Effective Virtual Screening Strategy toward heme-containing proteins: Identification of novel IDO1 inhibitors

  • Eur J Med Chem. 2019 Dec 15:184:111750. doi: 10.1016/j.ejmech.2019.111750.
Yi Zou  1 Yue Hu  2 Shushan Ge  3 Yingbo Zheng  3 Yuezhen Li  4 Wen Liu  2 Wenjie Guo  5 Yihua Zhang  3 Qiang Xu  6 Yisheng Lai  7
Affiliations
  • 1. State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Center of Drug Discovery, China Pharmaceutical University, Nanjing, 210009, PR China; CAS Key Laboratory of Receptor Research, Drug Discovery and Design Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences (CAS), Shanghai, 201203, PR China.
  • 2. State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210093, PR China.
  • 3. State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Center of Drug Discovery, China Pharmaceutical University, Nanjing, 210009, PR China.
  • 4. Department of Organic Chemistry, School of Science, China Pharmaceutical University, Nanjing, 211198, PR China.
  • 5. State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210093, PR China. Electronic address: [email protected].
  • 6. State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210093, PR China. Electronic address: [email protected].
  • 7. State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Center of Drug Discovery, China Pharmaceutical University, Nanjing, 210009, PR China. Electronic address: [email protected].
Abstract

Developing small molecules occupying the heme-binding site using computational approaches remains a challenging task because it is difficult to characterize heme-ligand interaction in heme-containing protein. Indoleamine 2,3-dioxygenase 1 (IDO1) is an intracellular heme-containing dioxygenase which is associated with the immunosuppressive effects in Cancer. With IDO1 as an example, herein we report a combined virtual screening (VS) strategy including high-specificity heme-binding group (HmBG)-based pharmacophore screening and cascade molecular docking to identify novel IDO1 inhibitors. A total of four hit compounds were obtained and showed proper binding with the heme iron coordinating site. Further structural optimization led to a promising compound S18-3, which exerted potent anti-tumor efficacy in BALB/c mice bearing established CT26 tumors by activating the host's immune system. These results suggest that S18-3 merits further study to assess its potential for the intervention of Cancer. Furthermore, our study also unveils a novel in silico-based strategy for identifying potential regulators for hemeproteins within short timeframe.

Keywords
Cancer immunotherapy; Drug design; Heme; IDO1; Molecular dynamics simulation; T cell; Virtual screening.