Oxymatrine inhibits proliferation and migration of breast cancer cells by inhibiting miRNA-188 and upregulating its target gene, PTEN

Purpose: To explore the potential biological functions of oxymatrine on breast cancer (BCa) cells and the underlying molecular mechanism. Methods: Relative levels of microRNA-188 (miRNA-188) and PTEN (gene of phosphate and tension homology deleted on chromosome ten) in BCa cells, MDA-MB-231 and TB549, were determined. The influence of oxymatrine treatment, miRNA-188 and PTEN on proliferative and migratory abilities in BCa cells were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), cell counting kit-8 (CCK-8) and Transwell assay, respectively. The binding relationship between miRNA-188 and PTEN was evaluated by dual-luciferase reporter gene assay. Results: Oxymatrine downregulated miRNA-188 and upregulated PTEN in BCa cells. Proliferative and migratory activities in BCa were inhibited by treatment of oxymatrine (p < 0.05). Dual-luciferase reporter gene assay results indicated that PTEN was the target gene of miRNA-188. Furthermore, rescue experiments demonstrated that the regulatory loop, oxymatrine/miRNA-188/PTEN, was involved in the regulation of the migration and proliferation of BCa. Conclusion: Oxymatrine treatment inhibits BCa progression by downregulating miRNA-188, leading to the upregulation of PTEN. The results of the current study may provide new insight into the diagnosis and treatment of BCa.