Published online Jul 28, 2015. doi: 10.3748/wjg.v21.i28.8562
Peer-review started: December 5, 2014
First decision: January 22, 2015
Revised: February 23, 2015
Accepted: March 30, 2015
Article in press: March 31, 2015
Published online: July 28, 2015
Processing time: 237 Days and 16.4 Hours
Not only is chronic hepatitis C virus (HCV) infection a major public health problem, but also it can cause hepatocellular carcinoma and, more rarely, non-Hodgkin’s lymphoma. These characteristics mean that HCV is the only virus infecting humans that is able to cause two different cancers. The fine pathogenetic and molecular mechanisms by which HCV induces these two malignancies are not completely clear. In the last decade, it has been shown that microRNAs (miRNAs), a class of 21-23-nucleotide molecules modulating post-transcriptional gene expression, make an important contribution to the pathogenesis of several cancers and are also considered highly promising biomarkers. Here, we briefly describe the current knowledge about microRNAs’ involvement in HCV-related molecular oncogenesis. We decided to focus our attention on studies fully conducted on ex vivo samples with this specific etiology, and on cultured cell lines partially or completely expressing the HCV genome. Some of the results reported in this review are controversial, possibly because of methodological issues, differences in sampling size and features, and ethnicity of patients. What is certain is that miRNAs play a remarkable role in regulating gene expression during oncogenetic processes and in viral infection. A clear understanding of their effects is fundamental to elucidating the mechanisms underlying virus-induced malignancies.
Core tip: Not only is chronic hepatitis C virus (HCV) infection a major public health problem, but also it can cause hepatocellular carcinoma (HCC) and, more rarely, non-Hodgkin’s lymphoma. The mechanisms by which the virus induces these malignancies are remain unclear, however, it has become evident recently that small molecules regulating gene expression, the microRNAs, could be involved in these processes. The aim of this review was to establish order in the rich literature concerning microRNAs in HCC and lymphomas, by selecting only the results relating to HCV-induced cancers from the multiple-etiology analyses.