幽门螺杆菌在胃癌发生过程中的作用机制

【关键词】 胃肿瘤

Role of Helicobacter pylori in development of gastric cancer

　　【Abstract】 AIM: To study the possible carcinogenesis of Helicobacter pylori(Hp) infection in the development of gastric cancer. METHODS: Hp was determined by WarthinStarry silver staining in 39 samples of gastric cancer tissue, 24 samples of gastric mucosal atypical hyperplasia tissue and 33 samples of chronic gastritis tissue. HpcagA was determined by polymerase chain reaction (PCR) and the expressions of iNOS, VEGF, p185 and p21 were examined by SP immunohistochemical staining. RESULTS: The expressions of Hp, HpcagA, iNOS, VEGF, p185 and p21 in gastric mucosal atypical hyperplasia and gastric cancer tissue were significantly higher than those in chronic gastritis. The expressions of iNOS, VEGF and p21 in Hp positive chronic gastritis, gastric mucosal atypical hyperplasia and gastric cancer cases were significantly higher than those in Hp negative cases. The expression of p185 in Hp positive gastric mucosal atypical hyperplasia and gastric cancer cases was significantly higher than that in Hp negative cases. The expression of Hp was positively related with iNOS, VEGF and p21 in chronic gastritis, gastric mucosal atypical hyperplasia and gastric cancer cases. The expression of Hp was positively related with p185 in gastric mucosal atypical hyperplasia and gastric cancer cases. CONCLUSION: Hp infection leads to the overexpression of HpcagA, iNOS and VEGF, which can stimulate the higher expressions of oncogene cerbB2 and ras. It may be one of the crucial mechanisms of induction of gastric cancer by Hp.

　　【Keywords】 stomach neoplasms; vascular endothelial growth factors; nitric oxide synthase; oncogene; helicobacter pylori; cytotoxin associated gene

　　【摘要】 目的： 探讨Hp可能的致癌机制. 方法： 采用WarthinStarry嗜银染色法检测胃癌组织39例，胃黏膜不典型增生24例和慢性胃炎组织33例中的Hp感染情况；采用PCR法检测上述标本中HpcagA；采用免疫组化SP法检测组织中iNOS, VEGF, cerbB2和ras癌基因产物p185和p21的表达. 结果： Hp, HpcagA, iNOS, VEGF, p185和p21在不典型增生和胃癌组织中的表达显著高于慢性胃炎组织；Hp阳性慢性胃炎、不典型增生和胃癌组织中iNOS, VEGF和p21的表达显著高于Hp阴性组，Hp阳性不典型增生及胃癌组织中p185的表达显著高于Hp阴性组；慢性胃炎、不典型增生和胃癌组织中Hp与iNOS，VEGF和p21表达呈正相关，不典型增生和胃癌组织中Hp与p185表达呈正相关. 结论： Hp的致癌作用与其HpcagA的过度表达，增强胃黏膜细胞中iNOS和VEGF的表达，促进胃黏膜细胞癌基因cerbB2和ras的活化密切相关. 本文来自中国科教评价网

　　【关键词】 胃肿瘤；血管内皮生长因子类；一氧化氮合酶；癌基因；螺杆菌，幽门；细胞毒素相关基因

　　0引言

　　幽门螺杆菌（Helicobacter pylori, Hp）感染与胃癌的发生发展密切相关［1，2］，但Hp确切的致癌机制尚不清楚. 我们通过对慢性胃炎、胃黏膜不典型增生及胃癌组织中Hp和细胞毒素相关基因（cytotoxin associated gene A, cagA）阳性株感染率，诱导型一氧化氮合酶（inducible NOS, iNOS），血管内皮生长因子（vascular endothelial growth factor, VEGF），cerbB2和ras癌基因产物p185和p21蛋白表达情况及Hp与iNOS, VEGF, p185和