The X protein of hepatitis B virus activates hepatoma cell proliferation through repressing melanoma inhibitory activity 2 gene

► We demonstrated that HBV represses MIA2 gene expression both invitro and in vivo. ► The X protein of HBV plays a major role in such regulation. ► Knock-down of MIA2 in HepG2 cells activates cell growth and proliferation. ► HBx activates cell proliferation, over-expression of MIA2 impaired such regulation. ► HBx activates hepatoma cell proliferation through repressing MIA2 expression.