1
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Cernicchi G, Rampacci E, Massari S, Manfroni G, Barreca ML, Tabarrini O, Cecchetti V, Felicetti T, Di Luca M, Poma NV, Tavanti A, Passamonti F, Rindi L, Sabatini S. Discovery of 2-phenylquinazolines as potent Mycobacterium avium efflux pump inhibitors able to synergize with clarithromycin against clinical isolate. Arch Pharm (Weinheim) 2024:e2400296. [PMID: 38923553 DOI: 10.1002/ardp.202400296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Revised: 06/04/2024] [Accepted: 06/06/2024] [Indexed: 06/28/2024]
Abstract
Nontuberculous mycobacteria (NTM), which include the Mycobacterium avium complex, are classified as difficult-to-treat pathogens due to their ability to quickly develop drug resistance against the most common antibiotics used to treat NTM infections. The overexpression of efflux pumps (EPs) was demonstrated to be a key mechanism of clarithromycin (CLA) resistance in NTM. Therefore, in this work, 24 compounds from an in-house library, characterized by chemical diversity, were tested as potential NTM EP inhibitors (EPIs) against Mycobacterium smegmatis mc2 155 and M. avium clinical isolates. Based on the acquired results, 12 novel analogs of the best derivatives 1b and 7b were designed and synthesized to improve the NTM EP inhibition activity. Among the second set of compounds, 13b emerged as the most potent NTM EPI. At a concentration of 4 µg/mL, it reduced the CLA minimum inhibitory concentration by 16-fold against the clinical isolate M. avium 2373 overexpressing EPs as primary mechanism of CLA resistance.
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Affiliation(s)
- Giada Cernicchi
- Department Pharmaceutical Sciences, Università degli Studi di Perugia, Perugia, Italy
| | - Elisa Rampacci
- Department of Veterinary Medicine, University of Perugia, Perugia, Italy
| | - Serena Massari
- Department Pharmaceutical Sciences, Università degli Studi di Perugia, Perugia, Italy
| | - Giuseppe Manfroni
- Department Pharmaceutical Sciences, Università degli Studi di Perugia, Perugia, Italy
| | - Maria Letizia Barreca
- Department Pharmaceutical Sciences, Università degli Studi di Perugia, Perugia, Italy
| | - Oriana Tabarrini
- Department Pharmaceutical Sciences, Università degli Studi di Perugia, Perugia, Italy
| | - Violetta Cecchetti
- Department Pharmaceutical Sciences, Università degli Studi di Perugia, Perugia, Italy
| | - Tommaso Felicetti
- Department Pharmaceutical Sciences, Università degli Studi di Perugia, Perugia, Italy
| | | | | | | | | | - Laura Rindi
- Department of Translational Research and New Technologies in Medicine and Surgery, Università di Pisa, Pisa, Italy
| | - Stefano Sabatini
- Department Pharmaceutical Sciences, Università degli Studi di Perugia, Perugia, Italy
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2
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Hillebrand L, Liang XJ, Serafim RAM, Gehringer M. Emerging and Re-emerging Warheads for Targeted Covalent Inhibitors: An Update. J Med Chem 2024; 67:7668-7758. [PMID: 38711345 DOI: 10.1021/acs.jmedchem.3c01825] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Covalent inhibitors and other types of covalent modalities have seen a revival in the past two decades, with a variety of new targeted covalent drugs having been approved in recent years. A key feature of such molecules is an intrinsically reactive group, typically a weak electrophile, which enables the irreversible or reversible formation of a covalent bond with a specific amino acid of the target protein. This reactive group, often called the "warhead", is a critical determinant of the ligand's activity, selectivity, and general biological properties. In 2019, we summarized emerging and re-emerging warhead chemistries to target cysteine and other amino acids (Gehringer, M.; Laufer, S. A. J. Med. Chem. 2019, 62, 5673-5724; DOI: 10.1021/acs.jmedchem.8b01153). Since then, the field has rapidly evolved. Here we discuss the progress on covalent warheads made since our last Perspective and their application in medicinal chemistry and chemical biology.
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Affiliation(s)
- Laura Hillebrand
- Department of Pharmaceutical/Medicinal Chemistry, Eberhard Karls University Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany
| | - Xiaojun Julia Liang
- Department of Pharmaceutical/Medicinal Chemistry, Eberhard Karls University Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany
- Cluster of Excellence iFIT (EXC 2180) "Image-Guided & Functionally Instructed Tumor Therapies", University of Tübingen, 72076 Tübingen, Germany
| | - Ricardo A M Serafim
- Department of Pharmaceutical/Medicinal Chemistry, Eberhard Karls University Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany
| | - Matthias Gehringer
- Department of Pharmaceutical/Medicinal Chemistry, Eberhard Karls University Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany
- Cluster of Excellence iFIT (EXC 2180) "Image-Guided & Functionally Instructed Tumor Therapies", University of Tübingen, 72076 Tübingen, Germany
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3
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Yu YC, Tong ZJ, Liang XT, Wu JZ, Xu YJ, Wang JJ, Zhang MY, Wei TH, Yang J, Wang YB, Wang QX, Li QQ, Wang Z, Leng X, Ding N, Xue X, Sun SL, Li NG, Wang XL. Discovery of RORγ Allosteric Fluorescent Probes and Their Application: Fluorescence Polarization, Screening, and Bioimaging. J Med Chem 2024; 67:4194-4224. [PMID: 38442261 DOI: 10.1021/acs.jmedchem.4c00058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2024]
Abstract
Retinoic acid receptor-related orphan receptor γ (RORγ) acts as a crucial transcription factor in Th17 cells and is involved in diverse autoimmune disorders. RORγ allosteric inhibitors have gained significant research focus as a novel strategy to inhibit RORγ transcriptional activity. Leveraging the high affinity and selectivity of RORγ allosteric inhibitor MRL-871 (1), this study presents the design, synthesis, and characterization of 11 allosteric fluorescent probes. Utilizing the preferred probe 12h, we established an efficient and cost-effective fluorescence polarization-based affinity assay for screening RORγ allosteric binders. By employing virtual screening in conjunction with this assay, 10 novel RORγ allosteric inhibitors were identified. The initial SAR studies focusing on the hit compound G381-0087 are also presented. The encouraging outcomes indicate that probe 12h possesses the potential to function as a powerful tool in facilitating the exploration of RORγ allosteric inhibitors and furthering understanding of RORγ function.
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Affiliation(s)
- Yan-Cheng Yu
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
| | - Zhen-Jiang Tong
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
| | - Xiao-Ting Liang
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
| | - Jia-Zhen Wu
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
| | - Yu-Jing Xu
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
| | - Jing-Jing Wang
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
| | - Meng-Yuan Zhang
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
| | - Tian-Hua Wei
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
| | - Jin Yang
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
| | - Yi-Bo Wang
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
| | - Qing-Xin Wang
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
| | - Qing-Qing Li
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
| | - Zixuan Wang
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
| | - XueJiao Leng
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
| | - Ning Ding
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
| | - Xin Xue
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
| | - Shan-Liang Sun
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
| | - Nian-Guang Li
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
| | - Xiao-Long Wang
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, 138 Xianlin Avenue, Nanjing, Jiangsu 210023, China
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4
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Rajan S, Yoon HS. Covalent ligands of nuclear receptors. Eur J Med Chem 2023; 261:115869. [PMID: 37857142 DOI: 10.1016/j.ejmech.2023.115869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 10/09/2023] [Accepted: 10/09/2023] [Indexed: 10/21/2023]
Abstract
Nuclear receptors (NRs) are ligand-induced transcriptional factors implicated in several physiological pathways. Naïve ligands bind to their cognate receptors and modulate gene expression as agonists or antagonists. It has been observed that some ligands bind via covalent bonding with the NR Ligand Binding Domain (LBD) residues. While many such instances have been known since the 1980s, a consolidated account of these ligands and their interactions with NR-LBD is yet to be documented. To negate this, we have culled out the human NR-LBDs that form a covalent attachment with ligands. According to the study, 16 of the 48 human NRs have been targeted by covalent ligands. It was found that conserved cysteines prone to covalent attachment are predominantly located in NR-LBD helices 3 and 11. These conserved cysteines are also observed in many of the remaining NRs, which can be probed for their reactivity. Thus, the structural insights into NR-LBD interactions with covalent ligands presented here would aid drug discovery efforts targeting NRs.
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Affiliation(s)
- Sreekanth Rajan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore
| | - Ho Sup Yoon
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore; College of Pharmacy, CHA University, 120 Haeryong-ro, Pocheon-si, Gyeonggi-do, 11160, Republic of Korea; CHA Advanced Research Institute, 335 Pangyo-ro, Bundang-gu, Seongnam-si, 13488, Republic of Korea.
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5
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Bachorz RA, Pastwińska J, Nowak D, Karaś K, Karwaciak I, Ratajewski M. The application of machine learning methods to the prediction of novel ligands for ROR γ/ROR γT receptors. Comput Struct Biotechnol J 2023; 21:5491-5505. [PMID: 38022699 PMCID: PMC10663739 DOI: 10.1016/j.csbj.2023.10.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 10/11/2023] [Accepted: 10/11/2023] [Indexed: 12/01/2023] Open
Abstract
In this work, we developed and applied a computational procedure for creating and validating predictive models capable of estimating the biological activity of ligands. The combination of modern machine learning methods, experimental data, and the appropriate setup of molecular descriptors led to a set of well-performing models. We thoroughly inspected both the methodological space and various possibilities for creating a chemical feature space. The resulting models were applied to the virtual screening of the ZINC20 database to identify new, biologically active ligands of RORγ receptors, which are a subfamily of nuclear receptors. Based on the known ligands of RORγ, we selected candidates and calculate their predicted activities with the best-performing models. We chose two candidates that were experimentally verified. One of these candidates was confirmed to induce the biological activity of the RORγ receptors, which we consider proof of the efficacy of the proposed methodology.
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Affiliation(s)
- Rafał A. Bachorz
- Institute of Medical Biology, Polish Academy of Sciences, Lodowa 106, Łódź, 93-232, Poland
| | - Joanna Pastwińska
- Institute of Medical Biology, Polish Academy of Sciences, Lodowa 106, Łódź, 93-232, Poland
| | - Damian Nowak
- Institute of Medical Biology, Polish Academy of Sciences, Lodowa 106, Łódź, 93-232, Poland
| | - Kaja Karaś
- Institute of Medical Biology, Polish Academy of Sciences, Lodowa 106, Łódź, 93-232, Poland
| | - Iwona Karwaciak
- Institute of Medical Biology, Polish Academy of Sciences, Lodowa 106, Łódź, 93-232, Poland
| | - Marcin Ratajewski
- Institute of Medical Biology, Polish Academy of Sciences, Lodowa 106, Łódź, 93-232, Poland
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6
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Arifi S, Marschner JA, Pollinger J, Isigkeit L, Heitel P, Kaiser A, Obeser L, Höfner G, Proschak E, Knapp S, Chaikuad A, Heering J, Merk D. Targeting the Alternative Vitamin E Metabolite Binding Site Enables Noncanonical PPARγ Modulation. J Am Chem Soc 2023. [PMID: 37385602 DOI: 10.1021/jacs.3c03417] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/01/2023]
Abstract
The lipid-sensing transcription factor PPARγ is the target of antidiabetic thiazolidinediones (TZD). At two sites within its ligand binding domain, it also binds oxidized vitamin E metabolites and the vitamin E mimetic garcinoic acid. While the canonical interaction within the TZD binding site mediates classical PPARγ activation, the effects of the second binding on PPARγ activity remain elusive. Here, we identified an agonist mimicking dual binding of vitamin E metabolites and developed a selective ligand of the second site, unveiling potential noncanonical regulation of PPARγ activities. We found that this alternative binding event can simultaneously occur with orthosteric ligands and it exerted different effects on PPARγ-cofactor interactions compared to both orthosteric PPARγ agonists and antagonists, indicating the diverse roles of the two binding sites. Alternative site binding lacked the pro-adipogenic effect of TZD and mediated no classical PPAR signaling in differential gene expression analysis but markedly diminished FOXO signaling, suggesting potential therapeutic applications.
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Affiliation(s)
- Silvia Arifi
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, D-60438 Frankfurt, Germany
| | - Julian A Marschner
- Department of Pharmacy, Ludwig-Maximilians-Universität München, D-81377 Munich, Germany
| | - Julius Pollinger
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, D-60438 Frankfurt, Germany
| | - Laura Isigkeit
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, D-60438 Frankfurt, Germany
| | - Pascal Heitel
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, D-60438 Frankfurt, Germany
| | - Astrid Kaiser
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, D-60438 Frankfurt, Germany
| | - Lennart Obeser
- Department of Pharmacy, Ludwig-Maximilians-Universität München, D-81377 Munich, Germany
| | - Georg Höfner
- Department of Pharmacy, Ludwig-Maximilians-Universität München, D-81377 Munich, Germany
| | - Ewgenij Proschak
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, D-60438 Frankfurt, Germany
- Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, D-60596 Frankfurt, Germany
| | - Stefan Knapp
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, D-60438 Frankfurt, Germany
- Structural Genomics Consortium, BMLS, Goethe University Frankfurt, D-60438 Frankfurt, Germany
| | - Apirat Chaikuad
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, D-60438 Frankfurt, Germany
- Structural Genomics Consortium, BMLS, Goethe University Frankfurt, D-60438 Frankfurt, Germany
| | - Jan Heering
- Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, D-60596 Frankfurt, Germany
| | - Daniel Merk
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, D-60438 Frankfurt, Germany
- Department of Pharmacy, Ludwig-Maximilians-Universität München, D-81377 Munich, Germany
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7
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Zhang J, Chen B, Zhang C, Sun N, Huang X, Wang W, Fu W. Modes of action insights from the crystallographic structures of retinoic acid receptor-related orphan receptor-γt (RORγt). Eur J Med Chem 2023; 247:115039. [PMID: 36566711 DOI: 10.1016/j.ejmech.2022.115039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 11/29/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022]
Abstract
RORγt plays an important role in mediating IL-17 production and some tumor cells. It has four functional domains, of which the ligand-binding domain (LBD) is responsible for binding agonists to recruit co-activators or inverse agonists to prevent co-activator recruiting the agonists. Thus, potent ligands targeting the LBD of this protein could provide novel treatments for cancer and autoimmune diseases. In this perspective, we summarized and discussed various modes of action (MOA) of RORγt-ligand binding structures. The ligands can bind with RORγt at either orthosteric site or the allosteric site, and the binding modes at these two sites are different for agonists and inverse agonist. At the orthosteric site, the binding of agonist is to stabilize the H479-Y502-F506 triplet interaction network of RORγt. The binding of inverse agonist features as these four apparent ways: (1) blocking the entrance of the agonist pocket in RORγt; (2) directly breaking the H479-Y502 pair interactions; (3) destabilizing the triplet H479-Y502-F506 interaction network through perturbing the conformation of the side chain in M358 at the bottom of the binding pocket; (4) and destabilizing the triplet H479-Y502-F506 through changing the conformation of the side chain of residue W317 side chain. At the allosteric site of RORγt, the binding of inverse agonist was found recently to inhibit the activation of protein by interacting directly with H12, which results in unfolding of helix 11' and orientation of H12 to directly block cofactor peptide binding. This overview of recent advances in the RORγt structures is expected to provide a guidance of designing more potent drugs to treat RORγt-related diseases.
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Affiliation(s)
- Junjie Zhang
- School of Pharmacy & Minhang Hospital, Fudan University, Shanghai, 201301, PR China
| | - Baiyu Chen
- School of Pharmacy & Minhang Hospital, Fudan University, Shanghai, 201301, PR China
| | - Chao Zhang
- School of Pharmacy & Minhang Hospital, Fudan University, Shanghai, 201301, PR China
| | - Nannan Sun
- School of Pharmacy & Minhang Hospital, Fudan University, Shanghai, 201301, PR China
| | - Xiaoqin Huang
- Center for Research Computing, Office of Information Technology, Center for Theoretical Biological Physics, Rice University, Houston, TX, 77030, USA
| | - Wuqing Wang
- School of Pharmacy & Minhang Hospital, Fudan University, Shanghai, 201301, PR China
| | - Wei Fu
- School of Pharmacy & Minhang Hospital, Fudan University, Shanghai, 201301, PR China.
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8
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Nussinov R, Zhang M, Maloney R, Liu Y, Tsai CJ, Jang H. Allostery: Allosteric Cancer Drivers and Innovative Allosteric Drugs. J Mol Biol 2022; 434:167569. [PMID: 35378118 PMCID: PMC9398924 DOI: 10.1016/j.jmb.2022.167569] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 03/11/2022] [Accepted: 03/25/2022] [Indexed: 01/12/2023]
Abstract
Here, we discuss the principles of allosteric activating mutations, propagation downstream of the signals that they prompt, and allosteric drugs, with examples from the Ras signaling network. We focus on Abl kinase where mutations shift the landscape toward the active, imatinib binding-incompetent conformation, likely resulting in the high affinity ATP outcompeting drug binding. Recent pharmacological innovation extends to allosteric inhibitor (GNF-5)-linked PROTAC, targeting Bcr-Abl1 myristoylation site, and broadly, allosteric heterobifunctional degraders that destroy targets, rather than inhibiting them. Designed chemical linkers in bifunctional degraders can connect the allosteric ligand that binds the target protein and the E3 ubiquitin ligase warhead anchor. The physical properties and favored conformational state of the engineered linker can precisely coordinate the distance and orientation between the target and the recruited E3. Allosteric PROTACs, noncompetitive molecular glues, and bitopic ligands, with covalent links of allosteric ligands and orthosteric warheads, increase the effective local concentration of productively oriented and placed ligands. Through covalent chemical or peptide linkers, allosteric drugs can collaborate with competitive drugs, degrader anchors, or other molecules of choice, driving innovative drug discovery.
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Affiliation(s)
- Ruth Nussinov
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism, National Cancer Institute, Frederick, MD 21702, USA; Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel.
| | - Mingzhen Zhang
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism, National Cancer Institute, Frederick, MD 21702, USA
| | - Ryan Maloney
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism, National Cancer Institute, Frederick, MD 21702, USA
| | - Yonglan Liu
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism, National Cancer Institute, Frederick, MD 21702, USA
| | - Chung-Jung Tsai
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism, National Cancer Institute, Frederick, MD 21702, USA
| | - Hyunbum Jang
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism, National Cancer Institute, Frederick, MD 21702, USA
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Abstract
INTRODUCTION Undruggable targets refer to clinically meaningful therapeutic targets that are 'difficult to drug' or 'yet to be drugged' via traditional approaches. Featuring characteristics of lacking defined ligand-binding pockets, non-catalytic protein-protein interaction functional modes and less-investigated 3D structures, these undruggable targets have been targeted with novel therapeutic entities developed with the progress of unconventional drug discovery approaches, such as targeted degradation molecules and display technologies. AREA COVERED This review first presents the concept of 'undruggable' exemplified by RAS and other targets. Next, detailed strategies are illustrated in two aspects: innovation of therapeutic entities and development of unconventional drug discovery technologies. Finally, case studies covering typical undruggable targets (Bcl-2, p53, and RAS) are depicted to further demonstrate the feasibility of the strategies and entities above. EXPERT OPINION Targeting the undruggable expands the scope of therapeutically reachable targets. Consequently, it represents the drug discovery frontier. Biomedical studies are capable of dissecting disease mechanisms, thus broadening the list of undruggable targets. Encouraged by the recent approval of the KRAS inhibitor Sotorasib, we believe that merging multiple discovery approaches and exploiting various novel therapeutic entities would pave the way for dealing with more 'undruggable' targets in the future.
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Affiliation(s)
- Gong Zhang
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing, P. R. China
| | - Juan Zhang
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing, P. R. China
| | - Yuting Gao
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing, P. R. China
| | - Yangfeng Li
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing, P. R. China
| | - Yizhou Li
- Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing, P. R. China.,Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, China
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