GRP78在胃癌中表达水平及沉默表达后对人胃癌SGC-7901/DDP细胞增殖和凋亡的影响

摘要

Objective To study the expression of molecular chaperone glucose regulated protein 78 ( GRP78 ) in dif-ferent gastric tissues (normal and gastric cancer tissues) and cells (normal gastric epithelial cells GES1, gastric cancer cells SGC-7901 and multi-drug resistance gastric cancer cells SGC-7901/DDP); to reveal the effect of GRP78 silence expression on proliferation and apoptosis of SGC-7901/DDP cells. Methods Real-time fluorescence quantitative PCR ( Real-time PCR) and Western blotting methods were used to detect the expressions of GRP78 mRNA and protein on hu-man normal gastric tissues, gastric cancer tissues and normal human gastric epithelial cells GES1, gastric cancer cells SGC-7901 and multidrug resistance of gastric cancer cells SGC-7901/DDP. siRNA GRP78 were transfected into SGC-7901/DDP cells by LipfectamineTM2000, and the siRNA group and control group without transfection were set up in the control cells. Real-time PCR and Western blotting SGC-7901/DDP methods were used to detect the transfection efficiency;changes of growth activity of SGC-7901 cells and cells proliferation inhibition rate of different concentrations of cisplatin DDP were detected by MTT method; apoptosis of SGC-7901 cells was measured by flow cytometry. Results The ex-pressions of GRP78 gene mRNA and protein in gastric cancer tissues were significantly higher than those in normal gas-tric cancer ( P<0 . 05 ); the expressions of GRP78 mRNA and protein of multi-drug resistance in gastric cancer SGC-7901/DDP cells were significantly higher than those in SGC-7901 gastric cancer cells and normal gastric epithelial cells GES1 ( P<0 . 05 );the expressions of GRP78 mRNA and protein were decreased significantly in SGC-7901/DDP cells transfected with GRP78 siRNA (P<0. 05);compared with control group and control siRNA group, cells growth activity was significantly decreased in GRP78 siRNA transfected SGC-7901/DDP group, cells proliferation inhibition rate and apoptosis rate were significantly increased ( P<0 . 05 ) . Conclusion GRP78 mRNA and protein show high expressions in gastric cancer and in multidrug resistance of gastric cancer cells SGC-7901/DDP, GRP78 plays a role in promoting cancer gene in gastric cancer. siRNA GRP78 transfection can silence the expression of GRP78 gene in SGC-7901/DDP cells, inhibit the proliferation of SGC-7901/DDP cells and promote cell apoptosis.%目的 研究内质网分子伴侣葡萄糖调节蛋白78(glucose regulated protein 78,GRP78)在人不同胃组织(正常胃组织和胃癌组织)和细胞(正常胃上皮GES1细胞、胃癌SGC-7901细胞、多耐药性胃癌SGC-7901/DDP细胞)中的表达水平;揭示GRP78沉默表达对SGC-7901/DDP细胞增殖和凋亡的影响.方法 利用实时荧光定量PCR(Real-time PCR)和免疫印迹(Western blotting)方法 分别检测人正常胃组织、胃癌组织、人正常胃上皮GES1细胞、胃癌SGC-7901细胞、多耐药性胃癌SGC-7901/DDP细胞中GRP78 mR-NA和蛋白表达水平.利用LipfectamineTM2000将GRP78 siRNA转染至SGC-7901/DDP细胞中,同时设置未转染Control组和无义转染Control siRNA组.Real-time PCR和Western blotting方法 检测各组SGC-7901/DDP细胞转染效率;MTT方法 检测各组SGC-7901细胞的生长活力变化和不同浓度顺铂DDP作用下细胞增殖抑制率;流式细胞术检测各组SGC-7901细胞凋亡情况.结果 胃癌组织中GRP78 mRNA和蛋白表达水平显著高于正常胃组织(P<0.05);多耐药性胃癌SGC-7901/DDP细胞中GRP78 mRNA和蛋白表达水平显著高于胃癌SGC-7901细胞和正常胃上皮GES1细胞(P<0.05);GRP78 siRNA转染SGC-7901/DDP细胞后GRP78 mRNA和蛋白表达水平显著下降(P<0.05);与Control组和Control siRNA组相比,GRP78 siRNA转染组SGC-7901/DDP细胞生长活力显著下降,DDP作用下细胞增殖抑制率和细胞凋亡率显著增加(P<0.05).结论 GRP78 mRNA和蛋白在胃癌组织中高表达,在多耐药性胃癌SGC-7901/DDP细胞中也高表达,证实GRP78在胃癌中发挥促癌基因的作用.而GRP78 siRNA转染能够沉默SGC-7901/DDP细胞中GRP78基因表达,抑制SGC-7901/DDP细胞增殖并促进细胞凋亡.