OICR-9429 is a potent antagonist of the interaction that WDR5 effect with peptide regions of MLL and Histone 3. It reduces the viability of acute myeloid leukemia cells in vitro.

OICR-9429 binds WDR5 with high affinity (Kd=93±28 nM) and competitively disrupts its interaction with a high-affinity Wdr5-interacting (WIN) peptide of MLL (Kdisp=64±4 nM)[1].

AR binding affinity: AR binding affinities of test compounds are studied in cytosolic lysates obtained from ventral prostates of castrated rats by a competition binding assay. Fresh prostates are minced and homogenized with Buffer A containing protease inhibitors. The homogenates are centrifuged and the resultant supernatants are treated with a dextran-coated charcoal solution to remove endogenous steroids. The dissociation constant of the radio ligand [3H]mibolerone for isolated rat ARs is determined in a saturation binding experiment. For the determination of Ki values, prostate cytosol preparations and 1?nM [3H]mibolerone are incubated with increasing concentrations of test compounds overnight. After the incubation, bound and free steroids are separated by treatment with 100?μL of dextran-coated charcoal suspension. Bound radioactivity is determined by counting 100?μL of supernatant fraction in 200?μL of scintillation fluid using a microbeta counter. All procedures are carried out at 0–4?°C.

20,000 viable, actively proliferating primary human AML cells per well were seeded in 96-well plates in triplicates and treated with 0.05% DMSO or OICR-9429. Cell viability was measured using the Cell Titer-Glo luminescent cell viability assay on a VICTOR X4 luminometer after 72 h.(Only for Reference)