维生素E琥珀酸酯处理人胃癌细胞过程中自噬与内质网应激的交互作用

Interaction between endoplasmic reticulum stress and autophagy induced by vitamin E succinate in human gastric carcinoma cells

目的:探讨维生素E琥珀酸酯(VES)处理人胃癌SGC-7901细胞过程中自噬与内质网应激的交互作用。方法:用不同剂量(0、5、10、15、20μg/m L)VES处理人胃癌SGC-7901细胞24 h后,激光共聚焦显微镜观察细胞内自噬标志蛋白微管相关蛋白l轻链3(LC3)荧光强度和分布情况,Western blot分别检测内质网应激标志物葡萄糖调节蛋白78(GRP78)、葡萄糖调节蛋白94(GRP94)和LC3、Beclin-1的表达情况;在分别加入自噬抑制剂3-甲基腺嘌呤(3-MA)和氯喹(CQ)以及内质网应激抑制剂4-苯基丁酸(4-PBA)预处理2 h后,以20μg/m L VES处理人胃癌SGC-7901细胞24 h,Western blot分别检测内质网应激标志物GRP78、GRP94及自噬标志蛋白LC3、Beclin-1的变化。结果:与阴性对照组比较,随着VES剂量的增加,激光共聚焦显微镜观察到LC3在细胞内点状分布逐渐聚集和增强,GRP78和GRP94表达先降低后升高(P均<0.05),LC3和Beclin-1表达逐渐升高(P均<0.05);VES+3-MA组及VES+CQ组的GRP78和GRP94蛋白表达均高于单独VES组(P均<0.05);VES+4-PBA组的LC3和Beclin-1蛋白表达均低于单独VES组(P均<0.05)。结论:VES处理人胃癌细胞过程中自噬与内质网应激可以相互调节,具有交互作用。

OBJECTIVE： To discuss the interaction between autophagy and endoplasmic reticulum stress in human gastric cancer SGC-7901 cells treated with vitamin E succinate（VES）. METHODS：Human gastric cancer SGC-7901 cells were treated with VES of different doses（0,5,10,15,20 μg/m L）,then after 24 h laser confocal microscope was used to study fluorescence intensity and distribution of the autophagy marker protein microtubuleassociated protein 1 light chain 3（LC3）.Western blot was used to evaluate the level of endoplasmic reticulum stress markers glucose regulative protein 78（GRP78）,glucose regulative protein 94（GRP94） and LC3,Beclin-1. SGC-7901 cells were pre-treated with autophagy inhibitors,3-methyladenine（3-MA） and chloroquine（CQ）,inhibitor of endoplasmic reticulum stress,4-phenylbutyric acid（4-PBA）,then human gastric cancer SGC-7901 cells were treated with 20 μg/m L VES for 24 h. Western blot evaluated the level of GRP78,GRP94,LC3 and Beclin-1. RESULTS：With increasing doses of VES,the LC3 in cells began to gather and intensity,GRP78 and GRP94 were decreased,then increased again and peaked at 24 h. The levels of GRP78 and GRP94 in VES＋3-MA group and VES＋CQ group were significately higher compared with VES alone（all P〈0.05）. The levels of LC3 and Beclin-1 in VES＋4-PBA group were higher compared with VES alone（both of P〈0.05）. CONCLUSION：In VES-treated human gastric cancer cells,the autophagy and endoplasmic reticulum stress could interact and regulate each other.