当前期刊: Molecular Therapy - Oncolytics Go to current issue    加入关注   
显示样式:        排序: 导出
  • Inhibition of USP14 deubiquitinating activity as a potential therapy for tumors with p53 deficiency
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2020-01-11
    Yu-Shui Ma; Xiao-Feng Wang; Yun-Jie Zhang; Pei Luo; Hui-Deng Long; Liu Li; Hui-Qiong Yang; Ru-Ting Xie; Cheng-You Jia; Gai-Xia Lu; Zheng-Yan Chang; Jia-Jia Zhang; Shao-Bo Xue; Zhong-Wei Lv; Fei Yu; Qing Xia; Da Fu
  • CircRNA circFUT8 upregulates Krüpple-like factor 10 to inhibit the metastasis of bladder cancer via sponging miR-570-3p
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2020-01-11
    Qingqing He; Dong Yan; Wei Dong; Junming Bi; Lifang Huang; Meihua Yang; Jian Huang; Haide Qin; Tianxin Lin

    Circular RNAs (circRNAs) are broad and diverse endogenous non-coding RNAs. Emerging evidence has revealed that circRNAs play pivotal roles in cancers, regulating the gene expression by acting as microRNA (miRNA) sponge. However, the biological functions of circRNAs in bladder cancer (BCa) remain largely unknown. In this study, we identified an altered circRNA termed circFUT8 by screening RNA sequencing data generated from three BCa tissues and matched adjacent normal bladder tissues. Quantitative real-time PCR (qRT-PCR) analysis demonstrated circFUT8 was downregulated in BCa tissues and correlated with patients’ prognosis, histological grade and lymph node (LN) metastasis. Functionally, gain and loss of function assays indicated circFUT8 inhibited the migration and invasion of BCa cell lines in vitro and LN metastasis in vivo. Mechanistically, circFUT8 directly bound to miR-570-3p and partially abrogated its oncogenic role, and miR-570-3p could suppress the expression of tumor suppressor gene Krüpple-like factor 10 (KLF10) by binding its 3′ untranslated region (3’ UTR). Moreover, we found that circFUT8 promoted the expression of KLF10 by competitively sponging miR-570-3p. In conclusion, circFUT8 functions as a tumor suppressor in BCa cells by targeting miR-570-3p/KLF10 axis and may serve as a potential biomarker and therapeutic target for the management of BCa patients with LN metastasis.

  • Wnt7a counteracts cancer cachexia
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2020-01-11
    Manuel Schmidt; Christine Poser; Julia von Maltzahn

    Cancer cachexia is a complex metabolic disease so far lacking effective therapy accounting for approximately one third of all cancer-related deaths worldwide. The extracellular ligand Wnt7a has a dual function in skeletal muscle inducing the anabolic AKT/mTOR pathway in myofibers and driving muscle stem cell expansion in skeletal muscle making it a promising candidate for treatment of muscle wasting diseases. In murine and human myotubes Wnt7a activates the anabolic AKT/mTOR pathway thereby preventing cachexia induced atrophy with a single application being sufficient to prevent atrophy independently of the tumor cell type causing cachexia. Addition of Wnt7a also improved activation and differentiation of muscle stem cells in cancer cachexia, a condition under which skeletal muscle regeneration is severely impaired due to stalled muscle stem cell differentiation. Finally, we show that Wnt7a prevents cancer cachexia in an in vivo mouse model based on C26 colon carcinoma cells. Wnt7a has a dual role in cachectic skeletal muscle, it effectively counteracts muscle wasting through activation of the anabolic AKT/mTOR pathway and furthermore reverts the loss of muscle stem cell functionality due to cancer cachexia making Wnt7a a promising candidate for an ameliorative treatment of cancer cachexia.

  • oHSV2 can target murine colon carcinoma by altering the immune status of the tumor microenvironment and inducing specific antitumor immunity
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2020-01-11
    Wen Zhang; Xiao Hu; Jing Liang; Yujie Zhu; Beibei Zeng; Lin Feng; Changyun Zhao; Shangmei Liu; Binlei Liu; Kaitai Zhang

    Oncolytic viruses are promising immunoreagents. Numerous studies have shown that oncolytic virotherapy is effective for many tumors. Herein, we investigated the therapeutic effect of oHSV2, an oncolytic type 2 herpes simplex virus, on mouse colon carcinoma. The in vivo antitumor efficacy of oHSV2 was observed in both unilateral and bilateral colon cancer models. oHSV2 effectively eliminated tumors and prolonged the survival of mice without side effects. Additionally, treatment with oHSV2 effectively prevented the growth of rechallenged tumors and distant implanted tumors. The specific killing ability of splenic immune cells to tumor cells was enhanced. oHSV2 treatment effectively reduced the content of inhibitory immune cells (Tregs and MDSCs) and increased the content of positive immune cells (NK, CD8+ T and DCs) in the spleen. Moreover, treatment with oHSV2 remodeled the tumor immune microenvironment. In summary, treatment with oHSV2 can effectively eliminate primary tumors, generate tumor-specific immunity and elicit immune memory to inhibit tumor recurrence and metastasis. Furthermore, this virotherapy can reshape the immune status of the spleen and tumor microenvironment in mice, which can further improve the therapeutic antitumor effect.

  • IRS2 amplification as a predictive biomarker in response to ceritinib in small cell lung cancer
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2020-01-10
    Mi-Sook Lee; Kyungsoo Jung; Ji-Young Song; Min-Jung Sung; Sung-Bin Ahn; Doo-Yi Oh; Yoon-La Choi

    Small cell lung cancer (SCLC) is a fast-growing and malignant cancer that responds well to chemotherapy; however, the survival rate is less than 15% after 2 years of diagnosis. Therefore, novel therapeutic agents for treating SCLC patients need to be evaluated. This study aims to identify the therapeutic targets based on the comprehensive genomic profiling of SCLC patients. Among the molecular-profiled SCLC samples obtained using targeted sequencing, the array-based comparative genomic hybridization (array CGH) identified focal insulin receptor substrate 2 (IRS2) amplification in the SCLC patients. IRS2 amplification was confirmed in 5% of 73 SCLC patients. To determine whether IRS2 amplification could act as a therapeutic target, we generated a patient-derived xenograft (PDX) model and subsequently screened 43 targeted agents using the PDX derived cells (PDCs). Ceritinib significantly inhibited the cell growth and impaired the tumor sphere formation in IRS2-expressing PDCs. Its effects were confirmed in various in vitro assays and were further validated in the mouse xenograft models. In this study, we present that IRS2 amplification and/or expression serve as preclinical implications for a novel therapeutic target in SCLC progression. Furthermore, we suggest that IGF-1 receptor inhibitor-based therapy could be used for treating SCLC with IRS2 amplification.

  • Resveratrol inhibits the tumorigenesis of follicular thyroid cancer via ST6GAL2-regulated activation of the Hippo signaling pathway
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2020-01-10
    Gaoran Xu; Junzhu Chen; Guorong Wang; Junhong Xiao; Ning Zhang; Yanyu Chen; Haoran Yu; Guangzhi Wang; Yongfu Zhao

    Follicular thyroid carcinoma (FTC) is a common endocrine malignancy with highly aggressive features. In this study, next-generation sequencing technology was used to identify aberrant expression of sialyltransferase (ST) family members in FTC. Aberrant high expression of alpha-2, 6-sialyltransferase 2 (ST6GAL2) was demonstrated to promote the tumorigenesis of FTC in vitro and in vivo. Furthermore, ST6GAL2 promoted tumorigenesis by inactivating the Hippo signaling pathway. Resveratrol is a native compound extracted from Vitis species, and many studies have confirmed its protective cardiovascular and antineoplastic effects. Here, we found that resveratrol can inhibit the tumorigenesis of FTC by suppressing the expression of ST6GAL2, thus further activating the Hippo pathway. In summary, this study further revealed the role of the ST6GAL2-Hippo signaling pathway in FTC tumorigenesis and indicated that resveratrol, a commonly found antineoplastic compound, could inhibit the tumorigenesis of FTC by regulating the abovementioned pathways.

  • CM082 enhances the efficacy of chemotherapeutic drug by inhibiting the drug efflux function of ABCG2
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-12-27
    Lejia Xu; Jiwei Huang; Jie Liu; Yun Xi; Zongheng Zheng; Kenneth K.W. To; Zhen Chen; Fang Wang; Yongming Zhang; Liwu Fu

    The overexpression of ATP-binding cassette (ABC) transporters is one of the important mechanisms of multidrug resistance (MDR). Some tyrosine kinase inhibitors (TKIs) such as CM082 might be the potential ABC transporter inhibitors, thus potentially reverse MDR. We used MTT assay to determine the cytotoxicity and reversal effect of CM082. Xenograft model was established to evaluate the reversal MDR efficacy in vivo. The intracellular accumulation and efflux of ABCG2 substrates were measured by Flow Cytometry. We investigated the binding sites of ABCG2 via the photo-labeling of ABCG2 with the [125I]-IAAP. RT-PCR and Western blot were utilized to analyze mRNA and protein expression. We found that CM082 could enhance the efficacy of substrate in ABCG2-overexpressing cells both in vitro and in vivo. Furthermore, CM082 significantly increased intracellular accumulation of ABCG2 substrates by inhibiting the efflux activity. CM082 stimulated ABCG2 ATPase activity and competed with [125I]-IAAP photolabeling of ABCG2 in a concentration-dependent manner. However, CM082 did neither alter ABCG2 expression at protein and mRNA levels nor inhibit VEGF downstream signaling of AKT and ERK. Further researches are encouraged to confirm whether CM082 concomitant with anticancer drugs of ABCG2 substrates could improve the clinical outcomes of cancer treatment in ABCG2 overexpression cancer patients.

    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-12-25
    Gwennaëlle C. Monnot; Amaia Martinez-Usatorre; Evripidis Lanitis; Silvia Ferreira Lopes; Wan-Chen Cheng; Ping-Chih Ho; Melita Irving; George Coukos; Alena Donda; Pedro Romero

    Therapy by adoptive transfer of ex vivo expanded tumour-infiltrating or genetically modified T cells may lead to impressive clinical responses. However, there is a need to improve in vivo persistence and functionality of the transferred T cells, in particular to face the highly immunosuppressive environment of solid tumours. Here, we investigate the potential of miR-155, a microRNA known to play an important role in CD8+ T cell fitness. We show that forced expression of miR-155 in tumour antigen-specific T cells improves the tumour control of B16 tumours expressing a low affinity antigen ligand. Importantly, miR-155-transduced T cells exhibit increased proliferation and effector functions, associated with a higher glycolytic activity independent of exogenous glucose. Altogether, these data suggest that miR-155 may optimize the antitumor activity of adoptively-transferred low-affinity TILs, in particular by rendering them more resistant to the glucose-deprived environment of solid tumours. Thus, transgenic expression of miR-155 may enable therapeutic targeting of self-antigen specific T cells in addition to neoantigen specific ones.

  • CXCR1 Expression to Improve Anti-Cancer Efficacy of Intravenously Injected CAR-Expressing NK Cells in Mice with Established Peritoneal Xenografts
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-12-24
    Yu Yang Ng; Johan CK. Tay; Shu Wang

    One reason underlying the failure of current chimeric antigen receptor (CAR) immune therapy to adequately treat solid tumors is insufficient tumor infiltration of CAR immune cells. To address the issue, we electroporated natural killer (NK) cells with two mRNA constructs encoding the chemokine receptor CXCR1 and a CAR targeting tumor-associated NKG2D ligands. The CXCR1-modified NK cells displayed increased migration towards tumor supernatants in vitro and augmented infiltration into human tumors in vivo in subcutaneous and intraperitoneal xenograft models. Most importantly, the cytotoxicity of the CAR-NK cells was not affected by CXCR1 transgene expression and the enhanced tumor trafficking following intravenous injection resulted in significantly increased antitumor responses in mice carrying established peritoneal ovarian cancer xenografts. Collectively, our findings suggest that the co-expression of CXCR1 and a CAR may provide a novel strategy to enhance therapeutic efficacy of NK cells against solid cancers.

  • Ginkgolic acid, a SUMO-1 inhibitor, inhibits the progression of oral squamous cell carcinoma by alleviating SUMOylation of SMAD4
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-12-14
    Ke Liu; Xinhuan Wang; Duo Li; Dongyang Xu; Dezhi Li; Zhiyong Lv; Dan Zhao; Wen-Feng Chu; Xiao-Feng Wang

    Small ubiquitin-related modifiers (SUMO) represent a class of ubiquitin-like proteins that are conjugated, like ubiquitin, by a set of enzymes to form cellular regulatory proteins, and play key roles in the control of cell proliferation, differentiation, and apoptosis. We found that GA can significantly reduce cell vitality in a dose- and time-dependent manner and can also accelerate cyto-apoptosis in both Tca8113 and Cal-27 cells. Migration and wound healing assays were executed to determine the anti-migration effect of GA in OSCC cell lines. GA represses TGF-β1-induced epithelial-mesenchymal transition (EMT) markers in OSCC cell lines. This investigation is the first evidence that GA suppresses TGF-β1-induced SUMOylation of SMAD4. We show that GA affects the phosphorylation of SMAD2/3 protein and the release of SMAD4. In the xenograft mouse model, the OSCC progression was reduced by GA, effectively suppressing the growth of tumors. In addition, siSMAD4 improved cell migration and viability, which was inhibited by GA in Tca8113 cells. GA suppresses tumorigenicity and tumor progression of OSCC through inhibition of TGF-β1-induced enhancement of SUMOylation of SMAD4. Thus, GA could be a promising therapeutic for OSCC.

  • Generation of a tumor-specific chemokine gradient using oncolytic vesicular stomatitis virus encoding CXCL9
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-12-14
    Elizabeth C. Eckert; Rebecca A. Nace; Jason M. Tonne; Laura Evgin; Richard G. Vile; Stephen J. Russell

    Genetically modified vesicular stomatitis virus (VSV) is an attractive agent for cancer treatment due to rapid intratumoral replication and observed clinical responses. While VSV selectively kills malignant cells and can boost antitumor immunity, limited induction of intratumoral immune infiltration remains a barrier to efficacy in some cancer models. Here we engineered the oncolytic VSV platform to encode the T cell chemokine CXCL9 which is known to mediate the recruitment of activated CD8+ cytotoxic T cells and CD4+ helper T cells, and demonstrates conserved protein function between mice and humans. Chemotactic activity of the virally encoded chemokine was confirmed in vitro. Intratumoral concentration of CXCL9 was shown to increase after VSV therapy in three different cancer models, but to a much greater degree after VSV-CXCL9 therapy as compared to VSV control viruses. Despite a steep chemokine gradient from the tumor to the bloodstream, tumor trafficking of adoptively transferred and endogenous T cells was not measurably increased following VSV-CXCL9 therapy. Our results indicate that oncolytic VSV infection promotes release of CXCL9 in the tumor microenvironment but further boosting of the functional chemokine gradient through virus engineering has little incremental impact on intratumoral immune cell infiltration in mouse and human tumor models.

  • A novel antitumor strategy through simultaneously inhibiting angiogenesis and complement by targeting VEGFA/PIGF and C3b/C4b
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-12-14
    Huiling Wang; Yiming Li; Gang Shi; Yuan Wang; Yi Lin; Qin Wang; Yujing Zhang; Qianmei Yang; Lei Dai; Lin Cheng; Xiaolan Su; Yang Yang; Shuang Zhang; Zhi Li; Jia Li; Yuquan Wei; Dechao Yu; Hongxin Deng

    Therapeutic antibodies targeting Vascular Endothelia Growth Factor (VEGF) have become a critical regimen for tumor therapy, but the efficacy of monotherapy is usually limited by drug resistance and multiple angiogenic mechanisms. Complement proteins are becoming potential candidates for cancer targeted therapy based its role to promote cancer progression and angiogenesis. However, the antitumor abilities of simultaneous VEGF and complement blockade were unknown. We generated humanized soluble VEGFR-Fc fusion protein (VID) binding VEGFA/PIGF and CR1-Fc fusion protein (CID) targeting C3b/C4b. Both VID and CID had good affinities to their ligands, and showed effective bioactivities. In vitro, angiogenesis effects induced by VEGF and hemolysis induced by complement were inhibited by VID and CID, respectively. Further, VID and CID confer a synergetic therapeutic effect in a colitis-associated colorectal cancer (CAC) model and orthotopic 4T1 breast cancer model. Mechanically, combination therapy inhibited tumor angiogenesis, cell proliferation and MDSCs infiltration in tumor microenvironment, and promoted tumor cell apoptosis. Our study offers a novel therapeutic strategy for anti-VEGF resistant tumors and chronic inflammation associated tumors.

  • A PTAL-miR-101-FN1 axis promotes EMT and invasion-metastasis in serous ovarian cancer
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-12-11
    Haihai Liang, Mengxue Yu, Rui Yang, Lu Zhang, Lijia Zhang, Di Zhu, Hongwei Luo, Yaozhen Hong, Tong Yu, Jian Sun, Hongli Shan, Yunyan Gu

    Long non-coding RNAs (lncRNAs) play vital roles in the metastasis and invasion of cancer cells. Systematic analysis of ovarian cancer (OvCa) expression profiles suggests that deregulation of lncRNA AC004988.1, designated promoting transition associated lncRNA (PTAL), is involved in OvCa progression. However, the underlying mechanism of PTAL in OvCa remains unknown. In this study, we showed that PTAL was significantly upregulated in mesenchymal subtype samples compared with epithelial subtype samples from TCGA serous OvCa data sets. PTAL expression was positively correlated with the expression of fibronectin1 (FN1), whereas PTAL and FN1 were negatively correlated with miR-101 expression in the mesenchymal OvCa samples. In addition, knockdown of PTAL inhibited cell migration and invasion, and blunted the progression of metastasis in vitro. Meanwhile, knockdown of PTAL increased the expression of miR-101 and subsequently inhibited the expression of FN1. Importantly, PTAL positively regulated the expression of FN1 through sponging of miR-101 and promoted OvCa cell metastasis by regulating epithelial-mesenchymal transition. Overall, our study demonstrates the role of PTAL as a miRNA sponge in OvCa and suggests that PTAL may be a potential target for preventing OvCa metastasis.

  • In vitro & molecular dynamic simulation study to explore physicochemical parameters for antibacterial peptide to become potent anticancer peptide
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-12-10
    Rui Ma, Sin Wa Wong, Lilin Ge, Chris Shaw, Shirley W.I. Siu, Hang Fai Kwok
  • Oncolytic Herpes Simplex Virus Prevents Premalignant Lesions from Progressing to Cancer
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-12-06
    Yanghee Woo, Vincent Reid, Kaitlyn J. Kelly, Diane Carlson, Zhenkun Yu, Yuman Fong

    Early detection and timely treatment of precancerous lesions are hallmarks of successful strategies to prevent deaths due to cancer. Oncolytic viruses are a group of promising anti-cancer agents with wide-ranging experimental and clinical efficacy against solid tumors. Previously, we have shown that NV1066, an oncolytic herpes simplex-1 virus encoding enhanced green fluorescent protein, selectively infects, replicates in, and kills various cancer types. In this study, we sought to determine whether this oncolytic agent can treat precancerous lesions to prevent cancer formation. Using an oral chemical carcinogenesis model in hamsters, we assessed the ability of NV1066 to infect precancerous and cancerous lesions. NV1066 consistently infected dysplastic cells, carcinoma in situ, and squamous cell carcinoma. Animals receiving an intramucosal injection of NV1066 for 7 weeks showed significantly fewer (3-fold) and smaller (4-fold) lesions compared to animals that did not receive viral treatment. Results indicate that infectivity might be dependent on the Herpes Simplex Virus-1 receptor, nectin-1. This study demonstrates that not only can NV1066 treat oral squamous cell carcinoma, but it can also infect and treat premalignant lesions, thus delaying cancer progression. Overall our study shows the potential of the oncolytic virus, NV1066 as a cancer prevention tool.

  • Natural killer cells; diverse functions in tumor immunity and defects in pre-neoplastic and neoplastic stages of tumorigenesis
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-11-29
    Anahid Jewett, Janko Kos, Kawaljit Kaur, Tahmineh Safaei, Christine Sutanto, Wuyang Chen, Paul Wong, Artin Keshishian Namagerdi, Changge Fang, Yuman Fong, Meng-Wei Ko

    Natural killer (NK) cells are the key immune effectors with the ability to mediate selection and differentiation of a number of different cancer stem cells/undifferentiated tumors via lysis, and secreted or membrane bound IFN-γ and TNF-α respectively, leading to curtailment of tumor growth and metastasis. In this review, we present an overview of our recent findings on the biology and significance of NK cells in selection/differentiation of stem-like tumors using in vitro and in vivo studies conducted in the humanized-BLT mice and those of cancer patients. In addition, we present current advances in NK cell expansion and therapeutic delivery, and discuss the utility of allogeneic super-charged NK cells in the treatment of cancer patients. Moreover, we discuss the potential loss of NK cell numbers and function at the neoplastic and pre-neoplastic stages of tumorigenesis in potential induction and progression of pancreatic tumors. Therefore, because of their indispensable role in targeting cancer stem-like/undifferentiated tumors, NK cells should be placed high in the armamentarium of tumor immunotherapy. Combination of allogeneic super-charged NK cells with other immunotherapeutic strategies such as oncolytic viruses, ADCC inducing antibodies, check point inhibitors, CAR-T, CAR-NK, and chemotherapeutic and radiotherapeutic strategies can be used for the ultimate goal of tumor eradication.

  • MiR-489-3p/SIX1 Axis Regulates Melanoma Proliferation and Glycolytic Potential
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-11-27
    Xuhui Yang, Xiang Zhu, Zhifeng Yan, Chenxi Li, Hui Zhao, Luyuan Ma, Deyu Zhang, Juan Liu, Zihao Liu, Nan Du, Qinong Ye, Xiaojie Xu
  • miR-424-5p Promotes Anoikis Resistance and Lung Metastasis by Inactivating Hippo signaling in Thyroid Cancer
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-11-13
    Xiaoli Liu, Yantao Fu, Guang Zhang, Daqi Zhang, Nan Liang, Fang Li, Changlin Li, Chengqiu Sui, Jinxi Jiang, Hongzhi Lu, Zihan Zhao, Gianlorenzo Dionigi, Hui Sun

    miR-424-5p has been widely identified to function as an oncomiR in multiple human cancer types. However, the biological function of miR-424-5p in distant metastasis of thyroid cancer, as well as the underlying mechanism remains not clarified yet. In the current study, miR-424-5p expression was elucidated in 10 paired fresh thyroid cancer tissues and thyroid cancer dataset from TCGA. Lung metastasis colonization models in vivo and functional assays in vitro were used to determine the role of miR-424-5p in thyroid cancer. Bioinformatics analysis, western blot, luciferase reporter and immunofluorescence assays were applied to identify the potential targets and underlying mechanism involved in functional role of miR-424-5p in lung metastasis of thyroid cancer. Here, we reported that miR-424-5p was upregulated in thyroid cancer, and overexpression of miR-424-5p significantly correlated with distant metastasis of thyroid cancer. Upregulating miR-424-5p promoted, while silencing miR-424-5p inhibited anoikis resistance in vitro, and lung metastasis in vivo. Mechanistic investigation further revealed that miR-424-5p promoted anoikis resistance and lung metastasis by inactivating Hippo signaling via simultaneously targeting WWC1, SAV1 and LAST2. Therefore, our results support the idea that miR-424-5p may serve as a potential therapeutic target in lung metastasis of thyroid cancer.

  • Oncolytic viruses for cancer therapy: barriers and recent advances
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-11-02
    Meijun Zheng, Jianhan Huang, Aiping Tong, Hui Yang

    Oncolytic viruses (OVs) are powerful new therapeutic agents in cancer therapy. With the first oncolytic virus (T-vec) obtaining US Food and Drug Administration approval, interest in OVs has been boosted greatly. Nevertheless, despite extensive research, oncolytic virotherapy has shown limited efficacy against solid tumors. Recent advances in viral retargeting, genetic editing, viral delivery platforms, tracking strategies, OV-based gene therapy, and combination strategies have the potential to broaden the applications of oncolytic virotherapy in oncology. In this review, we present several insights into the limitations and challenges of oncolytic virotherapy, describe the strategies mentioned above, provide a summary of recent preclinical and clinical trials in the field of oncolytic virotherapy, and highlight the need to optimize current strategies to improve clinical outcomes.

  • Exosomes carrying microRNA-155 target Forkhead box O3 of endothelial cells and promote angiogenesis in gastric cancer
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-10-31
    Zhengyang Zhou, Haiyang Zhang, Ting Deng, Tao Ning, Rui Liu, Dongying Liu, Ming Bai, Guoguang Ying, Yi Ba

    Gastric cancer (GC) has a poor prognosis due to its relentless proliferation and metastasis. One of the reasons for this plight is that formidable angiogenesis ability of GC. Considering the important role of cancer exosomes as carriers and communicators in tumor microenvironment, we explored the role of exosome-miRNA in regulating angiogenesis. Western blotting and real-time qPCR were used to measure the protein and mRNA levels of the miRNA target gene. To detect changes in cellular biological functions, we pretreated HUVECs that were severally cocultured with GC-derived exosomes, and transfected with different miRNAs directly. And we used the mouse xenograft model to verify the effect of miR-155 on angiogenesis of GC tissues in vivo. Our study confirmed that miR-155, as a driver of angiogenesis, encapsulated by exosomes from GC can enhance the generation of new vessels for GC in vitro through inhibiting the expression of FOXO3a protein, which led to the progression of GC. Therefore, miR-155 is probable to become a potential biomarker for the detection of migration and angiogenesis of GC, and serves as a novel target for anti-angiogenesis therapy.

  • GBM-targeted oHSV armed with matrix metalloproteinase 9 enhances anti-tumor activity and animal survival
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-10-24
    Paola Sette, Nduka Amankulor, Aofei Li, Marco Marzulli, Daniela Leronni, Mingdi Zhang, William F. Goins, Balveen Kaur, Chelsea Bolyard, Timothy P. Cripe, Jianhua Yu, E. Antonio Chiocca, Joseph C. Glorioso, Paola Grandi

    The use of mutant strains of oncolytic herpes simplex virus (oHSV) in early phase human clinical trials for the treatment of glioblastoma multiforme (GBM) has proven safe, but limited efficacy suggests that more potent vector designs are required for effective GBM therapy. Inadequate vector performance may derive from poor intratumoral vector replication and limited spread to uninfected cells. Vector replication may be impaired by mutagenesis strategies to achieve vector safety and intratumoral virus spread may be hampered by vector entrapment in the tumor-specific extracellular matrix (ECM) that in GBM is composed primarily of type IV collagen. In this report, we armed our previously described EGFRvIII-targeted, neuronal microRNA-sensitive oHSV with a matrix metalloproteinase (MMP9) to improve intratumoral vector distribution. We show that vector-expressed MMP9 enhanced therapeutic efficacy and long-term animal survival in a GBM xenograft model.

  • Enhanced therapeutic efficacy of a novel oncolytic herpes simplex virus type 2 encoding an antibody against programmed cell death 1
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-10-23
    Yujie Zhu, Xiao Hu, Lin Feng, Zhenrong Yang, Lulin Zhou, Xinchun Duan, Shujun Cheng, Wen Zhang, Binlei Liu, Kaitai Zhang

    The efficacy of immune checkpoint blockade therapy against immunologically ‘cold’ tumors can be enhanced by applying the checkpoint inhibitors in combination with oncolytic viruses. Alternatively, the oncolytic virus construct has been modified to express factors that boost oncolytic virus function. We engineered a novel oncolytic herpes simplex virus 2 encoding an anti-human PD-1 monoclonal antibody (oHSV2-aPD1). This virus resulted in the detectable expression of a functional monoclonal antibody against human PD-1 by infecting eukaryotic cells. Therapeutic efficacy of oHSV2-aPD1 proved superior to unmodified oncolytic HSV2 treatment or PD-1 blockade alone and as effective as their combination in the poorly immunogenic melanoma models. Additionally, local oHSV2-aPD1 treatment induced a durable antitumor response and activated many immune effector cells and molecules both in the tumor microenvironment and in the systemic immune system. This provides support for combinatorial strategies involving local administration of an oncolytic HSV2 expressing a PD-1 inhibitor.

  • High-affinity DARPin allows targeting of measles virus to glioblastoma multiforme in combination with protease targeting without loss of potency.
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-10-23
    Jan R.H. Hanauer, Vivian Koch, Ulrich M. Lauer, Michael D. Mühlebach

    Measles virus (MeV) is naturally cytolytic by extensive cell-to-cell fusion. Vaccine-derived MeV is toxic for cancer cells and is clinically tested as oncolytic virus. To combine the potential of MeV with enhanced safety, different targeting strategies have been described. We generated a receptor-targeted MeV by using receptor-blind viral attachment protein genetically fused to Designed Ankyrin Repeat Protein (DARPin) binding domains specific for the epidermal growth factor receptor (EGFR). To reduce on-target toxicity for EGFR+ healthy cells, an engineered viral fusion protein activatable by tumor-associated matrix metalloproteases (MMPs) was used for additional protease targeting. The dual-targeted virus replicated exclusively on EGFR+/MMP+ tumor cells, but was safe on healthy EGFR+ target cells, primary human keratinocytes. Nevertheless, glioblastoma and other tumor cells were efficiently killed by all targeted viruses, although replication and oncolysis were slower for protease-targeted MeV. In vivo, efficacy of EGFR-targeted MeV was virtually unimpaired, whereas also dual-targeted MeV showed significant intra-tumoral spread, efficacy, and could be armed with a prodrug convertase. The use of DARPin-domains resulted in potent EGFR-targeted MeV and for the first time effective dual retargeting of an oncolytic virus, further enhancing tumor selectivity. Together with powerful cell-toxic genes, the application as highly tumor-specific platform is promising.

  • Dual Isotope SPECT imaging with NIS Reporter Gene and Duramycin To Visualize Tumor Susceptibility to Oncolytic Virus Infection
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-10-10
    Lianwen Zhang, Lukkana Suksanpaisan, Huailei Jiang, Timothy R. DeGrado, Stephen J. Russell, Ming Zhao, Kah-Whye Peng

    Noninvasive dual imaging methods that provide an early readout on tumor permissiveness to virus infection and tumor cell death could be valuable in optimizing development of oncolytic virotherapies. Here, we have used the sodium iodide symporter (NIS) and 125I radiotracer to detect infection and replicative spread of an oncolytic Vesicular Stomatitis Virus (VSV) in VSV susceptible (MPC-11 tumor) versus resistant (CT26 tumor) tumors in Balb/c mice. In conjunction, tumor cell death was imaged simultaneously using 99mTc-duramycin that binds phosphatidylethanolamine in apoptotic and necrotic cells. Dual isotope SPECT/CT imaging showed areas of virus infection (NIS and 125I), which overlapped well with areas of tumor cell death (99mTc-duramycin imaging) in susceptible tumors. Multiple infectious foci arose early in MPC-11 tumors, which rapidly expanded throughout the tumor parenchyma over time. There was a dose dependent increase in numbers of infectious centers and 99mTc-duramycin positive areas with viral dose. In contrast, NIS or duramycin signals were minimal in VSV resistant CT26 tumors. Combinatorial use of NIS and 99mTc-duramycin SPECT imaging for simultaneous monitoring of OV spread, and the presence or absence of treatment associated cell death could be useful to guide development of combination treatment strategies to enhance therapeutic outcome.

  • An Engineered AAV6 Based Vaccine Induces High Cytolytic Anti-Tumor Activity by Directly Targeting Dendritic Cells and Improves Antigen Presentation
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-10-07
    K. Krotova, A. Day, G. Aslanidi

    We have previously shown that an AAV6-based vaccine generates high levels of antigen-specific CD8+ T-cells. Further modifications described here led to significantly increased levels of antigen-specific CD8+ and CD4+ T-cells, enhanced formation of memory cells and superior antigen-specific killing capacity in a murine model. By tracking reporter gene positive dendritic cells, we showed that they were directly targeted with modified AAV6 in vivo. Our vaccine’s anti-cancer potential was evaluated with the antigen ovalbumin against a B16F10 melanoma cell line stably expressing ovalbumin. The vaccination showed superior protection in a murine model of metastatic melanoma. The vaccination significantly delayed solid tumor growth, but did not completely prevent tumor development. We show that tumors in immunized mice escaped vaccine-induced killing by losing ovalbumin expression. The vaccine induced massive tumor infiltration with NK and CD8+ T-cells with up-regulated PD-1 expression. Thus, a combination of vaccination with anti-PD-1 antibodies demonstrated significant improvement in the treatment efficacy. To summarize, we showed that a bioengineered AAV6-based vaccine elicits strong and long-lasting cellular and humoral responses against an encoded antigen. To increase AAV vaccine efficiency and mitigate tumor escape through antigen loss we intend to target several antigens in combination with treatments targeting the tumor microenvironment.

  • Targeting histone methyltransferase DOT1L by a novel psammaplin A analog inhibits growth and metastasis of triple-negative breast cancer
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-10-01
    Woong Sub Byun, Won Kyung Kim, Hae Ju Han, Hwa-Jin Chung, Kyungkuk Jang, Han Sun Kim, Sunghwa Kim, Donghwa Kim, Eun Seo Bae, Sunghyouk Park, Jeeyeon Lee, Hyeung-geun Park, Sang Kook Lee

    Triple-negative breast cancer (TNBC) is the most intractable cancer in woman with high risk of metastasis. While hyper-methylation of histone H3 catalyzed by disruptor of telomeric silencing 1-like (DOT1L), a specific methyltransferase for histone H3 lysine residue 79 (H3K79), is reported as a potential target for TNBCs, early developed nucleoside-type DOT1L inhibitors are not sufficient for effective inhibition of growth and metastasis of TNBC cells. We found that triple-negative breast cancer (TNBC) cells had a high expression level of DOT1L and low expression level of E-cadherin compared to the normal breast epithelial cell and non-TNBC cells. Here, a novel psammaplin A analog (PsA-3091) exhibited a potent inhibitory effect of DOT1L-mediated H3K79 methylation. Consistently, PsA-3091 also significantly inhibited the proliferation, migration, and invasion of TNBC cells along with the augmented expression of E-cadherin, and the suppression of N-cadherin, ZEB1, and vimentin expression. In an orthotopic mouse model, PsA-3091 effectively inhibited lung metastasis and tumor growth by the regulation of DOT1L activity and EMT biomarkers. Together, we report here a new template of DOT1L inhibitor and suggest that targeting DOT1L-mediated H3K79 methylation by a novel psammaplin A analog may be a promising strategy for the treatment of metastatic breast cancer patients.

  • Syncytia formation in oncolytic virotherapy
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-10-01
    Chase Burton, Eric Bartee

    Oncolytic virotherapy uses replication competent virus as a means of treating cancer. While this field has shown great promise as a viable treatment method, the limited spread of these viruses throughout the tumor micro-environment remains a major challenge. To overcome this issue, researchers have begun looking at syncytia formation as a novel method of increasing viral spread. Several naturally occurring fusogenic viruses have been shown to possess strong oncolytic potential and have since been studied to gain insight into how this process benefits oncolytic virotherapy. While these naturally fusogenic viruses have been beneficial, there are still challenges associated with their regular use. Because of this, engineered/recombinant fusogenic viruses have also been created which enhance non-fusogenic oncolytic viruses with the beneficial property of syncytia formation. The purpose of this review is to examine the existing body of literature on syncytia formation in oncolytics and offer direction for potential future studies.

  • Intravenous injections of a rationally selected oncolytic herpes virus as a potent virotherapy for hepatocellular carcinoma
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-10-01
    Yong Luo, Chaolong Lin, Wenfeng Ren, Fei Ju, Zilong Xu, Huiling Liu, Zeng Yu, Jun Chen, Jun Zhang, Pingguo Liu, Chenghao Huang, Ningshao Xia

    As a clinical setting in which novel treatment options are urgently needed, hepatocellular carcinoma (HCC) exhibits intriguing opportunities for oncolytic virotherapy. Here, we report the rational generation of a novel HSV-1-based oncolytic vector for targeting HCC, named Ld0-GFP, which was derived from oncolytic ICP0-null virus (d0-GFP), had fusogenic phenotype and was a novel killer against HCC as well as other types of cancer cells. Compared with d0-GFP, Ld0-GFP exhibited superior cancer cell killing ability in vitro and in vivo. Ld0-GFP targets a broad spectrum of HCC cells and can result in significantly enhanced immunogenic tumor cell death. Intratumoral and intravenous injections of Ld0-GFP showed effective antitumor capabilities in multiple tumor models, leading to increased survival. We speculated that more active cell killing capability of oncolytic virus and enhanced immunogenic cell death may lead to better tumor regression. Additionally, Ld0-GFP had improved safety profile, showing reduced neurovirulence and systemic toxicity. Ld0-GFP virotherapy could offer a potentially less toxic, more effective option for both local and systemic treatment of HCC. This approach also provides novel insights toward ongoing efforts to develop an optimal oncolytic vector for cancer therapy.

  • Calcium influx caused by ER stress inducers enhances oncolytic adenovirus Enadenotucirev replication and killing through PKCα activation
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-09-28
    William K. Taverner, Egon J. Jacobus, John Christianson, Brian Champion, Adrienne W. Paton, James C. Paton, Weiheng Su, Ryan Cawood, Len W. Seymour, Janet Lei-Rossmann
  • CBX7 inhibits cell growth and motility and induces apoptosis in cervical cancer cells
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-09-24
    Rong Li, Lu Ding, Ping Tian, Yan Wang, Jing Wang, Qi Yan, Ning Tao, Li Ning, Xin Lin, Jiwen Liu, Cailing Ma

    The chromobox protein homolog 7 (CBX7), one member of the polycomb group family, has been characrized to mainly play a tumor suppressive role in human malignant neoplasias. Moreover, downregulation of CBX7 is correlated with poor prognosis and aggressiveness in a variety of human cancers. However, the biological functions and role of CBX7 in cervical cancer have not been elucidated. In the present study, we explore whether CBX7 exerts its tumor suppressive function in cervical cancer. To achieve this goal, molecular approaches were used to upregulate the expression of CBX7 or downregulation of CBX7 in cervical cancer cell lines. We observed that overexpression of CBX7 inhibited cell growth and induced apoptosis in cervical cancer cells. CBX7 overexpression retarded cell migration and invasion in cervical cancer cells. In line with this, downregulation of CBX7 promoted cell growth and migration as well as invasion in cervical cancer cells. Our findings suggest that CBX7 might be a tumor suppressor and could be a potential target in cervical cancer.

  • STING Restricts Oncolytic HSV Replication and Spread in Resistant Malignant Peripheral Nerve Sheath Tumors but is Dispensable for Basal Interferon Stimulated Gene Upregulation.
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-09-16
    Joel M. Lee, Mohammed Ghonime, Kevin A. Cassady

    Malignant peripheral nerve sheath tumors (MPNSTs) are an aggressive soft-tissue sarcoma amenable only to surgical resection.1 Oncolytic herpes simplex viruses (oHSVs) are a promising experimental therapy. We previously showed that basal IFN and NF-ĸB signaling upregulate interferon stimulated gene (ISG) expression and restrict efficient viral infection and cell-to-cell spread in ∼50% of tested MPNSTs.2 Stimulator of Interferon Genes (STING) integrates DNA sensor activity and mediates downstream interferon signaling in infected cells. We sought to identify STING’s role in oHSV resistance and contribution to basal ISG upregulation in MPNSTs. We now show that the level of STING activity in human MPNST cell lines is predictive of oHSV sensitivity, and that resistant cell lines have intact mechanisms for detection of cytosolic dsDNA. Furthermore, we show that STING downregulation renders MPNSTs more permissive to oHSV infection and cell-to-cell spread. While next-generation viruses can exploit this loss of STING activity, first-generation viruses remain restricted. Finally, STING is not integral to the previously-observed basal ISG upregulation—indicating that other pathways contribute to basal IFN signaling in resistant MPNSTs. These data broaden our understanding of the intrinsic pathways in MPNSTs, their role in oHSV resistance, and offer potential targets to potentiate oncolytic virus activity.

  • Crosstalk between let-7a-5p and BCL-xL in the initiation of toxic autophagy in lung cancer
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-09-10
    Shuyin Duan, Junxia Li, Jiaqi Tian, Haoyu Yin, Qingfeng Zhai, Yongjun Wu, Sanqiao Yao, Lin Zhang

    Autophagy is essential for cellular metabolism and plays pivotal roles in carcinogenesis, while excessive autophagy induces toxicity and cell death. Our previous studies have suggested that let-7a-5p/BCL-xL might regulate autophagy in lung cancer, but the regulatory mechanism is unclear. The central goal of the study was to figure out the role of let-7a-5p/BCL-xL in the initiation of autophagy and its effect on the migration, invasion, and proliferation of A549 cells as well as its therapeutic potential in lung cancer. Basing on the genome-wide expression profiles of lung cancer, BCL-xL and let-7a-5p were found to be dysregulated and negatively correlated in lung adenocarcinoma, which was associated with the survival of lung cancer. The crosstalk between BCL-xL and let-7a-5p was then investigated using dual-luciferase reporter assay and was found to suppress the migration and invasion of A549 cells. Further, we found that the crosstalk between BCL-xL and let-7a-5p could lead to toxic autophagy and cell death through activating the PI3K signaling pathway, which was independent of apoptosis or pyroptosis. These findings indicate that let-7a-5p is a sensitive initiator for toxic autophagy in A549 lung cancer cells and is an appealing target for lung cancer therapy.

  • Inflammatory microenvironment contributes to stemness properties and metastatic potential of hepatocellular carcinoma via NF-κB/miR-497/SALL4 axis
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-09-10
    Bixing Zhao, Yingchao Wang, Xionghong Tan, Kun Ke, Xiaoyuan Zheng, Fei Wang, Shubing Lan, Naishun Liao, Zhixiong Cai, Yingjun Shi, Youshi Zheng, Yongping Lai, Lili Wang, Qin Li, Jingfeng Liu, Aimin Huang, Xiaolong Liu

    Increasing evidences have demonstrated the essential roles of inflammatory microenvironment on tumorigenesis and tumor progression. Some cancer cells in tumor maintain typical stemness properties and with capacity of self-renewal are thought to be crucial for the initiation and maintenance of tumours as well as their metastasis. Although both inflammatory microenvironment and stemness properties played crucial roles in tumor initiation and development, currently it is still unclear whether and how the inflammatory microenvironment promotes cancer stemness properties. Here, we show the first evidence that the inflammatory microenvironment promote stemness properties and metastatic potential of hepatocellular carcinoma (HCC) via NF-κB/miR-497/SALL4 axis. We discover that miR-497 directly targets SALL4 and negatively regulates its expression, and further inhibits the self-renewal and metastasis of HCC; more importantly, inflammatory factor TNFα inhibits the expression of miR-497 via NF-kB mediated negative transcriptional regulation, and simultaneously up-regulates the expression of SALL4 and promotes self-renewal and metastasis phenotype of HCC cells. Moreover, lower expression of miR-497 is significantly associated with poor prognosis in HCC patients. Taken together, our findings not only revealed a novel signaling pathway (NF-κB/miR-497/SALL4 axis) to connect inflammation with stemness properties and clarified the molecular mechanisms underlying the inflammation-mediated self-renewal and metastasis phenotypes, but also provided novel molecular targets for developing new anticancer strategies.

  • Emerging role of sperm-associated antigen 6 gene in microtubule function of cell and cancer
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-09-10
    Da-Fang Zheng, Qi Wang, Jing-Ping Wang, Zheng-Qi Bao, Shi-Wu Wu, Li Ma, Da-Min Chai, Z Peter Wang, Yi-Sheng Tao

    Accumulated evidence shows that sperm-associated antigen 6 (SPAG6) gene has multiple biological functions. It maintains the normal function of a variety of cells including Ciliary/flagellar biogenesis and polarization, neurogenesis and neuronal migration. Moreover, SPAG6 is found to be critically involved in auditory transduction and fibroblast life cycle. Furthermore, SPAG6 plays an essential role in immuno-regulation. Notably, SPAG6 has been demonstrated to participate in the occurrence and progression of a variety of human cancers. New evidence shows that SPAG6 gene regulates tumor cell proliferation, apoptosis, invasion and metastasis. Therefore, in this review, we describe the physiological function and mechanism of SPAG6 in human normal cells and cancer cells. We also highlight that SPAG6 gene may be an effective biomarker for the diagnosis of human cancer. Taken together, targeting SPAG6 could be a novel strategy for the treatment of human diseases including cancer.

  • Computationally Guided Design Of Single-Chain Variable Fragment Improves Specificity Of Chimeric Antigen Receptors
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-08-31
    Andrey Krokhotin, Hongwei Du, Koichi Hirabayashi, Konstantin Popov, Tomohiro Kurokawa, Xinhui Wan, Soldano Ferrone, Gianpietro Dotti, Nikolay V. Dokholyan

    CAR-T cell based immunotherapy of malignant disease relies on the specificity and association constant of single-chain variable fragments (scFv). The latter are synthesized from parent antibodies by fusing their light (VL) and heavy (VH) chain variable domains into a single chain using a flexible linker peptide. The fusion of VL and VH domains can distort their relative orientation, thereby compromising specificity and association constant of scFv, and reducing the lytic efficacy of CAR-T cells. Here, we circumvent the complications of domains’ fusion by designing scFv mutants that stabilize interaction between scFv and its target thereby rescuing scFv efficacy. We employ an iterative approach, based on structural modeling and mutagenesis driven by computational protein design. To demonstrate the power of this approach, we use the scFv derived from an antibody specific to a human leukocyte antigen A2 (HLA-A2)-HER2 derived peptide complex. While the parental antibody is highly specific to its target, the scFv showed reduced specificity. Using our approach, we design mutations into scFv that restore specificity of the original antibody.

  • The role of adaptor protein CARD9 in colitis-associated cancer
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-08-30
    Xiaoming Zhong, Bin Chen, Min Liu, Zhiwen Yang

    The adaptor protein CARD9 plays an important role in anti–fungal immunity responses, linking detection of fungi by surface receptors to activation of the transcription factor nuclear factor kappa-B (NF–κB). Recent studies indicate that CARD9 also plays different but vital roles during the development of colitis–associated colorectal cancer (CAC). This review will summarize the current understanding of CARD9 functions in CAC, and discuss its potentially carcinogenic mechanisms.

  • The Discordance of Gene Mutations between Circulating Tumor Cells and Primary/metastatic Tumor
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-08-29
    Qi Wang, Lanbo Zhao, Lu Han, Xiaoqian Tuo, Sijia Ma, Yiran Wang, Xue Feng, Dongxin Liang, Chao Sun, Qing Wang, Qing Song, Qiling Li

    Circulating tumor cells (CTCs) are an important part in the field of “liquid biopsy”. However, major questions remain to be answered whether the mutations in the CTCs represent the mutations in primary tumor tissue and metastatic tumors. We compared the genetic mutations between CTCs and their matched tumors, and extracted data on the heterogeneity of the mutational status in CTCs and the change in mutations of CTCs before and during treatment. For mutations detected in single genes, we calculated the concordance of the mutations between the CTCs and primary tumor tissue. For mutations detected in multiple genes, we calculated the concordance of the mutations between the CTCs and primary/metastatic tumor tissue. The heterogeneity of the mutational status is clear present in CTCs. For mutations detected in a single gene, the overall concordance of mutations is 53.05%. For mutations detected in multiple genes, the concordance of mutations is extremely different. The heterogeneity of the mutational status existed in single CTCs, and the mutational status of CTCs were discordance with that of tumor tissue.

  • OCT4B1 Promoted EMT and Regulated the Self-renewal of Cancer Stem Cells (CSCs) in Colorectal Cancer: Effects Associated with the Balance of miR-8064/PLK1
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-08-28
    Jun-min Zhou, Shui-qing Hu, Hang Jiang, Yi-lin Chen, Ji-hong Feng, Zheng-quan Chen, Kun-ming Wen

    Cancer stem cells (CSCs) are the main cause of tumor generation, recurrence, metastasis, and therapy failure in various malignancies including colorectal cancer (CRC). Accumulating evidence suggests that tumor cells can acquire CSC characteristics through the epithelial-mesenchymal transition (EMT) process. However, the molecular mechanism of CSCs remains unclear. OCT4B1 is a transcript of OCT4, which is initially expressed in embryonic stem and carcinoma cells and is involved in the regulation and maintenance of an undifferentiated state of stem cells. In this study, three-dimensional (3D) microspheres were confirmed as CRC stem cells. Compared with that of parental cells, their self-renewal ability was significantly increased, and OCT4B1 expression was increased and promoted the EMT process. The knockdown of OCT4B1 decreased the self-renewal of CSCs and reversed EMT. Moreover, OCT4B1 induced the expression of PLK1, which is a key regulator of EMT in tumor cells. Further examination showed that OCT4B1 regulated the miR-8064/PLK1 balance to exert its function. Taken together, our data suggest that OCT4B1 may be involved in regulating the self-renewal of colorectal CSCs through EMT, which is at least partially due to the miR-8064/PLK1 balance. This study indicates that OCT4B1 is a potential therapeutic target for CRC by targeting CSCs.

  • Combination Therapy with Reovirus and ATM Inhibitor Enhances Cell Death and Virus Replication in Canine Melanoma
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-08-28
    Masaya Igase, Shusaku Shibutani, Yosuke Kurogouchi, Noriyuki Fujiki, Chung Chew Hwang, Matt Coffey, Shunsuke Noguchi, Yuki Nemoto, Takuya Mizuno

    Oncolytic virotherapy using reovirus is a promising new anti-cancer treatment with potential for use in humans and dogs. Because reovirus monotherapy shows limited efficacy in human and canine cancer patients, the clinical development of a combination therapy is necessary. To identify candidate components of such a combination, we screened a 285-compound drug library for those that enhanced reovirus cytotoxicity in a canine melanoma cell line. Here, we show that exposure to an inhibitor of the ataxia telangiectasia mutated protein (ATM) enhances the oncolytic potential of reovirus in 5 of 6 tested canine melanoma cell lines. Specifically, the ATM inhibitor potentiated reovirus replication in cancer cells along with promoting the lysosomal activity, resulting in an increased proportion of caspase-dependent apoptosis and cell cycle arrest at G2/M compared to those observed with reovirus alone. Overall, our study suggests that the combination of reovirus and the ATM inhibitor may be an attractive option in cancer therapy

  • Parallel comparison of 4-1BB or CD28 co-stimulated CD19-targeted chimeric antigen receptor-T cells for B-cell non-Hodgkin lymphoma
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-08-28
    Zhitao Ying, Ting He, Xiaopei Wang, Wen Zheng, Ningjing Lin, Meifeng Tu, Yan Xie, Lingyan Ping, Chen Zhang, Weiping Liu, Lijuan Deng, Feifei Qi, Yanping Ding, Xin-an Lu, Yuqin Song, Jun Zhu

    CD19-targeted chimeric antigen receptor-T (CAR-T) cells with CD28 or 4-1BB (28z CAR-T and BBz CAR-T) have shown great promise to treat relapsed or refractory (r/r) B cell non-Hodgkin lymphoma (B-NHL). However, comparison of their clinical outcomes has never been reported. This study investigated their efficacy and adverse events in B-NHL therapy. Six patients with r/r B-NHL were initially enrolled and infused with 28z or BBz CAR-T cells at the dose of 0.75-5×105/kg. These CAR-T cells showed similar antitumor efficacies, with a complete response (CR) rate of 67% within three months. BBz CAR-T was well tolerated. However, severe cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome occurred in the 28z CAR-T cohort, resulting in the termination of further evaluation of 28z CAR-T. Three more patients were enrolled to in-depth investigate BBz CAR-T cells at an escalated dose (1×106/kg). All cases achieved CR within three months and only grade 1/2 adverse events occurred. This study suggests that 4-1BB is more beneficial for the clinical performance of CAR-T cells than CD28 in CD19-targeted B-NHL therapy, at least under our manufacturing process.

  • ROS/KRAS/AMPK signaling contributes to gemcitabine-induced stem-like cell properties in pancreatic cancer
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-08-09
    Hengqiang Zhao, Shihong Wu, Hehe Li, Qingke Duan, Zhengle Zhang, Qiang Shen, Chunyou Wang, Tao Yin

    Poor prognosis in pancreatic cancer (PanCa) is partially due to chemoresistance to gemcitabine (GEM). Glucose metabolism has been revealed to contribute to the therapeutic resistance and pluripotent state of PanCa cells. However, few studies have focused on the effects of GEM on cancer cell metabolism, stemness of tumor cells, and molecular mechanisms that critically influence PanCa treatment. We demonstrated that GEM treatment induces metabolic reprogramming, reducing mitochondrial oxidation and upregulating aerobic glycolysis, and promotes stemlike behaviors in cancer cells. Inhibiting aerobic glycolysis suppresses cancer cell stemness and strengthens GEM’s cytotoxicity. GEM-induced metabolic reprogramming is KRAS-dependent, as knockdown of KRAS reverses the metabolic shift. GEM-induced metabolic reprogramming also activates AMP-activated protein kinase (AMPK), which promotes glycolytic flux and cancer stemness. In addition, GEM-induced reactive oxygen species (ROS) activate the KRAS/AMPK pathway. This effect was validated by introducing exogenous hydrogen peroxide (H2O2). Taken together, these findings reveal a counterproductive GEM effect during PanCa treatment. Regulating cellular redox, targeting KRAS/AMPK signaling, or reversing metabolic reprogramming might be effective approaches to eliminate cancer stem cells (CSCs) and enhance chemosensitivity to GEM to improve the prognosis of PanCa patients.

  • Exosomal Leucine-rich-alpha2-glycoprotein 1 Derived from Non-Small-Cell Lung Cancer Cells Promotes Angiogenesis via Transforming-growth-factor-beta Signal Pathway
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-08-07
    Zifan Li, Chao Zeng, Qiaohong Nong, Feihu Long, Jixian Liu, Zhimin Mu, Baokun Chen, Da Wu, Hao Wu

    Non-small cell lung cancer (NSCLC) is a major cause for cancer-related deaths around the globe, partially due to the frequent recurrence and metastasis. Leucine-rich-alpha2-glycoprotein 1 (LRG1) is reportedly upregulated in several cancers including NSCLC; however, its functions in NSCLC remain elusive. We used quantitative real-time PCR and western blot assays to evaluate the expression patterns of LRG1 in tumor tissues collected from NSCLC patients as well as NSCLC cell lines, and examined the effects of LRG1 on the proliferation, migration, and invasion of NSCLC cells. Further, we isolated exosomes from the blood of NSCLC patients as well as NSCLC cell cultures, and assessed the impact of exosome exposure on the angiogenic capacities of human umbilical vein endothelial cells. LRG1 was upregulated in NSCLC tissues and cells, and induced an enhancement of NSCLC cell proliferation, migration, and invasion. In addition, LRG1 was enriched in the exosomes derived from NSCLC tissue/cells, and mediated a proangiogenic effect via the activation of transforming growth factor (TGF)-β pathway. Exosomal LRG1 derived from NSCLC cells promotes angiogenesis via TGF-β signaling and possesses the potential of a therapeutic target in NSCLC treatment.

  • The miR-195 axis regulates chemoresistance through TUBB and lung cancer progression through BIRC5
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-08-06
    Xiaojie Yu, Yiqiang Zhang, Binggen Wu, Jonathan M. Kurie, Alexander Pertsemlidis

    Chemoresistance and metastasis are the major reasons for NSCLC treatment failure and patient deaths. We and others have shown that miR-195 regulates the sensitivity of NSCLC to microtubule-targeting agents (MTAs) in vitro and in vivo and that miR-195 represses the migration and invasion of NSCLC cells in vitro. However, the relationship between miR-195 and microtubule structure and function and whether miR-195 represses NSCLC metastasis in vivo remain unknown. We assessed the correlation between tumor levels of TUBB and patient survival, the effect of TUBB on drug response, and the effect of miR-195 on migration, invasion and metastasis in vitro and in vivo. We found that miR-195 directly targets TUBB, that knock-down of TUBB sensitizes cells to MTAs while over-expression confers resistance, that high expression of TUBB is correlated with worse survival of lung adenocarcinoma, that TUBB is also regulated by CHEK1, which has been shown to regulate chemoresistance, and that miR-195 targets BIRC5 to repress migration and invasion in vitro and metastasis in vivo. Our findings highlight the relevance of the miR-195/TUBB axis in regulating the response of NSCLC to MTAs and the importance of the miR-195/BIRC5 axis in regulating NSCLC metastasis.

  • Coxsackievirus Type B3 is A Potent Oncolytic Virus against KRAS-Mutant Lung Adenocarcinoma
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-07-23
    Haoyu Deng, Huitao Liu, Tanya de Silva, YuanChao Xue, Yasir Mohamud, Chen Seng Ng, Junyan Qu, Jingchun Zhang, William Jia, William W. Lockwood, Honglin Luo

    KRAS-mutant (KRASmut) lung adenocarcinoma is a refractory cancer without available targeted therapy. The current study explored the possibility to develop coxsackievirus B3 (CVB3) as an oncolytic agent for the treatment of KRASmut lung adenocarcinoma. In cultured cells, we discovered that CVB3 selectively infects and lyses KRASmut lung adenocarcinoma cells (A549, H2030, and H23), while sparing normal lung epithelial cells (Primary, BEAS2B, HPL1D, and 1HAEo) and EGFRmut lung adenocarcinoma cells (HCC4006, PC9, H3255, and H1975). Using stable cells expressing a single driver mutation of either KRASG12V or EGFRL858R in normal lung epithelial cells (HPL1D), we further showed that CVB3 specifically kills HPL1D-KRASG12V cells with minimal harm to HPL1D-EGFRL858R and control cells. Mechanistically, we demonstrated that aberrant activation of ERK1/2 and compromised type-I interferon immune response in KRASmut lung adenocarcinoma cells serve as key factors contributing to the sensitivity to CVB3-induced cytotoxicity. Lastly, we conducted in vivo xenograft studies using two immunocompromised mouse models. Our results revealed that intratumoral injection of CVB3 results in a marked tumor regression of KRASmut lung adenocarcinoma in both NSG and NOD-SCID xenograft models. Together, our findings suggest that CVB3 is an excellent candidate to be further developed as a targeted therapy for KRASmut lung adenocarcinoma.

  • Programmable nuclease-based integration into novel extragenic genomic safe harbor identified from Korean population-based CNV analysis
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-07-23
    Eun-Seo Lee, Sanghoon Moon, Kwaku Dad Abu-Bonsrah, Yun Kyoung Kim, Mi Yeong Hwang, Young Jin Kim, Seokjoong Kim, Nathaniel S. Hwang, Hyongbum Henry Kim, Bong-Jo Kim

    Here, we found two genomic safe harbor (GSH) candidates from chromosome 3 and 8, based on a large-scale population-based cohort data from 4,694 Koreans by CNV analysis. Furthermore, estimated genotype of these CNVRs was validated by quantitative real-time PCR (qRT-PCR), and epidemiological data examined no significant genetic association between diseases/traits and two CNVRs. After screening the GSH candidates by in silico approaches, we designed TALEN pairs to integrate eGFP expression cassette into human cell lines in order to confirm the functionality of GSH candidates at in vitro setting. As a result, transgene insertion into one of the two loci using TALEN showed robust transgene expression comparable to that into AAVS1 site without significantly perturbing neighboring genes. Changing the promoter or cell type did not noticeably disturb this trend. Thus, we could validate two CNVRs as a site for effective and safe transgene insertion in human cells.

  • B7-H3 as a novel CAR-T therapeutic target for glioblastoma
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-07-23
    Xin Tang, Shasha Zhao, Yang Zhang, Yuelong Wang, Zongliang Zhang, Meijia Yang, Yanyu Zhu, Guanjie Zhang, Gang Guo, Aiping Tong, Liangxue Zhou

    Glioblastoma (GBM) remains one of the most malignant primary tumor in adults with 5-year survival rate less than 10% because of lacking effective treatment. Here we aimed to explore whether B7-H3 could serve as a novel therapeutic target for GBM in chimeric antigen receptor (CAR) T cell therapy. In this study, a CAR targeting B7-H3 was constructed and transduced into T cells by lentivirus. Antitumor effects of B7-H3 specific CAR-T cells were assessed with primary and GBM cell lines both in vitro and in vivo. Our results indicated that B7-H3 was positively stained in most of the clinical glioma samples and its expression levels were correlated to the malignancy grade and poor survival in both low-grade glioma (LGG) and GBM patients. Specific antitumor functions of CAR-T cells were confirmed by cytotoxic and ELISA assay both in primary glioblastoma cells and GBM cell lines. In the orthotropic GBM models, the median survival of the CAR-T cell treated group was significantly longer than that of the control group. In conclusion, B7-H3 is frequently overexpressed in GBM patients and may serve as a therapeutic target in CAR-T therapy.

  • Deletion of apoptosis inhibitor F1L in vaccinia virus increases safety and oncolysis for cancer therapy
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-07-03
    Adrian Pelin, Johann Foloppe, Julia Petryk, Ragunath Singaravelu, Marian Hussein, Florian Gossart, Victoria A. Jennings, Lawton J. Stubbert, Maddie Foster, Christopher Storbeck, Antonio Postigo, Elena Scut, Brian Laight, Michael Way, Philippe Erbs, Fabrice Le Boeuf, John C. Bell

    Vaccinia virus (VACV) possesses a great safety record as a smallpox vaccine and has been intensively used as oncolytic virus against various type of cancer over the past decade. Different strategies were developed to make vaccinia virus safe and selective to cancer cells. Leading clinical candidates, such as Pexa-Vec, are attenuated through deletion of the viral thymidine kinase (TK) gene, which limits virus growth to replicate in cancer tissue. However, tumors are not the only tissues whose metabolic activity can overcome the lack of viral TK. In this study we sought to further increase the tumor specific replication and oncolytic potential of Copenhagen strain VACV ΔTK. We show that deletion of the anti-apoptosis viral gene F1L not only increases the safety of the Copenhagen ΔTK virus, but also improves its oncolytic activity in an aggressive glioblastoma model. The additional loss of F1L does not affect vaccinia virus replication capacity, yet its ability to induce cancer cell death is significantly increased. Our results also indicate that cell death induced by the Copenhagen ΔTK/F1L mutant releases more immunogenic signals, as indicated by increased levels of IL-1B production. A cytotoxicity screen in NCI-60 panel shows that the ΔTK/F1L virus induces faster tumor cell death in different cancer types. Most importantly, we show that compared to the TK-deleted virus, the ΔTK/F1L virus is attenuated in human normal cells and causes fewer pox lesions in murine models. Collectively, our findings describe a new oncolytic vaccinia deletion strain that improves safety and increases tumor cell killing.

  • Recruitment of Intratumoral CD103+ Dendritic Cells by a CXCR4 Antagonist-armed Virotherapy Enhances Antitumor Immunity
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-07-03
    Anna Mistarz, Marcin P. Komorowski, Matthew A. Graczyk, Margaret Gil, Aimin Jiang, Mateusz Opyrchal, Hanna Rokita, Kunle O. Odunsi, Danuta Kozbor

    Intratumoral dendritic cells play an important role in stimulating cytotoxic T cells and driving antitumor immunity. Using a metastatic ovarian tumor model in syngeneic mice, we explored whether therapy with a CXCR4 antagonist-armed oncolytic vaccinia virus activates endogenous CD103+ dendritic cell responses associated with the induction of adaptive immunity against viral and tumor antigens. The overall goal of this study was to determine whether expansion of CD103+ dendritic cells by the virally-delivered CXCR4 antagonist augments overall survival and in situ boosting with a tumor antigen peptide-based vaccine. We found that locoregional delivery of the CXCR4-A-armed virus reduced tumor load and the immunosuppressive network in the tumor microenvironment leading to infiltration of CD103+ dendritic cell that were capable of phagocytic clearance of cellular material from virally-infected cancer cells. Further expansion of tumor-residing CD103+ DCs by injecting the FMS-related tyrosine kinase 3 ligand, the formative cytokine for CD103+ DCs, provided a platform for a booster immunization with the Wilms’ tumor antigen 1 peptide-based vaccine delivered intraperitoneally with polyriboinosinic:polyribocytidylic acid as an adjuvant. The vaccine-induced antitumor responses inhibited tumor growth and increased overall survival indicating that expansion of intratumoral CD103+ dendritic cells by CXCR4-A-armed oncovirotherapy treatment can potentiate in situ cancer vaccine boosting.

  • PD-L1-based cancer vaccine elicits antitumor immunity in a mouse melanoma model
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-06-29
    Zhibing Lin, Yan Zhang, Huaman Cai, Fuqiang Zhou, Hongjun Gao, Li Deng, Rongxiu Li

    Engagement of programmed death 1 receptor (PD-1) and its ligand PD-L1/2 induces a signal transduction pathway that inhibits the activity of tumor infiltrating cytotoxic T lymphocytes, and promotes tumor growth and metastasis. Antibodies blocking PD-1 or PD-L1 can restore antitumor T cell responses and cause long-term remissions in a subset of cancer patients with advanced or refractory tumors. In this study, we ask whether PD-L1 vaccination could confer tumor control in mouse tumor models. To address the central tolerance towards self-molecules, we fused the extracellular domain of PD-L1 (PD-L1E) to the C-terminal of the translocation domain of diphtheria toxin (DTT). DTT is able to elicit CD4+ T cell responses required for inducing robust immune responses against self-molecules. The fusion molecule is named as DPDL1E. When formulated with incomplete Freund's adjuvant (IFA), DPDL1E elicited robust immune responses biased towards Th1 type, and inhibited tumor growth in both preventive and therapeutic mouse tumor models. We further showed that the anti-DPDL1E sera blocked PD-L1 binding to PD-1 in vitro. The DPDL1E vaccination increased the levels of tumor infiltrating T cells (TIL) and reduced the levels of myeloid-derived suppressor cells (MDSCs) as well as exhausted LAG3+PD-1+ CD8+ T cells. All data suggests that DPDL1E vaccination reverts the suppressive phenotype of tumor microenvironment and is a promising strategy for cancer therapy.

  • Tumor cells modified with Newcastle Disease Virus (NDV) expressing IL-24 as a cancer vaccine
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-06-12
    Xiaojing Xu, Cheng Yi, Xiaoqin Yang, Jianwei Xu, Qing Sun, Yonghao Liu, Lixiang Zhao

    IL-24 is promising agent for cancer immunotherapy by inducing apoptosis of tumor cells and enhancing T cells activation and function. In order to improve the antitumor activity induced by Newcastle Disease Virus (NDV)-modified tumor vaccine, we generated a recombinant NDV expressing IL-24 using reverse genetics. Irradiated tumor cells infected with LX/IL-24 showed stable IL-24 expression. The cytotoxicity assay showed that LX/IL-24 infected murine melanoma cells significantly enhanced the antitumor immune response in vitro. Then, the antitumor effects of virus infected tumor cells were examined in the murine tumor models. LX/IL-24 infected tumor cells exhibited strong antitumor effects both in prophylaxis and therapeutic models. LX/IL-24 infected tumor cells increased infiltration of CD4+ T cells and CD8+ T cells in tumor sites, and the antitumor activity of the tumor vaccine modified with LX/IL-24 was dependent on CD8+ T cells. Taken together, our data well illustrated that LX/IL-24 modified tumor cells was a promising agent for cancer immunotherapy.

  • Overexpression of Smac by an armed vesicular stomatitis virus overcomes tumor resistance
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-06-04
    Weike Li, Ravi Chakra Turaga, Xin Li, Malvika Sharma, Zahra Enadi, Sydney Nicole Dunham Tompkins, Kyle Christian Hardy, Falguni Mishra, Jun Tsao, Zhi-ren Liu, Daping Fan, Ming Luo

    Despite reports of successful clinical cases, many tumors appear to resist infection by oncolytic viruses (OVs). To circumvent this problem, an armed vesicular stomatitis virus was constructed by inserting a transgene to express Smac/DIABLO during virus infection (VSV-S). Endogenous Smac in HeLa cells was diminished during wtVSV infection, whereas the Smac level was enhanced during VSV-S infection. Apoptosis was readily induced by VSV-S, but not wtVSV, infection. More importantly, the tumor volume was reduced to a larger extent when xenografts of 4T1 cells in Balb/c mice and OV-resistant T-47D cells in nude mice were intratumorally injected with VSV-S. VSV-S represents a novel mechanism to overcome tumor resistance, resulting in more significant tumor regression due to enhanced apoptosis.

  • Dual regulatory mechanisms of expression and mutation involving metabolism-related genes FDFT1 and UQCR5 during colorectal cancer liver metastasis
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-05-22
    Yu-Shui Ma, Zhi-Jun Wu, Hong-Wei Zhang, Bo Cai, Tao Huang, Hui-Deng Long, Hong Xu, Yong-Zhong Zhao, Yu-Zhen Yin, Shao-Bo Xue, Liu Li, Cheng-Lin Liu, Ru-Ting Xie, Lin-Lin Tian, Ji-Bin Liu, Xu-Ming Wu, Da Fu

    Colorectal cancer (CRC) is the third most common cancer worldwide, and liver metastasis presents a major cause of CRC-associated death. Extensive genomic analysis has provided valuable insight into the pathogenesis and progression of CRC; however, a comprehensive proteogenomic characterization of CRC liver metastasis (CLM) has yet to be reported. Here, we analyzed the proteomes of 44 paired normal colorectal tissues and CRC tissues with or without liver metastasis, as well as analyzed genomics of CRC characterized previously by The Cancer Genome Atlas (TCGA) to conduct integrated proteogenomic analyses. We identified a total of 2170 significantly deregulated proteins associated with CRC liver metastasis, 14.88% of which involved in metabolic pathways. The mutated peptide number was found to have potential prognosis value and somatic variants revealed two metabolism-related genes UQCR5 and FDFT1 frequent mutated only in the liver metastatic cohort and displayed dysregulated protein abundance with biological function and clinical significance in CLM. Proteogenomic characterization and integrative and comparative genomic analysis provides functional context and prognostic value to annotate genomic abnormalities and affords a new paradigm for understand human colon and rectal cancer liver metastasis.

  • The novel oncolytic compound LTX-401 induces antitumor immune responses in experimental hepatocellular carcinoma
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-05-21
    Brynjar Mauseth, Ketil André Camilio, Jihua Shi, Clara Louise Hammarström, Øystein Rekdal, Baldur Sveinbjørnsson, Pål-Dag Line

    LTX-401 is a novel oncolytic compound designed for the local treatment of solid tumors. In the present study we have examined the applicability and efficacy of LTX-401 in a rat model JM1 of hepatocellular carcinoma, with particular interest in its ability to induce antitumor immunity. LTX-401 induces necrotic cell death followed by the release of immunogenic cell death mediators such as high-mobility group box 1 protein, ATP and cytochrome c. When injected into subcutaneous and orthotopic JM1 tumors, LTX-401 treatment resulted in a strong antitumoral effect followed by complete tumor regression in the majority of animals. Additionally, LTX-401 could affect the growth of distal tumor deposits simulating metastases, hence indicating immune-mediated abscopal responses. Furthermore, LTX-401 treatment induced tumor-specific immune responses as seen by protection against tumor rechallenge and increased production of IFN-γ by splenic cells in response to stimulation with tumor cells. Taken together, our data demonstrate that the oncolytic compound LTX-401 provides local tumor control followed by protective immune responses and may be exploited as a novel immunotherapeutic agent in hepatocellular carcinoma.

  • FoxM1 Induced Paclitaxel Resistance via Activation of FoxM1/PHB1/RAF-MEK-ERK Pathway and Enhancement of ABCA2 Transporter
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-05-21
    Chao Huang, Xin Zhang, Li Jiang, Limin Zhang, Ming Xiang, Hongyu Ren

    FoxM1 amplification in human pancreatic cancer predicts poor prognosis and resistance to paclitaxel. Here, a novel role between FoxM1 (FoxM1b and FoxM1c) and Prohibitin1 (PHB1) in paclitaxel resistance has been identified. We adopted a bioinformatics approach to predict the potential effector of FoxM1. It specifically bound to the promoter of PHB1 and enhanced PHB1 expression at transcriptional and post-transcriptional level. FoxM1 contributed to the PHB1/C-RAF interaction and phosphorylation of ERK1/2 kinases, thus promoting paclitaxel resistance. Notably, FoxM1 conferred tumor cell resistance to paclitaxel, but knocking down PHB1 could sensitize pancreatic cancer cells to it. Besides, we identified that ABCA2 promoted paclitaxel resistance under the regulation of FoxM1/PHB1/RAF-MEK-ERK. Thiostrepton, an inhibitor of FoxM1, significantly decreased the expression of PHB1, p-ERK1/2 and ABCA2. It increased the influx of paclitaxel into cell and attenuated FoxM1-mediated paclitaxel resistance in vitro and in vivo. Collectively, our findings defined PHB1 as an important downstream of FoxM1. It was regulated by FoxM1 to maintain phosphorylation of ERK1/2 in drug-resistant cells, and FoxM1 simultaneously enhanced the function of ABCA2, which collectively contributed to paclitaxel resistance. Targeting FoxM1 and its downstream effector PHB1 increased the sensitivity of pancreatic cells to paclitaxel treatment, providing potential therapeutic strategies for patients with paclitaxel resistance.

  • Assessing the completeness of reporting in preclinical oncolytic virus therapy studies
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-05-21
    Dean A. Fergusson, Neil L. Wesch, Garvin J. Leung, Jenna L. MacNeil, Isidora Conic, Justin Presseau, Kelly D. Cobey, Jean-Simon Diallo, Rebecca Auer, Jonathan Kimmelman, Natasha Kekre, Nader El-Sayes, Ramya Krishnan, Brian A. Keller, Carolina Ilkow, Manoj M. Lalu

    Irreproducibility of preclinical findings could be a significant barrier to the ‘bench-to-bedside’ development of oncolytic viruses (OVs). A contributing factor is the incomplete and non-transparent reporting of study methodology and design. Using the National Institutes of Health guidelines for preclinical reporting, a core set of seven recommendations, we evaluated the completeness of reporting of preclinical OV studies. We also developed an evidence map identifying the current trends in OV research. A systematic search of MEDLINE and Embase identified all relevant articles published over an 18 month period. Following screening of 1554 articles, 236 met our a priori defined inclusion criteria. Adenovirus (43%) was the most commonly used viral platform. Frequently investigated cancers included colorectal (14%), skin (12%), and breast (11%). Xenograft implantation (61%) in mice (96%) was the most common animal model. The use of preclinical reporting guidelines was listed in 0.4% of articles. Biological and technical replicates were completely reported in 1% of studies, statistics in 49%, randomization in 1%, blinding in 2%, sample size estimation in 0%, and inclusion/exclusion criteria in 0%. Overall, completeness of reporting in the preclinical OV therapy literature is poor. This may hinder efforts to interpret, replicate, and ultimately translate promising preclinical OV findings.

  • Partial deletion of glycoprotein B5R enhances vaccinia virus neutralization escape while preserving oncolytic function
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-05-21
    Motomu Nakatake, Hajime Kurosaki, Nozomi Kuwano, Kosuke Horita, Mai Ito, Hiromichi Kono, Tomotaka Okamura, Kosei Hasegawa, Yasuhiro Yasutomi, Takafumi Nakamura

    Vaccinia virus (VV) has been utilized in oncolytic virotherapy, but risks a host anti-viral immune response. VV has an extracellular enveloped virus (EEV) form consisting of a normal virion covered with a host-derived outer membrane that enables its spread via circulation while evading host immune mechanisms. However, the immune resistance of EEV is only partial, owing to expression of the surface protein B5R, which has four short consensus repeat (SCR) domains that are targeted by host immune factors. To engineer a more effective virus for oncolytic virotherapy, we developed an enhanced immune-evading oncolytic VV by removing the SCRs from the attenuated strain LC16mO. Although deletion of only the SCRs preserved viral replication, progeny production, and oncolytic activity, deletion of whole B5R led to attenuation of the virus. Importantly, SCR-deleted EEV had higher neutralization resistance than did B5R-wildtype EEV against VV-immunized animal serum; moreover, it retained oncolytic function, thereby prolonging the survival of tumor-bearing mice treated with anti-VV antibody. These results demonstrate that partial SCR deletion increases neutralization escape without affecting the oncolytic potency of VV, making it useful for the treatment of tumors under the anti-virus antibody existence.

  • High Expression of Pseudogene PTTG3P Indicates a Poor Prognosis in Human Breast Cancer
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-03-27
    Weiyang Lou, Bisha Ding, Weimin Fan

    Pseudogenes play pivotal roles in tumorigenesis. Previous studies have suggested that pituitary tumor-transforming 3, pseudogene (PTTG3P), serves as an oncogene in human cancers. However, its expression pattern, biological function, and underlying mechanism in breast cancer remain unknown. In this study, we demonstrated an elevated expression of PTTG3P in breast cancer and discovered that PTTG3P expression correlated negatively with estrogen receptor (ER) and progesterone receptor (PR) status, but linked positively to basal-like status, triple-negative breast cancer status, Nottingham prognostic index (NPI), and Scarff-Bloom-Richardson grade. High expression of PTTG3P was also found to be associated with a poor prognosis of breast cancer. To explore the potential mechanisms of PTTG3P, a PTTG3P-microRNA (miRNA)-mRNA regulatory network was established. Co-expressed genes of PTTG3P were also obtained. Enrichment analysis for these co-expressed genes revealed that they were significantly enriched in mitotic nuclear division and cell cycle. Subsequent research on mechanism of PTTG3P indicated that its expression correlated positively with PTTG1 expression. However, no significant expression correlation between PTTG3P and PTTG2 was observed. Taken together, our findings suggest that increased expression of pseudogene PTTG3P may be used as a promising prognostic biomarker and novel therapeutic target for breast cancer.

  • The Enhanced Tumor Specificity of TG6002, an Armed Oncolytic Vaccinia Virus Deleted in Two Genes Involved in Nucleotide Metabolism
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-03-27
    Johann Foloppe, Juliette Kempf, Nicolas Futin, Jacqueline Kintz, Pascale Cordier, Christelle Pichon, Annie Findeli, Fabien Vorburger, Eric Quemeneur, Philippe Erbs

    Oncolytic vaccinia viruses are currently in clinical development. However, the safety and the tumor selectivity of these oncolytic viruses must be improved. We previously constructed a first-generation oncolytic vaccinia virus by expressing the suicide gene FCU1 inserted in the J2R locus that encodes thymidine kinase. We demonstrated that the combination of this thymidine-kinase-deleted vaccinia virus and the FCU1/5-fluocytosine system is a potent vector for cancer therapy. Here, we developed a second generation of vaccinia virus, named TG6002, expressing FCU1 and with targeted deletions of the J2R gene and the I4L gene, which encodes the large subunit of the ribonucleotide reductase. Compared to the previously used single thymidine-kinase-deleted vaccinia virus, TG6002 is highly attenuated in normal cells, yet it displays tumor-selective replication and tumor cell killing. TG6002 replication is highly dependent on cellular ribonucleotide reductase levels and is less pathogenic than the single-deleted vaccinia virus. Tumor-selective viral replication, prolonged therapeutic levels of 5-fluorouracil in tumors, and significant antitumor effects were observed in multiple human xenograft tumor models after systemic injection of TG6002 and 5-fluorocytosine. TG6002 displays a convincing safety profile and is a promising candidate for treatment of cancer in humans.

  • 更新日期:2019-05-17
  • Single-Chain Variable Fragment-Based Bispecific Antibodies: Hitting Two Targets with One Sophisticated Arrow
    Mol. Ther. Oncolytics (IF 5.710) Pub Date : 2019-03-23
    Raoufeh Ahamadi-Fesharaki, Abolfazl Fateh, Farzam Vaziri, Ghasem Solgi, Seyed Davar Siadat, Fereidoun Mahboudi, Fatemeh Rahimi-Jamnani

    Despite the success of monoclonal antibodies (mAbs) to treat some disorders, the monospecific molecular entity of mAbs as well as the presence of multiple factors and pathways involved in the pathogenesis of disorders, such as various malignancies, infectious diseases, and autoimmune disorders, and resistance to therapy have restricted the therapeutic efficacy of mAbs in clinical use. Bispecific antibodies (bsAbs), by concurrently recognizing two targets, can partly circumvent these problems. Serial killing of tumor cells by bsAb-redirected T cells, simultaneous blocking of two antigens involved in the HIV-1 infection, and concurrent targeting of the activating and inhibitory receptors on B cells to modulate autoimmunity are part of the capabilities of bsAbs. After designing and developing a large number of bsAbs for years, catumaxomab, a full-length bsAb targeting EpCAM and CD3, was approved in 2009 to treat EpCAM-positive carcinomas besides blinatumomab, a bispecific T cell engager antibody targeting CD19 and CD3, which was approved in 2014 to treat relapsed or refractory acute lymphoblastic leukemia. Furthermore, approximately 60 bsAbs are under investigation in clinical trials. The current review aims at portraying different formats of the single-chain variable fragment (scFv)-based bsAbs and shedding light on the scFv-based bsAbs in preclinical development, different phases of clinical trials, and the market.

Contents have been reproduced by permission of the publishers.