Genistein调节肝癌HepG2细胞Caspase3蛋白表达诱导凋亡的作用研究

Effects of Genistein on the Expression of Caspase3 and the Induction of Apoptosis in Hepatocellular Carcinoma HepG2 Cells

目的探讨三磷酸肌醇(IP3)和Caspase3蛋白表达变化在genistein诱导肝癌细胞凋亡中的作用。方法以肝癌HepG2细胞培养72h为对照组,实验各组以60μmol/L的genistein作用于HepG2细胞不同时间后,应用同位素试剂盒检测细胞IP3含量,Westernblotting分析细胞Caspase3蛋白表达,流式细胞仪检测细胞凋亡率。结果Genistein作用于肝癌HepG2细胞12、24、48、72h,各时相IP3含量显著低于对照组[(12.0±1.4)pmol/106cells、(7.5±0.8)pmol/106cells、(5.6±0.5)pmol/106 cells、(4.3±0.6)pmol/106 cellsvs(29.2±0.6)pmol/106 cells,P<0.01];24h后Caspase3蛋白的RI显著高于对照组(2.7±0.2,7.4±0.5,7.4±0.5,30.7±1.6vs0.24±0.06,P<0.05);24h后各时相细胞凋亡率为显著高于对照组[(2.7±0.2)%、(7.4±0.5)%、(20.5±2.0)%、(30.7±1.6)%vs(2.6±0.1)%,P<0.01]。结论Genistein能减少IP3生成,上调Caspase3蛋白表达,诱导肝癌细胞凋亡。

Objective To examine the expression of 1, 4, 5-trisphosphate inositol （IP3） and Caspase3 in genistein-induced apoptotic HepG2 cells. Method HepG2 cells were treated with 60 μmol/L genlstein for 12 h, 24 h, 48 h and 72 h. The production of IP3, Caspase3 and apoptotic cells were determined by IP3-[^3H] Birtrak assay, Western blotting and flow cytometry, respectively. Result After the treatment with genistein, the levels of IP3 in cells at 12 h （12.0±1.4）pmol/10^6 cells, 24 h （7.5±0.8）pmol/10^6 cells, 48 h （5.6±0.5）pmol/10^6 cells and 72 h （3.3±0.6）pmol/10^6 cells were significantly lower than the untreated control cells （29.2±0.6）pmol/10^6 cells. The levels of Caspase3 expressed as a signal ratio between Caspase3 and （-actin） in gensitein-treated cells （12 h, 2.7± 0.2; 24 h, 7.4±0.5; 48 h, 7.4±0.5; and 72 h, 30.7±1.6） were higher than the untreated cells （0.24±0.06）. The percentage of apoptotic cells at 24 h （7.4±0.5）%, 48 h （20.5±2.0）% and 72 h （30.7±1.6）% was also significantly higher than the control cells （2.6±0.1）%, P 〈 0.01. Conclusion Genistein induces apoptosis in HepG2 cells by reducing the production of IP3 and the increase in Caspase3 expression.