Hypermethylation of the Myf-3 gene in human colorectal cancer.

Abnormal methylation of DNA is one of the earliest detectable changes in human tumors. We investigated hypermethylation of the Myf-3 gene, the human homolog of the mouse myogenic gene Myo-D1, in colorectal adenomas and adenocarcinomas. Histologically normal gut mucosa from colorectal cancer patients showed moderately higher levels of methylation than in other normal tissues. Varying degrees of Myf-3 hypermethylation were found in all five adenomas and eight adenocarcinomas examined. Carcinomas arising from within adenomas generally showed a decrease in both the heterogeneity and intensity of Myf-3 methylation. Regional hypermethylation of this gene therefore appears to be an early event in human colorectal neoplasia.