DNA methylation: An important mechanism in colorectal carcinogenesis and pretumor progression

Abstract

Colorectal cancer is the third most common cancer diagnosed in both men and women in the United States, afflicting more than 100.000 people every year. Colorectal carcinogenesis is one of the most well-understood cancer pathways and, as with all cancers, is described by the accumulation of mutations and aberrations of the DNA. The adenoma-carcinoma sequence provides a distinct sequential mechanism for this accumulation, and has been investigated thoroughly in the past decades. The role of methylation events in colorectal carcinogenesis is a recent discovery and implies that epigenetic aberrations might provide and alternative method for genetic silencing. Furthermore, DNA methylation might play and important role in altering a stem cell without displaying phenotypical change. This process is called pretumor progression and the author investigated such methylation patterns in Barrets esophagus patients. Conclusions could not be made due to lack of sufficient samples.