The Effect of miR-503-5p on the Proliferation, Invasion, Migration and Epithelial Interstitium of Cervical Cancer HeLa Cells via Targeting E2F3

  Objective  To investigate the effect of miR-503-5p on the proliferation, invasion, migration and epithelialization of cervical cancer HeLa cells via targeting E2F3.

  Methods  Four ccervical cancer HeLa cells groups were set up including control group, mimic-NC group, miR-503-5p mimic group, E2F3 group, miR-503-5p mimic+E2F3 group (mimic+E2F3 group). The plasmids were separately or jointly transinfected into cervical cancer Hela cells of each group by Lipofectamine 2000, After transinfection, the target gene was predicted by gene prediction software, the targeting relationship was verified by fluorescein experiment, the expression of miR-503-5p and E2F3 was detected by RT-PCR, cell proliferation was detected by MTT assay, expression of Ki67, proliferating cell nuclear antigen (PCNA), E-cadherin and N-cadherin were detected by Western blot, cell invasion was detected by Transwell, and cell migration was detected by scratch test. Nude mice were divided into control group and miR-503-5p mimic group, and 0.2 mL of cervical cancer HeLa cell suspension transfected with mimic-NC or miR-503-5p mimic was injected subcutaneously into the ventral side of the right hind limb of nude mice. Thirty days post injection, the nude mice were sacrificed by cervical dislocation. The tumor weight was weighed by an electronic balance, and the expression of KI67 and Vimentin in the tumor tissue was detected by immunohistochemistry.

  Results  The expression level of miR-503-5p in cervical cancer HeLa cells was down-regulated, miR-503-5p directly targeted E2F3 by binding with E2F3 at binding sites in the 3'UTR region. Over-expressing of miR-503-5p inhibited the expression of E2F3, significantly decreased cell growth rate and the expression level of Ki67 and PCNA, decreased the number of invasive cells, widened the scratches, reduced the healing rate, up-regulated the expression of E-cadherin and also down-regulated the expression of N-cadherin (P<0.01). Over-expressing of miR-503-5p significantly reduced the volume and weight of transplanted tumors, and decreased the proportion of positive Ki67 and Vimentin (P<0.01).

  Conclusion  miR-503-5p inhibits the proliferation, invasion, migration and epithelialization of cervical cancer HeLa cells by targeting E2F3.