MS67 is a potent and selective degrader of the WD40 repeat domain protein 5 (WDR5) with a dissociation constant (Kd) of 63 nM. It exhibits no activity against protein methyltransferases, kinases, G-protein-coupled receptors (GPCRs), ion channels, and transporters. Notably, MS67 demonstrates significant anticancer properties.

WDR5:63 nM (Kd)

MS67 (0.001-1 μM) induces WDR5 degradation at a concentration as low as 1 nM. MS67 induces WDR5 depletion much more effectively in all six mixed lineage leukemia (MLL)-r acute myeloid leukemia (AML) and four pancreatic ductal adenocarcinoma (PDAC) cell lines without a hook effect and in a concentration-dependent manner in PDAC cells[1]. MS67 decreases H3K4me2/3 in both MV4;11 and MIA PaCa-2 cells, whereas other examined histone methylation marks such as H3K9me3, H3K27me3, and H3K36me3 are not affected . MS67 is effective in suppressing both WDR5-related gene expression programs and WDR5/MLL-induced H3K4 methylations on chromatin[1]. The GI 50 values of MS67 in the two most sensitive AML lines, MV4;11 and EOL-1, are 15 nM and 38 nM, respectively. MLL-r acute leukemia cell lines including MV4;11, EOL-1, MOLM13, KOPN8, RS4;11, and THP-1 are sensitive to MS67, whereas leukemia cell lines that did not harbor MLL-r (including K562, HL60, and a murine AML line transformed by Hoxa9 plus Meis1) are insensitive to MS67[1]. .

MS67 binds to VCB (VHL-Elongin C-Elongin B ternary complex), with a K d of 140 nM[1]. Western Blot Analysis[1]Cell Line: MV4;11 cells Concentration: 0.001 μM, 0.005 μM, 0.01 μM, 0.05 μM, 0.1 μM, 0.5 μM, 1 μM Incubation Time: 18 hours Result: Induced WDR5 degradation at a concentration as low as 1 nM with DC 50 of 3.7 nM.

MS67 (75 mg/kg; i.p.; twice daily; 5 days a week; for 20 days) significantly inhibits tumor growth in vivo and prolongs survival of the treated mice[1]. After a single intraperitoneal (i.p.) injection of MS67 at a dose of 75 mg/kg, the Cmax reached at about 4.2 μM, and the concentration of MS67 retained above 0.5 μM over 12 hours[1]. Animal Model: MV4;11 MLL-r AML xenograft mouse[1]Dosage: 75 mg/kg Administration: i.p.; twice daily; 5 days a week; for 20 days Result: Inhibited tumor growth in vivo.