title: Molecular docking and dynamic simulation studies evidenced plausible immunotherapeutic anticancer property by Withaferin A targeting indoleamine 2,3-dioxygenase.
abstract: Indoleamine 2,3-dioxygenase (IDO) is emerging as an important new therapeutic drug target for the treatment of cancer characterized by pathological immune suppression. IDO catalyzes the rate-limiting step of tryptophan degradation along the kynurenine pathway. Reduction in local tryptophan concentration and the production of immunomodulatory tryptophan metabolites contribute to the immunosuppressive effects of IDO. Presence of IDO on dentritic cells in tumor-draining lymph nodes leading to the activation of T cells toward forming immunosuppressive microenvironment for the survival of tumor cells has confirmed the importance of IDO as a promising novel anticancer immunotherapy drug target. On the other hand, Withaferin A (WA) - active constituent of Withania Somnifera ayurvedic herb has shown to be having a wide range of targeted anticancer properties. In the present study conducted here is an attempt to explore the potential of WA in attenuating IDO for immunotherapeutic tumor arresting activity and to elucidate the underlying mode of action in a computational approach. Our docking and molecular dynamic simulation results predict high binding affinity of the ligand to the receptor with up to -11.51 kcal/mol of energy and 3.63 nM of IC50 value. Further, de novo molecular dynamic simulations predicted stable ligand interactions with critically important residues SER167; ARG231; LYS377, and heme moiety involved in IDO's activity. Conclusively, our results strongly suggest WA as a valuable small ligand molecule with strong binding affinity toward IDO.
authors: a Department of CSE , JNTU Kakinada , Kakinada , Andhra Pradesh 533 003 , India.|b Department of CSE , GIT, GITAM University , Visakhapatnam , Andhra Pradesh 530 045 , India.
authors: S V G
authors: SV
authors: Reddy
authors: b Department of CSE , GIT, GITAM University , Visakhapatnam , Andhra Pradesh 530 045 , India.
authors: K Thammi
authors: KT
authors: Reddy
authors: c Department of CSE , Andhra University , Visakhapatnam , Andhra Pradesh 530 003 , India.
authors: V Valli
authors: VV
authors: Kumari
authors: d Innovative Informatica Technologies , Hyderabad 500049 , India.
authors: Syed Hussain
authors: SH
authors: Basha
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000378:metabolism / Q000627:therapeutic use; D001665:Binding Sites; D001667:Binding, Competitive; D006801:Humans; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000378:metabolism; D007700:Kinetics; D008024:Ligands; D062105:Molecular Docking Simulation; D056004:Molecular Dynamics Simulation; D015394:Molecular Structure; D009369:Neoplasms / Q000188:drug therapy / Q000201:enzymology / Q000378:metabolism; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D014364:Tryptophan / Q000378:metabolism; D014867:Water / Q000737:chemistry; D032341:Withania / Q000737:chemistry; D054358:Withanolides / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology
chemical_list: D000970:Antineoplastic Agents; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase; D008024:Ligands; D054358:Withanolides; D014867:Water; D014364:Tryptophan; C009684:withaferin A
keywords: 2,3-dioxygenase; Indoleamine; Withaferin A; anticancer immunotherapy; docking; molecular dynamic simulations