胃癌组织中Dnmt1基因mRNA和蛋白的表达

Expression of Dnmt1 gene mRNA and protein in gastric carcinoma

目的:探讨正常胃黏膜、不典型增生胃黏膜及胃癌组织中Dnmt1基因mRNA及蛋白的表达以及两者之间的关系.方法:应用原位杂交技术及免疫组化SP法检测20例正常胃黏膜、40例不典型增生胃黏膜及60例胃癌组织中Dnmt1基因mRNA及蛋白的表达状况.结果:Dnmt1 mRNA在正常胃黏膜腺上皮中基本呈阴性表达(除部分增生的小凹上皮),其阳性率在正常胃黏膜、不典型增生胃黏膜及胃癌三组间呈递增趋势,组间有统计学差异(P<0.01).Dnmt1蛋白在正常胃黏膜腺上皮中基本呈阴性表达(除部分增生的小凹上皮和淋巴细胞),其阳性率在正常胃黏膜、不典型增生胃黏膜及胃癌三组间呈递增趋势,组间有统计学差异(P<0.01).Dnmt1 mRNA和蛋白的阳性表达与年龄、性别、肿物的大小、浸润深度、有无脉管转移等临床病理特征无关,而与有无淋巴结转移有关(P<0.05).Spearman等级相关分析显示Dnmt1蛋白与mRNA表达呈正相关(rs=1.000,P<0.01).结论:Dnmt1在胃癌组织中的高表达与胃癌的发生、发展及淋巴结转移密切相关.

AIM： To investigate the expression of Dnmt1 mRNA and its protein in normal gastric mucosa, atypical gastric hyperplasia, gastric carcinomas tissues and the relationship of both expression. METHODS： The expression of Dnmt1 mRNA and protein were respectively detected by SP immunohistochemistry and in situ hybridization in normal gastric mucosa （ n = 20 ）, atypical gastric hyperplasia （n = 40 ） and gastric carcinomas tissues （ n = 60）. RESULTS： The positive expression of Dnmt1 mRNA was negative expression in normal gastric mucosa （except proliferative zones of foveolar epithelia）. The positive expression rates of Dnmt1 mRNA were gradually increased in normal gastric mucosa, atypical gastric hyperplasia and gastric carcinoma with statistical differences （ X^2 = 30. 694, P 〈 0. 01 ）. The positive expression of Dnmt1 protein in normal gastric mucosa was 0% （except proliferative zones of foveolar epithelia and lymphocytes）. The positive rates of Dnmt1 protein were also gradually increased in normal gastric mucosa, atypical gastric hyperplasia and gastric carcinomas, and statistical difference among the 3 groups（P〈0. 001）. In cases of gastric carcinoma, there was no significant correlation between the expression of Dnmt1 mRNA, protein and the clinic pathological parameters of tumors： gender, ages, vessel invasion, invasion depths, whereas there was statistical significance in lymph nodes metastasis（ P 〈0.05 ）. Spearman rank correlation analysis indicated that the expression of Dnmt1 mRNA was positively correlated with its protein（ rn = 1. 000, P 〈 0.01 ）. CONCLUSION： The increased expression of Dnmt1 mRNA and its protein is closely associated with the occurrence development and Xymph nodes metastasis of gastric carcinoma.