ABSTRACT
Aim To investigate the effect and mecha-nism of quercetin combined with cisplatin on prolifera-tion 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 ra-tios of cells were analyzed by flow cytometry. The gene expression of Bcl-2 and caspase-3 was detected by RT-PCR assay. The protein expression of Bcl-2 and caspase-3 was measured by Western blot assay. Re-sults 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 en-hanced that of caspase-3 at both gene and protein lev-els. Conclusion Synergistic effect of quercetin com-bined with cisplatin on cell proliferation and apoptosis of MG-63 cells is possibly due to reduction of Bcl-2 and enhancement of caspase-3 expression.