没食子酸酯诱导膀胱癌细胞的凋亡及对Caspase-3蛋白表达的影响

Epigallocatechin-3-gallate inducing apoptosis of human bladder cancer cell T24 and its impact on the expressions of Caspase-3 protein

目的 观察不同浓度的没食子酸酯（EGCG）对人膀胱癌细胞株（T24）凋亡和Caspase-3蛋白表达的影响.方法 使用不同浓度的EGCG（0、20、40、80 mg/L）处理膀胱癌细胞株T24,通过细胞增殖曲线及克隆形成实验检测EGCG对T24细胞增殖的影响;各种浓度的EGCG处理T24细胞株48 h后,流式细胞仪检测凋亡;逆转录-聚合酶链反应（RT-PCR）法检测Caspase-3基因的表达,Western blot检测蛋白表达量.结果 EGCG可以抑制T24细胞的增殖,不同浓度EGCG刺激后克隆数为200±43、120±32、65±24、35±13（P〈0.05）;可诱导T24细胞凋亡,各组凋亡率为（2.18±0.64）%、（7.17±0.79）%、（34.90±1.36）%、（54.30±0.56）%（P〈0.05）.增殖抑制及凋亡率均随EGCG浓度的增加而增加（P值均〈0.01）;EGCG可以促使T24中的Caspase-3蛋白表达上调,其表达水平随EGCG浓度的增加而增加（P〈0.01）.结论 EGCG可抑制T24细胞增殖并诱导其凋亡,可能通过上调Caspase-3蛋白而发生作用.

Objective To investigate the effects of different concentrations of epigallocatechin-3-gallate （EGCG） on apoptosis of T24 cells and the expressions of Caspase-3 protein.Methods T24 cells were cultured in vitro,and incubated with different concentrations of EGCG （0,20,40,80 mg/L,respectively）.The cell proliferation was measured by growth rate analysis and cloning forming assay.The apoptosis of T24 cells was tested by flow cytometry.The expression of Caspase-3 was detected by using reverse transcription-polymerase chain reaction （RT-PCR） and Western blotting.Results EGCG inhibited the proliferation of T24 cells.After T24 cells were stimulated with different concentrations of EGCG （0,20,40,80 mg/L）,the cloning number of cells was 200 ± 43,120 ± 32,65 ± 24 and 35 ± 13 respectively （ P 〈 0.05 ）.Proliferation inhibition and apoptosis rate was increased with the increased of EGCG concentration.EGCG up-regulated the expression of caspase-3 in T24 cells in a concentration-dependent manner.Conclusion EGCG can inhibit the growth of T24 cells and induce apoptosis probably by up-regulating the expression of caspase-3.