The 3 patients (2 with ulcerative colitis and 1 with Crohn ileo-colitis) were evaluated for a variety of clinical, histologic (including the type, location and number of polyps in the colon), and immunohistochemical features [MLH-1, MSH-2, MGMT (O(6)-methylguanine-DNA methyltransferase), beta-catenin, and p53].
The frequency of MGMT and hMLH1 methylation in UC-associated tumors was low, with a significant difference between HGD and sporadic adenomas with HGD of the left hemicolon.
These findings indicated that promoter hypermethylation of the MGMT gene is infrequent in patients with UC, and may not closely contribute to UC-associated colorectal tumorigenesis.