Discovery and characterization of an iminocoumarin scaffold as an inhibitor of MEKK2 (MAP3K2)
- Department of Pharmaceutical Sciences, Biomanufacturing Research Institute and Technology Enterprise (BRITE), North Carolina Central University, Durham, NC (United States)
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, NC (United States)
Highlights: • Two novel small molecule inhibitors of MEKK2 discovered from screening. • Structures validated and activities confirmed in multiple MEKK2 biochemical assays. • Synthesis of analogs for iminocoumarin scaffold led to ≥20-fold more potent analogs. • Kinase profiling indicated that scaffold modifications could increase selectivity. • One analog inhibited ERK5 pathway activation in cells and cell migration. The kinase MEKK2 (MAP3K2) activates the MEK5/ERK5 cell signaling pathway and may play an important role in tumor growth and metastasis. Thus, MEKK2 may represent a novel kinase target for cancer. In order to identify inhibitors of MEKK2, we screened a library of compounds using a high throughput MEKK2 intrinsic ATPase enzyme assay. We identified two hits with validated structures and confirmed activity in the primary assay (IC{sub 50} values = 322 nM and 7.7 μM) and two orthogonal MEKK2 biochemical assays. Compound 1, the more potent hit, was the subject of further investigation. Limited structure-activity relationship (SAR) studies were performed on this iminocoumarin hit which resulted in ≥20-fold more potent analogs (e.g. 8 and 16 nM IC{sub 50}). Two analogs had improved selectivity in a 50-member kinase profiling panel compared to the hit. These studies suggested that substitutions around the phenoxy ring of this scaffold can impart improved potency and selectivity for MEKK2. Analog Compound 1s (16 nM IC{sub 50}) was further verified by external testing to inhibit MEKK2 and MEKK3 with similar potencies. Compound 1s displayed activity in cell-based assays in which it inhibited ERK5 pathway activation in cells and inhibited cell migration in a scratch assay. Thus, we have identified a scaffold that has promising potential to be developed into a highly selective and potent inhibitor of MEKK2. Information from these SAR studies provides specific guidance for the future design of MEKK2 inhibitor probes.
- OSTI ID:
- 23127433
- Journal Information:
- Biochemical and Biophysical Research Communications, Journal Name: Biochemical and Biophysical Research Communications Journal Issue: 1 Vol. 496; ISSN BBRCA9; ISSN 0006-291X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Discovery and Characterization of 2-Acylaminoimidazole Microsomal Prostaglandin E Synthase-1 Inhibitors
Fragment-Based and Structure-Guided Discovery and Optimization of Rho Kinase Inhibitors