Abstract: BACKGROUND AND AIM: To investigate the promoter methylation state of MGMT (O6_methylguanine DNA methyltransferase) gene and p16 gene in esophageal squamous cell carcinoma, and analyze the methylation frequencies of the two genes, thereby understanding the relationship between methylation of the promoters of MGMT gene and p16 gene in esophageal squamous cell carcinoma. MATERIALS AND METHODS: Methylation of the promoters of MGMT gene and p16 gene was evaluated by methylation_specific PCR in 44 esophageal carcinoma tissues, and carry out differential test and association analysis of the methylation frequencies of the two genes using χ2 test. RESULTS: Among the 44 esophageal squamous cell carcinomas, MGMT gene methylation was found in 18 cases and p16 gene methylation in 23 cases. Both MGMT and p16 gene methylation were present in 7 cases. Neither MGMT nor p16 gene methylation was detected in 10 cases. The difference of methylation frequencies of the two genes was insignificant(P>0.05). Differential test and association analysis of the methylation frequency of two genes was also insignificant. CONCLUSION: Methylation of the promoters of MGMT gene and p16 gene may both be closely associated with the initiation and progression of esophageal squamous cell carcinoma, but the methylations of the two genes took place independently.

Key words: esophageal squamous cell carcinoma, hypermethylation, epigenetics, MGMT gene, p16 gene