外源性NO诱导胃癌SGC-7901细胞凋亡的作用机制  

Mechanism underlying exogenous nitric oxide induced gastric cancer SGC-7901 cell apoptosis

作　　者：范丽丽[1] 李伟华[2] 

机构地区：[1]宁夏医科大学检验学院,宁夏回族自治区银川市750003 [2]甘肃省人民医院中心实验室,甘肃省兰州市730000

出　　处：《世界华人消化杂志》2015年第1期8-15,共8页World Chinese Journal of Digestology

基　　金：甘肃省科技支撑项目;No.090NKCA098~~

摘　　要：目的:探讨外源性一氧化氮(nitric oxide,NO)诱导中分化胃癌细胞株(SGC-7901)凋亡的潜在机制.方法:采用不同浓度的外源性NO供体硝普钠(sodium nitroprusside,SNP)处理细胞,M T T法检测细胞的存活率;荧光显微镜检测细胞的凋亡形态及凋亡率.依据有无活性氧(reactive oxygen species,ROS)抑制剂N-乙酰半胱氨酸(N-acetyl-L-cysteine,NAC)和SNP作用细胞,实验分4组:对照组、NAC组、SNP组、NAC+SNP组.采用荧光化学发光仪检测胞内ROS水平;流式细胞仪检测细胞的凋亡;Western blot检测铜锌超氧化物歧化酶(Cu/Zn-superoxide dismutase,Cu/ZnS O D)蛋白的表达.所有数据采用S P S S17.0分析.结果:(1)SNP可诱导胃癌细胞凋亡,且有浓度及时间依赖性;(2)NAC组和对照组在细胞凋亡率及胞内ROS水平上差异无统计学意义(P>0.05);(3)较对照组,单独SNP可使细胞凋亡率及胞内ROS水平明显升高(P<0.05);而经NAC干预后,SNP引起的细胞凋亡率和胞内ROS水平均下降(P<0.05),但仍高于对照组;(4)SNP可引起细胞Cu/Zn-SOD蛋白表达的降低.结论:外源性NO可通过抑制胃癌细胞Cu/ZnSOD蛋白的表达而上调其ROS水平,该功能可能参与其诱导的胃癌细胞凋亡途径.AIM： To investigate the potential mechanism of exogenous nitric oxide （NO） induced apoptosis of moderately differentiated gastric cancer cells （SGC-7901）. METHODS： SGC-7901 cells were treated with different concentrations of sodium nitroprusside （SNP）, which was used as the donor of exogenous NO. The survival rate of cells was detected by MTT assay. Cells were divided into four groups： a blank control group, a reactive oxygen species （ROS） inhibitor （N-acetyl-L-cysteine, NAC） group, an SNP group and an NAC ＋ SNP group. Apoptotic cell morphology and apoptosis rate were evaluated by fluorescence microscopy. Levels of ROS were determined by fluorescent chemiluminescence. Protein levels of Cu/Zn-superoxide dismutase （Cu/Zn-SOD） were detected by Western blot analysis. RESULTS： SNP induced apoptosis of SGC-7901 cells in a dose- and time-dependent manner. There were no significant differences in cell apoptosis rate or ROS level between the NAC group and blank control group （P 〉0.05）. Compared to the blank control group, cell apoptosis rate and ROS were significantly increased in the SNP group and NAC ＋ SNP group （P 〈 0.05）. Cell apoptosis rate and ROS level were significantly increased in the SNP group compared to the NAC ＋ SNP group （P 〈 0.05）. SNP decreased Cu/Zn-SOD protein expression in SGC-7901 cells.CONCLUSION： Exogenous NO can up-regulate ROS level in gastric cells by inhibiting Cu/Zn- SOD protein expression, which may be related to the mechanism by which NO induces apoptosis of gastric cancer cells.

关 键 词：胃癌 外源一氧化氮 细胞凋亡 活性氧 

分 类 号：R735.2[医药卫生—肿瘤]