Correlation of p16 gene methylation with protein expression in gastric cancer and its clinical significance

Objective:To investigate the correlation of p16 gene methylation with protein expression in gastric cancer and its clinical significance.Methods:Methylation-specific polymerase chain reaction(MSP)was used to detected the CpG island methylation in promoter region of p16 gene in 28 gastric cancer tissues and corresponding adjacent tissues.The expression of p16 protein was examined by immunohistochemistry in these tissues.The relationship between the methylation status of p16 CpG island and clinical pathological parameters was analyzed.Results:The rate of methylation of p16 gene in gastric cancer tissues was higher than that in corresponding adjacent gastric tissues(P0.01).The methylation of p16 gene correlated with differentiation,depth of invation and lymph node metastasis(P0.05).The positive expression rate of p16 protein in gastric cancer tissues was lower than that in corresponding adjacent gastric tissues(P0.01).Methylation of p16 gene was negatively related with expression of p16 protein in gastric cancer tissues(r=-0.544,P=0.003).Conclusion:Gene silencing induced by promoter methylation of p16 gene has a close relationship with the tumorigenesis and development of gastric cancer.