幽门螺杆菌cagA基因影响胃粘膜上皮细胞肿瘤相关蛋白表达  

Cytotoxin-associated gene A of Helicobacter pylori affects cancer-related protein expression in gastric epithelial Ges-1 cells

作　　者：黄志刚[1] 段广才[2] 唐焕文[1] 胡利人[1] 杜进林[1] 潘海燕[1] 

机构地区：[1]广东医学院公共卫生学院流行病学教研室,广东东莞523808 [2]郑州大学公共卫生学院流行病学教研室

出　　处：《中国公共卫生》2010年第7期881-883,共3页Chinese Journal of Public Health

基　　金：河南省创新人才基金资助项目(2000-84);广东医学院博士启动项目

摘　　要：目的筛选和鉴定与幽门螺杆菌(Hp)细胞毒素相关基因A(cagA)有关的宿主细胞肿瘤相关蛋白。方法用幽门螺杆菌野生株和cagA基因敲除株分别与胃粘膜上皮细胞Ges-1共培养10h(细菌与细胞的比例为100:1),提取2组细胞总蛋白,进行等电聚焦和十二烷基磺酸钠-聚丙烯酰胺凝胶(SDS-PAGE)电泳,比较2组细胞蛋白质表达谱差异,选取差异蛋白点进行质谱分析鉴定。结果经肽质量指纹图(PMFs)检索分析鉴定,与cagA基因敲除株比对,幽门螺杆菌野生株攻击后的胃粘膜上皮细胞Ges-1总蛋白中的磷酸丙糖异构酶、膜联蛋白A1和α-烯醇酶(2个相邻位点)4个差异蛋白点均呈高表达,质谱评分依次为:325,254,395,347;肽段匹配率分别为:95%,79%,77%,76%。结论 3种差异表达的蛋白均与幽门螺杆菌cagA基因有关,属于胃粘膜上皮细胞肿瘤相关蛋白。Objective To screen and identify the cancer-related proteins in host cells with relation to cagA gene of Helicobacter pylori（H pylori）.Methods Gastric epithelium cell line Ges-1 cells were co-cultured with the wild-type strains Hp 27 and the isogenic cagA-deleted mutants Hp 27△ cagA at a ratio of 100：1 for the bacteria and the cells in culture medium for 10 hr.Total cellular proteins of two groups were extracted with Sonication-Urea-CHAPS-DTT method and the protein concentration was measured with Bradford＇s method.The soluble proteins of two groups were separated firstly by isoelectric focusing（IEF） electrophoresis and then by SDS-PAGE to obtain 2-DE maps,which were digitalized and analysed to search the protein spots of differential expression.Spots of interest were cut out and subjected to in-gel digestion.Then the peptide mass finger-printer（PMF） was obtained with matrix assisted laser adsorption ionization time of flight mass spectrometry（MALDI-TOF-MS）.Then the biology information was used to search protein database of these PMF and to identify the proteins,and analyze the biological significance and function of the proteins.Results Four protein spots of differential expression,which were high abundance in the cellular proteins of wild-type strain group and were down-regulated or absently expressed in the proteins of mutant group,were selected and identified.The identified proteins were triosephosphate isomerase,annexin A1 and a-enolase,which were reported to have close relationship with the pathophysiological processes of many kinds of cancers.Conclusion Three tumor marker proteins of triosephosphate isomerase,a-enolase and annexin A1 are associated with cagA gene of H pylori.The result suggests that the cagA gene is involved in the carcinogenesis of H pylori.

关 键 词：幽门螺杆菌(Hp) 细胞毒素相关基因A(cagA) 胃粘膜上皮细胞 蛋白质组 

分 类 号：R735[医药卫生—肿瘤]