胃癌组织PTEN蛋白、VEGF表达和血管形成的关系

目的研究胃癌组织中PTEN蛋白、血管内皮生长因子（VEGF）表达和血管形成的关系。方法采用免疫组织化学S-P法检测20例正常胃黏膜及80例胃癌组织中PTEN、VEGF、微血管密度（MVD）的表达。结果20例正常胃黏膜组织PTEN全部阳性表达，胃癌组织PTEN阳性率为52．5％（40／80）、PTEN蛋白表达水平与组织分化程度、淋巴结转移及TNM分期密切相关（P〈0．05），VEGF在正常胃黏膜阳性率为10％（2／20），胃癌组织阳性率为53．8％（43／80），二者差异有显著性（P〈0．01），VEGF表达与淋巴结转移及TNM分期密切相关（P〈0．05），胃癌组织MVD显著高于正常胃黏膜MVD（P〈0．01），MVD与胃癌组织浸润深度、分化程度、淋巴结转移及TNM分期密切相关（P〈0．01），胃癌组织中VEGF表达与MVD呈显著正相关（P〈0．01），PTEN蛋白表达水平与VEGF表达呈显著负相关（P〈0．01），PTEN蛋白表达水平与MVD呈显著负相关（P〈0．01）。结论PTEN蛋白表达与胃癌的临床病理特征密切相关，胃癌PTEN基因失活可能通过增加VEGF的表达来促进血管形成，导致肿瘤恶性进展。

Relationship between expression of PTEN,VEGF and angiogenesis in gastric cancer

Aim To study the relation among expression of PTEN and Vascular endothelial growth factor（VEGF） with angiogenesis in gastric cancers. Methods The expressions of PTEN protein, VEGF, MVD were examined with immunohistochemical S-P method in 20 specimens of normal gastric mucosa and 80 specimens of gastric carcinoma. Results All normal mucosas were positive for PTEN. In the 80 gastric carcinomas,52.5% （42/80） were positive for PTEN protein. The expression of PTEN was well associated with histological differentiation,lymph node metastasis and TNM stage （P 〈 0.05 ）. The expression rate of VEGF was 10% （2/20） in normal gastric mucosa and 53.8% （43/80） in gastric carcinomas. There was significant difference between the two groups （P 〈 0.01 ）. Expression of VEGF was well correlated with TNM stage and lymph node metastasis （ P 〈 0.05）. The MVD in gastric carcinomas was higher than that in normal gastric mucosa（ P 〈0.01 ）. The MVD was significantly related with the depth of tumor invasion , histological differentiation, lymph node metastasis and TNM stage（ P 〈 0.01 ）. A positive correlation was found between VEGF expression and MVD in gastric carcinoma（ P 〈 0. 01 ） and reverse correlation was found between PTEN and VEGF（ P 〈 0.01 ）. There was negative trend between PTEN expression and MVD in gastric carcinomas（P 〈 0.01 ）. Conclusion PTEN expression was well associated with the clinicopathologic characters of gastric carcinoma. Inactivation of PTEN gene in gastric cancers may promote angiogenesis through pathway of increasing VEGF expression, and thus induce tumor progression.