告达庭增强 TRAIL 诱导的 HepG2细胞凋亡

摘要

目的：研究C21甾体苷元告达庭对肿瘤坏死因子凋亡诱导配体（ TRAIL）诱导的HepG2肝癌细胞增殖和凋亡的影响，并进一步明确其作用机制。方法：采用MTT法和细胞集落形成实验检测告达庭与TRAIL联合对细胞增殖的影响；TUNEL染色法检测细胞凋亡的变化；免疫印迹实验分析蛋白的表达水平。结果：告达庭与TRAIL联合作用HepG2细胞24 h后，细胞活力明显下降，细胞增殖受到抑制；同时，两者联用后细胞凋亡数目明显增加，显著高于告达庭和TRAIL单用诱导的细胞凋亡率；与对照相比，告达庭与TRAIL联用促进了caspase－3、caspase－7、caspase－9和PARP的活性切割，而凋亡抑制蛋白survivin的表达则下调。结论：告达庭能够增强TRAIL诱导HepG2细胞凋亡，其机制可能与激活caspase家族因子的活性切割和抑制survivin的表达相关。%AIM:To determine whether caudatin , a C21 steroidal aglycone , enhances tumor necrosis factor-re-lated apoptosis-inducing ligand ( TRAIL)-associated HepG2 cell apoptosis .METHODS:Cell growth inhibition was deter-mined by MTT assay and cell colony formation assay .The TUNEL apoptosis detection kit was used to analyze cell apopto-sis, and the protein expression was examined by Western blotting .RESULTS:Combination of caudatin with TRAIL signi-ficantly reduced cell proliferation and increased the apoptotic rate of HepG 2 cells compared with the use of each agent alone.This was evidenced by marked increases in caspase-3, caspase-7, caspase-9 and PARP cleavages in the cells treated with caudatin and TRAIL-compared with control group .Combination of caudatin with TRAIL also led to the strong suppres-sion of survivin .CONCLUSION:Caudatin synergizes HepG 2 cells to TRAIL-induced apoptosis by promoting the cleava-ges of caspase-3, caspase-7, caspase-9 and PARP and inhibiting the expression of survivin .