Aberrant DNA Methylation of P16, MGMT, hMLH1 and hMSH2 Genes in Combination with the MTHFR C677T Genetic Polymorphism in Gastric Cancer

Abstract

Associations of P16, MGMT, hMLH1 and hMLH2 with gastric cancer and their relation with MTHFR statusin gastric patients who were confirmed with pathological diagnosis were assessed. Aberrant DNA methylationof P16, MGMT, hMLH1 and hMLH2 and polymorphisms of MTHFR C677T were assayed. The proportionalDNA hypermethylation in P16, MGMT, hMLH1 and hMLH2 in cancer tissues was significantly higher than inremote normal-appearing tissues. DNA hypermethylation of P16 and MGMT was correlated with the T and Nstages. Individuals with homozygotes (TT) of MTHFR C677T had significant risk of hypermethylation of MGMTin cancer tissues [OR (95% CI)= 3.47(1.41-7.93)]. However, we did not find association between polymorphismin MTHFR C677T and risk of hypermethylation in P16, MGMT, hMLH1 and hMLH2 genes either in canceror remote normal-appearing tissues. Aberrant hypermethylation of P16, MGMT, hMLH1 and hMLH2 couldbe predictive of gastric cancer.