Fig. 4

MiR-216b directly targets the 3′-UTR of FOXM1 mRNA. a Schematic representation of the mature miR-216b sequence, putative miR-216b target site in the 3′-UTR of FOXM1 mRNA, and a mutant of miR-216b containing three altered nucleotides in the FOXM1 binding site (miR-216b-mut). b Luciferase assay of PsiCHECK2-FOXM1–3’UTR reporter cotransfected with miR-216b mimics, miR-216b inhibitors or miR-216b mutant in HeLa cells. MiR-216b mimics significantly repressed the luciferase activity of the PsiCHECK2-FOXM1 3′-UTR-luciferase reporter, whereas miR-216b inhibitors showed the opposite effect. MiR-216b mutant had no obvious effect on the luciferase activity of FOXM1 3′-UTR reporter. NC was HeLa cells transfected with mimic control. NC-in was HeLa cells transfected with negative control inhibitors. * P < 0.05 compared with NC. c Western blotting analysis showed the relative expression levels of FOXM1 protein in HeLa cells transfected with miR-216b mimics or miR-216b inhibitors, compared with corresponding control cells (NC and NC-in), 48 h after transfection. MiR-216b mimics suppressed FOXM1 expression and miR-216b inhibitors increased FOXM1 protein level. β-actin served as an internal control. * P < 0.05