[Synergistic antitumor effects of tanshinone II A in combination with cisplatin via apoptosis in the prostate cancer cells].

Treatment with the combination of Chinese herbs and cytotoxic chemotherapies showed a higher survival rate in clinical trials. In this report, the results demonstrated that the tanshinone II A, a key component of Salvia miltiorrhiza bunge, when it is combined with the cytotoxic drug cisplatin showed synergistic antitumor effects on human prostate cancer PC3 cells and LNCaP cells in vitro. Antiproliferative effects were detected with MTT assay. Cell cycle distribution and apoptosis were detected by flow cytometer. Protein expression was detected by Western blotting. The intracellular concentration of cisplatin was detected by high performance liquid chromatography. The results demonstrated that tanshinone II A significantly enhanced the antiproliferative effects of cisplatin on human prostate cancer PC3 cells and LNCaP cells with the increase of the intracellular concentration of cisplatin. These effects were correlated with cell cycle arrested at S phase and cell apoptosis. The apoptosis might be achieved through death receptor pathway and mitochondrial pathway. Furthermore, the Bcl-2 family members were also involved in this apoptotic process. Collectively, these results indicated that the combination of tanshinone II A and cisplatin had a better treatment effect in vitro not only on androgen-dependent LNCaP cells but also on androgen-independent PC3 cells.