HBV down-regulated the expression of E2F5. (A) Relative E2F5 mRNA and protein levels in Ad-GFP or Ad-HBV infected HepG2 cells. (B) Effect of HBV on cell proliferation was measured by MTS assay in HepG2 cells infected with Ad-HBV. (C) HepG2.2.15 cells were transfected with NC or miR-181a inhibitor, and then MTS assay was performed. (D) Representative pictures of colony formation assay of miR-181a inhibitor transfected HepG2.2.15 cells. Colonies were evaluated and values were reported as the ratio between miR-181a inhibitor transfected cells and NC transfected cells. **P<0.01.