Drug repurposing through Biophysical Insights: Focus on Indoleamine 2,3-Dioxygenase and Tryptophan 2,3-Dioxygenase

Priyanga Paranthaman1, Ramanathan Karuppasamy1, Shanthi Veerappapillai2

  • 1Department of Biotechnology, School of Bio Sciences and Technology, Vellore Institute of Technology, Vellore, Tamil Nadu, India.

PubMed

Insights

This study repurposed FDA-approved drugs to find new inhibitors for indoleamine 2,3-dioxygenase (IDO1) and tryptophan 2,3-dioxygenase (TDO), key in triple-negative breast cancer (TNBC) immunosuppression. Dapagliflozin (DB06292) emerged as a promising candidate for TNBC management.

Area of Science:

  • Biochemistry
  • Immunology
  • Oncology

Background:

  • The kynurenine pathway (KP) and its enzymes, indoleamine 2,3-dioxygenase (IDO1) and tryptophan 2,3-dioxygenase (TDO), are crucial in regulating the tumor microenvironment and immune suppression in cancers like triple-negative breast cancer (TNBC).
  • Existing dual inhibitors like navoximod have shown limited clinical success due to poor bioavailability and efficacy, highlighting the need for novel therapeutic strategies targeting IDO1 and TDO.

Purpose of the Study:

  • To identify novel, FDA-approved drugs that can serve as dual inhibitors of IDO1 and TDO for potential TNBC treatment.
  • To repurpose existing drugs to overcome the limitations of current therapeutic approaches targeting the kynurenine pathway.

Main Methods:

  • Screening of 2588 FDA-approved compounds using molecular docking and pharmacokinetic profiling.
  • Utilizing MM-GBSA calculations and machine learning for lead compound identification, followed by toxicity and anticancer activity assessments.
  • Employing the PaccMann server for anticancer activity evaluation and molecular dynamics simulations to confirm binding stability of lead candidates.

Main Results:

  • Identification of 20 potential lead compounds with significant anticancer activity against MDA-MB-231 TNBC cell lines, with sensitivities ranging from 0.203 to 24.119 μM.
  • Dapagliflozin (DB06292) was identified as a highly promising hit candidate based on its interaction profile with critical residues and validated through molecular dynamics simulations.
  • The 200 ns molecular dynamics simulation confirmed the stable binding of Dapagliflozin to target proteins, reinforcing its potential as a therapeutic agent.

Conclusions:

  • Repurposing FDA-approved drugs is a viable strategy for discovering novel IDO1/TDO inhibitors.
  • Dapagliflozin demonstrates significant potential as a dual IDO1/TDO inhibitor for the management of triple-negative breast cancer.
  • Further investigation into Dapagliflozin's efficacy and safety is warranted for its clinical application in TNBC treatment.