G9D-4 is a first-in-class, potent, selective PRTOAC degrader of protein lysine methyltransferase G9a (EHMT2, KMT1C) with DC50 of 0.1 uM in PANC-1 cells, highly selective over GLP (DC50>10 uM).
G9D-4 selectively and effectively reduced the H3K9me2 in a dose-dependent manner in PANC-1 cells, and has no effect on the methylation at other prominent lysine positions.
G9D-4 has no influence on the CRBN neo-substrates such as GSPT1 and CK1α.
G9a-G9D-4-CRBN ternary complex formation is necessary for G9a degradation, NEDD8-activating enzyme inhibitor MLN4924 and proteasome inhibitor MG132 also hinders the ability of G9D-4 to induce G9a degradation.
G9D-4 effectively inhibits cell growth against a panel pancreatic cancer cells: KP-4, PANC-1, ASPC-1, HPAF-II, Panc10.05, SW1990, Panc08.13, Panc04.03, Panc05.04, and Panc02.03, also inhibits 22Rv1 cell growth with IC50 of 9.9 uM.
G9D-4 (10 uM) caused significant induction of apoptosis in a dose- and time-dependent manner, with downregulation of H3K9me2 and the upregulation of γH2AX and cleaved PARP in PANC-1 cells.
G9D-4 sensitizes MRTX1133 against KRASG12D pancreatic cell lines.