Abstract: Objective To investigate whether miR-125b-5p regulates biological behaviors of ovarian cancer cells by targeted regulation of CD147 expression. Methods RT-qPCR was used to detect the expression of miR-125b-5p and CD147 mRNA in ovarian cancer tissues and cancer cell lines. SKOV3 cells transfected with miR-125b-5p mimic and HO8910 cells transfected with miR-125b-5p inhibitor were examined for changes in proliferation, migration and invasion using CCK-8 assay, colony-forming assay and Transwell assay. Starbase was used to predict the potential binding sites between miR-125b-5p and CD147, and double luciferase reporter gene assay was used to verify the targeting relationship. In SKOV3 cells, the effects of co-transfection with miR-125b-5p mimic and pcDNA3.1-CD147 (or pcDNA3.1) plasmid on cell proliferation, migration and invasion were assessed with CCK-8 assay and Transwell assay. Results The expression of miR-125b- 5p was significantly lowered and that of CD147 was increased in both ovarian cancer tissues and ovarian cancer cell lines (P<0.05). Overexpression of miR- 125b-5p in SKOV3 cells resulted in significantly suppressed cell proliferation, migration and invasion, while down-regulation of miR-125b-5p in HO8910 cells promoted cell proliferation, migration and invasion. Bioinformatic analysis predicted that miR-125b-5p binds to CD147, which was confirmed by luciferase reporter gene assay. RT-qPCR and Western blotting showed that miR-125b-5p negatively regulated CD147 expression (P<0.05). In SKOV3 cells, the inhibitory effects of miR-125b-5p mimic on cell proliferation, invasion and migration were significantly attenuated by co-transfection of the cells with pcDNA3.1-CD147 plasmid. Conclusion miR-125b-5p inhibits the migration and invasion of ovarian cancer cells by negatively regulating the expression of CD147.

Key words: ovarian cancer; miR-125b-5p; CD147; migration; invasion