【摘要】 目的:探讨人剪接型X盒结合蛋白1(X-box binding protein1spliced,XBP1S)对肝癌HepG2细胞增殖和凋亡的影响。方法:应用衣霉素(tunicamycin,Tm)和毒胡萝卜素(thapsigargin,Tg)建立HepG2细胞的内质网应激(endoplasmic reticulum stress,ERS)模型。将XBP1S真核表达载体pcDNA3.1(-)-XBP1S和靶向XBP1S的RNA干扰质粒pSUPER-XBP1S转染HepG2细胞,MTT法检测细胞的增殖能力,荧光显微镜下观察细胞的形态学变化,FCM法检测细胞凋亡率,Western印迹法检测caspase12的表达。结果:转染pSUPER-XBP1S可有效抑制细胞增殖,而转染pcDNA3.1(-)-XBP1S可促进细胞增殖。荧光显微镜下可见Tm处理组细胞出现细胞凋亡的形态学改变,进一步下调XBP1S的表达可使这一改变增强。对照组、Tm组、Tm+pSUPER-XBP1S转染组和Tm+pcDNA3.1(-)-XBP1S转染组细胞的凋亡率分别为5.21%、41.51%、52.15%和35.87%,差异有统计学意义(P<0.05)。HepG2细胞中caspase12的表达,Tm组高于对照组,Tm+pSUPER-XBP1S转染组高于Tm组,Tm+pcDNA3.1(-)-XBP1S转染组低于Tm组。结论:XBP1S可以促进肝癌HepG2细胞增殖,抑制或促进XBP1S表达可调节ERS介导的细胞凋亡。更多还原

【Abstract】 Objective: To study the effects of X-box binding protein 1 spliced(XBP1S) on cell proliferation and apoptosis of hepatoma HepG2 cells.Methods: The endoplasmic reticulum stress(ERS) model of HepG2 cells was constructed and induced by tunicamycin(Tm)and thapsigargin(Tg).XBP1S eukaryotic expression vector pcDNA3.1(-)-XBP1S and target XBP1S RNA interference plasmid pSUPER-XBP1S were transfected into HepG2 cells.Cell proliferation was measured by MTT assay.The morphology changes of cells were observed under a fluorescence microscope.The apoptosis was detected by flow cytometry.The expression of caspase12 protein was determined by Western blotting.Results: The proliferation of HepG2 cells was inhibited after transfection with pSUPER-XBP1S,but that was improved after transfection with pcDNA3.1(-)-XBP1S.The apoptotic morphologic changes were obvious in Tm-treated group,and this effect was enhanced by down-regulation of XBP1S expression.The apoptotic rates of cells in the control,Tm-treated,Tm plus pSUPER-XBP1S-transfected and Tm plus pcDNA3.1(-)-XBP1S-transfected groups were 5.21%,41.51%,52.15% and 35.87%,respectively(P<0.05).The expression levels of caspase12 were gradually increased in the control,Tm plus pcDNA3.1(-)-XBP1S-transfected,Tm-treated and Tm plus pSUPER-XBP1S-transfected groups.Conclusion: XBP1S can improve the proliferation of HepG2 cells.Upor down-regulation of XBP1S expression level maybe regulate ERS-mediated apoptosis of HepG2 cells.更多还原