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Yiu B, Robbins N, Cowen LE. Interdisciplinary approaches for the discovery of novel antifungals. Trends Mol Med 2024:S1471-4914(24)00121-7. [PMID: 38777733 DOI: 10.1016/j.molmed.2024.04.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 04/10/2024] [Accepted: 04/26/2024] [Indexed: 05/25/2024]
Abstract
Pathogenic fungi are an increasing public health concern. The emergence of antifungal resistance coupled with the scarce antifungal arsenal highlights the need for novel therapeutics. Fortunately, the past few years have witnessed breakthroughs in antifungal development. Here, we discuss pivotal interdisciplinary approaches for the discovery of novel compounds with efficacy against diverse fungal pathogens. We highlight breakthroughs in improving current antifungal scaffolds, as well as the utility of compound combinations to extend the lifespan of antifungals. Finally, we describe efforts to refine candidate chemical scaffolds by leveraging structure-guided approaches, and the use of functional genomics to expand our knowledge of druggable antifungal targets. Overall, we emphasize the importance of interdisciplinary collaborations in the endeavor to develop innovative antifungal strategies.
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Affiliation(s)
- Bonnie Yiu
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, M5G 1M1, Canada
| | - Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, M5G 1M1, Canada
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, M5G 1M1, Canada.
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2
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Kohlmann P, Krylov SN, Marchand P, Jose J. FRET Assays for the Identification of C. albicans HSP90-Sba1 and Human HSP90α-p23 Binding Inhibitors. Pharmaceuticals (Basel) 2024; 17:516. [PMID: 38675476 PMCID: PMC11053944 DOI: 10.3390/ph17040516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2024] [Revised: 04/11/2024] [Accepted: 04/12/2024] [Indexed: 04/28/2024] Open
Abstract
Heat shock protein 90 (HSP90) is a critical target for anticancer and anti-fungal-infection therapies due to its central role as a molecular chaperone involved in protein folding and activation. In this study, we developed in vitro Förster Resonance Energy Transfer (FRET) assays to characterize the binding of C. albicans HSP90 to its co-chaperone Sba1, as well as that of the homologous human HSP90α to p23. The assay for human HSP90α binding to p23 enables selectivity assessment for compounds aimed to inhibit the binding of C. albicans HSP90 to Sba1 without affecting the physiological activity of human HSP90α. The combination of the two assays is important for antifungal drug development, while the assay for human HSP90α can potentially be used on its own for anticancer drug discovery. Since ATP binding of HSP90 is a prerequisite for HSP90-Sba1/p23 binding, ATP-competitive inhibitors can be identified with the assays. The specificity of binding of fusion protein constructs-HSP90-mNeonGreen (donor) and Sba1-mScarlet-I (acceptor)-to each other in our assay was confirmed via competitive inhibition by both non-labeled Sba1 and known ATP-competitive inhibitors. We utilized the developed assays to characterize the stability of both HSP90-Sba1 and HSP90α-p23 affinity complexes quantitatively. Kd values were determined and assessed for their precision and accuracy using the 95.5% confidence level. For HSP90-Sba1, the precision confidence interval (PCI) was found to be 70-120 (100 ± 20) nM while the accuracy confidence interval (ACI) was 100-130 nM. For HSP90α-p23, PCI was 180-260 (220 ± 40) nM and ACI was 200-270 nM. The developed assays were used to screen a nucleoside-mimetics library of 320 compounds for inhibitory activity against both C. albicans HSP90-Sba1 and human HSP90α-p23 binding. No novel active compounds were identified. Overall, the developed assays exhibited low data variability and robust signal separation, achieving Z factors > 0.5.
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Affiliation(s)
- Philip Kohlmann
- Institute of Pharmaceutical and Medicinal Chemistry, Pharmacampus, University of Münster, 48149 Münster, Germany;
| | - Sergey N. Krylov
- Department of Chemistry, York University, Toronto, ON M3J 1P3, Canada;
- Centre for Research on Biomolecular Interactions, York University, Toronto, ON M3J 1P3, Canada
| | - Pascal Marchand
- Cibles et Médicaments des Infections et de l’Immunité, IICiMed, Nantes Université, UR 1155, F-44000 Nantes, France;
| | - Joachim Jose
- Institute of Pharmaceutical and Medicinal Chemistry, Pharmacampus, University of Münster, 48149 Münster, Germany;
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3
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Puumala E, Fallah S, Robbins N, Cowen LE. Advancements and challenges in antifungal therapeutic development. Clin Microbiol Rev 2024; 37:e0014223. [PMID: 38294218 PMCID: PMC10938895 DOI: 10.1128/cmr.00142-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2024] Open
Abstract
Over recent decades, the global burden of fungal disease has expanded dramatically. It is estimated that fungal disease kills approximately 1.5 million individuals annually; however, the true worldwide burden of fungal infection is thought to be higher due to existing gaps in diagnostics and clinical understanding of mycotic disease. The development of resistance to antifungals across diverse pathogenic fungal genera is an increasingly common and devastating phenomenon due to the dearth of available antifungal classes. These factors necessitate a coordinated response by researchers, clinicians, public health agencies, and the pharmaceutical industry to develop new antifungal strategies, as the burden of fungal disease continues to grow. This review provides a comprehensive overview of the new antifungal therapeutics currently in clinical trials, highlighting their spectra of activity and progress toward clinical implementation. We also profile up-and-coming intracellular proteins and pathways primed for the development of novel antifungals targeting their activity. Ultimately, we aim to emphasize the importance of increased investment into antifungal therapeutics in the current continually evolving landscape of infectious disease.
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Affiliation(s)
- Emily Puumala
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Sara Fallah
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Leah E. Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
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4
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Liu J, Shu H, Xia Q, You Q, Wang L. Recent developments of HSP90 inhibitors: an updated patent review (2020-present). Expert Opin Ther Pat 2024; 34:1-15. [PMID: 38441084 DOI: 10.1080/13543776.2024.2327295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 03/01/2024] [Indexed: 03/09/2024]
Abstract
INTRODUCTION The 90-kDa heat shock protein (HSP90) functions as a molecular chaperone, it assumes a significant role in diseases such as cancer, inflammation, neurodegeneration, and infection. Therefore, the research and development of HSP90 inhibitors have garnered considerable attention. AREAS COVERED The primary references source for this review is patents obtained from SciFinder, encompassing patents on HSP90 inhibitors from the period of 2020 to 2023.This review includes a thorough analysis of their structural attributes, pharmacological properties, and potential clinical utilities. EXPERT OPINION In the past few years, HSP90 inhibitors targeting ATP binding pocket are still predominate and one of them has been launched, besides, novel drug design strategies like C-terminal targeting, isoform selective inhibiting and bifunctional molecules are booming, aiming to improve the efficacy and safety. With expanded drug types and applications, HSP90 inhibitors may gradually becoming a sagacious option for treating various diseases.
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Affiliation(s)
- Jianfeng Liu
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing, China
- Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Huangliang Shu
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing, China
- Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Qinxin Xia
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing, China
- Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Qidong You
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing, China
- Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Lei Wang
- State Key Laboratory of Natural Medicines and Jiangsu Key Laboratory of Drug Design and Optimization, China Pharmaceutical University, Nanjing, China
- Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, China
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5
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Efremenko E, Aslanli A, Stepanov N, Senko O, Maslova O. Various Biomimetics, Including Peptides as Antifungals. Biomimetics (Basel) 2023; 8:513. [PMID: 37999154 PMCID: PMC10669293 DOI: 10.3390/biomimetics8070513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 09/20/2023] [Accepted: 10/26/2023] [Indexed: 11/25/2023] Open
Abstract
Biomimetics, which are similar to natural compounds that play an important role in the metabolism, manifestation of functional activity and reproduction of various fungi, have a pronounced attraction in the current search for new effective antifungals. Actual trends in the development of this area of research indicate that unnatural amino acids can be used as such biomimetics, including those containing halogen atoms; compounds similar to nitrogenous bases embedded in the nucleic acids synthesized by fungi; peptides imitating fungal analogs; molecules similar to natural substrates of numerous fungal enzymes and quorum-sensing signaling molecules of fungi and yeast, etc. Most parts of this review are devoted to the analysis of semi-synthetic and synthetic antifungal peptides and their targets of action. This review is aimed at combining and systematizing the current scientific information accumulating in this area of research, developing various antifungals with an assessment of the effectiveness of the created biomimetics and the possibility of combining them with other antimicrobial substances to reduce cell resistance and improve antifungal effects.
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Affiliation(s)
- Elena Efremenko
- Faculty of Chemistry, Lomonosov Moscow State University, Lenin Hills 1/3, Moscow 119991, Russia
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6
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Robbins N, Cowen LE. Roles of Hsp90 in Candida albicans morphogenesis and virulence. Curr Opin Microbiol 2023; 75:102351. [PMID: 37399670 PMCID: PMC11016340 DOI: 10.1016/j.mib.2023.102351] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 06/02/2023] [Accepted: 06/04/2023] [Indexed: 07/05/2023]
Abstract
Hsp90 is a conserved molecular chaperone that facilitates the folding and function of hundreds of client proteins, many of which serve as core hubs of signal transduction networks. Hsp90 has a critical role in virulence of the opportunistic fungal pathogen Candida albicans, which exists as a natural commensal of the human microbiota and is a leading cause of invasive fungal infections, particularly in immunocompromised individuals. The ability of C. albicans to cause disease is tightly coupled to its capacity to undergo a morphogenetic transition between yeast and filamentous forms. Here, we describe the complex mechanisms by which Hsp90 regulates C. albicans morphogenesis and virulence, and explore the potential of targeting fungal Hsp90 as a therapeutic strategy to combat fungal infections.
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Affiliation(s)
- Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada.
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Lu H, Hong T, Jiang Y, Whiteway M, Zhang S. Candidiasis: From cutaneous to systemic, new perspectives of potential targets and therapeutic strategies. Adv Drug Deliv Rev 2023; 199:114960. [PMID: 37307922 DOI: 10.1016/j.addr.2023.114960] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 06/05/2023] [Accepted: 06/07/2023] [Indexed: 06/14/2023]
Abstract
Candidiasis is an infection caused by fungi from a Candida species, most commonly Candida albicans. C. albicans is an opportunistic fungal pathogen typically residing on human skin and mucous membranes of the mouth, intestines or vagina. It can cause a wide variety of mucocutaneous barrier and systemic infections; and becomes a severe health problem in HIV/AIDS patients and in individuals who are immunocompromised following chemotherapy, treatment with immunosuppressive agents or after antibiotic-induced dysbiosis. However, the immune mechanism of host resistance to C. albicans infection is not fully understood, there are a limited number of therapeutic antifungal drugs for candidiasis, and these have disadvantages that limit their clinical application. Therefore, it is urgent to uncover the immune mechanisms of the host protecting against candidiasis and to develop new antifungal strategies. This review synthesizes current knowledge of host immune defense mechanisms from cutaneous candidiasis to invasive C. albicans infection and documents promising insights for treating candidiasis through inhibitors of potential antifungal target proteins.
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Affiliation(s)
- Hui Lu
- Department of Pharmacology, Shanghai Tenth People's Hospital, Tongji University, School of Medicine, Shanghai, China
| | - Ting Hong
- Department of Anesthesiology, Huadong Hospital Affiliated to Fudan University, Shanghai, China
| | - Yuanying Jiang
- Department of Pharmacology, Shanghai Tenth People's Hospital, Tongji University, School of Medicine, Shanghai, China
| | - Malcolm Whiteway
- Department of Biology, Concordia University, Montreal, QC, Canada.
| | - Shiqun Zhang
- Department of Pharmacology, Shanghai Tenth People's Hospital, Tongji University, School of Medicine, Shanghai, China.
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8
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Qi JD, Meng YQ, Sun J, Li WX, Zhai HX, Zhang C, Quan J, Jin CH. Synthesis and antimicrobial activity evaluation of pyrazole derivatives containing the imidazo[2,1-b][1,3,4]thiadiazole moiety. Arch Pharm (Weinheim) 2023:e2300110. [PMID: 37328442 DOI: 10.1002/ardp.202300110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 05/27/2023] [Accepted: 05/30/2023] [Indexed: 06/18/2023]
Abstract
Four series of novel pyrazole derivatives (compounds 17a-m, 18a-m, 19a-g, and 20a-g) were synthesized, and their antibacterial and antifungal activities were evaluated. Most of the target compounds (17a-m, 18k-m, and 19b-g) showed strong antifungal activity and high selectivity relative to both Gram-positive and Gram-negative bacteria. Among them, compounds 17l (minimum inhibitory concentration [MIC] = 0.25 µg/mL) and 17m (MIC = 0.25 µg/mL) showed the strongest antifungal activity, being 2- and 4-fold more active than the positive controls gatifloxacin and fluconazole, respectively. In particular, compound 17l showed little cytotoxicity against human LO2 cells and did not exhibit hemolysis at ultrahigh concentrations, as did the positive control compounds gatifloxacin and fluconazole. These results indicate that these compounds are valuable for further development as antifungal agents.
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Affiliation(s)
- Jun-Da Qi
- Key Laboratory of Natural Medicines of the Changbai Mountain, Ministry of Education, College of Pharmacy, Yanbian University, Yanji, China
| | - Yu-Qing Meng
- Interdisciplinary Program of Biological Function Molecules, College of Integration Science, Yanbian University, Yanji, China
| | - Jingxin Sun
- Key Laboratory of Natural Medicines of the Changbai Mountain, Ministry of Education, College of Pharmacy, Yanbian University, Yanji, China
| | - Wan-Xin Li
- Key Laboratory of Natural Medicines of the Changbai Mountain, Ministry of Education, College of Pharmacy, Yanbian University, Yanji, China
| | - Hou-Xiang Zhai
- Key Laboratory of Natural Medicines of the Changbai Mountain, Ministry of Education, College of Pharmacy, Yanbian University, Yanji, China
| | - Changhao Zhang
- Key Laboratory of Natural Medicines of the Changbai Mountain, Ministry of Education, College of Pharmacy, Yanbian University, Yanji, China
| | - Jishan Quan
- Key Laboratory of Natural Medicines of the Changbai Mountain, Ministry of Education, College of Pharmacy, Yanbian University, Yanji, China
- Interdisciplinary Program of Biological Function Molecules, College of Integration Science, Yanbian University, Yanji, China
| | - Cheng-Hua Jin
- Key Laboratory of Natural Medicines of the Changbai Mountain, Ministry of Education, College of Pharmacy, Yanbian University, Yanji, China
- Interdisciplinary Program of Biological Function Molecules, College of Integration Science, Yanbian University, Yanji, China
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9
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Zhu P, Li Y, Guo T, Liu S, Tancer RJ, Hu C, Zhao C, Xue C, Liao G. New antifungal strategies: drug combination and co-delivery. Adv Drug Deliv Rev 2023; 198:114874. [PMID: 37211279 DOI: 10.1016/j.addr.2023.114874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Revised: 05/12/2023] [Accepted: 05/14/2023] [Indexed: 05/23/2023]
Abstract
The growing occurrence of invasive fungal infections and the mounting rates of drug resistance constitute a significant menace to human health. Antifungal drug combinations have garnered substantial interest for their potential to improve therapeutic efficacy, reduce drug doses, reverse, or ameliorate drug resistance. A thorough understanding of the molecular mechanisms underlying antifungal drug resistance and drug combination is key to developing new drug combinations. Here we discuss the mechanisms of antifungal drug resistance and elucidate how to discover potent drug combinations to surmount resistance. We also examine the challenges encountered in developing such combinations and discuss prospects, including advanced drug delivery strategies.
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Affiliation(s)
- Ping Zhu
- State Key Laboratory of Silkworm Genome Biology, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400700, China
| | - Yan Li
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100050, China
| | - Ting Guo
- State Key Laboratory of Silkworm Genome Biology, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400700, China
| | - Simei Liu
- Department of Traditional Chinese Medicine, Chongqing College of Traditional Chinese Medicine, Chongqing 402760, China; Institute of Pharmacology and Toxicology, Chongqing Academy of Chinese Materia Medica, Chongqing 400065, China
| | - Robert J Tancer
- Public Health Research Institute and Department of Microbiology, Biochemistry and Molecular Genetics, New Jersey Medical School, Rutgers University, Newark, NJ, 07103, USA
| | - Changhua Hu
- State Key Laboratory of Silkworm Genome Biology, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400700, China
| | - Chengzhi Zhao
- Chongqing Health Center for Women and Children, Chongqing, 400700, PR China.
| | - Chaoyang Xue
- Public Health Research Institute and Department of Microbiology, Biochemistry and Molecular Genetics, New Jersey Medical School, Rutgers University, Newark, NJ, 07103, USA
| | - Guojian Liao
- State Key Laboratory of Silkworm Genome Biology, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400700, China.
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10
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Liu N, Tu J, Huang Y, Yang W, Wang Q, Li Z, Sheng C. Target- and prodrug-based design for fungal diseases and cancer-associated fungal infections. Adv Drug Deliv Rev 2023; 197:114819. [PMID: 37024014 DOI: 10.1016/j.addr.2023.114819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/28/2023] [Accepted: 03/31/2023] [Indexed: 04/07/2023]
Abstract
Invasive fungal infections (IFIs) are emerging as a serious threat to public health and are associated with high incidence and mortality. IFIs also represent a frequent complication in patients with cancer who are undergoing chemotherapy. However, effective and safe antifungal agents remain limited, and the development of severe drug resistance further undermines the efficacy of antifungal therapy. Therefore, there is an urgent need for novel antifungal agents to treat life-threatening fungal diseases, especially those with new mode of action, favorable pharmacokinetic profiles, and anti-resistance activity. In this review, we summarize new antifungal targets and target-based inhibitor design, with a focus on their antifungal activity, selectivity, and mechanism. We also illustrate the prodrug design strategy used to improve the physicochemical and pharmacokinetic profiles of antifungal agents. Dual-targeting antifungal agents offer a new strategy for the treatment of resistant infections and cancer-associated fungal infections.
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11
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Lee Y, Hossain S, MacAlpine J, Robbins N, Cowen LE. Functional genomic analysis of Candida albicans protein kinases reveals modulators of morphogenesis in diverse environments. iScience 2023; 26:106145. [PMID: 36879823 PMCID: PMC9984565 DOI: 10.1016/j.isci.2023.106145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 12/21/2022] [Accepted: 02/01/2023] [Indexed: 02/05/2023] Open
Abstract
Candida albicans is a leading cause of mycotic infection. The ability to transition between yeast and filamentous forms is critical to C. albicans virulence and complex signaling pathways regulate this process. Here, we screened a C. albicans protein kinase mutant library in six environmental conditions to identify regulators of morphogenesis. We identified the uncharacterized gene orf19.3751 as a negative regulator of filamentation and follow-up investigations implicated a role for orf19.3751 in cell cycle regulation. We also uncovered a dual role for the kinases Ire1 and protein kinase A (Tpk1 and Tpk2) in C. albicans morphogenesis, specifically as negative regulators of wrinkly colony formation on solid medium but positive regulators of filamentation in liquid medium. Further analyses suggested Ire1 modulates morphogenesis in both media states in part through the transcription factor Hac1 and in part through independent mechanisms. Overall, this work provides insights into the signaling governing morphogenesis in C. albicans.
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Affiliation(s)
- Yunjin Lee
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Saif Hossain
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Jessie MacAlpine
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
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A Small Molecule Inhibitor of Erg251 Makes Fluconazole Fungicidal by Inhibiting the Synthesis of the 14α-Methylsterols. mBio 2023; 14:e0263922. [PMID: 36475771 PMCID: PMC9973333 DOI: 10.1128/mbio.02639-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Fluconazole (FLC) is widely used to prevent and treat invasive fungal infections. However, FLC is a fungistatic agent, allowing clinical FLC-susceptible isolates to tolerate FLC. Making FLC fungicidal in combination with adjuvants is a promising strategy to avoid FLC resistance and eliminate the persistence and recurrence of fungal infections. Here, we identify a new small molecule compound, CZ66, that can make FLC fungicidal. The mechanism of action of CZ66 is targeting the C-4 sterol methyl oxidase, encoded by the ERG251 gene, resulting in decreased content of sterols with the 14α-methyl group and ultimately eliminating FLC tolerance of Candida albicans. CZ66 most likely interacts with Erg251 through residues Glu195, Gly206, and Arg241. Establishing Erg251 as a synergistic lethal target protein of FLC should direct research to identify specific small molecule inhibitors of 14α-methylsterol synthesis and open the way to abolishing fungal FLC tolerance. IMPORTANCE Fluconazole (FLC) tolerance increases the frequency of acquired FLC resistance, and a high FLC tolerance level is associated with persistent candidemia. Multiple functional proteins, such as calcineurin, heat shock protein 90 (Hsp90), and ADP ribosylation factor, are essential for the survival of C. albicans exposed to FLC, but how these factors increase the fungicidal activity of FLC remains to be determined. In this study, we found that 14α-methylsterols replace ergosterol to allow C. albicans to survive FLC, but Erg251 inactivated by CZ66 results in loss of 14α-methylsterol synthesis and cell death of C. albicans treated with FLC. Establishing Erg251 as a synergistic lethal target protein of FLC should direct research to identify specific small molecule inhibitors of 14α-methylsterol synthesis and open the way to abolishing fungal FLC tolerance.
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13
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Deng H, Song J, Huang Y, Yang C, Zang X, Zhou Y, Li H, Dai B, Xue X. Combating increased antifungal drug resistance in Cryptococcus, what should we do in the future? Acta Biochim Biophys Sin (Shanghai) 2023; 55:540-547. [PMID: 36815374 DOI: 10.3724/abbs.2023011] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Few therapeutic drugs and increased drug resistance have aggravated the current treatment difficulties of Cryptococcus in recent years. To better understand the antifungal drug resistance mechanism and treatment strategy of cryptococcosis. In this review, by combining the fundamental features of Cryptococcus reproduction leading to changes in its genome, we review recent research into the mechanism of four current anti-cryptococcal agents, coupled with new therapeutic strategies and the application of advanced technologies WGS and CRISPR-Cas9 in this field, hoping to provide a broad idea for the future clinical therapy of cryptococcosis.
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Affiliation(s)
- Hengyu Deng
- Affiliated Hospital of Weifang Medical University, School of Clinical Medicine, Weifang Medical University, Weifang 261053, China
| | - Jialin Song
- Affiliated Hospital of Weifang Medical University, School of Clinical Medicine, Weifang Medical University, Weifang 261053, China
| | - Yemei Huang
- Department of Respiratory and Critical Care, Beijing Shijitan Hospital, Capital Medical University; Peking University Ninth School of Clinical Medicine, Beijing 100089, China
| | - Chen Yang
- Department of Laboratory Medicine, the First Medical Centre, Chinese PLA General Hospital, Beijing 100853, China
| | - Xuelei Zang
- Department of Respiratory and Critical Care, Beijing Shijitan Hospital, Capital Medical University; Peking University Ninth School of Clinical Medicine, Beijing 100089, China
| | - Yangyu Zhou
- Department of Respiratory and Critical Care, Beijing Shijitan Hospital, Capital Medical University; Peking University Ninth School of Clinical Medicine, Beijing 100089, China
| | - Hongli Li
- Affiliated Hospital of Weifang Medical University, School of Clinical Medicine, Weifang Medical University, Weifang 261053, China
| | - Bin Dai
- Department of Respiratory and Critical Care, Beijing Shijitan Hospital, Capital Medical University; Peking University Ninth School of Clinical Medicine, Beijing 100089, China
| | - Xinying Xue
- Affiliated Hospital of Weifang Medical University, School of Clinical Medicine, Weifang Medical University, Weifang 261053, China.,Department of Respiratory and Critical Care, Beijing Shijitan Hospital, Capital Medical University; Peking University Ninth School of Clinical Medicine, Beijing 100089, China
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14
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Hoy MJ, Heitman J. Drug Target Elucidation Through Isolation and Analysis of Drug-Resistant Mutants in Cryptococcus neoformans. Methods Mol Biol 2023; 2658:127-143. [PMID: 37024699 PMCID: PMC10602406 DOI: 10.1007/978-1-0716-3155-3_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
Abstract
Drug target identification is an essential component to antifungal drug development. Many methods, including large chemical library screening, natural product screening, and drug repurposing efforts, can identify compounds with favorable in vitro antifungal activity. However, these approaches will often identify compounds with no known mechanism of action. Herein, we describe a method utilizing the human fungal pathogen Cryptococcus neoformans to identify antifungal drug targets through the isolation of spontaneous resistant mutants, antifungal testing, whole-genome sequencing, and variant analysis.
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Affiliation(s)
- Michael J Hoy
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, USA
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, USA.
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15
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Jeon JH, Im S, Kim HS, Lee D, Jeong K, Ku JM, Nam TG. Chemical Chaperones to Inhibit Endoplasmic Reticulum Stress: Implications in Diseases. Drug Des Devel Ther 2022; 16:4385-4397. [PMID: 36583112 PMCID: PMC9793730 DOI: 10.2147/dddt.s393816] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 12/10/2022] [Indexed: 12/24/2022] Open
Abstract
The endoplasmic reticulum (ER) is responsible for structural transformation or folding of de novo proteins for transport to the Golgi. When the folding capacity of the ER is exceeded or excessive accumulation of misfolded proteins occurs, the ER enters a stressed condition (ER stress) and unfolded protein responses (UPR) are triggered in order to rescue cells from the stress. Recovery of ER proceeds toward either survival or cell apoptosis. ER stress is implicated in many pathologies, such as diabetes, cardiovascular diseases, inflammatory diseases, neurodegeneration, and lysosomal storage diseases. As a survival or adaptation mechanism, chaperone molecules are upregulated to manage ER stress. Chemical versions of chaperone have been developed in search of drug candidates for ER stress-related diseases. In this review, synthetic or semi-synthetic chemical chaperones are categorized according to potential therapeutic area and listed along with their chemical structure and activity. Although only a few chemical chaperones have been approved as pharmaceutical drugs, a dramatic increase in literatures over the recent decades indicates enormous amount of efforts paid by many researchers. The efforts warrant clearer understanding of ER stress and the related diseases and consequently will offer a promising drug discovery platform with chaperone activity.
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Affiliation(s)
- Jae-Ho Jeon
- Department of Pharmacy and Institute of Pharmaceutical Science and Technology, Hanyang University ERICA campus, Ansan, Gyeonggi-do, 15588, Republic of Korea
| | - Somyoung Im
- Department of Pharmacy and Institute of Pharmaceutical Science and Technology, Hanyang University ERICA campus, Ansan, Gyeonggi-do, 15588, Republic of Korea
| | - Hyo Shin Kim
- Department of Pharmacy and Institute of Pharmaceutical Science and Technology, Hanyang University ERICA campus, Ansan, Gyeonggi-do, 15588, Republic of Korea
| | - Dongyun Lee
- Department of Pharmacy and Institute of Pharmaceutical Science and Technology, Hanyang University ERICA campus, Ansan, Gyeonggi-do, 15588, Republic of Korea
| | - Kwiwan Jeong
- Gyeonggi Bio-Center, Gyeonggido Business and Science Accelerator, Suwon, Gyeonggi-do, 16229, Republic of Korea
| | - Jin-Mo Ku
- Gyeonggi Bio-Center, Gyeonggido Business and Science Accelerator, Suwon, Gyeonggi-do, 16229, Republic of Korea
| | - Tae-Gyu Nam
- Department of Pharmacy and Institute of Pharmaceutical Science and Technology, Hanyang University ERICA campus, Ansan, Gyeonggi-do, 15588, Republic of Korea,Correspondence: Tae-Gyu Nam, Tel +82-31-400-5807, Fax +82-31-400-5958, Email
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16
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Choudhary M, Kumar V, Naik B, Verma A, Saris PEJ, Kumar V, Gupta S. Antifungal metabolites, their novel sources, and targets to combat drug resistance. Front Microbiol 2022; 13:1061603. [PMID: 36532457 PMCID: PMC9755354 DOI: 10.3389/fmicb.2022.1061603] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 11/08/2022] [Indexed: 09/29/2023] Open
Abstract
Excessive antibiotic prescriptions as well as their misuse in agriculture are the main causes of antimicrobial resistance which poses a growing threat to public health. It necessitates the search for novel chemicals to combat drug resistance. Since ancient times, naturally occurring medicines have been employed and the enormous variety of bioactive chemicals found in nature has long served as an inspiration for researchers looking for possible therapeutics. Secondary metabolites from microorganisms, particularly those from actinomycetes, have made it incredibly easy to find new molecules. Different actinomycetes species account for more than 70% of naturally generated antibiotics currently used in medicine, and they also produce a variety of secondary metabolites, including pigments, enzymes, and anti-inflammatory compounds. They continue to be a crucial source of fresh chemical diversity and a crucial component of drug discovery. This review summarizes some uncommon sources of antifungal metabolites and highlights the importance of further research on these unusual habitats as a source of novel antimicrobial molecules.
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Affiliation(s)
- Megha Choudhary
- Himalayan School of Biosciences, Swami Rama Himalayan University, Dehradun, India
| | - Vijay Kumar
- Himalayan School of Biosciences, Swami Rama Himalayan University, Dehradun, India
| | - Bindu Naik
- Department of Life Sciences (Food Technology & Nutrition), Graphic Era (Deemed to be University), Dehradun, India
| | - Ankit Verma
- Himalayan School of Biosciences, Swami Rama Himalayan University, Dehradun, India
| | - Per Erik Joakim Saris
- Department of Microbiology, Faculty of Agriculture and Forestry, University of Helsinki, Helsinki, Finland
| | - Vivek Kumar
- Himalayan School of Biosciences, Swami Rama Himalayan University, Dehradun, India
| | - Sanjay Gupta
- Himalayan School of Biosciences, Swami Rama Himalayan University, Dehradun, India
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17
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Yang M, Li C, Li Y, Cheng C, Shi M, Yin L, Xue H, Liu Y. Design, synthesis, biological evaluation and molecular docking study of 2,4-diarylimidazoles and 2,4-bis(benzyloxy)-5-arylpyrimidines as novel HSP90 N-terminal inhibitors. J Enzyme Inhib Med Chem 2022; 37:2551-2565. [PMID: 36120957 PMCID: PMC9518286 DOI: 10.1080/14756366.2022.2124407] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The molecular chaperone HSP90 plays an essential role in cancer occurrence and development. Therefore, it is an important target for the development of anticancer drugs. 1,3-Dibenzyl-2-aryl imidazolidine (8) is a previously reported inhibitor of HSP90; however, its anticancer activity is poor. In this work, chemical modification of 8 led to the discovery of 2,4-diarylimidazoles and 2,4-bis(benzyloxy)-5-arylpyrimidines as two types of novel HSP90 N-terminal inhibitors. 16l and 22k exhibited antiproliferative activity against multiple breast cancer cell lines with IC50 values at the low micromolar level. 16l and 22k induced significant degradation of the client proteins AKT and ERK and a lower level of the heat shock response in comparison with tanespimycin (17-AAG). 22k exhibited a strong affinity for the HSP90α N-terminus with an IC50 value of 0.21 μM. A molecular docking study revealed that 16l and 22k successfully bind to the geldanamycin binding site at the N-terminus of HSP90α.
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Affiliation(s)
- Man Yang
- School of Life and Pharmaceutical Sciences, Dalian University of Technology, Panjin, China
| | - Chenyao Li
- School of Life and Pharmaceutical Sciences, Dalian University of Technology, Panjin, China
| | - Yajing Li
- School of Life and Pharmaceutical Sciences, Dalian University of Technology, Panjin, China
| | - Chen Cheng
- School of Life and Pharmaceutical Sciences, Dalian University of Technology, Panjin, China
| | - Meiyun Shi
- School of Life and Pharmaceutical Sciences, Dalian University of Technology, Panjin, China
| | - Lei Yin
- School of Life and Pharmaceutical Sciences, Dalian University of Technology, Panjin, China
| | - Hongyu Xue
- School of Life and Pharmaceutical Sciences, Dalian University of Technology, Panjin, China
| | - Yajun Liu
- School of Life and Pharmaceutical Sciences, Dalian University of Technology, Panjin, China
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18
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Robbins N, Cowen LE. Antifungal discovery. Curr Opin Microbiol 2022; 69:102198. [PMID: 36037637 PMCID: PMC10726697 DOI: 10.1016/j.mib.2022.102198] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 07/29/2022] [Accepted: 08/02/2022] [Indexed: 11/30/2022]
Abstract
Fungi have a profound impact on human health, leading to billions of infections and millions of deaths worldwide each year. Exacerbating the public health burden is the continued emergence of drug-resistant fungal pathogens coupled with a dearth of treatment options to combat serious infections. Despite this health threat, scientific advances in chemistry, genetics, and biochemistry methodologies have enabled novel antifungal compounds to be discovered. Here, we describe current approaches for the discovery and characterization of novel antifungals, focusing on the identification of novel chemical matter and elucidation of the cellular target of bioactive compounds, followed by a review of the most promising emerging therapies in the antifungal-development pipeline.
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Affiliation(s)
- Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.
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19
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Robbins N, Cowen LE. Genomic Approaches to Antifungal Drug Target Identification and Validation. Annu Rev Microbiol 2022; 76:369-388. [PMID: 35650665 PMCID: PMC10727914 DOI: 10.1146/annurev-micro-041020-094524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The last several decades have witnessed a surge in drug-resistant fungal infections that pose a serious threat to human health. While there is a limited arsenal of drugs that can be used to treat systemic infections, scientific advances have provided renewed optimism for the discovery of novel antifungals. The development of chemical-genomic assays using Saccharomyces cerevisiae has provided powerful methods to identify the mechanism of action of molecules in a living cell. Advances in molecular biology techniques have enabled complementary assays to be developed in fungal pathogens, including Candida albicans and Cryptococcus neoformans. These approaches enable the identification of target genes for drug candidates, as well as genes involved in buffering drug target pathways. Here, we examine yeast chemical-genomic assays and highlight how such resources can be utilized to predict the mechanisms of action of compounds, to study virulence attributes of diverse fungal pathogens, and to bolster the antifungal pipeline.
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Affiliation(s)
- Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada;
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada;
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20
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Cui X, Wang L, Lü Y, Yue C. Development and research progress of anti-drug resistant fungal drugs. J Infect Public Health 2022; 15:986-1000. [PMID: 35981408 DOI: 10.1016/j.jiph.2022.08.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 08/01/2022] [Accepted: 08/05/2022] [Indexed: 11/24/2022] Open
Abstract
With the widespread use of immunosuppressive agents and the increase in patients with severe infections, the incidence of fungal infections worldwide has increased year by year. The fungal pathogens Candida albicans, Cryptococcus neoformans and Aspergillus fumigatus cause a total of more than 1 million deaths each year. Long-term use of antifungal drugs can easily lead to fungal resistance, and the prevalence of drug-resistant fungi is a major global health challenge. In order to effectively control global fungal infections, there is an urgent need for new drugs that can exert effective antifungal activity and overcome drug resistance. We must promote the discovery of new antifungal targets and drugs, and find effective ways to control drug-resistant fungi through different ways, so as to reduce the threat of drug-resistant fungi to human life, health and safety. In the past few years, certain progress has been made in the research and development of antifungal drugs. In addition to summarizing some of the antifungal drugs currently approved by the FDA, this review also focuses on potential antifungal drugs, the repositioned drugs, and drugs that can treat drug-resistant bacteria and fungal infections, and provide new ideas for the development of antifungal drugs in the future.
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Affiliation(s)
- Xiangyi Cui
- Key Laboratory of Microbial Drugs Innovation and Transformation of Yan'an, School of Basic Medicine, Yan'an University, Yan'an 716000, Shaanxi, China; Shaanxi Engineering & Technological Research Center for Conversation & Utilization of Regional Biological Resources,Yan'an University, NO.580 Shengdi Road, Baota District, Yan'an 716000, Shaanxi, China.
| | - Lanlin Wang
- Key Laboratory of Microbial Drugs Innovation and Transformation of Yan'an, School of Basic Medicine, Yan'an University, Yan'an 716000, Shaanxi, China; Shaanxi Engineering & Technological Research Center for Conversation & Utilization of Regional Biological Resources,Yan'an University, NO.580 Shengdi Road, Baota District, Yan'an 716000, Shaanxi, China.
| | - Yuhong Lü
- Key Laboratory of Microbial Drugs Innovation and Transformation of Yan'an, School of Basic Medicine, Yan'an University, Yan'an 716000, Shaanxi, China; Shaanxi Engineering & Technological Research Center for Conversation & Utilization of Regional Biological Resources,Yan'an University, NO.580 Shengdi Road, Baota District, Yan'an 716000, Shaanxi, China.
| | - Changwu Yue
- Key Laboratory of Microbial Drugs Innovation and Transformation of Yan'an, School of Basic Medicine, Yan'an University, Yan'an 716000, Shaanxi, China; Shaanxi Engineering & Technological Research Center for Conversation & Utilization of Regional Biological Resources,Yan'an University, NO.580 Shengdi Road, Baota District, Yan'an 716000, Shaanxi, China.
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21
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Moghimi S, Shafiei M, Foroumadi A. Drug design strategies for the treatment azole-resistant candidiasis. Expert Opin Drug Discov 2022; 17:879-895. [PMID: 35793245 DOI: 10.1080/17460441.2022.2098949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
INTRODUCTION Despite the availability of novel antifungals and therapeutic strategies, the rate of global mortality linked to invasive fungal diseases from fungal infection remains high. Candida albicans account for the most invasive mycosis produced by yeast. Thus, the current arsenal of medicinal chemists is focused on finding new effective agents with lower toxicity and broad-spectrum activity. In this review article, recent efforts to find effective agents against azole-resistant candidiasis, a common fungal infection, are covered. AREAS COVERED Herein, the authors outlined all azole-based compounds, dual target, and new scaffolds (non-azole-based compounds) which were effective against azole-resistant candidiasis. In addition, the mechanism of action and SAR studies were also discussed, if the data were available. EXPERT OPINION The current status of fungal infections and the drawbacks of existing drugs have encouraged scientists to find novel scaffolds based on different methods like virtual screening and fragment-based drug discovery. Machine learning and in-silico methods have found their role in this field and experts are hopeful to find novel scaffolds/compounds by using these methods.
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Affiliation(s)
- Setareh Moghimi
- Drug Design and Development Research Center, The Institute of Pharmaceutical Sciences (TIPS), Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Shafiei
- Drug Design and Development Research Center, The Institute of Pharmaceutical Sciences (TIPS), Tehran University of Medical Sciences, Tehran, Iran.,Department of Medicinal Chemistry, Faculty of Pharmacy, Birjand University of Medical Sciences, Birjand, Iran
| | - Alireza Foroumadi
- Drug Design and Development Research Center, The Institute of Pharmaceutical Sciences (TIPS), Tehran University of Medical Sciences, Tehran, Iran.,Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
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22
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Design, synthesis, and biological evalution of bifunctional inhibitors against Hsp90-HDAC6 interplay. Eur J Med Chem 2022; 240:114582. [PMID: 35834905 DOI: 10.1016/j.ejmech.2022.114582] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 06/27/2022] [Accepted: 06/28/2022] [Indexed: 01/07/2023]
Abstract
HDAC6 and Hsp90, existing as a cytosolic complex play an important role in maintaining the protein homeostasis. The interplay of HDAC6 and Hsp90 has attracted wide attention due to their important role and promise as therapeutic targets in malignant cancers. Therefore, the discovery of dual inhibitors targeting HDAC6 and Hsp90 is of high importance. In the present study, we describe the design, synthesis, and biological evaluation of bifunctional inhibitors against HDAC6 and Hsp90 interplay. In particular, compound 6e shows a significant inhibitory activity against both HDAC6 and Hsp90 with IC50 values of 106 nM and 61 nM, respectively. Compound 6e promotes the acetylation of HDAC6 substrate proteins such as α-tubulin and Hsp90 via HDAC6 inhibition, and also induces the degradation of Hsp90 clients such as Her2, EGFR, Met, Akt, and HDAC6 via Hsp90 inhibition. Compound 6e consequently furnishes potent antiproliferative effect on gefitinib-resistant H1975 non-small cell lung cancer (NSCLC) with a GI50 value of 1.7 μM. In addition, compound 6e successfully achieved significant tumor growth inhibition in H1975 NSCLC xenograft model without noticeable abnormal behavior, body weight changes, and apparent ocular toxicity. We conclude that compound 6e constitutes an excellent tool as well as a valuable lead for assessment of Hsp90 and HDAC6 dual inhibition with a single molecule.
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23
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Zhen C, Lu H, Jiang Y. Novel Promising Antifungal Target Proteins for Conquering Invasive Fungal Infections. Front Microbiol 2022; 13:911322. [PMID: 35783432 PMCID: PMC9243655 DOI: 10.3389/fmicb.2022.911322] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Accepted: 05/24/2022] [Indexed: 11/26/2022] Open
Abstract
Invasive fungal infections (IFIs) pose a serious clinical problem, but the antifungal arsenal is limited and has many disadvantages, such as drug resistance and toxicity. Hence, there is an urgent need to develop antifungal compounds that target novel target proteins of pathogenic fungi for treating IFIs. This review provides a comprehensive summary of the biological functions of novel promising target proteins for treating IFIs in pathogenic fungi and their inhibitors. Inhibitors of inositol phosphoramide (IPC) synthases (such as Aureobasidin A, Khafrefungin, Galbonolide A, and Pleofungin A) have potent antifungal activities by inhibiting sphingolipid synthesis. Disrupting glycosylphosphatidylinositol (GPI) biosynthesis by Jawsamycin (an inhibitor of Spt14), M720 (an inhibitor of Mcd4), and APX001A (an inhibitor of Gwt1) is a promising strategy for treating IFIs. Turbinmicin is a natural-compound inhibitor of Sec14 and has extraordinary antifungal efficacy, broad-antifungal spectrum, low toxicity, and is a promising new compound for treating IFIs. CMLD013075 targets fungal heat shock protein 90 (Hsp90) and has remarkable antifungal efficacy. Olorofim, as an inhibitor of dihydrolactate dehydrogenase, is a breakthrough drug treatment for IFIs. These novel target proteins and their inhibitors may overcome the limitations of currently available antifungal drugs and improve patient outcomes in the treatment of IFIs.
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24
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Pan- and isoform-specific inhibition of Hsp90: Design strategy and recent advances. Eur J Med Chem 2022; 238:114516. [DOI: 10.1016/j.ejmech.2022.114516] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 06/01/2022] [Accepted: 06/02/2022] [Indexed: 12/11/2022]
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25
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Yin W, Wu T, Liu L, Jiang H, Zhang Y, Cui H, Sun Y, Qin Q, Sun Y, Gao Z, Zhao L, Su X, Zhao D, Cheng M. Species-Selective Targeting of Fungal Hsp90: Design, Synthesis, and Evaluation of Novel 4,5-Diarylisoxazole Derivatives for the Combination Treatment of Azole-Resistant Candidiasis. J Med Chem 2022; 65:5539-5564. [PMID: 35298171 DOI: 10.1021/acs.jmedchem.1c01991] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Invasive fungal infections are emerging as serious infectious diseases worldwide. Because of the development of antifungal drug resistance, the limited efficacy of the existing drugs has led to high mortality in patients. The use of the essential eukaryotic chaperone Hsp90, which plays a multifaceted role in drug resistance across diverse pathogenic fungal species, is considered to be a new strategy to mitigate the resistance and counter the threat posed by drug-resistant fungi. Thus, a series of 4,5-diarylisoxazole analogues as fungal Hsp90 inhibitors were designed and synthesized that had potent synergistic effects with fluconazole in vitro and in vivo. In particular, compound A17 could avoid the potential mammalian toxicity of Hsp90 inhibitors based on key reside differences between humans and fungi. These data support the feasibility of targeting fungal Hsp90 as a promising antifungal strategy and further development of compound A17 as a valuable research probe for the investigation of fungal Hsp90.
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Affiliation(s)
- Wenbo Yin
- Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Tianxiao Wu
- Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Lei Liu
- Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Hong Jiang
- Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Yuxin Zhang
- Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Hengxian Cui
- Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Yin Sun
- Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Qiaohua Qin
- Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Yixiang Sun
- Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Zixuan Gao
- Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Liyu Zhao
- Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Xin Su
- The School of Life Science and Biopharmaceutical, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Dongmei Zhao
- Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Maosheng Cheng
- Key Laboratory of Structure-Based Drug Design and Discovery, Ministry of Education, School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
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26
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Iyer KR, Robbins N, Cowen LE. The role of Candida albicans stress response pathways in antifungal tolerance and resistance. iScience 2022; 25:103953. [PMID: 35281744 PMCID: PMC8905312 DOI: 10.1016/j.isci.2022.103953] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Human fungal pathogens are the causative agents of devastating diseases across the globe, and the increasing prevalence of drug resistance threatens to undermine the already limited treatment options. One prominent pathogen is the opportunistic fungus Candida albicans, which can cause both superficial and serious systemic infections in immunocompromised individuals. C. albicans antifungal drug resistance and antifungal tolerance are supported by diverse and expansive cellular stress response pathways. Some of the major players are the Ca2+-calmodulin-activated phosphatase calcineurin, the protein kinase C cell wall integrity pathway, and the molecular chaperone heat shock protein 90. Beyond these core signal transducers, several other enzymes and transcription factors have been implicated in both tolerance and resistance. Here, we highlight some of the major stress response pathways, key advances in identifying chemical matter to inhibit these pathways, and implications for C. albicans persistence in the host. Candida albicans can cause superficial and serious systemic infections in humans Stress response pathways regulate C. albicans antifungal resistance and tolerance Stress response regulators include calcineurin, Pkc1, Hsp90, and many others Stress response inhibitors could reduce the likelihood of fungi persisting in humans
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Affiliation(s)
- Kali R. Iyer
- Department of Molecular Genetics, University of Toronto, 661 University Avenue, MaRS Centre, West Tower, Room 1638, Toronto, ON M5G 1M1, Canada
| | - Nicole Robbins
- Department of Molecular Genetics, University of Toronto, 661 University Avenue, MaRS Centre, West Tower, Room 1638, Toronto, ON M5G 1M1, Canada
| | - Leah E. Cowen
- Department of Molecular Genetics, University of Toronto, 661 University Avenue, MaRS Centre, West Tower, Room 1638, Toronto, ON M5G 1M1, Canada
- Corresponding author
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27
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Li C, Tu J, Han G, Liu N, Sheng C. Heat shock protein 90 (Hsp90)/Histone deacetylase (HDAC) dual inhibitors for the treatment of azoles-resistant Candida albicans. Eur J Med Chem 2022; 227:113961. [PMID: 34742014 DOI: 10.1016/j.ejmech.2021.113961] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 10/19/2021] [Accepted: 10/26/2021] [Indexed: 12/22/2022]
Abstract
Clinical treatment of candidiasis has suffered from increasingly severe drug resistance and limited efficacy. Thus, novel strategies to deal with drug resistance are highly desired to develop effective therapeutic agents. Herein, dual inhibition of heat shock protein 90 (Hsp90) and histone deacetylase (HDAC) was validated as a new strategy to potentiate efficacy of fluconazole against resistant Candida albicans infections. The first generation of Hsp90/HDAC dual inhibitors were designed as synergistic enhancers to treat azoles-resistant candidiasis. In particular, compound J5 exhibited fungal-selective inhibitory effects on Hsp90 and HDACs, leading to low toxicity and excellent in vitro (FICI = 0.266) and in vivo synergistic antifungal potency to treat fluconazole resistant candidiasis. Antifungal-mechanistic investigation revealed that compound J5 suppressed important virulence factors and down-regulated expression of resistance-associated genes. Therefore, Hsp90/HDAC dual inhibitors represent a new strategy for the development of novel antifungal therapeutics to combat azole-resistant candidiasis.
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Affiliation(s)
- Chaochen Li
- Department of Medicinal Chemistry, School of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai, 200433, China
| | - Jie Tu
- Department of Medicinal Chemistry, School of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai, 200433, China
| | - Guiyan Han
- Department of Medicinal Chemistry, School of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai, 200433, China
| | - Na Liu
- Department of Medicinal Chemistry, School of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai, 200433, China.
| | - Chunquan Sheng
- Department of Medicinal Chemistry, School of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai, 200433, China.
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28
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Tuo Y, Li G, Liu Z, Yu N, Li Y, Yang L, Liu H, Wang Y. Discovery of novel antifungal resorcylate aminopyrazole Hsp90 inhibitors based on structural optimization by molecular simulations. NEW J CHEM 2022. [DOI: 10.1039/d1nj04927e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Novel antifungal resorcylate aminopyrazole Hsp90 inhibitors were discovered by 3D-QSAR, molecular docking and molecular dynamics simulations.
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Affiliation(s)
- Yan Tuo
- School of Pharmacy and Bioengineering, Chongqing University of Technology, Chongqing 400054, China
| | - Guangping Li
- School of Pharmacy and Bioengineering, Chongqing University of Technology, Chongqing 400054, China
| | - Zhou Liu
- School of Pharmacy and Bioengineering, Chongqing University of Technology, Chongqing 400054, China
| | - Na Yu
- School of Pharmacy and Bioengineering, Chongqing University of Technology, Chongqing 400054, China
| | - Yuepeng Li
- School of Pharmacy and Bioengineering, Chongqing University of Technology, Chongqing 400054, China
| | - Li Yang
- School of Pharmacy and Bioengineering, Chongqing University of Technology, Chongqing 400054, China
| | - Haibin Liu
- National Engineering Research Center for Gelatin-based Traditional Chinese Medicine, Dong-E-E-Jiao Co. Ltd., Shandong Province, 252201, China
| | - Yuanqiang Wang
- School of Pharmacy and Bioengineering, Chongqing University of Technology, Chongqing 400054, China
- Chongqing Key Laboratory of Medicinal Chemistry & Molecular Pharmacology, Chongqing University of Technology, Chongqing, 400054, China
- Chongqing Key Laboratory of Target Based Drug Screening and Activity Evaluation, Chongqing University of Technology, Chongqing, 400054, China
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400716, China
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Uthayakumar D, Sharma J, Wensing L, Shapiro RS. CRISPR-Based Genetic Manipulation of Candida Species: Historical Perspectives and Current Approaches. Front Genome Ed 2021; 2:606281. [PMID: 34713231 PMCID: PMC8525362 DOI: 10.3389/fgeed.2020.606281] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 12/09/2020] [Indexed: 12/26/2022] Open
Abstract
The Candida genus encompasses a diverse group of ascomycete fungi that have captured the attention of the scientific community, due to both their role in pathogenesis and emerging applications in biotechnology; the development of gene editing tools such as CRISPR, to analyze fungal genetics and perform functional genomic studies in these organisms, is essential to fully understand and exploit this genus, to further advance antifungal drug discovery and industrial value. However, genetic manipulation of Candida species has been met with several distinctive barriers to progress, such as unconventional codon usage in some species, as well as the absence of a complete sexual cycle in its diploid members. Despite these challenges, the last few decades have witnessed an expansion of the Candida genetic toolbox, allowing for diverse genome editing applications that range from introducing a single point mutation to generating large-scale mutant libraries for functional genomic studies. Clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 technology is among the most recent of these advancements, bringing unparalleled versatility and precision to genetic manipulation of Candida species. Since its initial applications in Candida albicans, CRISPR-Cas9 platforms are rapidly evolving to permit efficient gene editing in other members of the genus. The technology has proven useful in elucidating the pathogenesis and host-pathogen interactions of medically relevant Candida species, and has led to novel insights on antifungal drug susceptibility and resistance, as well as innovative treatment strategies. CRISPR-Cas9 tools have also been exploited to uncover potential applications of Candida species in industrial contexts. This review is intended to provide a historical overview of genetic approaches used to study the Candida genus and to discuss the state of the art of CRISPR-based genetic manipulation of Candida species, highlighting its contributions to deciphering the biology of this genus, as well as providing perspectives for the future of Candida genetics.
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Affiliation(s)
- Deeva Uthayakumar
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
| | - Jehoshua Sharma
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
| | - Lauren Wensing
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
| | - Rebecca S Shapiro
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada
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Yuan R, Tu J, Sheng C, Chen X, Liu N. Effects of Hsp90 Inhibitor Ganetespib on Inhibition of Azole-Resistant Candida albicans. Front Microbiol 2021; 12:680382. [PMID: 34093502 PMCID: PMC8174564 DOI: 10.3389/fmicb.2021.680382] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Accepted: 04/28/2021] [Indexed: 11/13/2022] Open
Abstract
Candida albicans is the most common fungal pathogen. Recently, drug resistance of C. albicans is increasingly severe. Hsp90 is a promising antifungal target to overcome this problem. To evaluate the effects of Hsp90 inhibitor ganetespib on the inhibition of azole-resistant C. albicans, the microdilution checkerboard method was used to measure the in vitro synergistic efficacy of ganetespib. The XTT/menadione reduction assay, microscopic observation, and Rh6G efflux assay were established to investigate the effects of ganetespib on azole-resistant C. albicans biofilm formation, filamentation, and efflux pump. Real-time RT-PCR analysis was employed to clarify the mechanism of antagonizing drug resistance. The in vivo antifungal efficacy of ganetespib was determined by the infectious model of azole-resistant C. albicans. Ganetespib showed an excellent synergistic antifungal activity in vitro and significantly inhibited the fungal biofilm formation, whereas it had no inhibitory effect on fungal hypha formation. Expression of azole-targeting enzyme gene ERG11 and efflux pump genes CDR1, CDR2, and MDR1 was significantly down-regulated when ganetespib was used in combination with FLC. In a mouse model infected with FLC-resistant C. albicans, the combination of ganetespib and FLC effectively reversed the FLC resistance and significantly decreased the kidney fungal load of mouse.
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Affiliation(s)
- Rui Yuan
- Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, China
| | - Jie Tu
- School of Pharmacy, Second Military Medical University, Shanghai, China
| | - Chunquan Sheng
- School of Pharmacy, Second Military Medical University, Shanghai, China
| | - Xi Chen
- Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, China
| | - Na Liu
- School of Pharmacy, Second Military Medical University, Shanghai, China
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31
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Mattoon ER, Casadevall A, Cordero RJB. Beat the heat: correlates, compounds, and mechanisms involved in fungal thermotolerance. FUNGAL BIOL REV 2021. [DOI: 10.1016/j.fbr.2021.03.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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32
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Li W, Shrivastava M, Lu H, Jiang Y. Calcium-calcineurin signaling pathway in Candida albicans: A potential drug target. Microbiol Res 2021; 249:126786. [PMID: 33989979 DOI: 10.1016/j.micres.2021.126786] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 04/27/2021] [Accepted: 05/03/2021] [Indexed: 12/26/2022]
Abstract
Increased morbidity and mortality of candidiasis are a notable threat to the immunocompromised patients. At present, the types of drugs available to treat C. albicans infection are relatively limited. Moreover, the emergence of antifungal drug resistance of C. albicans makes the treatment of C. albicans infection more difficult. The calcium-calcineurin signaling pathway plays a crucial role in the survival and pathogenicity of C. albicans and may act as a potential target against C. albicans. In this review, we summarized functions of the calcium-calcineurin signaling pathway in several biological processes, compared the differences of this signaling pathway between C. albicans and humans, and described anti-C. albicans activity of inhibitors of this signaling pathway. We believe that targeting the calcium-calcineurin signaling pathway is a promising strategy to cope with C. albicans infection.
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Affiliation(s)
- Wanqian Li
- Department of Pharmacology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China
| | | | - Hui Lu
- Department of Pharmacology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.
| | - Yuanying Jiang
- Department of Pharmacology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.
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33
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Lee Y, Puumala E, Robbins N, Cowen LE. Antifungal Drug Resistance: Molecular Mechanisms in Candida albicans and Beyond. Chem Rev 2021; 121:3390-3411. [PMID: 32441527 PMCID: PMC8519031 DOI: 10.1021/acs.chemrev.0c00199] [Citation(s) in RCA: 278] [Impact Index Per Article: 92.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Fungal infections are a major contributor to infectious disease-related deaths across the globe. Candida species are among the most common causes of invasive mycotic disease, with Candida albicans reigning as the leading cause of invasive candidiasis. Given that fungi are eukaryotes like their human host, the number of unique molecular targets that can be exploited for antifungal development remains limited. Currently, there are only three major classes of drugs approved for the treatment of invasive mycoses, and the efficacy of these agents is compromised by the development of drug resistance in pathogen populations. Notably, the emergence of additional drug-resistant species, such as Candida auris and Candida glabrata, further threatens the limited armamentarium of antifungals available to treat these serious infections. Here, we describe our current arsenal of antifungals and elaborate on the resistance mechanisms Candida species possess that render them recalcitrant to therapeutic intervention. Finally, we highlight some of the most promising therapeutic strategies that may help combat antifungal resistance, including combination therapy, targeting fungal-virulence traits, and modulating host immunity. Overall, a thorough understanding of the mechanistic principles governing antifungal drug resistance is fundamental for the development of novel therapeutics to combat current and emerging fungal threats.
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Affiliation(s)
- Yunjin Lee
- Department of Molecular Genetics, University of Toronto, 661 University Avenue, Toronto, Ontario M5G 1M1, Canada
| | - Emily Puumala
- Department of Molecular Genetics, University of Toronto, 661 University Avenue, Toronto, Ontario M5G 1M1, Canada
| | - Nicole Robbins
- Department of Molecular Genetics, University of Toronto, 661 University Avenue, Toronto, Ontario M5G 1M1, Canada
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, 661 University Avenue, Toronto, Ontario M5G 1M1, Canada
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34
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Horianopoulos LC, Kronstad JW. Chaperone Networks in Fungal Pathogens of Humans. J Fungi (Basel) 2021; 7:209. [PMID: 33809191 PMCID: PMC7998936 DOI: 10.3390/jof7030209] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Revised: 03/05/2021] [Accepted: 03/10/2021] [Indexed: 12/14/2022] Open
Abstract
The heat shock proteins (HSPs) function as chaperones to facilitate proper folding and modification of proteins and are of particular importance when organisms are subjected to unfavourable conditions. The human fungal pathogens are subjected to such conditions within the context of infection as they are exposed to human body temperature as well as the host immune response. Herein, the roles of the major classes of HSPs are briefly reviewed and their known contributions in human fungal pathogens are described with a focus on Candida albicans, Cryptococcus neoformans, and Aspergillus fumigatus. The Hsp90s and Hsp70s in human fungal pathogens broadly contribute to thermotolerance, morphological changes required for virulence, and tolerance to antifungal drugs. There are also examples of J domain co-chaperones and small HSPs influencing the elaboration of virulence factors in human fungal pathogens. However, there are diverse members in these groups of chaperones and there is still much to be uncovered about their contributions to pathogenesis. These HSPs do not act in isolation, but rather they form a network with one another. Interactions between chaperones define their specific roles and enhance their protein folding capabilities. Recent efforts to characterize these HSP networks in human fungal pathogens have revealed that there are unique interactions relevant to these pathogens, particularly under stress conditions. The chaperone networks in the fungal pathogens are also emerging as key coordinators of pathogenesis and antifungal drug tolerance, suggesting that their disruption is a promising strategy for the development of antifungal therapy.
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Affiliation(s)
| | - James W. Kronstad
- Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada;
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35
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Azole-triphenylphosphonium conjugates combat antifungal resistance and alleviate the development of drug-resistance. Bioorg Chem 2021; 110:104771. [PMID: 33714761 DOI: 10.1016/j.bioorg.2021.104771] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 02/05/2021] [Accepted: 02/21/2021] [Indexed: 11/24/2022]
Abstract
Azole antifungals are commonly used to treat fungal infections but have resulted in the occurrence of drug resistance. Therefore, developing azole derivatives (AZDs) that can both combat established drug-resistant fungal strains and evade drug resistance is of great importance. In this study, we synthesized a series of AZDs with a fluconazole (FLC) skeleton conjugated with a mitochondria-targeting triphenylphosphonium cation (TPP+). These AZDs displayed potent activity against both azole-sensitive and azole-resistant Candida strains without eliciting obvious resistance. Moreover, two representative AZDs, 20 and 25, exerted synergistic antifungal activity with Hsp90 inhibitors against C. albicans strains resistant to the combination treatment of FLC and Hsp90 inhibitors. AZD 25, which had minimal cytotoxicity, was effective in preventing C. albicans biofilm formation. Mechanistic investigation revealed that AZD 25 inhibited the biosynthesis of the fungal membrane component ergosterol and interfered with mitochondrial function. Our findings provide an alternative approach to address fungal resistance problems.
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36
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Lu H, Shrivastava M, Whiteway M, Jiang Y. Candida albicans targets that potentially synergize with fluconazole. Crit Rev Microbiol 2021; 47:323-337. [PMID: 33587857 DOI: 10.1080/1040841x.2021.1884641] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Fluconazole has characteristics that make it widely used in the clinical treatment of C. albicans infections. However, fluconazole has only a fungistatic activity in C. albicans, therefore, in the long-term treatment of C. albicans infection with fluconazole, C. albicans has the potential to acquire fluconazole resistance. A promising approach to increase fluconazole's efficacy is identifying potential targets of drugs that can enhance the antifungal effect of fluconazole, or even make the drug fungicidal. In this review, we systematically provide a global overview of potential targets of drugs synergistic with fluconazole in C. albicans, identify new avenues for research on fluconazole potentiation, and highlight the promise of combinatorial strategies with fluconazole in combatting C. albicans infections.
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Affiliation(s)
- Hui Lu
- Department of Pharmacology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China
| | | | - Malcolm Whiteway
- Department of Biology, Concordia University, Montreal, QC, Canada
| | - Yuanying Jiang
- Department of Pharmacology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China
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37
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Updates in Paracoccidioides Biology and Genetic Advances in Fungus Manipulation. J Fungi (Basel) 2021; 7:jof7020116. [PMID: 33557381 PMCID: PMC7915485 DOI: 10.3390/jof7020116] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/30/2021] [Accepted: 02/02/2021] [Indexed: 12/28/2022] Open
Abstract
The dimorphic fungi of the Paracoccidioides genus are the causative agents of paracoccidioidomycosis (PCM). This disease is endemic in Latin America and primarily affects workers in rural areas. PCM is considered a neglected disease, despite being a disabling disease that has a notable impact on the public health system. Paracoccidioides spp. are thermally dimorphic fungi that present infective mycelia at 25 °C and differentiate into pathogenic yeast forms at 37 °C. This transition involves a series of morphological, structural, and metabolic changes which are essential for their survival inside hosts. As a pathogen, the fungus is subjected to several varieties of stress conditions, including the host immune response, which involves the production of reactive nitrogen and oxygen species, thermal stress due to temperature changes during the transition, pH alterations within phagolysosomes, and hypoxia inside granulomas. Over the years, studies focusing on understanding the establishment and development of PCM have been conducted with several limitations due to the low effectiveness of strategies for the genetic manipulation of Paracoccidioides spp. This review describes the most relevant biological features of Paracoccidioides spp., including aspects of the phylogeny, ecology, stress response, infection, and evasion mechanisms of the fungus. We also discuss the genetic aspects and difficulties of fungal manipulation, and, finally, describe the advances in molecular biology that may be employed in molecular research on this fungus in the future.
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38
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Marcyk PT, LeBlanc EV, Kuntz DA, Xue A, Ortiz F, Trilles R, Bengtson S, Kenney TM, Huang DS, Robbins N, Williams NS, Krysan DJ, Privé GG, Whitesell L, Cowen LE, Brown LE. Fungal-Selective Resorcylate Aminopyrazole Hsp90 Inhibitors: Optimization of Whole-Cell Anticryptococcal Activity and Insights into the Structural Origins of Cryptococcal Selectivity. J Med Chem 2021; 64:1139-1169. [PMID: 33444025 PMCID: PMC8493596 DOI: 10.1021/acs.jmedchem.0c01777] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The essential eukaryotic chaperone Hsp90 regulates the form and function of diverse client proteins, many of which govern thermotolerance, virulence, and drug resistance in fungal species. However, use of Hsp90 inhibitors as antifungal therapeutics has been precluded by human host toxicities and suppression of immune responses. We recently described resorcylate aminopyrazoles (RAPs) as the first class of Hsp90 inhibitors capable of discriminating between fungal (Cryptococcus neoformans, Candida albicans) and human isoforms of Hsp90 in biochemical assays. Here, we report an iterative structure-property optimization toward RAPs capable of inhibiting C. neoformans growth in culture. In addition, we report the first X-ray crystal structures of C. neoformans Hsp90 nucleotide binding domain (NBD), as the apoprotein and in complexes with the non-species-selective Hsp90 inhibitor NVP-AUY922 and three RAPs revealing unique ligand-induced conformational rearrangements, which reaffirm the hypothesis that intrinsic differences in protein flexibility can confer selective inhibition of fungal versus human Hsp90 isoforms.
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Affiliation(s)
- Paul T. Marcyk
- Department of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, Boston, Massachusetts 02215, United States
| | - Emmanuelle V. LeBlanc
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, M5G 1M1, Canada
| | - Douglas A. Kuntz
- Princess Margaret Cancer Centre, Toronto, Ontario, M5G 1L7, Canada
| | - Alice Xue
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, M5G 1M1, Canada
| | - Francisco Ortiz
- Department of Biochemistry, UT Southwestern Medical Center, Dallas, Texas 75390-9038, United States
| | - Richard Trilles
- Department of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, Boston, Massachusetts 02215, United States
| | - Stephen Bengtson
- Department of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, Boston, Massachusetts 02215, United States
| | - Tristan M.G. Kenney
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, M5G 1L7, Canada
| | - David S. Huang
- Department of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, Boston, Massachusetts 02215, United States
| | - Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, M5G 1M1, Canada
| | - Noelle S. Williams
- Department of Biochemistry, UT Southwestern Medical Center, Dallas, Texas 75390-9038, United States
| | - Damian J. Krysan
- Departments of Pediatrics and Microbiology/Immunology, Carver College of Medicine, University of Iowa, Iowa City, Iowa, 52242, United States
| | - Gilbert G. Privé
- Princess Margaret Cancer Centre, Toronto, Ontario, M5G 1L7, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, M5G 1L7, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
| | - Luke Whitesell
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, M5G 1M1, Canada
| | - Leah E. Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, M5G 1M1, Canada
| | - Lauren E. Brown
- Department of Chemistry and Center for Molecular Discovery (BU-CMD), Boston University, Boston, Massachusetts 02215, United States
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39
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LeBlanc EV, Shekhar-Guturja T, Whitesell L, Cowen LE. Fluorescence Polarization-Based Measurement of Protein-Ligand Interaction in Fungal Cell Lysates. Curr Protoc 2021; 1:e17. [PMID: 33484500 DOI: 10.1002/cpz1.17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Fungi infect over a billion people worldwide and contribute substantially to human morbidity and mortality despite all available therapies. New antifungal drugs are urgently needed. Decades of study have revealed numerous protein targets of potential therapeutic interest for which potent, fungal-selective ligands remain to be discovered and developed. To measure the binding of diverse small molecule ligands to their larger protein targets, fluorescence polarization (FP) can provide a robust, inexpensive approach. The protocols in this article provide detailed guidance for developing FP-based assays capable of measuring binding affinity in whole cell lysates without the need for purification of the target protein. Applications include screening of libraries to identify novel ligands and the definition of structure-activity relationships to aid development of compounds with improved target affinity and fungal selectivity. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Use of saturation binding curves to optimize tracer and lysate protein concentrations Basic Protocol 2: Establishment of competition binding experiments Support Protocol 1: Preparation of fungal cell lysates Support Protocol 2: Preparation of human HepG2 cell lysate.
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Affiliation(s)
- Emmanuelle V LeBlanc
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | | | - Luke Whitesell
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
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40
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Treatment strategies for cryptococcal infection: challenges, advances and future outlook. Nat Rev Microbiol 2021; 19:454-466. [PMID: 33558691 PMCID: PMC7868659 DOI: 10.1038/s41579-021-00511-0] [Citation(s) in RCA: 120] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/07/2021] [Indexed: 01/31/2023]
Abstract
Cryptococcus spp., in particular Cryptococcus neoformans and Cryptococcus gattii, have an enormous impact on human health worldwide. The global burden of cryptococcal meningitis is almost a quarter of a million cases and 181,000 deaths annually, with mortality rates of 100% if infections remain untreated. Despite these alarming statistics, treatment options for cryptococcosis remain limited, with only three major classes of drugs approved for clinical use. Exacerbating the public health burden is the fact that the only new class of antifungal drugs developed in decades, the echinocandins, displays negligible antifungal activity against Cryptococcus spp., and the efficacy of the remaining therapeutics is hampered by host toxicity and pathogen resistance. Here, we describe the current arsenal of antifungal agents and the treatment strategies employed to manage cryptococcal disease. We further elaborate on the recent advances in our understanding of the intrinsic and adaptive resistance mechanisms that are utilized by Cryptococcus spp. to evade therapeutic treatments. Finally, we review potential therapeutic strategies, including combination therapy, the targeting of virulence traits, impairing stress response pathways and modulating host immunity, to effectively treat infections caused by Cryptococcus spp. Overall, understanding of the mechanisms that regulate anti-cryptococcal drug resistance, coupled with advances in genomics technologies and high-throughput screening methodologies, will catalyse innovation and accelerate antifungal drug discovery.
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41
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Ali D, Panday AK, Choudhury LH. Hydrogen Peroxide-Mediated Rapid Room Temperature Metal-Free C(sp 2)-H Thiocyanation of Amino Pyrazoles, Amino Uracils, and Enamines. J Org Chem 2020; 85:13610-13620. [PMID: 33054213 DOI: 10.1021/acs.joc.0c01738] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A rapid metal- and additive-free room temperature method for C(sp2)-H thiocyanation of aminopyrazoles, aminoisoxazole, aminoisothiazole, amino uracils, and aliphatic enamines has been developed in an aqueous medium using hydrogen peroxide as a benign oxidant and ammonium thiocyanate as a thiocyanating agent. On the other hand, the reaction of hydrogen peroxide and ammonium thiocyanate followed by one-pot addition of NaOH provides the corresponding disulfides in the case of amino azoles, and pyrimidine-fused 2-amino thiazoles were observed in the case of aminouracils. The salient features of this method are the use of an eco-friendly oxidant, reaction tunability to access different products, wide substrate scope, and good to very good yields.
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Affiliation(s)
- Danish Ali
- Department of Chemistry, Indian Institute of Technology Patna, Bihta, Patna 801106, India
| | - Anoop Kumar Panday
- Department of Chemistry, Indian Institute of Technology Patna, Bihta, Patna 801106, India
| | - Lokman H Choudhury
- Department of Chemistry, Indian Institute of Technology Patna, Bihta, Patna 801106, India
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42
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LeBlanc EV, Polvi EJ, Veri AO, Privé GG, Cowen LE. Structure-guided approaches to targeting stress responses in human fungal pathogens. J Biol Chem 2020; 295:14458-14472. [PMID: 32796038 DOI: 10.1074/jbc.rev120.013731] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 08/11/2020] [Indexed: 11/06/2022] Open
Abstract
Fungi inhabit extraordinarily diverse ecological niches, including the human body. Invasive fungal infections have a devastating impact on human health worldwide, killing ∼1.5 million individuals annually. The majority of these deaths are attributable to species of Candida, Cryptococcus, and Aspergillus Treating fungal infections is challenging, in part due to the emergence of resistance to our limited arsenal of antifungal agents, necessitating the development of novel therapeutic options. Whereas conventional antifungal strategies target proteins or cellular components essential for fungal growth, an attractive alternative strategy involves targeting proteins that regulate fungal virulence or antifungal drug resistance, such as regulators of fungal stress responses. Stress response networks enable fungi to adapt, grow, and cause disease in humans and include regulators that are highly conserved across eukaryotes as well as those that are fungal-specific. This review highlights recent developments in elucidating crystal structures of fungal stress response regulators and emphasizes how this knowledge can guide the design of fungal-selective inhibitors. We focus on the progress that has been made with highly conserved regulators, including the molecular chaperone Hsp90, the protein phosphatase calcineurin, and the small GTPase Ras1, as well as with divergent stress response regulators, including the cell wall kinase Yck2 and trehalose synthases. Exploring structures of these important fungal stress regulators will accelerate the design of selective antifungals that can be deployed to combat life-threatening fungal diseases.
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Affiliation(s)
- Emmanuelle V LeBlanc
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Elizabeth J Polvi
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Amanda O Veri
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Gilbert G Privé
- Departments of Medical Biophysics and Biochemistry, University of Toronto, Toronto, Ontario, Canada.,Princess Margaret Cancer Centre, Toronto, Ontario, Canada
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
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43
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Skrzypczak N, Pyta K, Ruszkowski P, Gdaniec M, Bartl F, Przybylski P. Synthesis, structure and anticancer activity of new geldanamycin amine analogs containing C(17)- or C(20)- flexible and rigid arms as well as closed or open ansa-bridges. Eur J Med Chem 2020; 202:112624. [PMID: 32663707 DOI: 10.1016/j.ejmech.2020.112624] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 06/10/2020] [Accepted: 06/25/2020] [Indexed: 12/15/2022]
Abstract
The nucleophilic attack of amines at C(17) or C(17)/C(20) positions of geldanamycin's (GDM) benzoquinone, via initial 1,4-Michael conjugate addition mechanism, yield new analogs with closed or open ansa-bridges (1-31), respectively. X-ray structures of analogs 22 and 24 reveals an unexpected arrangement of the ansa-bridge in solid (conformer B), that is located between those of conformers A, prevailing in solution (trans-lactam), and C, crucial at binding to Hsp90 (cis-lactam). The structure of a new-type conformer B allows to better understand the molecular recognition mechanism between the GDM analogs and the target Hsp90. Combined analysis of: anticancer test results (SKBR-3, SKOV-3, PC-3, U-87, A-549) and those performed in normal cells (HDF), KD values and docking modes at Hsp90 as well as clogP parameters, reveals that the rigid C(17)-arm (piperidyl, cyclohexyl) with a H-bond acceptor as carbonyl group together with a lipophilicity clogP∼3 favor high potency of analogs, even up to IC50 ∼0.08 μM, at improved selectivity (SIHDF > 30), when compared to GDM. The most active 25 show higher anticancer potency than 17-AAG (in SKOV-3 and A-549) as well as reblastatin (in SKBR-3 and SKOV-3). Opening of the ansa-bridge within GDM analogs, at the best case, decreases activity (IC50∼2 μM) and toxicity in HDF cells (SIHDF∼2-3), relative to GDM.
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Affiliation(s)
- Natalia Skrzypczak
- Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznanskiego 8, 61-614, Poznan, Poland
| | - Krystian Pyta
- Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznanskiego 8, 61-614, Poznan, Poland
| | - Piotr Ruszkowski
- Department of Pharmacology, University of Medical Sciences, Rokietnicka 5a, 60-806, Poznan, Poland
| | - Maria Gdaniec
- Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznanskiego 8, 61-614, Poznan, Poland
| | - Franz Bartl
- Lebenswissenschaftliche Fakultät, Institut für Biologie, Biophysikalische Chemie Humboldt-Universität zu Berlin, Invalidenstrasse 42, 10099, Berlin, Germany
| | - Piotr Przybylski
- Faculty of Chemistry, Adam Mickiewicz University, Uniwersytetu Poznanskiego 8, 61-614, Poznan, Poland.
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The Proteasome Governs Fungal Morphogenesis via Functional Connections with Hsp90 and cAMP-Protein Kinase A Signaling. mBio 2020; 11:mBio.00290-20. [PMID: 32317319 PMCID: PMC7175089 DOI: 10.1128/mbio.00290-20] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Protein homeostasis is critical for proliferation and viability of all organisms. For Candida albicans, protein homeostasis also modulates the transition between yeast and filamentous forms, which is critical for virulence. A key regulator of morphogenesis is the molecular chaperone Hsp90, which mediates proteostasis under physiological and stress conditions. Hsp90 regulates morphogenesis by repressing cyclic AMP-protein kinase A (cAMP-PKA) signaling, such that inhibition of Hsp90 causes filamentation in the absence of an inducing cue. We explored the effect of perturbation of another facet of protein homeostasis and discovered that morphogenesis is also regulated by the proteasome, a large 33-subunit protein complex consisting of a 20S catalytic core and two 19S regulatory particles, which controls degradation of intracellular proteins. We identified a conserved role of the proteasome in morphogenesis as pharmacological inhibition of the proteasome induced filamentation of C. albicans and the related species Candida dubliniensis, Candida tropicalis, Candida krusei, and Candida parapsilosis For C. albicans, genetic depletion of any of 29 subunits of the 19S or 20S particle induced filamentation. Filaments induced by inhibition of either the proteasome or Hsp90 have shared structural characteristics, such as aberrant nuclear content, and shared genetic dependencies, such as intact cAMP-PKA signaling. Consistent with a functional connection between these facets of protein homeostasis that modulate morphogenesis, we observed that proteasome inhibition results in an accumulation of ubiquitinated proteins that overwhelm Hsp90 function, relieving Hsp90-mediated repression of morphogenesis. Together, our findings provide a mechanism whereby interconnected facets of proteostasis regulate C. albicans morphogenesis.IMPORTANCE Fungi cause life-threatening infections and pose a serious threat to human health as there are very few effective antifungal drugs. Candida albicans is a major human fungal pathogen and cause of morbidity and mortality in immunocompromised individuals. A key trait that enables C. albicans virulence is its ability to transition between yeast and filamentous forms. Understanding the mechanisms regulating this virulence trait can facilitate the development of much-needed, novel therapeutic strategies. A key regulator of morphogenesis is the molecular chaperone Hsp90, which is crucial for proteostasis. Here, we expanded our understanding of how proteostasis regulates fungal morphogenesis and identified the proteasome as a repressor of filamentation in C. albicans and related species. Our work suggests that proteasome inhibition overwhelms Hsp90 function, thereby inducing morphogenesis. This work provides a foundation for understanding the role of the proteasome in fungal virulence and offers potential for targeting the proteasome to disarm fungal pathogens.
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