Computational Discovery and Experimental Validation of Inhibitors of the Human Intestinal Transporter OATP2B1

J Chem Inf Model. 2017 Jun 26;57(6):1402-1413. doi: 10.1021/acs.jcim.6b00720. Epub 2017 Jun 15.

Abstract

Human organic anion transporters (OATPs) are vital for the uptake and efflux of drugs and endogenous compounds. Current identification of inhibitors of these transporters is based on experimental screening. Virtual screening remains a challenge due to a lack of experimental three-dimensional protein structures. Here, we describe a workflow to identify inhibitors of the OATP2B1 transporter in the DrugBank library of over 5,000 drugs and druglike molecules. OATP member 2B1 transporter is highly expressed in the intestine, where it participates in oral absorption of drugs. Predictions from a Random forest classifier, prioritized by docking against multiple comparative protein structure models of OATP2B1, indicated that 33 of the 5,000 compounds were putative inhibitors of OATP2B1. Ten predicted inhibitors that are prescription drugs were tested experimentally in cells overexpressing the OATP2B1 transporter. Three of these ten were validated as potent inhibitors of estrone-3-sulfate uptake (defined as more than 50% inhibition at 20 μM) and tested in multiple concentrations to determine exact IC50. The IC50 values of bicalutamide, ticagrelor, and meloxicam suggest that they might inhibit intestinal OATP2B1 at clinically relevant concentrations and therefore modulate the absorption of other concomitantly administered drugs.

Publication types

  • Validation Study

MeSH terms

  • Animals
  • CHO Cells
  • Computer Simulation
  • Cricetinae
  • Cricetulus
  • Drug Discovery / methods*
  • Drug Evaluation, Preclinical
  • Humans
  • Inhibitory Concentration 50
  • Molecular Docking Simulation
  • Organic Anion Transporters / antagonists & inhibitors*
  • Organic Anion Transporters / chemistry
  • Organic Anion Transporters / metabolism
  • Protein Conformation

Substances

  • Organic Anion Transporters
  • SLCO2B1 protein, human