High-affinity, small-molecule peptidomimetic inhibitors of MLL1/WDR5 protein-protein interaction.Karatas, H., Townsend, E.C., Cao, F., Chen, Y., Bernard, D., Liu, L., Lei, M., Dou, Y., Wang, S.
(2013) J.Am.Chem.Soc. 135: 669-682
- PubMed: 23210835
- DOI: 10.1021/ja306028q
- Primary Citation of Related Structures:
- PubMed Abstract:
Mixed lineage leukemia 1 (MLL1) is a histone H3 lysine 4 (H3K4) methyltransferase, and targeting the MLL1 enzymatic activity has been proposed as a novel therapeutic strategy for the treatment of acute leukemia harboring MLL1 fusion proteins. The MLL ...
Mixed lineage leukemia 1 (MLL1) is a histone H3 lysine 4 (H3K4) methyltransferase, and targeting the MLL1 enzymatic activity has been proposed as a novel therapeutic strategy for the treatment of acute leukemia harboring MLL1 fusion proteins. The MLL1/WDR5 protein-protein interaction is essential for MLL1 enzymatic activity. In the present study, we designed a large number of peptidomimetics to target the MLL1/WDR5 interaction based upon -CO-ARA-NH-, the minimum binding motif derived from MLL1. Our study led to the design of high-affinity peptidomimetics, which bind to WDR5 with K(i) < 1 nM and function as potent antagonists of MLL1 activity in a fully reconstituted in vitro H3K4 methyltransferase assay. Determination of co-crystal structures of two potent peptidomimetics in complex with WDR5 establishes their structural basis for high-affinity binding to WDR5. Evaluation of one such peptidomimetic, MM-102, in bone marrow cells transduced with MLL1-AF9 fusion construct shows that the compound effectively decreases the expression of HoxA9 and Meis-1, two critical MLL1 target genes in MLL1 fusion protein mediated leukemogenesis. MM-102 also specifically inhibits cell growth and induces apoptosis in leukemia cells harboring MLL1 fusion proteins. Our study provides the first proof-of-concept for the design of small-molecule inhibitors of the WDR5/MLL1 protein-protein interaction as a novel therapeutic approach for acute leukemia harboring MLL1 fusion proteins.
Department of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA.