The expression of DNA methyltransferase,demethylase and tumor-associated genes in human gastric cancer / 中华消化杂志

ABSTRACT

Objective To investigate the relationship of the expression of DNA methyltransferase,demethylase(mbd2) and tumor-associated genes in human gastric cancer. Methods Tissue samples of cancerous,para-cancerous and normal gastric mucosa were obtained surgically from 28 primary gastric cancer patients. The transcription level of DNA methyltransferase 1 (DNMT1),mbd2,methyl-CpG binding protein (MeCP2),p16 INK4A and c-myc were determined by using real-time RT-PCR and RT-PCR. The relationship between the expression of DNA methylation-associated genes and tumor-associated genes was analyzed. Results The mRNA level of DNMT1 was higher and the mRNA level of mbd2 gene was lower in cancerous tissue than that in normal tissue. The expression of c-myc instead of p16 INK4A and MeCP2 was increased in cancer tissues. The mRNA level of c-myc related negatively to mbd2 when gastric cancer developed. However,there was no any close relation between the transcription level of all above genes and tumor biological behavior in human gastric cancer. Conclusion This study indicates that MeCP2 but not DNMT1 may contribute to the regulation of tumor-associated genes expression in human gastric cancer.