Effects of Cinobufacini Injections on Proliferation and Expression of Topoisomerase of Hepatocarcinoma HepG-2 Cells

Objective: To study the effects of cinobufacini injections on the proliferation and expression of topoisomerase of hepatocarcinoma HepG-2 cells.Method: Experiment were divided into control group and experimental group(cinobufacini injections group 0.105,0.21,0.42 mg.L-1).Cell proliferation was assessed by Methyl Thiazolyl Tetrazolium blue reduction(MTT) assay.Apoptosis was detected by Annexin V / PI staining.Cell cycles were shown through flow cytometry method(FCM).TopoisomeraseⅠ(TopoⅠ),TopoisomeraseⅡ(Topo Ⅱ) mRNA were analyzed by Reverse transcription-polymerase chain reaction(RT-PCR).Expressions of TopoⅠ,Topo Ⅱ protein were analyzed by Western-blot.Result: Cinobufacini injection significantly inhibited HepG-2 cellproliferation(P 0.05),induced apoptosis(P 0.05) in a dose and time dependent manner,induced tumor cells arrested at the S-phase a dose dependent manner.Down regulated mRNA and protein expressions of TopoⅠ,Topo Ⅱ(P 0.05) in a dose dependent manner.Conclusion: Cinobufacini injections can inhibit human hepatocellular carcinoma HepG-2 cells proliferation,induced apoptosis and induced tumor cells arrested at the S-phase.The down regulation of Topo Ⅰ,Topo Ⅱ expressions might be one of the anti-tumor mechanisms of cinobufacini injection.