The Epigenome of Colorectal Cancer

Epigenetic alterations (eg, DNA methylation) play important roles in silencing cancer-related genes in colorectal cancers (CRCs). DNA methylation occurs in genes involved in cell cycle checkpoints, apoptosis, signal transduction, DNA repair, and maintenance of the genome's integrity. Recent developments of new methods for detecting DNA methylation have enabled us to create epigenetic profiles of CRC and to classify them into three distinct subgroups based on genetic and epigenetic alterations. DNA methylation also leads to silencing of some microRNAs, which in turn leads to dysregulation of oncogenic proteins, which are their targets. Moreover, for diagnosis, epigenetic information may be used to detect cancer cells in serum and stool. Obtaining a fuller understanding of the epigenome will be an important step toward understanding the molecular mechanisms underlying CRC and may provide the basis for the development of novel diagnostic tools and approaches to therapy.