Cheryl H Arrowsmith, PhD

Epigenetics refers to heritable differences in phenotype that are due to mechanisms other than differences in DNA sequence. Epigenetics involves a dynamic interplay between DNA methylation, posttranslational modification of histones and other proteins, and noncoding RNA networks that control gene expression programs in normal and diseased cells.

Mutations in chromatin regulatory genes and alterations of the cellular epigenome are prevalent in most cancers. Post-translational modifications (PTMs) on histone proteins serve as docking sites for chromatin-associated proteins, which in turn dictate dynamic conversion between transcriptionally active or silent chromatin states. The combinatorial nature of these modifications establishes a "histone code" which serves to expand the information present in the DNA-sequence of the genetic code. Lysine methylation is the most complex mark, and it plays a pivotal role in heterochromatin formation, transcriptional regulation and X-chromosome inactivation. Mutations or aberrant expression of proteins containing these domains often leads to deregulation of histone lysine methylation, leading to various diseases, most notably, cancer.

We work with the Structural Genomics Consortium (SGC) to develop structure-based potent, selective, cell-active small molecule inhibitors of individual epigenetic regulatory proteins. These compounds, also referred to as chemical probes, are extremely valuable for understanding epigenetic signaling mechanisms in cells. Chemical probes are highly complementary to genetic methods and more closely mimic strategies for therapeutic translation. We are providing our epigenetic chemical probes as an Open Access resource to the biological research community to facilitate understanding of epigenetic mechanisms and to more rapidly identify and validate therapeutic targets for cancer and other diseases.