Hepatitis C virus infection, microRNA and liver disease progression

Table 1 Altered expression of microRNAs in association with Hepatitis C virus infection and liver disease progression

miRNA	Expression1	Target genes	Function
MiRNAs that facilitates HCV infection
miR-122	Up	5’ UTR in HCV genome	Promote HCV replication[16-18] and IRES mediated HCV translation[21]
		Xrn1	Inhibit 5’decay of HCV RNA[22]
		Cyclin G1	Promote Alcohol induced viral replication[27]
		SOCS3	Enhance methylation at SOCS3 gene promoter, inhibits IFN-induced ISRE activity[41]
miR-130a	Up	IFITM1	Inhibits type 1 IFN signaling pathway and promotes HCV replication[33]
miR-141	Up	DLC-1	Promote viral replication[40]
miR-21	Up	MyD88 and IRAK1	Negatively regulate IFN signaling[42]
MiRNAs that suppresses HCV infection
miR-448	Unknown	Core region in HCV genome	Inhibits viral replication[28]
miR-196/196a	Unknown	NS5A region in HCV genome	Inhibits viral replication[28]
		Bach1	Inhibits HCV RNA and NS5A protein expression, relieve oxidative stress by upregulating HMOX1 gene expression[31]
let-7b	Unknown	NS5B and 5’UTR regions in HCV genome	Reduces HCV infectivity[29]
miR-199a	Unknown	5’ UTR in HCV genome	Inhibits viral replication[30]
miR-27a	Up	RXRα and ABCA1	Regulates lipid metabolism, decrease viral infectivity[38]
MiRNAs that promote inflammation and fibrosis upon HCV infection
miR-449a	Down	NOTCH1	Regulates YKL40 promoter activity and promotes inflammation[47]
miR-21	Up	SMAD7	Increase TGF-β signaling and promote fibrosis[50]
miR-29	Down	COL1A1, COL3A1	Potentiate fibrosis by activating hepatic stellate cells[32]
miR-155	Up	APC	Promote cell proliferation by activating Wnt/β-Catenin signaling pathway[48]

¹Denotes endogenous expression in Hepatitis C virus (HCV) infected liver biopsy patients or HCV infected hepatocytes. UTR: Untranslated region; IFN: Interferon; TGF: Transforming growth factor; miR/miRNA: MicroRNA.