What are the Mechanisms of DNA Methylation in Cancer?
The primary enzyme responsible for adding methyl groups to DNA is DNA methyltransferase (DNMT). In cancer cells, the activity of DNMTs can become altered, leading to global hypomethylation and localized hypermethylation. Global hypomethylation can cause genomic instability, while hypermethylation of promoter regions can silence critical tumor suppressor genes.