乙型肝炎病毒X蛋白通过靶向miR-200c诱导DNA异常甲基化

乙型肝炎病毒x (hepatitis B virus x,HBx)蛋白是导致肝癌(hepatocellular Carcinoma,HCC)的重要因素.但HBX在HCC形成过程中表观遗传机制尚有待阐明.本研究发现microRNA-200c (miR-200c)在过表达乙型肝炎病毒的HCC中下调,并且其直接靶向DNA甲基转移酶3A (DNA methyltransferase 3A,DNMT3A).此外,miR-200c和DNMT3A在HB诱发的肝癌组织中呈现负相关.乙型肝炎病毒诱导miR-200c下调,进而引起DNMT3A表达上调,导致细胞中肿瘤相关基因的启动子超甲基化.我们对乙型肝炎病毒诱导的肝癌表观遗传学改变进行了进一步研究,并提出一种基于miRNA的靶向治疗乙型肝炎病毒相关肝癌的潜在方法.

Hepatitis B virus x protein induces aberrant DNA methylation by targeting miR-200c

The hepatitis B virus x (HBx) protein has been implicated in the pathogenesis of HBV-associated hepatocellular carcinoma (HCC). The mechanisms of HBx involved in epigenetic changes during hepatocarcinogenesis are still obscure. We report here that microRNA-200c (miR-200c) was downregulated in HBV-expressing HCC cells and it targeted DNMT3A directly.. In addition, an inverse correlation between miR-200c and DNA methyltransferase 3A (DNMT3A) was founded in HBV-induced HCC tissues. HBV-induced downregulation of miR-200c upregulated DNMT3A expression, and then resulted in promoter hypermethylation of tumor-related genes in HCC. Our data supplied an epigenetic insight into HBV-induced HCC and identified a potential miRNA-based targeted approach for treating HBV-related HCC.