Rational Adaptation of L3MBTL1 Inhibitors to Create Small-Molecule Cbx7 Antagonists

ChemMedChem. 2019 Aug 6;14(15):1444-1456. doi: 10.1002/cmdc.201900021. Epub 2019 Jul 22.

Abstract

Chromobox homolog 7 (Cbx7) is an epigenetic modulator that is an important driver of multiple cancers. It is a methyl reader protein that operates by recognizing and binding to methylated lysine residues on specific partners. Herein we report our efforts to create low-molecular-weight inhibitors of Cbx7 by making rational structural adaptations to inhibitors of a different methyl reader protein, L3MBTL1, inhibitors that had previously been reported to be inactive against Cbx7. We evaluated each new inhibitor for Cbx7 inhibition by fluorescence polarization assay, and also confirmed the binding of selected inhibitors to Cbx7 by saturation-transfer difference NMR spectroscopy. This work identified multiple small-molecule inhibitors with modest (IC50 : 257-500 μm) potency.

Keywords: anticancer agents; bromodomains; chromatin; epigenetics; histones.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Enzyme Inhibitors / chemical synthesis*
  • Enzyme Inhibitors / metabolism
  • Humans
  • Lysine / chemistry*
  • Methylation
  • Models, Molecular
  • Molecular Structure
  • Niacinamide / chemical synthesis*
  • Polycomb Repressive Complex 1 / antagonists & inhibitors*
  • Protein Binding
  • Protein Conformation
  • Repressor Proteins / antagonists & inhibitors*
  • Structure-Activity Relationship
  • Sulfonamides / chemical synthesis*
  • Tumor Suppressor Proteins / antagonists & inhibitors*

Substances

  • CBX7 protein, human
  • Enzyme Inhibitors
  • L3MBTL1 protein, human
  • Repressor Proteins
  • Sulfonamides
  • Tumor Suppressor Proteins
  • Niacinamide
  • Polycomb Repressive Complex 1
  • Lysine