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Shao M, Pan Q, Tan H, Wu J, Lee HW, Huber AD, Wright WC, Cho JH, Yu J, Peng J, Chen T. CYP3A5 unexpectedly regulates glucose metabolism through the AKT-TXNIP-GLUT1 axis in pancreatic cancer. Genes Dis 2024; 11:101079. [PMID: 38560501 PMCID: PMC10980945 DOI: 10.1016/j.gendis.2023.101079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 07/19/2023] [Indexed: 04/04/2024] Open
Abstract
CYP3A5 is a cytochrome P450 (CYP) enzyme that metabolizes drugs and contributes to drug resistance in cancer. However, it remains unclear whether CYP3A5 directly influences cancer progression. In this report, we demonstrate that CYP3A5 regulates glucose metabolism in pancreatic ductal adenocarcinoma. Multi-omics analysis showed that CYP3A5 knockdown results in a decrease in various glucose-related metabolites through its effect on glucose transport. A mechanistic study revealed that CYP3A5 enriches the glucose transporter GLUT1 at the plasma membrane by restricting the translation of TXNIP, a negative regulator of GLUT1. Notably, CYP3A5-generated reactive oxygen species were proved to be responsible for attenuating the AKT-4EBP1-TXNIP signaling pathway. CYP3A5 contributes to cell migration by maintaining high glucose uptake in pancreatic cancer. Taken together, our results, for the first time, reveal a role of CYP3A5 in glucose metabolism in pancreatic ductal adenocarcinoma and identify a novel mechanism that is a potential therapeutic target.
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Affiliation(s)
- Ming Shao
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Qingfei Pan
- Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Haiyan Tan
- Center for Proteomics and Metabolomics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Jing Wu
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Ha Won Lee
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Andrew D. Huber
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - William C. Wright
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Ji-Hoon Cho
- Center for Proteomics and Metabolomics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Jiyang Yu
- Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Junmin Peng
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Taosheng Chen
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
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2
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Huber AD, Poudel S, Wu J, Miller DJ, Lin W, Yang L, Bwayi MN, Rimmer MA, Gee RRF, Seetharaman J, Chai SC, Chen T. A bromodomain-independent mechanism of gene regulation by the BET inhibitor JQ1: direct activation of nuclear receptor PXR. Nucleic Acids Res 2024; 52:1661-1676. [PMID: 38084912 PMCID: PMC10899790 DOI: 10.1093/nar/gkad1175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 11/17/2023] [Accepted: 11/23/2023] [Indexed: 02/29/2024] Open
Abstract
Bromodomain and extraterminal (BET) proteins are extensively studied in multiple pathologies, including cancer. BET proteins modulate transcription of various genes, including those synonymous with cancer, such as MYC. Thus, BET inhibitors are a major area of drug development efforts. (+)-JQ1 (JQ1) is the prototype inhibitor and is a common tool to probe BET functions. While showing therapeutic promise, JQ1 is not clinically usable, partly due to metabolic instability. Here, we show that JQ1 and the BET-inactive (-)-JQ1 are agonists of pregnane X receptor (PXR), a nuclear receptor that transcriptionally regulates genes encoding drug-metabolizing enzymes such as CYP3A4, which was previously shown to oxidize JQ1. A PXR-JQ1 co-crystal structure identified JQ1's tert-butyl moiety as a PXR anchor and explains binding by (-)-JQ1. Analogs differing at the tert-butyl lost PXR binding, validating our structural findings. Evaluation in liver cell models revealed both PXR-dependent and PXR-independent modulation of CYP3A4 expression by BET inhibitors. We have characterized a non-BET JQ1 target, a mechanism of physiological JQ1 instability, a biological function of (-)-JQ1, and BET-dependent transcriptional regulation of drug metabolism genes.
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Affiliation(s)
- Andrew D Huber
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
| | - Shyaron Poudel
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
| | - Jing Wu
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
| | - Darcie J Miller
- Department of Structural Biology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
| | - Wenwei Lin
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
| | - Lei Yang
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
| | - Monicah N Bwayi
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
| | - Mary Ashley Rimmer
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
| | - Rebecca R Florke Gee
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
- Graduate School of Biomedical Sciences, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
| | - Jayaraman Seetharaman
- Department of Structural Biology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
| | - Sergio C Chai
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
| | - Taosheng Chen
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
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3
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Florke Gee RR, Huber AD, Chen T. Regulation of PXR in drug metabolism: chemical and structural perspectives. Expert Opin Drug Metab Toxicol 2024; 20:9-23. [PMID: 38251638 PMCID: PMC10939797 DOI: 10.1080/17425255.2024.2309212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 01/19/2024] [Indexed: 01/23/2024]
Abstract
INTRODUCTION Pregnane X receptor (PXR) is a master xenobiotic sensor that transcriptionally controls drug metabolism and disposition pathways. PXR activation by pharmaceutical drugs, natural products, environmental toxins, etc. may decrease drug efficacy and increase drug-drug interactions and drug toxicity, indicating a therapeutic value for PXR antagonists. However, PXR's functions in physiological events, such as intestinal inflammation, indicate that PXR activators may be useful in certain disease contexts. AREAS COVERED We review the reported roles of PXR in various physiological and pathological processes including drug metabolism, cancer, inflammation, energy metabolism, and endobiotic homeostasis. We then highlight specific cellular and chemical routes that modulate PXR activity and discuss the functional consequences. Databases searched and inclusive dates: PubMed, 1 January 1980 to 10 January 2024. EXPERT OPINION Knowledge of PXR's drug metabolism function has helped drug developers produce small molecules without PXR-mediated metabolic liabilities, and further understanding of PXR's cellular functions may offer drug development opportunities in multiple disease settings.
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Affiliation(s)
- Rebecca R. Florke Gee
- Graduate School of Biomedical Sciences, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA
- Department of Chemical Biology and Therapeutics, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA
| | - Andrew D. Huber
- Department of Chemical Biology and Therapeutics, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA
| | - Taosheng Chen
- Department of Chemical Biology and Therapeutics, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA
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4
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Huber AD, Poudel S, Li Y, Lin W, Wu J, Miller DJ, Chen T. Ligand flexibility and binding pocket malleability cooperate to allow selective PXR activation by analogs of a promiscuous nuclear receptor ligand. Structure 2023; 31:1545-1555.e9. [PMID: 37729916 PMCID: PMC10872772 DOI: 10.1016/j.str.2023.08.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 08/01/2023] [Accepted: 08/23/2023] [Indexed: 09/22/2023]
Abstract
The human nuclear receptor (NR) family of transcription factors contains 48 proteins that bind lipophilic molecules. Approved NR therapies have had immense success treating various diseases, but lack of selectivity has hindered efforts to therapeutically target the majority of NRs due to unpredictable off-target effects. The synthetic ligand T0901317 was originally discovered as a potent agonist of liver X receptors (LXRα/β) but subsequently found to target additional NRs, with activation of pregnane X receptor (PXR) being as potent as that of LXRs. We previously showed that directed rigidity reduces PXR binding by T0901317 derivatives through unfavorable protein remodeling. Here, we use a similar approach to achieve selectivity for PXR over other T0901317-targeted NRs. One molecule, SJPYT-318, accomplishes selectivity by favorably utilizing PXR's flexible binding pocket and surprisingly binding in a new mode distinct from the parental T0901317. Our work provides a structure-guided framework to achieve NR selectivity from promiscuous compounds.
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Affiliation(s)
- Andrew D Huber
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Shyaron Poudel
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Yongtao Li
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Wenwei Lin
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Jing Wu
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Darcie J Miller
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Taosheng Chen
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
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5
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Florke Gee RR, Huber AD, Wu J, Bajpai R, Loughran AJ, Pruett-Miller SM, Chen T. The F-box-only protein 44 regulates pregnane X receptor protein level by ubiquitination and degradation. Acta Pharm Sin B 2023; 13:4523-4534. [PMID: 37969738 PMCID: PMC10638512 DOI: 10.1016/j.apsb.2023.07.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 05/24/2023] [Accepted: 06/13/2023] [Indexed: 11/17/2023] Open
Abstract
Pregnane X receptor (PXR) is a ligand-activated nuclear receptor that transcriptionally upregulates drug-metabolizing enzymes [e.g., cytochrome P450 3A4 (CYP3A4)] and transporters. Although the regulation of PXR target genes is well-characterized, less is known about the regulation of PXR protein level. By screening an RNAi library, we identified the F-box-only protein 44 (FBXO44) as a novel E3 ligase for PXR. PXR abundance increases upon knockdown of FBXO44, and, inversely, decreases upon overexpression of FBXO44. Further analysis revealed that FBXO44 interacts with PXR, leading to its ubiquitination and proteasomal degradation, and we determined that the F-box associated domain of FBXO44 and the ligand binding domain of PXR are required for the functional interaction. In summary, FBXO44 regulates PXR protein abundance, which has downstream consequences for CYP3A4 levels and drug-drug interactions. The results of this study provide new insight into the molecular mechanisms that regulate PXR protein level and activity and suggest the importance of considering how modulating E3 ubiquitin ligase activities will affect PXR-mediated drug metabolism.
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Affiliation(s)
- Rebecca R. Florke Gee
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
- Graduate School of Biomedical Sciences, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Andrew D. Huber
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Jing Wu
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Richa Bajpai
- Center for Advanced Genome Engineering and Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Allister J. Loughran
- Center for Advanced Genome Engineering and Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Shondra M. Pruett-Miller
- Center for Advanced Genome Engineering and Department of Cell and Molecular Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Taosheng Chen
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
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6
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Liu D, Ndongwe TP, Ji J, Huber AD, Michailidis E, Rice CM, Ralston R, Tedbury PR, Sarafianos SG. Mechanisms of Action of the Host-Targeting Agent Cyclosporin A and Direct-Acting Antiviral Agents against Hepatitis C Virus. Viruses 2023; 15:v15040981. [PMID: 37112961 PMCID: PMC10143304 DOI: 10.3390/v15040981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 03/30/2023] [Accepted: 04/04/2023] [Indexed: 04/29/2023] Open
Abstract
Several direct-acting antivirals (DAAs) are available, providing interferon-free strategies for a hepatitis C cure. In contrast to DAAs, host-targeting agents (HTAs) interfere with host cellular factors that are essential in the viral replication cycle; as host genes, they are less likely to rapidly mutate under drug pressure, thus potentially exhibiting a high barrier to resistance, in addition to distinct mechanisms of action. We compared the effects of cyclosporin A (CsA), a HTA that targets cyclophilin A (CypA), to DAAs, including inhibitors of nonstructural protein 5A (NS5A), NS3/4A, and NS5B, in Huh7.5.1 cells. Our data show that CsA suppressed HCV infection as rapidly as the fastest-acting DAAs. CsA and inhibitors of NS5A and NS3/4A, but not of NS5B, suppressed the production and release of infectious HCV particles. Intriguingly, while CsA rapidly suppressed infectious extracellular virus levels, it had no significant effect on the intracellular infectious virus, suggesting that, unlike the DAAs tested here, it may block a post-assembly step in the viral replication cycle. Hence, our findings shed light on the biological processes involved in HCV replication and the role of CypA.
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Affiliation(s)
- Dandan Liu
- CS Bond Life Sciences Center, Department of Molecular Microbiology & Immunology, University of Missouri, Columbia, MO 65201, USA
| | - Tanya P Ndongwe
- CS Bond Life Sciences Center, Department of Molecular Microbiology & Immunology, University of Missouri, Columbia, MO 65201, USA
| | - Juan Ji
- CS Bond Life Sciences Center, Department of Molecular Microbiology & Immunology, University of Missouri, Columbia, MO 65201, USA
| | - Andrew D Huber
- CS Bond Life Sciences Center, Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65201, USA
| | - Eleftherios Michailidis
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA
- Laboratory of Biochemical Pharmacology, Center for ViroScience and Cure, Department of Pediatrics, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA 30322, USA
| | - Charles M Rice
- Laboratory of Virology and Infectious Disease, The Rockefeller University, New York, NY 10065, USA
| | - Robert Ralston
- CS Bond Life Sciences Center, Department of Molecular Microbiology & Immunology, University of Missouri, Columbia, MO 65201, USA
| | - Philip R Tedbury
- CS Bond Life Sciences Center, Department of Molecular Microbiology & Immunology, University of Missouri, Columbia, MO 65201, USA
- Laboratory of Biochemical Pharmacology, Center for ViroScience and Cure, Department of Pediatrics, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA 30322, USA
| | - Stefan G Sarafianos
- CS Bond Life Sciences Center, Department of Molecular Microbiology & Immunology, University of Missouri, Columbia, MO 65201, USA
- Laboratory of Biochemical Pharmacology, Center for ViroScience and Cure, Department of Pediatrics, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, GA 30322, USA
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7
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Lin W, Huber AD, Poudel S, Li Y, Seetharaman J, Miller DJ, Chen T. Structure-guided approach to modulate small molecule binding to a promiscuous ligand-activated protein. Proc Natl Acad Sci U S A 2023; 120:e2217804120. [PMID: 36848571 PMCID: PMC10013835 DOI: 10.1073/pnas.2217804120] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 01/30/2023] [Indexed: 03/01/2023] Open
Abstract
Ligand-binding promiscuity in detoxification systems protects the body from toxicological harm but is a roadblock to drug development due to the difficulty in optimizing small molecules to both retain target potency and avoid metabolic events. Immense effort is invested in evaluating metabolism of molecules to develop safer, more effective treatments, but engineering specificity into or out of promiscuous proteins and their ligands is a challenging task. To better understand the promiscuous nature of detoxification networks, we have used X-ray crystallography to characterize a structural feature of pregnane X receptor (PXR), a nuclear receptor that is activated by diverse molecules (with different structures and sizes) to up-regulate transcription of drug metabolism genes. We found that large ligands expand PXR's ligand-binding pocket, and the ligand-induced expansion occurs through a specific unfavorable compound-protein clash that likely contributes to reduced binding affinity. Removing the clash by compound modification resulted in more favorable binding modes with significantly enhanced binding affinity. We then engineered the unfavorable ligand-protein clash into a potent, small PXR ligand, resulting in marked reduction in PXR binding and activation. Structural analysis showed that PXR is remodeled, and the modified ligands reposition in the binding pocket to avoid clashes, but the conformational changes result in less favorable binding modes. Thus, ligand-induced binding pocket expansion increases ligand-binding potential of PXR but is an unfavorable event; therefore, drug candidates can be engineered to expand PXR's ligand-binding pocket and reduce their safety liability due to PXR binding.
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Affiliation(s)
- Wenwei Lin
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN38105
| | - Andrew D. Huber
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN38105
| | - Shyaron Poudel
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN38105
| | - Yongtao Li
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN38105
| | - Jayaraman Seetharaman
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN38105
| | - Darcie J. Miller
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN38105
| | - Taosheng Chen
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN38105
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8
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Poudel S, Huber AD, Chen T. Regulation of Nuclear Receptors PXR and CAR by Small Molecules and Signal Crosstalk: Roles in Drug Metabolism and Beyond. Drug Metab Dispos 2023; 51:228-236. [PMID: 36116789 PMCID: PMC9900866 DOI: 10.1124/dmd.122.000858] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 08/16/2022] [Accepted: 08/29/2022] [Indexed: 01/31/2023] Open
Abstract
Pregnane X receptor (PXR) and constitutive androstane receptor (CAR) are ligand-activated transcription factors that regulate the expression of drug metabolizing enzymes and drug transporters. Since their discoveries, they have been studied as important factors for regulating processes related to drug efficacy, drug toxicity, and drug-drug interactions. However, their vast ligand-binding profiles extend into additional spaces, such as endogenously produced chemicals, microbiome metabolites, dietary compounds, and environmental pollutants. Therefore, PXR and CAR can respond to an enormous abundance of stimuli, resulting in significant shifts in metabolic programs and physiologic homeostasis. Naturally, PXR and CAR have been implicated in various diseases related to homeostatic perturbations, such as inflammatory bowel disorders, diabetes, and certain cancers. Recent findings have injected the field with new signaling mechanisms and tools to dissect the complex PXR and CAR biology and have strengthened the potential for future PXR and CAR modulators in the clinic. Here, we describe the historical and ongoing importance of PXR and CAR in drug metabolism pathways and how this history has evolved into new mechanisms that regulate and are regulated by these xenobiotic receptors, with a specific focus on small molecule ligands. To effectively convey the impact of newly emerging research, we have arranged five diverse and representative key recent advances, four specific challenges, and four perspectives on future directions. SIGNIFICANCE STATEMENT: PXR and CAR are key transcription factors that regulate homeostatic detoxification of the liver and intestines. Diverse chemicals bind to these nuclear receptors, triggering their transcriptional tuning of the cellular metabolic response. This minireview revisits the importance of PXR and CAR in pharmaceutical drug responses and highlights recent results with implications beyond drug metabolism.
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Affiliation(s)
- Shyaron Poudel
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee
| | - Andrew D Huber
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee
| | - Taosheng Chen
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee
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9
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Bwayi MN, Garcia-Maldonado E, Chai SC, Xie B, Chodankar S, Huber AD, Wu J, Annu K, Wright WC, Lee HM, Seetharaman J, Wang J, Buchman CD, Peng J, Chen T. Molecular basis of crosstalk in nuclear receptors: heterodimerization between PXR and CAR and the implication in gene regulation. Nucleic Acids Res 2022; 50:3254-3275. [PMID: 35212371 PMCID: PMC8989523 DOI: 10.1093/nar/gkac133] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 01/20/2022] [Accepted: 02/11/2022] [Indexed: 02/06/2023] Open
Abstract
The 48 human nuclear receptors (NRs) form a superfamily of transcription factors that regulate major physiological and pathological processes. Emerging evidence suggests that NR crosstalk can fundamentally change our understanding of NR biology, but detailed molecular mechanisms of crosstalk are lacking. Here, we report the molecular basis of crosstalk between the pregnane X receptor (PXR) and constitutive androstane receptor (CAR), where they form a novel heterodimer, resulting in their mutual inhibition. PXR and CAR regulate drug metabolism and energy metabolism. Although they have been broadly perceived as functionally redundant, a growing number of reports suggests a mutual inhibitory relation, but their precise mode of coordinated action remains unknown. Using methods including RNA sequencing, small-angle X-ray scattering and crosslinking mass spectrometry we demonstrate that the mutual inhibition altered gene expression globally and is attributed to the novel PXR–CAR heterodimerization via the same interface used by each receptor to heterodimerize with its functional partner, retinoid X receptor (RXR). These findings establish an unexpected functional relation between PXR, CAR and RXR, change the perceived functional relation between PXR and CAR, open new perspectives on elucidating their role and designing approaches to regulate them, and highlight the importance to comprehensively investigate nuclear receptor crosstalk.
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Affiliation(s)
- Monicah N Bwayi
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA
| | - Efren Garcia-Maldonado
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA
| | - Sergio C Chai
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA
| | - Boer Xie
- Center for Proteomics and Metabolomics, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA
| | - Shirish Chodankar
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Andrew D Huber
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA
| | - Jing Wu
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA
| | - Kavya Annu
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA
| | - William C Wright
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA
| | - Hyeong-Min Lee
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA
| | - Jayaraman Seetharaman
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA
| | - Jingheng Wang
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA
| | - Cameron D Buchman
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA
| | - Junmin Peng
- Center for Proteomics and Metabolomics, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA.,Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA.,Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA
| | - Taosheng Chen
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA
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10
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Wang J, Buchman CD, Seetharaman J, Miller DJ, Huber AD, Wu J, Chai SC, Garcia-Maldonado E, Wright WC, Chenge J, Chen T. Unraveling the structural basis of selective inhibition of human cytochrome p450 3a5. Biophys J 2022. [DOI: 10.1016/j.bpj.2021.11.2511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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11
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Wang J, Buchman CD, Seetharaman J, Miller DJ, Huber AD, Wu J, Chai SC, Garcia-Maldonado E, Wright WC, Chenge J, Chen T. Unraveling the Structural Basis of Selective Inhibition of Human Cytochrome P450 3A5. J Am Chem Soc 2021; 143:18467-18480. [PMID: 34648292 DOI: 10.1021/jacs.1c07066] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The human cytochrome P450 (CYP) CYP3A4 and CYP3A5 enzymes metabolize more than one-half of marketed drugs. They share high structural and substrate similarity and are often studied together as CYP3A4/5. However, CYP3A5 preferentially metabolizes several clinically prescribed drugs, such as tacrolimus. Genetic polymorphism in CYP3A5 makes race-based dosing adjustment of tacrolimus necessary to minimize acute rejection after organ transplantation. Moreover, the differential tissue distribution and expression levels of CYP3A4 and CYP3A5 can aggravate toxicity during treatment. Therefore, selective inhibitors of CYP3A5 are needed to distinguish the role of CYP3A5 from that of CYP3A4 and serve as starting points for potential therapeutic development. To this end, we report the crystal structure of CYP3A5 in complex with a previously reported selective inhibitor, clobetasol propionate (CBZ). This is the first CYP3A5 structure with a type I inhibitor, which along with the previously reported substrate-free and type II inhibitor-bound structures, constitute the main CYP3A5 structural modalities. Supported by structure-guided mutagenesis analyses, the CYP3A5-CBZ structure showed that a unique conformation of the F-F' loop in CYP3A5 enables selective binding of CBZ to CYP3A5. Several polar interactions, including hydrogen bonds, stabilize the position of CBZ to interact with this unique F-F' loop conformation. In addition, functional and biophysical assays using CBZ analogs highlight the importance of heme-adjacent moieties for selective CYP3A5 inhibition. Our findings can be used to guide further development of more potent and selective CYP3A5 inhibitors.
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Affiliation(s)
- Jingheng Wang
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
| | - Cameron D Buchman
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
| | - Jayaraman Seetharaman
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
| | - Darcie J Miller
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
| | - Andrew D Huber
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
| | - Jing Wu
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
| | - Sergio C Chai
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
| | - Efren Garcia-Maldonado
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
| | - William C Wright
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
| | - Jude Chenge
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
| | - Taosheng Chen
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, United States
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12
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Lin W, Bwayi M, Wu J, Li Y, Chai SC, Huber AD, Chen T. CITCO Directly Binds to and Activates Human Pregnane X Receptor. Mol Pharmacol 2020; 97:180-190. [PMID: 31882411 PMCID: PMC6978709 DOI: 10.1124/mol.119.118513] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 12/23/2019] [Indexed: 12/12/2022] Open
Abstract
The xenobiotic receptors pregnane X receptor (PXR) and constitutive androstane receptor (CAR) are activated by structurally diverse chemicals to regulate the expression of target genes, and they have overlapping regulation in terms of ligands and target genes. Receptor-selective agonists are, therefore, critical for studying the overlapping function of PXR and CAR. An early effort identified 6-(4-chlorophenyl)imidazo[2,1-b][1,3]thiazole-5-carbaldehyde-O-(3,4-dichlorobenzyl)oxime (CITCO) as a selective human CAR (hCAR) agonist, and this has since been widely used to distinguish the function of hCAR from that of human PXR (hPXR). The selectivity was demonstrated in a green monkey kidney cell line, CV-1, in which CITCO displayed >100-fold selectivity for hCAR over hPXR. However, whether the selectivity observed in CV-1 cells also represented CITCO activity in liver cell models was not hitherto investigated. In this study, we showed that CITCO: 1) binds directly to hPXR; 2) activates hPXR in HepG2 cells, with activation being blocked by an hPXR-specific antagonist, SPA70; 3) does not activate mouse PXR; 4) depends on tryptophan-299 to activate hPXR; 5) recruits steroid receptor coactivator 1 to hPXR; 6) activates hPXR in HepaRG cell lines even when hCAR is knocked out; and 7) activates hPXR in primary human hepatocytes. Together, these data indicate that CITCO binds directly to the hPXR ligand-binding domain to activate hPXR. As CITCO has been widely used, its confirmation as a dual agonist for hCAR and hPXR is important for appropriately interpreting existing data and designing future experiments to understand the regulation of hPXR and hCAR. SIGNIFICANCE STATEMENT: The results of this study demonstrate that 6-(4-chlorophenyl)imidazo[2,1-b][1,3]thiazole-5-carbaldehyde-O-(3,4-dichlorobenzyl)oxime (CITCO) is a dual agonist for human constitutive androstane receptor (hCAR) and human pregnane X receptor (hPXR). As CITCO has been widely used to activate hCAR, and hPXR and hCAR have distinct and overlapping biological functions, these results highlight the value of receptor-selective agonists and the importance of appropriately interpreting data in the context of receptor selectivity of such agonists.
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Affiliation(s)
- Wenwei Lin
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee
| | - Monicah Bwayi
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee
| | - Jing Wu
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee
| | - Yongtao Li
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee
| | - Sergio C Chai
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee
| | - Andrew D Huber
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee
| | - Taosheng Chen
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee
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13
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Wright WC, Chenge J, Wang J, Girvan HM, Yang L, Chai SC, Huber AD, Wu J, Oladimeji PO, Munro AW, Chen T. Clobetasol Propionate Is a Heme-Mediated Selective Inhibitor of Human Cytochrome P450 3A5. J Med Chem 2020; 63:1415-1433. [PMID: 31965799 PMCID: PMC7087482 DOI: 10.1021/acs.jmedchem.9b02067] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The human cytochrome P450 (CYP) enzymes CYP3A4 and CYP3A5 metabolize most drugs and have high similarities in their structure and substrate preference. Whereas CYP3A4 is predominantly expressed in the liver, CYP3A5 is upregulated in cancer, contributing to drug resistance. Selective inhibitors of CYP3A5 are, therefore, critical to validating it as a therapeutic target. Here we report clobetasol propionate (clobetasol) as a potent and selective CYP3A5 inhibitor identified by high-throughput screening using enzymatic and cell-based assays. Molecular dynamics simulations suggest a close proximity of clobetasol to the heme in CYP3A5 but not in CYP3A4. UV-visible spectroscopy and electron paramagnetic resonance analyses confirmed the formation of an inhibitory type I heme-clobetasol complex in CYP3A5 but not in CYP3A4, thus explaining the CYP3A5 selectivity of clobetasol. Our results provide a structural basis for selective CYP3A5 inhibition, along with mechanistic insights, and highlight clobetasol as an important chemical tool for target validation.
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Affiliation(s)
- William C. Wright
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105-3678, USA
- Integrated Biomedical Sciences Program, University of
Tennessee Health Science Center, Memphis, Tennessee 38163, USA
| | - Jude Chenge
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105-3678, USA
| | - Jingheng Wang
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105-3678, USA
| | - Hazel M. Girvan
- Manchester Institute of Biotechnology, School of Natural
Sciences, Department of Chemistry, The University of Manchester, Manchester, M1 7DN,
UK
| | - Lei Yang
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105-3678, USA
| | - Sergio C. Chai
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105-3678, USA
| | - Andrew D. Huber
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105-3678, USA
| | - Jing Wu
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105-3678, USA
| | - Peter O. Oladimeji
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105-3678, USA
| | - Andrew W. Munro
- Manchester Institute of Biotechnology, School of Natural
Sciences, Department of Chemistry, The University of Manchester, Manchester, M1 7DN,
UK
| | - Taosheng Chen
- Department of Chemical Biology and Therapeutics, St. Jude
Children’s Research Hospital, Memphis, Tennessee 38105-3678, USA
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14
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Huber AD, Chen T. Discovering Anti-cancer Immune Enhancers in a Miniaturized Immune-Tumor Microenvironment. Cell Chem Biol 2019; 26:314-316. [PMID: 30901558 DOI: 10.1016/j.chembiol.2019.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In this issue of Cell Chemical Biology, Mo et al. (2019) report the development and validation of a co-culture system with cancer and immune cells that is suitable for high-throughput screening. The method is an important step forward in technologies for identifying cancer-cell-specific immunotherapies.
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Affiliation(s)
- Andrew D Huber
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Taosheng Chen
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
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15
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Puray-Chavez MN, Farghali MH, Yapo V, Huber AD, Liu D, Ndongwe TP, Casey MC, Laughlin TG, Hannink M, Tedbury PR, Sarafianos SG. Effects of Moloney Leukemia Virus 10 Protein on Hepatitis B Virus Infection and Viral Replication. Viruses 2019; 11:v11070651. [PMID: 31319455 PMCID: PMC6669478 DOI: 10.3390/v11070651] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 07/09/2019] [Accepted: 07/11/2019] [Indexed: 12/16/2022] Open
Abstract
Moloney leukemia virus 10 (MOV10) is an RNA helicase that has been shown to affect the replication of several viruses. The effect of MOV10 on Hepatitis B virus (HBV) infection is not known and its role on the replication of this virus is poorly understood. We investigated the effect of MOV10 down-regulation and MOV10 over-expression on HBV in a variety of cell lines, as well as in an infection system using a replication competent virus. We report that MOV10 down-regulation, using siRNA, shRNA, and CRISPR/Cas9 gene editing technology, resulted in increased levels of HBV DNA, HBV pre-genomic RNA, and HBV core protein. In contrast, MOV10 over-expression reduced HBV DNA, HBV pre-genomic RNA, and HBV core protein. These effects were consistent in all tested cell lines, providing strong evidence for the involvement of MOV10 in the HBV life cycle. We demonstrated that MOV10 does not interact with HBV-core. However, MOV10 binds HBV pgRNA and this interaction does not affect HBV pgRNA decay rate. We conclude that the restriction of HBV by MOV10 is mediated through effects at the level of viral RNA.
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Affiliation(s)
- Maritza N Puray-Chavez
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Mahmoud H Farghali
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
- Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Tanta University, Tanta QXXV+C5, Egypt
| | - Vincent Yapo
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Andrew D Huber
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
| | - Dandan Liu
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Tanyaradzwa P Ndongwe
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Mary C Casey
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Thomas G Laughlin
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Department of Biochemistry, University of Missouri, Columbia, MO 65211, USA
| | - Mark Hannink
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Department of Biochemistry, University of Missouri, Columbia, MO 65211, USA
| | - Philip R Tedbury
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA.
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA.
| | - Stefan G Sarafianos
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA.
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA.
- Department of Biochemistry, University of Missouri, Columbia, MO 65211, USA.
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16
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Huber AD, Pineda DL, Liu D, Boschert KN, Gres AT, Wolf JJ, Coonrod EM, Tang J, Laughlin TG, Yang Q, Puray-Chavez MN, Ji J, Singh K, Kirby KA, Wang Z, Sarafianos SG. Novel Hepatitis B Virus Capsid-Targeting Antiviral That Aggregates Core Particles and Inhibits Nuclear Entry of Viral Cores. ACS Infect Dis 2019; 5:750-758. [PMID: 30582687 DOI: 10.1021/acsinfecdis.8b00235] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
An estimated 240 million are chronically infected with hepatitis B virus (HBV), which can lead to liver disease, cirrhosis, and hepatocellular carcinoma. Currently, HBV treatment options include only nucleoside reverse transcriptase inhibitors and the immunomodulatory agent interferon alpha, and these treatments are generally not curative. New treatments with novel mechanisms of action, therefore, are highly desired for HBV therapy. The viral core protein (Cp) has gained attention as a possible therapeutic target because of its vital roles in the HBV life cycle. Several classes of capsid assembly effectors (CAEs) have been described in detail, and these compounds all increase capsid assembly rate but inhibit HBV replication by different mechanisms. In this study, we have developed a thermal shift-based screening method for CAE discovery and characterization, filling a much-needed gap in high-throughput screening methods for capsid-targeting molecules. Using this approach followed by cell-based screening, we identified the compound HF9C6 as a CAE with low micromolar potency against HBV replication. HF9C6 caused large multicapsid aggregates when capsids were assembled in vitro and analyzed by transmission electron microscopy. Interestingly, when HBV-expressing cells were treated with HF9C6, Cp was excluded from cell nuclei, suggesting that this compound may inhibit nuclear entry of Cp and capsids. Furthermore, mutational scanning of Cp suggested that HF9C6 binds the known CAE binding pocket, indicating that key Cp-compound interactions within this pocket have a role in determining the CAE mechanism of action.
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Affiliation(s)
- Andrew D. Huber
- Christopher S. Bond Life Sciences Center, University of Missouri, 1201 E. Rollins St., Columbia, Missouri 65211, United States
| | - Dallas L. Pineda
- Christopher S. Bond Life Sciences Center, University of Missouri, 1201 E. Rollins St., Columbia, Missouri 65211, United States
- Department of Biochemistry, University of Missouri, 117 Schweitzer Hall, Columbia, Missouri 65211, United States
| | - Dandan Liu
- Christopher S. Bond Life Sciences Center, University of Missouri, 1201 E. Rollins St., Columbia, Missouri 65211, United States
- Department of Molecular Microbiology & Immunology, University of Missouri School of Medicine, M616 Medical Sciences Building, Columbia, Missouri 65211, United States
| | - Kelsey N. Boschert
- Christopher S. Bond Life Sciences Center, University of Missouri, 1201 E. Rollins St., Columbia, Missouri 65211, United States
- Department of Nutrition and Exercise Physiology, University of Missouri, 204 Gwynn Hall, Columbia, Missouri 65211, United States
| | - Anna T. Gres
- Christopher S. Bond Life Sciences Center, University of Missouri, 1201 E. Rollins St., Columbia, Missouri 65211, United States
- Department of Chemistry, University of Missouri, 125 Chemistry Building, Columbia, Missouri 65211, United States
| | - Jennifer J. Wolf
- Christopher S. Bond Life Sciences Center, University of Missouri, 1201 E. Rollins St., Columbia, Missouri 65211, United States
- Department of Molecular Microbiology & Immunology, University of Missouri School of Medicine, M616 Medical Sciences Building, Columbia, Missouri 65211, United States
| | - Emily M. Coonrod
- Christopher S. Bond Life Sciences Center, University of Missouri, 1201 E. Rollins St., Columbia, Missouri 65211, United States
- Division of Biological Sciences, University of Missouri, 105 Tucker Hall, Columbia, Missouri 65211, United States
| | - Jing Tang
- Center for Drug Design, Academic Health Center, University of Minnesota, 312 Church St. SE, Minneapolis, Minnesota 55455, United States
| | - Thomas G. Laughlin
- Christopher S. Bond Life Sciences Center, University of Missouri, 1201 E. Rollins St., Columbia, Missouri 65211, United States
- Department of Biochemistry, University of Missouri, 117 Schweitzer Hall, Columbia, Missouri 65211, United States
| | - Qiongying Yang
- Christopher S. Bond Life Sciences Center, University of Missouri, 1201 E. Rollins St., Columbia, Missouri 65211, United States
- Department of Molecular Microbiology & Immunology, University of Missouri School of Medicine, M616 Medical Sciences Building, Columbia, Missouri 65211, United States
| | - Maritza N. Puray-Chavez
- Christopher S. Bond Life Sciences Center, University of Missouri, 1201 E. Rollins St., Columbia, Missouri 65211, United States
- Department of Molecular Microbiology & Immunology, University of Missouri School of Medicine, M616 Medical Sciences Building, Columbia, Missouri 65211, United States
| | - Juan Ji
- Christopher S. Bond Life Sciences Center, University of Missouri, 1201 E. Rollins St., Columbia, Missouri 65211, United States
- Department of Molecular Microbiology & Immunology, University of Missouri School of Medicine, M616 Medical Sciences Building, Columbia, Missouri 65211, United States
| | - Kamalendra Singh
- Christopher S. Bond Life Sciences Center, University of Missouri, 1201 E. Rollins St., Columbia, Missouri 65211, United States
- Department of Molecular Microbiology & Immunology, University of Missouri School of Medicine, M616 Medical Sciences Building, Columbia, Missouri 65211, United States
| | - Karen A. Kirby
- Christopher S. Bond Life Sciences Center, University of Missouri, 1201 E. Rollins St., Columbia, Missouri 65211, United States
- Department of Molecular Microbiology & Immunology, University of Missouri School of Medicine, M616 Medical Sciences Building, Columbia, Missouri 65211, United States
| | - Zhengqiang Wang
- Center for Drug Design, Academic Health Center, University of Minnesota, 312 Church St. SE, Minneapolis, Minnesota 55455, United States
| | - Stefan G. Sarafianos
- Christopher S. Bond Life Sciences Center, University of Missouri, 1201 E. Rollins St., Columbia, Missouri 65211, United States
- Department of Biochemistry, University of Missouri, 117 Schweitzer Hall, Columbia, Missouri 65211, United States
- Department of Molecular Microbiology & Immunology, University of Missouri School of Medicine, M616 Medical Sciences Building, Columbia, Missouri 65211, United States
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17
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Tang J, Do HT, Huber AD, Casey MC, Kirby KA, Wilson DJ, Kankanala J, Parniak MA, Sarafianos SG, Wang Z. Pharmacophore-based design of novel 3-hydroxypyrimidine-2,4-dione subtypes as inhibitors of HIV reverse transcriptase-associated RNase H: Tolerance of a nonflexible linker. Eur J Med Chem 2019; 166:390-399. [PMID: 30739822 PMCID: PMC6459026 DOI: 10.1016/j.ejmech.2019.01.081] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 01/17/2019] [Accepted: 01/30/2019] [Indexed: 11/29/2022]
Abstract
The pharmacophore of active site inhibitors of human immunodeficiency virus (HIV) reverse transcriptase (RT)-associated RNase H typically entails a flexible linker connecting the chelating core and the hydrophobic aromatics. We report herein that novel 3-hydroxypyrimidine-2,4-dione (HPD) subtypes with a nonflexible C-6 carbonyl linkage exhibited potent and selective biochemical inhibitory profiles with strong RNase H inhibition at low nM, weak to moderate integrase strand transfer (INST) inhibition at low μM, and no to marginal RT polymerase (pol) inhibition up to 10 μM. A few analogues also demonstrated significant antiviral activity without cytotoxicity. The overall inhibitory profile is comparable to or better than that of previous HPD subtypes with a flexible C-6 linker, suggesting that the nonflexible carbonyl linker can be tolerated in the design of novel HIV RNase H active site inhibitors.
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Affiliation(s)
- Jing Tang
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Ha T Do
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Andrew D Huber
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Christopher S. Bond Life Sciences Center, Columbia, MO, 65211, USA
| | - Mary C Casey
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Christopher S. Bond Life Sciences Center, Columbia, MO, 65211, USA
| | - Karen A Kirby
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Christopher S. Bond Life Sciences Center, Columbia, MO, 65211, USA; Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Daniel J Wilson
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Jayakanth Kankanala
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Michael A Parniak
- Department of Microbiology & Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15219, USA
| | - Stefan G Sarafianos
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Christopher S. Bond Life Sciences Center, Columbia, MO, 65211, USA; Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA; Department of Biochemistry, University of Missouri, Columbia, MO, 65211, USA
| | - Zhengqiang Wang
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN, 55455, USA.
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18
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Tang J, Huber AD, Pineda DL, Boschert KN, Wolf JJ, Kankanala J, Xie J, Sarafianos SG, Wang Z. 5-Aminothiophene-2,4-dicarboxamide analogues as hepatitis B virus capsid assembly effectors. Eur J Med Chem 2019; 164:179-192. [PMID: 30594676 PMCID: PMC6362850 DOI: 10.1016/j.ejmech.2018.12.047] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 12/06/2018] [Accepted: 12/19/2018] [Indexed: 02/08/2023]
Abstract
Chronic hepatitis B virus (HBV) infection represents a major health threat. Current FDA-approved drugs do not cure HBV. Targeting HBV core protein (Cp) provides an attractive approach toward HBV inhibition and possibly infection cure. We have previously identified and characterized a 5-amino-3-methylthiophene-2,4-dicarboxamide (ATDC) compound as a structurally novel hit for capsid assembly effectors (CAEs). We report herein hit validation through studies on absorption, distribution, metabolism and excretion (ADME) properties and pharmacokinetics (PK), and hit optimization via analogue synthesis aiming to probe the structure-activity relationship (SAR) and structure-property relationship (SPR). In the end, these medicinal chemistry efforts led to the identification of multiple analogues strongly binding to Cp, potently inhibiting HBV replication in nanomolar range without cytotoxicity, and exhibiting good oral bioavailability (F). Two of our analogues, 19o (EC50 = 0.11 μM, CC50 > 100 μM, F = 25%) and 19k (EC50 = 0.31 μM, CC50 > 100 μM, F = 46%), displayed overall lead profiles superior to reported CAEs 7-10 used in our studies.
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Affiliation(s)
- Jing Tang
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Andrew D Huber
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA; Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO, 65211, USA
| | - Dallas L Pineda
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA; Department of Biochemistry, University of Missouri, Columbia, MO, 65211, USA
| | - Kelsey N Boschert
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA; Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, 65211, USA
| | - Jennifer J Wolf
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA; Department of Molecular Microbiology & Immunology, School of Medicine, University of Missouri, Columbia, MO, 65211, USA
| | - Jayakanth Kankanala
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Jiashu Xie
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Stefan G Sarafianos
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA; Department of Biochemistry, University of Missouri, Columbia, MO, 65211, USA; Department of Molecular Microbiology & Immunology, School of Medicine, University of Missouri, Columbia, MO, 65211, USA
| | - Zhengqiang Wang
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN, 55455, USA.
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19
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Wang L, Tang J, Huber AD, Casey MC, Kirby KA, Wilson DJ, Kankanala J, Parniak MA, Sarafianos SG, Wang Z. 6-Biphenylmethyl-3-hydroxypyrimidine-2,4-diones potently and selectively inhibited HIV reverse transcriptase-associated RNase H. Eur J Med Chem 2018; 156:680-691. [PMID: 30031978 DOI: 10.1016/j.ejmech.2018.07.035] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 07/11/2018] [Accepted: 07/14/2018] [Indexed: 12/11/2022]
Abstract
Human immunodeficiency virus (HIV) reverse transcriptase (RT)-associated ribonuclease H (RNase H) remains an unvalidated drug target. Reported HIV RNase H inhibitors generally lack significant antiviral activity. We report herein the design, synthesis, biochemical and antiviral evaluations of a new 6-biphenylmethyl subtype of the 3-hydroxypyrimidine-2,4-dione (HPD) chemotype. In biochemical assays, analogues of this new subtype potently inhibited RT RNase H in low nanomolar range without inhibiting RT polymerase (pol) or integrase strand transfer (INST) at the highest concentrations tested. In cell-based assays, a few analogues inhibited HIV in low micromolar range without cytotoxicity at concentrations up to 100 μM.
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Affiliation(s)
- Lei Wang
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Jing Tang
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Andrew D Huber
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Christopher S. Bond Life Sciences Center, Columbia, MO 65211, USA
| | - Mary C Casey
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Christopher S. Bond Life Sciences Center, Columbia, MO 65211, USA
| | - Karen A Kirby
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Christopher S. Bond Life Sciences Center, Columbia, MO 65211, USA; Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Daniel J Wilson
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Jayakanth Kankanala
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Michael A Parniak
- Department of Microbiology & Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15219, USA
| | - Stefan G Sarafianos
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Christopher S. Bond Life Sciences Center, Columbia, MO 65211, USA; Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30322, USA; Department of Biochemistry, University of Missouri, Columbia, MO 65211, USA
| | - Zhengqiang Wang
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455, USA.
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20
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Wang L, Tang J, Huber AD, Casey MC, Kirby KA, Wilson DJ, Kankanala J, Xie J, Parniak MA, Sarafianos SG, Wang Z. 6-Arylthio-3-hydroxypyrimidine-2,4-diones potently inhibited HIV reverse transcriptase-associated RNase H with antiviral activity. Eur J Med Chem 2018; 156:652-665. [PMID: 30031976 DOI: 10.1016/j.ejmech.2018.07.039] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 05/31/2018] [Accepted: 07/15/2018] [Indexed: 12/17/2022]
Abstract
Human immunodeficiency virus (HIV) reverse transcriptase (RT) associated ribonuclease H (RNase H) remains the only virally encoded enzymatic function not targeted by current drugs. Although a few chemotypes have been reported to inhibit HIV RNase H in biochemical assays, their general lack of significant antiviral activity in cell culture necessitates continued efforts in identifying highly potent RNase H inhibitors to confer antiviral activity. We report herein the design, synthesis, biochemical and antiviral evaluations of a new 6-arylthio subtype of the 3-hydroxypyrimidine-2,4-dione (HPD) chemotype. In biochemical assays these new analogues inhibited RT RNase H in single-digit nanomolar range without inhibiting RT polymerase (pol) at concentrations up to 10 μM, amounting to exceptional biochemical inhibitory selectivity. Many analogues also inhibited integrase strand transfer (INST) activity in low to sub micromolar range. More importantly, most analogues inhibited HIV in low micromolar range without cytotoxicity. In the end, compound 13j (RNase H IC50 = 0.005 μM; RT pol IC50 = 10 μM; INST IC50 = 4.0 μM; antiviral EC50 = 7.7 μM; CC50 > 100 μM) represents the best analogues within this series. These results characterize the new 6-arylthio-HPD subtype as a promising scaffold for HIV RNase H inhibitor discovery.
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Affiliation(s)
- Lei Wang
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Jing Tang
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Andrew D Huber
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Christopher S. Bond Life Sciences Center, Columbia, MO, 65211, USA
| | - Mary C Casey
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Christopher S. Bond Life Sciences Center, Columbia, MO, 65211, USA
| | - Karen A Kirby
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Christopher S. Bond Life Sciences Center, Columbia, MO, 65211, USA; Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Daniel J Wilson
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Jayakanth Kankanala
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Jiashu Xie
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Michael A Parniak
- Department of Microbiology & Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15219, USA
| | - Stefan G Sarafianos
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Christopher S. Bond Life Sciences Center, Columbia, MO, 65211, USA; Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA; Department of Biochemistry, University of Missouri, Christopher S. Bond Life Sciences Center, Columbia, MO, 65211, USA
| | - Zhengqiang Wang
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN, 55455, USA.
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21
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Puray-Chavez M, Tedbury PR, Huber AD, Ukah OB, Yapo V, Liu D, Ji J, Wolf JJ, Engelman AN, Sarafianos SG. Multiplex single-cell visualization of nucleic acids and protein during HIV infection. Nat Commun 2017; 8:1882. [PMID: 29192235 PMCID: PMC5709414 DOI: 10.1038/s41467-017-01693-z] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 10/05/2017] [Indexed: 01/09/2023] Open
Abstract
Technical limitations in simultaneous microscopic visualization of RNA, DNA, and proteins of HIV have curtailed progress in this field. To address this need we develop a microscopy approach, multiplex immunofluorescent cell-based detection of DNA, RNA and Protein (MICDDRP), which is based on branched DNA in situ hybridization technology. MICDDRP enables simultaneous single-cell visualization of HIV (a) spliced and unspliced RNA, (b) cytoplasmic and nuclear DNA, and (c) Gag. We use MICDDRP to visualize incoming capsid cores containing RNA and/or nascent DNA and follow reverse transcription kinetics. We also report transcriptional “bursts” of nascent RNA from integrated proviral DNA, and concomitant HIV-1, HIV-2 transcription in co-infected cells. MICDDRP can be used to simultaneously detect multiple viral nucleic acid intermediates, characterize the effects of host factors or drugs on steps of the HIV life cycle, or its reactivation from the latent state, thus facilitating the development of antivirals and latency reactivating agents. Technical limitations in simultaneous microscopic visualization of HIV transcription from individual integration sites have curtailed progress in the field. Here the authors report a branched DNA in situ hybridization method for direct single-cell visualization of HIV DNA, RNA, and protein.
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Affiliation(s)
- Maritza Puray-Chavez
- CS Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA.,Department of Molecular Microbiology & Immunology, University of Missouri School of Medicine, Columbia, MO, 65212, USA
| | - Philip R Tedbury
- CS Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA.,Department of Molecular Microbiology & Immunology, University of Missouri School of Medicine, Columbia, MO, 65212, USA.,Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30332, USA
| | - Andrew D Huber
- CS Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA.,Department of Veterinary Pathobiology, University of Missouri, Columbia, MO, 65211, USA
| | - Obiaara B Ukah
- CS Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA.,Department of Molecular Microbiology & Immunology, University of Missouri School of Medicine, Columbia, MO, 65212, USA
| | - Vincent Yapo
- CS Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA.,Department of Molecular Microbiology & Immunology, University of Missouri School of Medicine, Columbia, MO, 65212, USA
| | - Dandan Liu
- CS Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA.,Department of Molecular Microbiology & Immunology, University of Missouri School of Medicine, Columbia, MO, 65212, USA
| | - Juan Ji
- CS Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA
| | - Jennifer J Wolf
- CS Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA.,Department of Molecular Microbiology & Immunology, University of Missouri School of Medicine, Columbia, MO, 65212, USA
| | - Alan N Engelman
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA, 02215, USA.,Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA
| | - Stefan G Sarafianos
- CS Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA. .,Department of Molecular Microbiology & Immunology, University of Missouri School of Medicine, Columbia, MO, 65212, USA. .,Department of Veterinary Pathobiology, University of Missouri, Columbia, MO, 65211, USA. .,Department of Biochemistry, University of Missouri, Columbia, MO, 65201, USA. .,Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30332, USA.
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22
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Kankanala J, Kirby KA, Huber AD, Casey MC, Wilson DJ, Sarafianos SG, Wang Z. Design, synthesis and biological evaluations of N-Hydroxy thienopyrimidine-2,4-diones as inhibitors of HIV reverse transcriptase-associated RNase H. Eur J Med Chem 2017; 141:149-161. [PMID: 29031062 DOI: 10.1016/j.ejmech.2017.09.054] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 09/13/2017] [Accepted: 09/25/2017] [Indexed: 11/29/2022]
Abstract
Human immunodeficiency virus (HIV) reverse transcriptase (RT) associated ribonuclease H (RNase H) is the only HIV enzymatic function not targeted by current antiviral drugs. Although various chemotypes have been reported to inhibit HIV RNase H, few have shown significant antiviral activities. We report herein the design, synthesis and biological evaluation of a novel N-hydroxy thienopyrimidine-2,3-dione chemotype (11) which potently and selectively inhibited RNase H with considerable potency against HIV-1 in cell culture. Current structure-activity-relationship (SAR) identified analogue 11d as a nanomolar inhibitor of RNase H (IC50 = 0.04 μM) with decent antiviral potency (EC50 = 7.4 μM) and no cytotoxicity (CC50 > 100 μM). In extended biochemical assays compound 11d did not inhibit RT polymerase (pol) while inhibiting integrase strand transfer (INST) with 53 fold lower potency (IC50 = 2.1 μM) than RNase H inhibition. Crystallographic and molecular modeling studies confirmed the RNase H active site binding mode.
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Affiliation(s)
- Jayakanth Kankanala
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Karen A Kirby
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA; Department of Molecular Microbiology & Immunology, School of Medicine, University of Missouri, Columbia, MO 65211, USA
| | - Andrew D Huber
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA; Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA
| | - Mary C Casey
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA; Department of Molecular Microbiology & Immunology, School of Medicine, University of Missouri, Columbia, MO 65211, USA
| | - Daniel J Wilson
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Stefan G Sarafianos
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA; Department of Molecular Microbiology & Immunology, School of Medicine, University of Missouri, Columbia, MO 65211, USA; Department of Biochemistry, University of Missouri, Columbia, MO 65211, USA
| | - Zhengqiang Wang
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455, USA.
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23
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Vernekar SKV, Tang J, Wu B, Huber AD, Casey MC, Myshakina N, Wilson DJ, Kankanala J, Kirby KA, Parniak MA, Sarafianos SG, Wang Z. Double-Winged 3-Hydroxypyrimidine-2,4-diones: Potent and Selective Inhibition against HIV-1 RNase H with Significant Antiviral Activity. J Med Chem 2017; 60:5045-5056. [PMID: 28525279 DOI: 10.1021/acs.jmedchem.7b00440] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Human immunodeficiency virus (HIV) reverse transcriptase (RT)-associated ribonuclease H (RNase H) remains the only virally encoded enzymatic function yet to be exploited as an antiviral target. One of the possible challenges may be that targeting HIV RNase H is confronted with a steep substrate barrier. We have previously reported a 3-hydroxypyrimidine-2,4-dione (HPD) subtype that potently and selectively inhibited RNase H without inhibiting HIV in cell culture. We report herein a critical redesign of the HPD chemotype featuring an additional wing at the C5 position that led to drastically improved RNase H inhibition and significant antiviral activity. Structure-activity relationship (SAR) concerning primarily the length and flexibility of the two wings revealed important structural features that dictate the potency and selectivity of RNase H inhibition as well as the observed antiviral activity. Our current medicinal chemistry data also revealed that the RNase H biochemical inhibition largely correlated the antiviral activity.
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Affiliation(s)
- Sanjeev Kumar V Vernekar
- Center for Drug Design, Academic Health Center, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Jing Tang
- Center for Drug Design, Academic Health Center, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Bulan Wu
- Center for Drug Design, Academic Health Center, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Andrew D Huber
- Department of Veterinary Pathobiology, Christopher S. Bond Life Sciences Center, University of Missouri , Columbia, Missouri 65211, United States
| | - Mary C Casey
- Department of Molecular Microbiology and Immunology, Christopher S. Bond Life Sciences Center, University of Missouri School of Medicine , Columbia, Missouri 65211, United States
| | - Nataliya Myshakina
- Department of Natural Science, Chatham University , 1 Woodland Road, Pittsburgh, Pennsylvania 15232, United States
| | - Daniel J Wilson
- Center for Drug Design, Academic Health Center, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Jayakanth Kankanala
- Center for Drug Design, Academic Health Center, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Karen A Kirby
- Department of Molecular Microbiology and Immunology, Christopher S. Bond Life Sciences Center, University of Missouri School of Medicine , Columbia, Missouri 65211, United States
| | - Michael A Parniak
- Department of Microbiology & Molecular Genetics, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania 15219, United States
| | - Stefan G Sarafianos
- Department of Molecular Microbiology and Immunology, Christopher S. Bond Life Sciences Center, University of Missouri School of Medicine , Columbia, Missouri 65211, United States.,Department of Biochemistry, University of Missouri , Columbia, Missouri 65211, United States
| | - Zhengqiang Wang
- Center for Drug Design, Academic Health Center, University of Minnesota , Minneapolis, Minnesota 55455, United States
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24
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Tang J, Vernekar SKV, Chen YL, Miller L, Huber AD, Myshakina N, Sarafianos SG, Parniak MA, Wang Z. Synthesis, biological evaluation and molecular modeling of 2-Hydroxyisoquinoline-1,3-dione analogues as inhibitors of HIV reverse transcriptase associated ribonuclease H and polymerase. Eur J Med Chem 2017; 133:85-96. [PMID: 28384548 DOI: 10.1016/j.ejmech.2017.03.059] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 03/21/2017] [Accepted: 03/24/2017] [Indexed: 12/12/2022]
Abstract
Human immunodeficiency virus (HIV) reverse transcriptase (RT) associated ribonuclease H (RNase H) remains the only virally encoded enzymatic function not clinically validated as an antiviral target. 2-Hydroxyisoquinoline-1,3-dione (HID) is known to confer active site directed inhibition of divalent metal-dependent enzymatic functions, such as HIV RNase H, integrase (IN) and hepatitis C virus (HCV) NS5B polymerase. We report herein the synthesis and biochemical evaluation of a few C-5, C-6 or C-7 substituted HID subtypes as HIV RNase H inhibitors. Our data indicate that while some of these subtypes inhibited both the RNase H and polymerase (pol) functions of RT, potent and selective RNase H inhibition was achieved with subtypes 8-9 as exemplified with compounds 8c and 9c.
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Affiliation(s)
- Jing Tang
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Sanjeev Kumar V Vernekar
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Yue-Lei Chen
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Lena Miller
- Department of Microbiology & Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15219, USA
| | - Andrew D Huber
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA; Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65211, USA
| | - Nataliya Myshakina
- Department of Natural Science, Chatham University, 1 Woodland Road, Pittsburgh, PA 15232, USA
| | - Stefan G Sarafianos
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA; Department of Molecular Microbiology & Immunology, University of Missouri School of Medicine, Columbia, MO 65211, USA; Department of Biochemistry, University of Missouri, Columbia, MO 65211, USA
| | - Michael A Parniak
- Department of Microbiology & Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15219, USA
| | - Zhengqiang Wang
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455, USA.
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25
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Tang J, Kirby KA, Huber AD, Casey MC, Ji J, Wilson DJ, Sarafianos SG, Wang Z. 6-Cyclohexylmethyl-3-hydroxypyrimidine-2,4-dione as an inhibitor scaffold of HIV reverase transcriptase: Impacts of the 3-OH on inhibiting RNase H and polymerase. Eur J Med Chem 2017; 128:168-179. [PMID: 28182989 DOI: 10.1016/j.ejmech.2017.01.041] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 01/25/2017] [Accepted: 01/27/2017] [Indexed: 01/24/2023]
Abstract
3-Hydroxypyrimidine-2,4-dione (HPD) represents a versatile chemical core in the design of inhibitors of human immunodeficiency virus (HIV) reverse transcriptase (RT)-associated RNase H and integrase strand transfer (INST). We report herein the design, synthesis and biological evaluation of an HPD subtype (4) featuring a cyclohexylmethyl group at the C-6 position. Antiviral testing showed that most analogues of 4 inhibited HIV-1 in the low nanomolar to submicromolar range, without cytotoxicity at concentrations up to 100 μM. Biochemically, these analogues dually inhibited both the polymerase (pol) and the RNase H functions of RT, but not INST. Co-crystal structure of 4a with RT revealed a nonnucleoside RT inhibitor (NNRTI) binding mode. Interestingly, chemotype 11, the synthetic precursor of 4 lacking the 3-OH group, did not inhibit RNase H while potently inhibiting pol. By virtue of the potent antiviral activity and biochemical RNase H inhibition, HPD subtype 4 could provide a viable platform for eventually achieving potent and selective RNase H inhibition through further medicinal chemistry.
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Affiliation(s)
- Jing Tang
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Karen A Kirby
- Department of Molecular Microbiology and Immunology and Department of Biochemistry, University of Missouri School of Medicine, Christopher S. Bond Life Sciences Center, Columbia, MO 65211, USA
| | - Andrew D Huber
- Department of Molecular Microbiology and Immunology and Department of Biochemistry, University of Missouri School of Medicine, Christopher S. Bond Life Sciences Center, Columbia, MO 65211, USA
| | - Mary C Casey
- Department of Molecular Microbiology and Immunology and Department of Biochemistry, University of Missouri School of Medicine, Christopher S. Bond Life Sciences Center, Columbia, MO 65211, USA
| | - Juan Ji
- Department of Molecular Microbiology and Immunology and Department of Biochemistry, University of Missouri School of Medicine, Christopher S. Bond Life Sciences Center, Columbia, MO 65211, USA
| | - Daniel J Wilson
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455, USA
| | - Stefan G Sarafianos
- Department of Molecular Microbiology and Immunology and Department of Biochemistry, University of Missouri School of Medicine, Christopher S. Bond Life Sciences Center, Columbia, MO 65211, USA
| | - Zhengqiang Wang
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455, USA.
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26
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Wu B, Tang J, Wilson DJ, Huber AD, Casey MC, Ji J, Kankanala J, Xie J, Sarafianos SG, Wang Z. 3-Hydroxypyrimidine-2,4-dione-5-N-benzylcarboxamides Potently Inhibit HIV-1 Integrase and RNase H. J Med Chem 2016; 59:6136-48. [PMID: 27283261 DOI: 10.1021/acs.jmedchem.6b00040] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Resistance selection by human immunodeficiency virus (HIV) toward known drug regimens necessitates the discovery of structurally novel antivirals with a distinct resistance profile. On the basis of our previously reported 3-hydroxypyrimidine-2,4-dione (HPD) core, we have designed and synthesized a new integrase strand transfer (INST) inhibitor type featuring a 5-N-benzylcarboxamide moiety. Significantly, the 6-alkylamino variant of this new chemotype consistently conferred low nanomolar inhibitory activity against HIV-1. Extended antiviral testing against a few raltegravir-resistant HIV-1 clones revealed a resistance profile similar to that of the second generation INST inhibitor (INSTI) dolutegravir. Although biochemical testing and molecular modeling also strongly corroborate the inhibition of INST as the antiviral mechanism of action, selected antiviral analogues also potently inhibited reverse transcriptase (RT) associated RNase H, implying potential dual target inhibition. In vitro ADME assays demonstrated that this novel chemotype possesses largely favorable physicochemical properties suitable for further development.
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Affiliation(s)
- Bulan Wu
- Center for Drug Design, Academic Health Center, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Jing Tang
- Center for Drug Design, Academic Health Center, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Daniel J Wilson
- Center for Drug Design, Academic Health Center, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Andrew D Huber
- Department of Molecular Microbiology and Immunology and Department of Biochemistry, Christopher S. Bond Life Sciences Center, University of Missouri , Columbia, Missouri 65211, United States
| | - Mary C Casey
- Department of Molecular Microbiology and Immunology and Department of Biochemistry, Christopher S. Bond Life Sciences Center, University of Missouri , Columbia, Missouri 65211, United States
| | - Juan Ji
- Department of Molecular Microbiology and Immunology and Department of Biochemistry, Christopher S. Bond Life Sciences Center, University of Missouri , Columbia, Missouri 65211, United States
| | - Jayakanth Kankanala
- Center for Drug Design, Academic Health Center, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Jiashu Xie
- Center for Drug Design, Academic Health Center, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Stefan G Sarafianos
- Department of Molecular Microbiology and Immunology and Department of Biochemistry, Christopher S. Bond Life Sciences Center, University of Missouri , Columbia, Missouri 65211, United States
| | - Zhengqiang Wang
- Center for Drug Design, Academic Health Center, University of Minnesota , Minneapolis, Minnesota 55455, United States
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27
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Michailidis E, Huber AD, Ryan EM, Ong YT, Leslie MD, Matzek KB, Singh K, Marchand B, Hagedorn AN, Kirby KA, Rohan LC, Kodama EN, Mitsuya H, Parniak MA, Sarafianos SG. 4'-Ethynyl-2-fluoro-2'-deoxyadenosine (EFdA) inhibits HIV-1 reverse transcriptase with multiple mechanisms. J Biol Chem 2014; 289:24533-48. [PMID: 24970894 DOI: 10.1074/jbc.m114.562694] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
4'-Ethynyl-2-fluoro-2'-deoxyadenosine (EFdA) is a nucleoside analog that, unlike approved anti-human immunodeficiency virus type 1 (HIV-1) nucleoside reverse transcriptase inhibitors, has a 3'-OH and exhibits remarkable potency against wild-type and drug-resistant HIVs. EFdA triphosphate (EFdA-TP) is unique among nucleoside reverse transcriptase inhibitors because it inhibits HIV-1 reverse transcriptase (RT) with multiple mechanisms. (a) EFdA-TP can block RT as a translocation-defective RT inhibitor that dramatically slows DNA synthesis, acting as a de facto immediate chain terminator. Although non-translocated EFdA-MP-terminated primers can be unblocked, they can be efficiently converted back to the EFdA-MP-terminated form. (b) EFdA-TP can function as a delayed chain terminator, allowing incorporation of an additional dNTP before blocking DNA synthesis. In such cases, EFdA-MP-terminated primers are protected from excision. (c) EFdA-MP can be efficiently misincorporated by RT, leading to mismatched primers that are extremely hard to extend and are also protected from excision. The context of template sequence defines the relative contribution of each mechanism and affects the affinity of EFdA-MP for potential incorporation sites, explaining in part the lack of antagonism between EFdA and tenofovir. Changes in the type of nucleotide before EFdA-MP incorporation can alter its mechanism of inhibition from delayed chain terminator to immediate chain terminator. The versatility of EFdA in inhibiting HIV replication by multiple mechanisms may explain why resistance to EFdA is more difficult to emerge.
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Affiliation(s)
- Eleftherios Michailidis
- From the Christopher Bond Life Sciences Center and Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, Missouri 65211
| | - Andrew D Huber
- From the Christopher Bond Life Sciences Center and Departments of Veterinary Pathobiology and
| | - Emily M Ryan
- From the Christopher Bond Life Sciences Center and Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, Missouri 65211
| | - Yee T Ong
- From the Christopher Bond Life Sciences Center and Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, Missouri 65211
| | - Maxwell D Leslie
- From the Christopher Bond Life Sciences Center and Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, Missouri 65211
| | - Kayla B Matzek
- From the Christopher Bond Life Sciences Center and Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, Missouri 65211
| | - Kamalendra Singh
- From the Christopher Bond Life Sciences Center and Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, Missouri 65211
| | - Bruno Marchand
- From the Christopher Bond Life Sciences Center and Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, Missouri 65211
| | - Ariel N Hagedorn
- From the Christopher Bond Life Sciences Center and Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, Missouri 65211
| | - Karen A Kirby
- From the Christopher Bond Life Sciences Center and Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, Missouri 65211
| | - Lisa C Rohan
- Magee-Womens Research Institute and Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania 15213
| | - Eiichi N Kodama
- Division of Emerging Infectious Diseases, Tohoku University, Sendai 980-8575, Japan
| | - Hiroaki Mitsuya
- Department of Internal Medicine, Kumamoto University, Kumamoto 860-8556, Japan, Experimental Retrovirology Section, HIV/AIDS Malignancy Branch, National Institutes of Health, Bethesda, Maryland 20892, and
| | - Michael A Parniak
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15219
| | - Stefan G Sarafianos
- From the Christopher Bond Life Sciences Center and Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, Missouri 65211, Biochemistry, University of Missouri, Columbia, Missouri 65211,
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Michailidis E, Ryan EM, Hachiya A, Kirby KA, Marchand B, Leslie MD, Huber AD, Ong YT, Jackson JC, Singh K, Kodama EN, Mitsuya H, Parniak MA, Sarafianos SG. Hypersusceptibility mechanism of Tenofovir-resistant HIV to EFdA. Retrovirology 2013; 10:65. [PMID: 23800377 PMCID: PMC3695782 DOI: 10.1186/1742-4690-10-65] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 06/13/2013] [Indexed: 11/28/2022] Open
Abstract
Background The K65R substitution in human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) is the major resistance mutation selected in patients treated with first-line antiretroviral tenofovir disoproxil fumarate (TDF). 4'-ethynyl-2-fluoro-2'-deoxyadenosine (EFdA), is the most potent nucleoside analog RT inhibitor (NRTI) that unlike all approved NRTIs retains a 3'-hydroxyl group and has remarkable potency against wild-type (WT) and drug-resistant HIVs. EFdA acts primarily as a chain terminator by blocking translocation following its incorporation into the nascent DNA chain. EFdA is in preclinical development and its effect on clinically relevant drug resistant HIV strains is critically important for the design of optimal regimens prior to initiation of clinical trials. Results Here we report that the K65R RT mutation causes hypersusceptibility to EFdA. Specifically, in single replication cycle experiments we found that EFdA blocks WT HIV ten times more efficiently than TDF. Under the same conditions K65R HIV was inhibited over 70 times more efficiently by EFdA than TDF. We determined the molecular mechanism of this hypersensitivity using enzymatic studies with WT and K65R RT. This substitution causes minor changes in the efficiency of EFdA incorporation with respect to the natural dATP substrate and also in the efficiency of RT translocation following incorporation of the inhibitor into the nascent DNA. However, a significant decrease in the excision efficiency of EFdA-MP from the 3’ primer terminus appears to be the primary cause of increased susceptibility to the inhibitor. Notably, the effects of the mutation are DNA-sequence dependent. Conclusion We have elucidated the mechanism of K65R HIV hypersusceptibility to EFdA. Our findings highlight the potential of EFdA to improve combination strategies against TDF-resistant HIV-1 strains.
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Affiliation(s)
- Eleftherios Michailidis
- Christopher Bond Life Sciences Center, Department of Molecular Microbiology & Immunology, University of Missouri, Columbia, MO 65211, USA
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