Figure 5

miR-31 suppresses FIH1 and MCM2 expression in NPC cells. (a) Protein expression of FIH1 and MCM2 proteins were reduced in the C666-1 cells transfected with miR-31 when compared with controls (Right panel). By qRT-PCR, no significant changes of FIH1 and MCM2 transcripts were found in the miR-31-transfected C666-1 cells (Left panel). (b) Luciferase reporter assay showing the effects of miR-31 on 3’ untranslated region (3’UTR) of FIH1 and MCM2 mRNA. Luciferase activity was normalized by the renilla luciferase control. The binding of miR-31 on 3’UTR of FIH1 and MCM2 significantly decreased the luciferase activity. As a control, reporter vector carrying miR-31 complementary sequence in the 3’ UTR were also constructed (miR-31) which upon binding showed a near complete abolishment of miR-31 luciferase activity. Three independent experiments with mean ± SEM. Student-t test was used for statistical significance, with a p-value of less than 0.05 was considered significant (**p < 0.01, ***p < 0.001).