Modulation of DNA/RNA Methylation by Small-Molecule Modulators and Their Implications in Cancer.

Chromatin is an organized complex of DNA, histone proteins, and RNA. Chromatin modifications include DNA methylation, RNA methylation, and histone acetylation and methylation. The methylation of chromatin complexes predominantly alters the regulation of gene expression, and its deregulation is associated with several human diseases including cancer. Cancer is a disease characterized by dynamic changes in the genetic and epigenetic architecture of a cell. Altered DNA methylation by DNA methyltransferases (DNMTs) and m6A RNA methylation facilitate tumor initiation and progression and thus serve as critical targets for cancer therapy. Small-molecule modulators of these epigenetic targets are at the hotspots of current cancer drug discovery research. Indeed, recent studies have led to the discovery of several chemical modulators against these targets, some of which have already gained approval for cancer therapy while others are undergoing clinical trials. In this chapter, we will focus on the role of small-molecule modulators in regulating DNA/RNA methylation and their implications in cancer.