International Journal of Morphology
On-line version ISSN 0717-9502
LIMA, Eleonidas Moura et al. Study of Methylation Pattern of de Novo DNA Methyltransferase Genes and its Correlation with DNA Methylation Pattern of RUNX3 in Individuals with Gastric Cancer from Northern Region of Brazil. Int. J. Morphol. [online]. 2007, vol.25, n.4, pp. 817-824. ISSN 0717-9502. doi: 10.4067/S0717-95022007000400022.
Gastric cancer is the forth malignancy in frequency in the world. In the northern Brazil is the second neoplasia most frequent in males and the third most frequent in females. Genetic and epigenetic alterations are evolved on gastric carcinogenesis and DNA methylation is the epigenetic alteration better studied. We analyzed de novo DNA methyltransferases methylation pattern and its association with RUNX3 gene methylation pattern in Brazilian samples of intestinal-type and diffuse-type of gastric cancer. PCR methylation specific was used to evaluate DNA methylation pattern. Sixty-six samples were studied in this work. Only the gene RUNX3 presented altered methylation pattern, being methylated in 38.5% of gastric cancer intestinal-type samples and in 70% of gastric cancer diffuse-type samples and, by this reason, it should be evolved in the genesis of this neoplasia. There was a statistically significant difference among diffuse-type and intestinal-type samples (p=0.0418) and among normal and tumour tissues (p<0.0001) for RUNX3 gene but not to DNMT3A, DNMT3B e DNMT3 genes on CpG islands analyzed. Alteration of RUNX3 methylation pattern is not associated to de novo alteration of DNA methyltransferases methylation pattern on studied regionsTherefore, it becomes necessary a better comprehension of this phenomenon on gastric carcinogenesis
Keywords : Methylation; de novo DNA methyltransferases; RUNX3; Gastric cancer.