The Study Of Mechanism Of Change In Runx3 In Gastric Carcinoma And Its Difference With P53 Mutation

The RUNX3 gene is a member of the Runt domain family of transcription factors that are master regulators of gene expression in major developmental pathways. Recently, lack of RUNX3 function was found to be associated with genesis and progression of gastric carcinoma. Li studied methylation of CpG islands in the RUNX3 gene by methylation-specific PCR in 80 gastric carcinoma specimens, 45 corresponding non-neoplastic mucosae, and 7 gastric carcinoma cell lines. Hypermethylation of the RUNX3 promoter was found in 57 (71%) of 80 gastric carcinomas, and promoter hypermethylation of RUNX3 occurred more frequently in intestinal and diffuse-adherent type tumors than in diffuse-scattered type tumors (p=0.046). Reduced RUNX3 expression was associated with promoter hypermethylation (p=0.036), In corresponding non-neoplastic mucosae, hypermethylation of the RUNX3 promoter was found in 38 (84%) of 45 specimens. The results overall suggest that transcriptional inactivation of RUNX3 by promoter hypermethylation may participate in the stomach carcinogenesis. To observe the mechanism of the change in runx3 in gastric carcinoma and its difference and with p53 mutation. We have taked A total of 30 cases of gastric carcinoma and 15 cases of normal gastric from clinical operation. PCR-SSCP methodwas used to detect mutations in exons 2-4 of runx3 gene in the gastric carcinoma ,The methylation status of runx3 gene was examined by methylation-specific polymerase chain reaction (MS-PCR), PCR- SSCP method was used to detect mutations in exons 5-8 of p53 gene in the gastric carcinoma. The results is that 2 cases with mutation were found ,Methylation of runx3 promoter region was confirmed in 87% (26/30) specimens of gastric carcinoma and in 20%(3/15) specimens of normal gastric, the rate of methylation of runx3 of gastric carcinoma was higher than the rate of normal gastric. 53.3%(16/30) cases were confirmed with mutation in the p53 gene. the rate of methylation of runx3 was higher than the rate of mutation of p53 (P<0.05). we conclusion that The gene mutation of runx3 is not the change of the molecular biology of gene in the gastric carcinoma.High frequent methylation in the promoter region of runx3 is primary change in the gastric carcinoma , compared with the mutation in the p53 gene, high frequent methylation in the promoter region of runx3 has genetic specificity and is pivotal gene in the development of gastric carcinoma.