Abstract

The transcriptional activity of genes encoding cancer/testis antigens (CTA) and its regulation in colorectal cancer (CRC) is not well understood. The expression of CTA coding genes (CT genes) and possible mechanisms for its regulation, including expression and copy number of DNA methyltransferase genes, copy number of CT genes, microRNA expression, and LINE-1 methylation in CRC were analyzed in this study. The relative expression levels and copy number variation of 19 genes, MAGE-A1, -A2, -A3, -A4, -B1, -B2, GAGE-1, -3, -4, MAGEC1, BAGE, XAGE3, NY-ESO1, SSX2, SCP1, PRAME1, DNMT1, DNMT3A, and DNMT3B, were determined using real-time quantitative PCR. Quantitative methylation of LINE-1 CpG sites was evaluated by pyrosequencing, and multiple parallel sequencing was used to determine the level of microRNA expression. It was found that in colon tumor tissue a multidirectional destabilization of the transcriptional activity of DNMT3A and DNMT3B, associated with copy number variation and a change in expression of the CT genes BAGE, SSX2 and PRAME1, is observed. A strong positive correlation was found between copy number and expression of the BAGE, SSX2, and PRAME1 genes. As a result of multiple parallel sequencing, 6 differentially expressed microRNAs (hsa-miR-143-3p, hsa-miR-26a-5p, hsa-miR-25-3p, hsa-miR-92a-3p, hsa-miR-21-5p, and hsa-let-7i-5p), targeting the CT genes GAGE1, SSX2, PRAME, SCP1, and the gene for DNA methyltransferase 3A (DNMT3A), were found. Data on the mechanisms of the transcriptional activity regulation of CT genes in malignant colon tumors are important for the development of CTA-dependent immunotherapeutic approaches for the treatment of this type of tumor.

中文翻译：

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大肠癌患者癌症/睾丸抗原基因表达的调控

摘要

编码癌症/睾丸抗原（CTA）的基因的转录活性及其在结直肠癌（CRC）中的调控尚不清楚。本研究分析了CTA编码基因（CT基因）的表达及其调控机制，包括CRC中DNA甲基转移酶基因的表达和拷贝数，CT基因的拷贝数，microRNA表达和LINE-1甲基化。相对表达水平和复制的基因19数变异，MAGE-A1，-A2，-A3，-A4，-B1，-B2，GAGE-1 ，-3，-4，MAGEC1，BAGE，使用实时定量PCR确定XAGE3，NY-ESO1，SSX2，SCP1，PRAME1，DNMT1，DNMT3A和DNMT3B。通过焦磷酸测序评估LINE-1 CpG位点的定量甲基化，并使用多重平行测序来确定microRNA表达的水平。发现在结肠肿瘤组织中，DNMT3A和DNMT3B转录活性的多向失稳，与拷贝数变异和CT基因BAGE，SSX2和PRAME1表达的变化有关。观察到。发现BAGE，SSX2和PRAME1基因的拷贝数与表达之间存在强正相关。多重平行测序的结果是6个差异表达的microRNA（hsa-miR-143-3p，hsa-miR-26a-5p，hsa-miR-25-3p，hsa-miR-92a-3p，hsa-miR-21 -5p和hsa-let-7i-5p），针对CT基因GAGE1，SSX2，PRAME，SCP1和DNA甲基转移酶3A（DNMT3A）基因）， 被发现。恶性结肠肿瘤中CT基因转录活性调控机制的数据对于开发依赖于CTA的免疫疗法来治疗这种类型的肿瘤非常重要。