Methylation of the p16 gene is frequently detected in lymphatic-invasive gastric cancer.

BACKGROUND: A tumor suppressor gene, p16, was found to harbor promoter methylation associated with the loss of protein expression in cancer cells, suggesting that p16 inactivation due to promoter methylation may be important for gastric tumorigenesis. PATIENTS AND METHODS: The methylation status of the p16 gene was examined in primary carcinomas and the corresponding normal tissues derived from 49 patients with gastric cancer using quantitative methylation-specific PCR (qMSP) and the correlation between the methylation status and the clinicopathological findings was evaluated. RESULTS: Aberrant methylation of the p16 gene was detected in 17 out of the 49 (34%) primary gastric carcinomas, suggesting that the aberrant methylation of p16 is frequently observed in gastric carcinomas. The clinicopathological data were then correlated with these results. Significant differences were observed with lymphatic invasion (p=0.046) and tumor site (p=0.010). CONCLUSION: p16 might act as a tumor suppressor in gastric carcinomas and appears to be more frequently methylated in lymphatic-invasive gastric carcinomas.