Reduced Expression Of Runx3 Gene Expression In Gastric Cancer And Its Mechanism Study

Part I Mutatioin, deletion, methylation and expression of RUNX3 gene in gastric carcinomaObjective we research the relation between abnormal expression of RUNX3 gene and incidence of gastric carcinoma. This article examine expression of RUNX3 from level of mRNA and protein and detect the mutation, LOH and methylation of RUNX3 gene from level of DNA in gastric carcinoma. We evaluate the influence of abnormal expression of RUNX3 gene for incidence and progression of gastric carcinoma.Methods we analyse the expression state of mRNA of RUNX3 gene by RT-PCR. Usingwestern blot and S-P immunohistochemical method, we dectect the change of the level of RUNX3 protein in gastric carcinoma.Using MSP, PCR-SSCP and denaturing PAGE gel electrophoresis, we interpret the mutation, deletion and methylation of RUNX3 gene in the level of DNA in gastric carcinoma.Results The levels of RUNX3 protein were examined in gastric carcinoma and adjacent normal gastric tissue by imrnunohistochemistry. The RUNX3 protein staining was located on the cell nucleus and cytoplasm. The positive rates of RUNX3 protein expression were 51.13% in gastric carcinoma and 100% in normal gastric mucosa respectively. The positive rate of RUNX3 protein expression in gastric carcinoma was significantly lower than that in normal gastric mucosa. The positive rate of RUNX3 protein expression was 80.00% (12/15) in well differentiated, 53.84% (7/13) in moderate differentiated and 23.52% (4/17) in poor differentiated gastric carcinoma respectively, which indicated the expression of RUNX3 protein was related to the degree of differentiation of gastric carcinoma. The positive rate of RUNX3 expression in node-positive cases was 33.33% (7/21), which was significantly lower than that in node-negative cases 66.67% (16/24) .The expression of RUNX3 was related with lymph node metastasis.The levels of RUNX3 protein were examined in gastric carcinoma and adjacent normal gastric lesions by western blot. The levels of RUNX3 protein were 1.274±0.108 in normal gastric lesions, while in gastric carcinoma they were 0.495±0.161. The level of RUNX3...