Background:

GSK503 is a potent inhibitor of EZH2.

Enhancer of zeste homolog 2 (EZH2) is a histone-lysine N-methyltransferase enzyme that catalyses trimethylation of lysine 27 in histone 3 (H3K27me3), and then induces chromatin compaction and consequently inhibits target genes transcription.

GSK503 is a potent EZH2 inhibitor with anticancer activity. In human melanoma cells, GSK503 significantly reduced H3K27me3 levels, induced G1 cell cycle arrest and slowed down cell growth [1].

In mice, GSK503 induced reversible weight loss by