UNC0638

UNC0638 selectively inhibits G9a and GLP histone methyltransferases with IC₅₀ of 15 nM and 19 nM, respectively. UNC0638 inhibits TNBC cell invasion and migration in vitro. UNC0638 is also an inhibitor of EHMT1/2 and induces fetal hemoglobin (HbF) expression in human erythroid progenitor cell culture. In addition, UNC0638 has anti-FMDV (foot-and-mouth disease virus) and anti-VSV (vesicular stomatitis virus) activities, with excellent potency and selectivity against multiple epigenetic and non-epigenetic targets^{[1][2][3][4][5]}. IC50 & Target:IC50: <15 nM (G9a), 19±1 nM (GLP)^[1] In Vitro: UNC0638, an inhibitor of G9a and GLP with excellent potency and selectivity over a wide range of epigenetic and non-epigenetic targets.The K_i of UNC0638 is determined to be 3.0±0.05 nM (n=2). Consistent with this, the Morrison K_i for UNC0638 is 3.7±0.2 nM (n=3). The selectivity of UNC0638 over a wide range of epigenetic targets is evaluated. Notably, UNC0638 is inactive against other H3K9 (SUV39H1 and SUV39H2), H3K27 (EZH2), H3K4 (SETD7, MLL and SMYD3), H3K79 (DOT1L) and H4K20 (SETD8) methyltransferases, as well as PRDM1, PRDM10 and PRDM12. In addition, UNC0638 is inactive against protein arginine methyltransferases PRMT1 and PRMT3, and HTATIP, a histone acetyltransferase. Of note, UNC0638 has weak but measurable activity against JMJD2E (IC₅₀=4,500±1,100 nM), a Jumonji protein demethylase and DNA methyltransferase DNMT1 (IC₅₀=107,000±6,000 nM). Nevertheless, the selectivity of UNC0638 for G9a and GLP over JMJD2E is >200-fold, and selectivity for G9a and GLP over DNMT1 is >5,000-fold^[1]. UNC0638 is a type of small molecule that can specifically inhibit the enzyme activity of histone methyltransferase EHMT and reduce the H3K9 dimethylation (H3K9me2) levels in cells^[2].