【摘要】 目的:研究稳定干扰NOR1基因对宫颈癌HeLa细胞系的影响。方法:采用pSUPER.neo+GFP载体构建靶向NOR1基因的shRNA干扰载体pSUPER-shNOR1-1,pSUPER-shNOR1-2以及无关序列对照载体pSUPER-scramble,通过脂质体转染HeLa细胞,经G418筛选获得稳定干扰细胞系。采用RT-PCR和Western印迹检测NOR1 mRNA和蛋白表达水平。采用MTT法测定细胞生长曲线。采用H2O2处理HeLa细胞,采用Hoechst 33258染色和TUNEL法测定细胞凋亡。Western印迹检测干扰NOR1对HeLa细胞凋亡相关分子Bcl-2,caspase和聚ADP核糖聚合酶(poly ADP-ribose polymerase,PARP)表达的影响。结果:稳定感染的shRNA干扰载体pSUPER-shNOR1-1和pSUPER-shNOR1-2抑制了HeLa细胞内源性NOR1的基因表达,成功构建了稳定干扰NOR1基因的HeLa细胞系。MTT生长曲线测定表明:与pSUPER-scramble质粒转染细胞相比,稳定转染pSUPER-shNOR1-1和pSUPER-shNOR1-2质粒促进了HeLa细胞的活力和增殖,并抑制了H2O2诱导的HeLa细胞凋亡。Western印迹检测发现稳定干扰NOR1抑制了H2O2诱导的HeLa细胞caspase 9和PARP的活化,上调了Bcl-2蛋白的表达。结论:稳定干扰NOR1基因促进了HeLa细胞的活力与生长,并抑制了H2O2诱导的细胞凋亡,其机制与干扰NOR1表达引起抗凋亡分子Bcl-2表达增加和抑制caspase 9活化有关。更多还原

【Abstract】 Objective: To explore the effect of the oxidored nitro domain containing protein 1(NOR1) gene knockdown on the biological behavior of HeLa cells in cervical carcinoma.Methods: The recombinant plasmids pSUPER-shNOR1-1, pSUPER-shNOR1-2 and pSUPERscramble, which targeted to NOR1 gene, were constructed by pSUPER.neo+GFP vector, transfected into HeLa cells respectively using Lipofectamine 2000 reagent, and followed by G418 selection. The expression level of NOR1 mRNA and protein were determined by RT-PCR and Western blotting, respectively. Methyl thiazolyl tetrazolium(MTT) assay was performed to determine the growth curve of cell viability. The stable transfectants were treated with H2O2 and cell apoptosis was determined by Hoechst 33258 staining and terminal deoxynucleotidyl transferasemediated dUTP nick end labeling(TUNEL) assay. The expression levels of Bcl-2, cleaved caspase 9 and poly ADP-ribose polymerase(PARP) were measured by Western blot.Results: NOR1-knockdown HeLa cells were successfully constructed by transfection of pSUPER-shNOR1-1 or pSUPER-shNOR1-2 plasmids into HeLa cells. MTT assay showed that the silence of endogenous NOR1 in HeLa cells could lead to the increase in cell viability and proliferation, and the inhibition of H2O2-induced apoptosis compared with the negative control. Western blot showed that the expression level of active caspase 9 and cleaved PARP was inhibited in NOR1-knockdown cells when they were treated with H2O2 while the expression level of Bcl-2 protein increased.Conclusion: Silence of endogenous NOR1 facilitates the cell viability and growth of HeLa cells, and attenuates HeLa cells apoptosis induced by H2O2, which might be mediated by up-regulation of Bcl-2 level and down-regulation of the cleaved caspase 9 cascade.更多还原