Salubrinal在ABT737诱导的人肝癌细胞Sk-Hep1凋亡中的作用及机制

Mechanism study of salubrinal on cell apoptosis of human hepatocellular carcinoma cell line Sk-Hep1 induced by ABT737

目的探索ABT737诱导的Sk-Hep1人肝癌细胞凋亡中salubrinal的作用其机制。方法联合应用ABT737与salubrinal后,转染eIF2αS51A质粒(51位丝氨酸不能磷酸化突变体)、eIF2αS51D(51位丝氨酸磷酸化突变体)质粒进入Sk-Hep1人肝癌细胞中,Western Blot检测PARP剪切蛋白、DNA损伤情况、p-eIF2α、eIF2α蛋白表达。结果在Sk-Hep1人肝癌细胞中联合应用salubrinal与ABT737后,与对照组相比,剪切的PARP蛋白表达量明显下调,磷酸化的H2AX蛋白表达量明显下调(P <0.05);p-eIF2α、eIF2α蛋白表达水平没有明显变化。转染eIF2αS51A、eIF2αS51D质粒后,与对照组相比,剪切的PARP、p-eIF2α蛋白表达水平无明显变化(P> 0.05)。结论 Salubrinal对ABT737诱导的细胞凋亡和损伤具有拮抗作用,该拮抗作用可能与eIF2α通路无关。

Objective To investigate the effects and its mechanism of salubrinal on ABT737-induced apoptosis of human hepatocellular carcinoma cell line Sk-Hep1.Methods After the combined application of ABT737 and salubrinal,the plasmids of eIF2αS51A(51 serine non-phosphorylated mutant)and eIF2αS51D(51 serine phosphorylated mutant)were transfected into Sk-Hep1 human hepatocellular carcinoma cells.Then,the cleavaged PARP protein,DNA damage,the p-eIF2αproteins and eIF2αproteins were measured by Western Blot-analyses.Results After the combined application of salubrinal and ABT737 in Sk-Hep1 human hepatocellular carcinoma cells,compared with the control group,the expressions of PARP cleavage proteins and phosphorylated H2AX proteins were both significantly down-regulated(P<0.05).There were no significant changes in the expression levels of p-eIF2αand eIF2αproteins.After transfection of plasmids of eIF2αS51A and eIF2αS51D,there were no significant changes in the expression levels of cleavaged PARP and p-eIF2αprotein compared with the control group(P>0.05).Conclusion Salubrinal has an antagonistic action on apoptosis and DNA injury induced by ABT737,which may be unrelated to the eIF2αpathway.