结肠腺瘤性息肉病基因蛋白在二甲肼诱导大鼠大肠癌过程中的表达

摘要

Objective To observe the eXpression of APC protein in the formation process of colorectal carcinoma induced by 1, 2 -dimethylhydrazine to provide the new thought for its targeted therapy and early diagnosis. Methods SiXty male Sprague Dawley rats were randomly divided into the control group and the model group. The eXpression of APC protein in the intestinal mucosal tissue in 20 cases of colorectal cancer, 20 cases of colorectal adenoma and 20 cases of normal control was eXamined by the streptavidin - peroXidase (SP) immunohistochemistry. Results The immunohistochemical detection results displayed that the APC protein showed the strongly positive eXpression in normal colorectal mucosa tissue and had no eXpression in colorectal adenoma tissue and colorectal cancer tissue;the Western - blot assay results displayed that the specific band with a relative molecular weight of about 300 × 103 was seen in the normal colorectal tissue, but colorectal adenoma and colorectal cancer had no this band. Conclusion APC protein shows the non - eX-pression status in colorectal adenoma and colorectal carcinoma tissues, but is strongly eXpressed in the normal colorectal mucosal tissue, which suggesting that APC protein may be closely related with the occurrence and development process of colorectal cancer and is eX-pected to become the tumor marker of colorectal cancer.%目的：观察结肠腺瘤性息肉病基因（APC）蛋白在二甲肼诱导大鼠大肠癌形成过程中的表达，为大肠癌的靶向治疗和早期诊断提供新思路。方法将雄性 SD 大鼠60只随机分为正常对照组和模型组，应用免疫印迹法和免疫组织化学 SP 法，检测20例大肠癌组、20例大肠腺瘤组及20例正常对照组大鼠大肠黏膜组织中 APC 蛋白的表达情况。结果免疫组织化学检测结果显示，APC 蛋白在正常对照组大鼠大肠黏膜组织中均呈强阳性表达，在大肠腺瘤和大肠癌组大鼠大肠组织中未见表达；免疫蛋白印迹检测结果显示，正常大肠黏膜组织均表现为包含有1条相对分子质量约为300×103的特异性条带，而大肠癌和大肠腺瘤黏膜组织却均不含有该条带。结论APC 蛋白在大肠腺瘤和大肠癌组织中呈不表达状态，而在正常大肠黏膜组织中呈强表达状态，提示其与大肠癌的发生、发展过程关系密切，可望成为大肠癌的肿瘤标志物。