Liver micro-RNAs and their role in different HCV genotype infections

Hepatitis C virus (HCV) is a common cause of liver cirrhosis and hepatocellular carcinoma (HCC) worldwide. The combination of ribavirin and peg-interferon, as standard treatment for HCV infection, seems very promising. Many studies have revealed that despite following standard HCV treatment, a high proportion of HCV genotypes 1 and 4 poorly attain (42% to 46%) the SVR condition, whereas it is somehow easier for HCV genotypes 2 and 3 (76%-82%). Overall, genotypes 1 and 4 antiviral therapies must be continued up to one year to achieve SVR, whereas in individuals infected with genotypes 2 and 3 must continue therapy for six months. Since 2011, direct-acting antiviral agents (DAA) have been introduced that target the HCV-encoded proteins which are vital for replication of the virus. The first generation of DAA, telaprevir, in combination with peg-interferon and ribavirin, more efficiently inhibits replication of genotype 1. Although the level of DAA SVR rate is high, the new treatment has some undesirable adverse effects. Micro-RNAs (miRNAs), as the new HCV drug approach, open a new insight into the treatment of non-responder HCV patients. Altered expression of miRNAs is involved in the aspects of HCV infection and HCC. In the current review, we attempt to better understand the HCV life cycle, liver miRNAs, and their role in this viral infection.