胃粘膜癌变过程中bc1-2、p^(53)和Rb基因的表达

The Expression of bcl-2, p^(53) and Rb Genes During Carcinogenesis of Gastric Mucosa

目的 研究胃粘膜癌变过程中bc1- 2、p53 和Rb的基因的表达及意义。方法 采用免疫组化方法对 5 0例胃癌 ,18例癌旁肠化生 ,7例癌旁轻中度异型增生及 9例重度异型增生组织中bc1- 2、p53 和Rb基因表达情况进行检测和比较。结果 正常胃粘膜上皮增殖带干细胞区bc1- 2蛋白呈弱阳性表达 ,异性增生病变中 ,bcl- 2蛋白表达率和表达强度明显大于肠化生病变和正常胃粘膜上皮 (P <0 .0 5 ) ,胃癌组织中表达减少 ,p53 蛋白和Rb蛋白仅在重度异型增生病变和胃癌组织中表达。结论 bcl-2蛋白的表达主要是在胃癌的启动和促进阶段起作用 ,而在已具有恶性表型的细胞中不起关键作用。p53 和Rb基因的改变可能发生在胃粘膜癌变的较后期阶段 ,使胃癌的细胞凋亡受抑。

Aim:To investigate the significance of the expresion of bc1-2, p 53 and Rb genes during the carcinogenesis of gastric mucosa. Methods:Immunohistochemical staining technique was used to observe bcl-2.p 53 and Rb gene expression in 50 cases of gastric carcinoma,of which 18 intestinal metaplasia(IM),l 7 mild/moderate atypical dysplasia(Dys)and 9 severe Dys (mucosa adja cent to the tumor).Results:In normal gastric mucosa,bcl-2 protein was faintly stained in the proliferative zone. The positive-staining rates and intensity of bcl-2 protein in Dys epithelium was significantly higher than those in IM and those in nomal gastric mucosa(P<0.05). In gastric cancer,bcl-2 protein expression was reduced. p 53 and Rb over-expression were found only in severe Dys epithelium. Conclusion: Over-pression of bcl-2 play an important role in the stages of initiation and promotion, it dose not play a crucial role in the progession of gastric carcinoma.Abmormalities of p 53 and Rb are a late event in gastric cacinogenesis, and can suppess cell apoptosis of gasfric carenoma.