MicroRNAs (miRNAs) are important gene regulators that participate in tumorigenesis. Previous studies have implicated that miR-214 is a tumor suppressor that is capable of inhibiting human hepatocellular carcinoma (HCC) cell growth. However, the mechanism by which miR-214 suppresses tumor development remains unknown. In the present study, miR-214 was observed to suppress tumor proliferation by directly targeting E2F transcription factor 3 (E2F3) in HCC cells. Colony formation, cell cycle and proliferation assays were employed to study the tumor suppressor role of miR-214 in cell proliferation. In addition, western blotting and dual-luciferase reporter assays were used to evaluate whether E2F3 was a target of miR-214. The results of these analyses revealed that E2F3 was a novel target of miR-214. Furthermore, enhanced expression of miR-214 or silencing of E2F3 inhibited the proliferation of HCC SMMC-7721 cells. These findings suggest that miR-214 suppresses HCC growth by targeting E2F3, and may provide a novel approach for the treatment of human HCC.
Keywords: E2F3; hepatocellular carcinoma; miR-214; proliferation.