E2F5 was a target gene of miR-181a. (A) Schematic diagram of predicted miR-181a binding site in the E2F5 3′-UTR. (B) Luciferase reporter assays in SMMC-7721 cells, with cotransfection of wt or mut E2F5 3′-UTR and miRNA as indicated. (C) E2F5 mRNA and protein expression levels in SMMC-7721 cells transfected with pTARGET-miR-181a or its respective control. (D) E2F5 mRNA and protein expression levels in SMMC-7721 cells transfected with miR-181a inhibitor or its negative control. β-actin was used as an internal quantitative control. *P < 0.05, **P<0.01.