Detection of aberrant methylation as a tumor marker in serum of patients with gastric cancer.

BACKGROUND This study aimed to detect hypermethylation in serum DNA from patients with gastric cancer at various stages and to assess the assay for early detection of primary and recurrent disease. MATERIALS AND METHODS Preoperative serum samples were obtained from 109 patients with gastric cancer. Blood samples were subjected to methylation-specific polymerase chain reaction analysis to determine the methylation status of the promoter region of the p16 and E-cadherin genes. RESULTS Forty patients (37%) showed hypermethylation of the promoter region in one or both genes (p16, 20 patients; E-cadherin, 26 patients). Of 36 patients with early-stage gastric cancers, 10 (28%) showed aberrant methylated signals. No aberrant methylation was detected in the serum DNA from 10 healthy volunteers. CONCLUSION Aberrant promoter hypermethylation may prove useful as a new serum marker for gastric cancer.