乏氧对胃癌细胞系MGC803细胞周期、乏氧相关基因和蛋白表达的影响  

Effect of hypoxia on cell cycleand gene and protein expression in gastric cancer cell line MGC803

作　　者：李建军[1] 李宏宇[2] 辛彦[3] 陈延治[1] 李光[1] 刘意[1] 张素敏[3] 吴东瑛[3] 

机构地区：[1]中国医科大学附属第一医院放疗科,辽宁省沈阳市110001 [2]沈阳军区总医院消化内科,辽宁省沈阳市110001 [3]中国医科大学附属第一医院肿瘤研究所第四研究室,辽宁省沈阳市110001

出　　处：《世界华人消化杂志》2004年第11期2539-2542,共4页World Chinese Journal of Digestology

基　　金：国家自然科学基金资助项目;No.30371607

摘　　要：目的:观察胃癌细胞系MGC803乏氧不同时间细胞周期、抑癌基因PTEN、线粒体ATP6(mtATP6)和线粒体Cyt-b (mtCyt-b)mRNA及VEGF、EGFR蛋白表达变化. 方法:将MGC803细胞(1.0×1010/L)施加乏氧(10 mL/L O2) 处理0,2,8,16,24 h.应用RT-PCR,Western blot, 流式细胞术对MGC803细胞进行检测. 结果:MGC803细胞乏氧0,2,8,16,24 h时ATP6 mRNA表达量为78.22%,69.28%,84.40%,39.84%, 42.52%;Cyt-b mRNA为83.40%,75.87%,64.57%, 79.05%,77.44%:PTEN mRNA为23.93%,26.52%, 35.74%,40.31%,49.92%;VEGF蛋白表达量为16.1, 16.5,18.2,20.6,27.5;EGFR蛋白为14.3,17.2, 18.1,32.6,37.7.结果显示乏氧后ATP6 mRNA表达水平下降,8 h后又升高,以后随着时间的延长,ATP6 mRNA 再次下降;Cyt-b mRNA乏氧8 h出现一过性下降,24 h又恢复到乏氧前水平;PTEN mRNA、VEGF和EGFR蛋白表达水平随乏氧时间延长也逐渐增加,乏氧24 h表达最高; 乏氧使MGC803细胞发生G1期阻滞,凋亡细胞增多,S期细胞减少,但24 h后细胞周期分布基本恢复至乏氧前水平, 乏氧时间与MGCS03细胞周期的改变无相关性(P>0.05). 结论:乏氧使MGC803细胞发生一过性G1期阻滞,增加PTEN mRNA和VEGF、EGFR蛋白表达,降低mtATP6 mRNA的表达.AIM: To investigate the effect of hypoxia on cell cycle, expression of mitochondrion ATP6 (mtATP6), mitochondrion Cyt-b (mtCyt-b), PTEN mRNA, vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) protein in human gastric cancer cell line MGG803. METHODS: The MGC803 cells were exposed to anoxic environment for 0, 2, 8, 16, 24 h. The cell cycle was measured by flow cytometry, and the expression of mtATPG, mtCyt-b and PTEN mRNA was detected by reverse transcription polymerase chain reaction (RT-PCR). Expression of VEGF and EGFR protein was determined by Western blot assay. RESULTS: At 0, 2, 8, 16, and 24 h hypoxia, the rates of ATP6 mRNA expression of MGC803 cells were 78.22%, 69.28%, 84.40%, 39.84% and 42.52% respectively; Cyt-b mRNA expression was 83.40%, 75.87%, 64.57%, 79.05% and 77.44% respectively; PTEN mRNA expression was 23.93%, 26.52%, 35.74%, 40.31% and 49.92% respectively; VEGF protein expression was 16.1, 16.5, 18.2, 20.6, 27.5 and EGFR protein expression was 14.3, 17.2, 18.1, 32.6 and 37.7 respectively. The expression of PTEN mRNA, VEGF and EGFR proteins in vitro increased with the extending of hypoxia time. Expression of mtATP6 mRNA at 24 h was significantly reduced as compared with that under normal oxygen condition, and mtCyt-b mRNA was transiently reduced at 8 h but returned to normal level at 24 h. The MGC803 G1 phase cells and apoptotic cells transiently increased after hypoxia as compared with those under normal oxygen condition. However, distribution of cell cycle at 24 h was similar to that under normal oxygen condition. There was no significant relation between hypoxia time and changes of cell cycles (P>0.05). CONCLUSION: Hypoxia transiently prolongs MGC803 G1 phase and increases apoptotic rate of MGC803 cells. It up-regulates the expression of PTEN mRNA, VEGF and EGFR protein, and down-regulates the expression of mtATP6 mRNA.

关 键 词：乏氧 胃癌细胞系 MGC803 细胞周期 蛋白表达 

分 类 号：R735.2[医药卫生—肿瘤]