Background:

IC50: 5 uM

OICR-9429 is an antagonist of Wdr5-MLL interaction.

WDR5 has been identified as a component of the MLL complex, which is required for histone H3 tri-methylation by its binding of histone H3. Thus, WDR5 is reported to be a presenter component of MLL, suggesting that WDR5 can bind substrates of methylated histone H3 to the MLL complex for further methylation.

In vitro: Previous study found that Wdr5 could be detected readily in C/EBPα immunoprecipitates from lysates of Cebpap30/p30 cells by the treatment of OICR-9429, indicating that the Wdr5-MLL interaction could not influence p30 binding. Moreover, the gene expression profiling of OICR-9429-treated Cebpap30/p30 cells showed that Wdr5 antagonism could result in the upregulation of myeloid-specific transcripts. In addition, the gene set enrichment analyses demonstrated a close correlation between OICR-9429–induced genes and genes that were upregulated after Wdr5 knockdown. Furthermore, the gene profile of Cebpap30/p30 LICs6 was downregulated due to the Wdr5 antagonism caused by OICR-9429. Further treatment of OICR-9429 to Cebpap30/p30 cells was found to be associated with myeloid differentiation and loss of progenitor morphology [1].

In vivo: So far, there is no animal in vivo data reported.

Clinical trial: Up to now, OICR-9429 is still in the preclinical development stage.

Reference:
[1] Grebien F et al.  Pharmacological targeting of the Wdr5-MLL interaction in C/EBPα N-terminal leukemia. Nat Chem Biol.2015 Aug;11(8):571-8.