MicroRNA‐let‐7c suppresses hepatitis C virus replication by targeting Bach1 for induction of haem oxygenase‐1 expression

Summary Micro RNA s are small noncoding RNA s that are central factors between hepatitis C virus ( HCV ) and host cellular factors for viral replication and liver disease progression, including liver fibrosis, cirrhosis and hepatocellular carcinoma. In the present study, we found that overexpressing miR‐let‐7c markedly reduced HCV replication because it induced haem oxygenase‐1 ( HO ‐1) expression by targeting HO ‐1 transcriptional repressor Bach1, ultimately leading to stimulating an antiviral interferon response and blockade of HCV viral protease activity. In contrast, the antiviral actions of miR‐let‐7c were attenuated by miR‐let‐7c inhibitor treatment, exogenously expressing Bach1 or suppressing HO ‐1 activity and expression. A proposed model indicates a key role for miR‐let‐7c targeting Bach1 to transactivate HO ‐1–mediated antiviral actions against HCV . miR‐let‐7c may serve as an attractive target for antiviral development.