Studies On Apoptosis Of Human Hepatoma Cells SMMC-7721Induced By Periplaneta Americana Extract

ObjectiveTo explore the effect of periplaneta americana extract on the proliferationand apoptosis of SMMC-7721and its possible mechanism. It will supplyexperimental basis for the futher invesitigation of anti-tumor mechanism ofperiplaneta americana extract and will provide the theoretical basis for clinicaltreatment of liver cancer.MethodsThe proliferation of human hepatoma cells SMMC-7721were assayed byMTT. The apoptosis was analyzed by flow cytometry. The mitochondrialmembrane potential was detected by JC^-1 staning method. The activity ofCaspase-3and Caspase-9were detected by spectrophotometry. The proteinexpressions of Bax, Bcl-2were tested by western blotting test.ResultsMTT assay showed that periplaneta americana extract(12.5μg·mL^-1,25μg·mL^-1,50μg·mL^-1,100μg·mL^-1,200μg·mL^-1) inhibited human hepatomacells SMMC-7721proliferation in time-and dose-dependent manner （P<0.05）.The inhibiting concentration of50%cell growth （IC50） at24h,48hand72hwere148.9μg·mL^-1,85.6μg·mL^-1,37.2μg·mL^-1, respectively. Apoptotic rates ofthree different concentration groups of periplaneta americana extract (50 μg·mL^-1,100μg·mL^-1,200μg·mL^-1)were（12.34±0.98）%（,18.67±1.23）%and（26.38±1.14）%（P<0.01）. Mitochondrial membrane potential in the processof apoptosis was falling, Caspase-3and Caspase-9activity increased（P<0.05）.Western blot method showed that the protein expressions of Baxincreased, Bcl-2decreased,the ratio of Bax/Bcl-2increased.ConclusionsPeriplaneta americana extract inhibited proliferation of human hepatomacells SMMC-7721and induced its apoptosis,by up-regulation of the levels ofBcl-2and down-regulation of the levels of Bax. Aesculetin starts thedownstream effect of Caspase. Periplaneta americana extract can induce theapoptosis of human hepatoma cells SMMC-7721through mitochondrialpathway.