Berberine Sensitizes Human Ovarian Cancer Cells to Cisplatin Through miR-93/PTEN/Akt Signaling Pathway

Background: Berberine, a well-known component of the Chinese herbal medicine Huanglian, has wide range of biochemical and pharmacological effects, including antineoplastic effect, but the exact mechanisms remain unclear. The aim of the present study was to evaluate the potential chemo-sensitization effect of berberine in ovarian cancer cell line A2780. Methods: The expression of miR-93 was measure by RT-PCR. The target of miR-93 was confirmed by luciferase activity assay. Hoechst 33258 staining, Annexin V and PI double staining were used for apoptosis analysis. Results: In this study, we found A2780/DDP cells that were incubated with berberine combined with cisplatin had a significantly lower survival than the control group. Berberine enhanced cisplatin induced apoptosis and induced G0/G1 cell cycle arrest in A2780 cells. Next, we observed that the miR-93 levels in cisplatin resistant cell lines were higher than that in cisplatin sensitive cell lines. Furthermore, our study found berberine could inhibit miR-93 expression and function in ovarian cancer, as shown by an increase of its target PTEN, an important tumor suppressor in ovarian cancer. A2780 cells that were treated with PTEN siRNA had increased survival compared to NC group and this could be partly alleviated by the AKT inhibitor Triciribine. More importantly, A2780 cells that were treated with PTEN siRNA had a survival pattern that is similar to cells with miR-93 overexpression. Conclusion: The results suggested that berberine modulated the sensitivity of cisplatin through miR-93/PTEN/AKT signaling pathway in the ovarian cancer cells.