Expression and promoter hypermethylation status of RASSF1A in gastric cancer

Objective: To investigate promoter methylation,expression of RASSF1A gene and their correlationship in gastric cancer.Methods: Immunohistochemistry was employed to detect the expression of RASSF1A gene in gastric cancer tissues and their adjacent tissues from 39 patients,and in 30 specimens of normal.And Methylation-specific polymerase chain reaction was used to detect promoter methylation of RASSF1A gene in every tissue.Results: RASSF1A protein expressions in GC were reduced significantly than those in corresponding non-neoplastic tissues and normal controls(53.8% vs.97.4% and 100%,P0.05).The positivity rate of promoter methylation of RASSF1A gene was significantly higher in gastric cancer than that in corresponding non-neoplastic tissues and normal controls(64.1% vs 7.7% and 0%,P0.05).Furthermore,RASSF1A expression in methylation group of gastric cancer was much reduced than that in unmethylation group of gastric cancer(P0.05).Conclusion: Expression of RASSF1A is reduced in the tissue of gastric cancer.Low expression of RASSF1A is associated with promoter hypermethylation of RASSF1A gene.RASSF1A promoter methylation is closely associated with the oncogenesis of gastric cancer.