1. Discovering New Metallo-Deubiquitinase CSN5 Inhibitors by a Non-Catalytic Activity Assay Platform.
- Author
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Yan YH, Wei LL, Wu JW, Wei SQ, Jiang YY, Yu JL, Yang LL, and Li GB
- Subjects
- Humans, Enzyme Inhibitors pharmacology, Enzyme Inhibitors chemistry, B7-H1 Antigen antagonists & inhibitors, B7-H1 Antigen metabolism, Molecular Dynamics Simulation, Fluorescent Dyes chemistry, HCT116 Cells, Antineoplastic Agents pharmacology, Antineoplastic Agents chemistry, Drug Discovery methods, Structure-Activity Relationship, Peptide Hydrolases, Intracellular Signaling Peptides and Proteins, COP9 Signalosome Complex metabolism, COP9 Signalosome Complex antagonists & inhibitors
- Abstract
COP9 signalosome catalytic subunit CSN5 plays a key role in tumorigenesis and tumor immunity, showing potential as an anticancer target. Currently, only a few CSN5 inhibitors have been reported, at least partially, due to the challenges in establishing assays for CSN5 deubiquitinase activity. Here, we present the establishment and validation of a simple and reliable non-catalytic activity assay platform for identifying CSN5 inhibitors utilizing a new fluorescent probe, CFP-1 , that exhibits enhanced fluorescence and fluorescence polarization features upon binding to CSN5. By using this platform, we identified 2-aminothiazole-4-carboxylic acids as new CSN5 inhibitors, which inhibited CSN5 but slightly downregulated PD-L1 in cancer cells. Furthermore, through the integration of deep learning-enabled virtual screening, we discovered that shikonins are nanomolar CSN5 inhibitors, which can upregulate PD-L1 in HCT116 cells. The binding modes of these structurally distinct inhibitors with CSN5 were explored by using microsecond-scale molecular dynamics simulations and tryptophan quenching assays.
- Published
- 2024
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