Expression of Dnmt1 gene mRNA and protein in gastric carcinoma

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(χ2=30.694,P0.01).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(P0.001).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(P0.05).Spearman rank correlation analysis indicated that the expression of Dnmt1 mRNA was positively correlated with its protein(rs=1.000,P0.01).CONCLUSION:The increased expression of Dnmt1 mRNA and its protein is closely associated with the occurrence development and lymph nodes metastasis of gastric carcinoma.