Liver-specific microRNA miR-122 enhances the replication of hepatitis C virus in nonhepatic cells

The liver-specific microRNA miR-122 has been shown to be required for the replication of hepatitis C virus (HCV) in the hepatoma cell line Huh7. The aim of this study was to test if HCV replication can be modulated by exogenously expressed miR-122 in human embryonic kidney epithelial cells (HEK-293). Our results demonstrate that miR-122 enhances the colony formation efficiency of the HCV replicon and increases the steady-state level of HCV RNA in HEK-293 cells. Therefore, we conclude that although miR-122 is not absolutely required, it greatly enhances HCV replication in nonhepatic cells.