulin signaling, but prolonged insulin action. Chow-fed L-PHLPP2 mice had normal glucose tolerance but hepatic steatosis. In HFD-fed C57BL/6J or db/db obese mice, endogenous PHLPP2 was degraded by glucagon and PKA-dependent phosphorylation of PHLPP2 (at Ser1119 and Ser1210), which led to PHLPP2 binding to potassium channel tetramerization domain containing 17 (KCTD17), a substrate-adaptor for Cul3-RING ubiquitin ligases. Levels of KCTD17 mRNA were increased in livers of HFD-fed C57BL/6J or db/db obese mice and in liver biopsies patients with NAFLD, compared with liver tissues from healthy control mice or patients without steatosis. Knockdown of KCTD17 with small hairpin RNA in primary hepatocytes increased PHLPP2 protein but not Phlpp2 mRNA, indicating that KCTD17 mediates PHLPP2 degradation. KCTD17 knockdown in obese mice prevented PHLPP2 degradation and decreased expression of lipogenic genes. Conclusions In mouse models of obesity, we found that PHLPP2 degradation induced lipogenesis without affecting gluconeogenesis. KCTD17, which is upregulated in liver tissues of obese mice and patients with NAFLD, binds to phosphorylated PHLPP2 to target it for ubiquitin-mediated degradation; this increases expression of genes that regulate lipogenesis to promote hepatic steatosis. Inhibitors of this pathway might be developed for treatment of patients with NAFLD.

    更新日期:2017-08-31
  • Analysis of Liver Offers to Pediatric Candidates on the Transplant Wait List
    Gastroenterology (IF 18.392) Pub Date : 2017-07-13
    E.K. Hsu, M.L. Shaffer, L. Gao, C. Sonnenday, M.L. Volk, J. Bucuvalas, J.C. Lai

    Background & Aims Approximately 10% of children on the liver transplant wait-list in the United States (US) die every year. We examined deceased donor liver offer acceptance patterns and their contribution to pediatric wait-list mortality. Methods We performed a retrospective cohort study of children on the US liver transplant wait-list from 2007 through 2014 using national transplant registry databases. We determined the frequency, patterns of acceptance, and donor and recipient characteristics associated with deceased donor liver organ offers for children who died or were delisted compared to those who underwent transplantation. Children who died or were delisted were classified by the number of donor liver offers (0 vs 1 or more), limiting analyses to offers of livers that were ultimately transplanted into pediatric recipients. The primary outcome was death or delisting on the wait-list. Results Among 3852 pediatric liver transplant candidates, children who died or were delisted received a median 1 pediatric liver offer (inter-quartile range, 0–2) and waited a median 33 days before removal from the waitlist. Of 11328 donor livers offered to children, 2533 (12%) were transplanted into children—1179 of these (47%) were immediately accepted and 1354 (53%) were initially refused and eventually accepted for another child. Of 27831 adults, 1667 (6.0%; median 55 years) received livers from donors younger than 18 yrs (median 15 yrs), most (97%) allocated locally or regionally. Of children who died or were delisted, 173 (55%) received an offer of 1 or more liver that was subsequently transplanted into another pediatric recipient, and 143 (45%) died or were delisted with no offers. Conclusions Among pediatric liver transplant candidates in the US, children who died or were delisted received a median 1 pediatric liver offer and waited a median 33 days. Of livers transplanted into children, 47% were immediately accepted and 53% were initially refused and eventually accepted for another child. Of children who died or were delisted, 55% received an offer of 1 or more liver that was subsequently transplanted into another pediatric recipient, and 45% died or were delisted with no offers. Pediatric prioritization in allocation and development of improved risk stratification systems is required to reduce wait-list mortality among children.

    更新日期:2017-08-30
  • Randomized Comparison of 3 High-level Disinfection and Sterilization Procedures for Duodenoscopes
    Gastroenterology (IF 18.392) Pub Date : 2017-07-13
    Graham M. Snyder, Sharon B. Wright, Anne Smithey, Meir Mizrahi, Michelle Sheppard, Elizabeth B. Hirsch, Ram Chuttani, Riley Heroux, David S. Yassa, Lovisa B. Olafsdottir, Roger B. Davis, Anastasiou Jiannis, Vijay Bapat, Kiran Bidari, Douglas K. Pleskow, Daniel Leffler, Benjamin Lane, Alice Chen, Mandeep S. Sawhney

    Background and Aims Duodenoscopes have been implicated in the transmission of multi-drug resistant bacteria (MDRO). We compared the frequency of duodenoscope contamination with MDRO or any other bacteria after disinfection or sterilization by 3 different methods. Methods We performed a single-center prospective randomized study in which duodenoscopes were randomly reprocessed by standard high-level disinfection (sHLD), double high-level disinfection (dHLD), or standard high-level disinfection followed by ethylene oxide gas sterilization (HLD/ETO). Samples were collected from the elevator mechanism and working channel of each duodenoscope and cultured before use. The primary outcome was the proportion of duodenoscopes with an elevator mechanism or working channel culture showing 1 or more MDRO; secondary outcomes included the frequency of duodenoscope contamination with more than 0 and 10 or more colony-forming units (CFU) of aerobic bacterial growth on either sampling location. Results After 3 months of enrollment, the study was closed due to the futility—we did not observe sufficient events to evaluate the primary outcome. Among 541 duodenoscope culture events, 516 were included in the final analysis. No duodenoscope culture in any group was positive for MDRO. Bacterial growth of more than 0 CFU was noted in 16.1% duodenoscopes in the sHLD group, 16.0% in the dHLD group, and 22.5% in the HLD/ETO group (P=.21). Bacterial growth or 10 or more CFU was noted in 2.3% of duodenoscopes in sHLD group, 4.1% in the dHLD group, and 4.2% in the HLD/ETO group (P=.36). MRDOs were cultured from 3.2% of pre-procedure rectal swabs and 2.5% of duodenal aspirates. Conclusions In a comparison of duodenoscopes reprocessed by sHLD, dHLD, or HLD/ETO, we found no significant differences between groups for MDRO or bacteria contamination. Enhanced disinfection methods (dHLD or HLD/ETO) did not provide additional protection against contamination. However, insufficient events occurred to assess our primary study end-point. ClinicalTrials.gov no: NCT02611648

    更新日期:2017-08-30
  • Vasoactive Intestinal Polypeptide and Mast Cells Regulate Increased Passage of Colonic Bacteria in Patients With Irritable Bowel Syndrome
    Gastroenterology (IF 18.392) Pub Date : 2017-07-13
    Olga Bednarska, Susanna A. Walter, Maite Casado-Bedmar, Magnus Ström, Eloísa Salvo-Romero, Maria Vicario, Emeran A. Mayer, Åsa V. Keita

    Background & Aims Irritable bowel syndrome (IBS) is associated with intestinal dysbiosis and symptoms of IBS develop following gastroenteritis. We aimed to study passage of live bacteria through the colonic epithelium, and determine the role of mast cells and vasoactive intestinal polypeptide (VIP) in barrier regulation in IBS and healthy individuals. Methods Colon biopsies from 32 women with IBS and 15 age-matched healthy women (controls) were mounted in Ussing chambers; we measured numbers of fluorescently labeled Escherichia coli HS and Salmonella typhimurium that passed through from the mucosal side to the serosal side of the tissue. Some biopsies were exposed to agents that block the VIP receptors (VPAC1 and VPAC2) or mast cells. Levels of VIP and tryptase were measured in plasma and biopsy lysates. Number of mast cells and mast cells that express VIP or VIP receptors were quantified by immunofluorescence. Biopsies from an additional 5 patients with IBS and 4 controls were mounted in chambers and Salmonella were added; we studied passage routes through the epithelium by transmission electron microscopy and expression of tight junctions by confocal microscopy Results In colon biopsies from patients with IBS, larger numbers of E coli HS and Salmonella passed through the epithelium than in biopsies from controls (P<.0005). In transmission electron microscopy analyses, bacteria were found to cross the epithelium via only the transcellular route. Bacterial passage was reduced in biopsies from patients with IBS and controls after addition of antibodies against VPACs or ketotifen, which inhibits mast cells. Plasma samples from patients with IBS had higher levels of VIP than plasma samples from controls. Biopsies from patients with IBS had higher levels of tryptase, larger numbers of mast cells, and a higher percentage of mast cells that express VPAC1 than biopsies from controls. In biopsies from patients with IBS, addition of Salmonella significantly reduced levels of occludin; subsequent addition of ketotifen significantly reversed this effect. Conclusions We found that colonic epithelium tissues from patients with IBS have increased translocation of commensal and pathogenic live bacteria, compared with controls. Mechanisms of increased translocation include mast cells and VIP.

    更新日期:2017-08-30
Some contents have been Reproduced with permission of the American Chemical Society.
Some contents have been Reproduced by permission of The Royal Society of Chemistry.
化学 • 材料 期刊列表