Triazole Bridged Flavonoid Dimers as Potent, Nontoxic, and Highly Selective Breast Cancer Resistance Protein (BCRP/ABCG2) Inhibitors

J Med Chem. 2019 Sep 26;62(18):8578-8608. doi: 10.1021/acs.jmedchem.9b00963. Epub 2019 Sep 12.

Abstract

The present work describes the syntheses of diverse triazole bridged flavonoid dimers and identifies potent, nontoxic, and highly selective BCRP inhibitors. A homodimer, Ac22(Az8)2, with m-methoxycarbonylbenzyloxy substitution at C-3 of the flavone moieties and a bis-triazole-containing linker (21 atoms between the two flavones) showed low toxicity (IC50 toward L929, 3T3, and HFF-1 > 100 μM), potent BCRP-inhibitory activity (EC50 = 1-2 nM), and high BCRP selectivity (BCRP selectivity over MRP1 and P-gp > 455-909). Ac22(Az8)2 inhibits BCRP-ATPase activity, blocks the drug efflux activity of BCRP, elevates the intracellular drug accumulation, and finally restores the drug sensitivity of BCRP-overexpressing cells. It does not down-regulate the surface BCRP protein expression to enhance the drug retention. Therefore, Ac22(Az8)2 and similar flavonoid dimers appear to be promising candidates for further development into combination therapy to overcome MDR cancers with BCRP overexpression.

MeSH terms

  • 3T3 Cells
  • ATP Binding Cassette Transporter, Subfamily B, Member 1 / chemistry
  • ATP Binding Cassette Transporter, Subfamily G, Member 2 / antagonists & inhibitors*
  • Animals
  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / pharmacology*
  • Computer Simulation
  • Copper / chemistry
  • Dimerization
  • Drug Design
  • Drug Resistance, Multiple / drug effects
  • Drug Resistance, Neoplasm / drug effects
  • Flavones / chemistry
  • Flavonoids / chemistry
  • Flavonoids / pharmacology*
  • HEK293 Cells
  • Humans
  • Mice
  • Multidrug Resistance-Associated Proteins / antagonists & inhibitors
  • Multidrug Resistance-Associated Proteins / chemistry
  • Neoplasm Proteins / antagonists & inhibitors*
  • Triazoles / chemistry*

Substances

  • ABCG2 protein, human
  • ATP Binding Cassette Transporter, Subfamily B, Member 1
  • ATP Binding Cassette Transporter, Subfamily G, Member 2
  • Abcg2 protein, mouse
  • Antineoplastic Agents
  • Flavones
  • Flavonoids
  • Multidrug Resistance-Associated Proteins
  • Neoplasm Proteins
  • Triazoles
  • Copper
  • multidrug resistance-associated protein 1