Effect of quercetin combined with cisplatin on proliferation and apoptosis of human osteosarcoma cell line MG-63

Aim To investigate the effect and mechanism of quercetin combined with cisplatin on proliferation and apoptosis of human osteosarcoma cell line MG-63. Methods MG-63 cells were treated with quercetin alone or combined with cisplatin. Cellular morphologic changes were observed under inverted phase contrast microscope. The effects of proliferation inhibition were assayed by CCK-8 method. The combination effect was judged through Chou-Talaly analysis. The apoptosis ratios of cells were analyzed by flow cytometry. The gene expression of Bcl-2 and caspase-3 was detected by RTPCR assay. The protein expression of Bcl-2 and caspase-3 was measured by Western blot assay. Results Quercetin alone or combined with cisplatin could inhibit the proliferation,but induce the apoptosis of MG-63 cells. Combination of quercetin and cisplatin revealed a synergistic effect on cell proliferation and apoptosis as it reduced the expression of Bcl-2 but enhanced that of caspase-3 at both gene and protein levels. Conclusion Synergistic effect of quercetin combined with cisplatin on cell proliferation and apoptosis of MG-63 cells is possibly due to reduction of Bcl-2and enhancement of caspase-3 expression.