1
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Mo C, Wei N, Li T, Ahmed Bhat M, Mohammadi M, Kuang C. CDK9 inhibitors for the treatment of solid tumors. Biochem Pharmacol 2024:116470. [PMID: 39127153 DOI: 10.1016/j.bcp.2024.116470] [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: 05/14/2024] [Revised: 08/04/2024] [Accepted: 08/05/2024] [Indexed: 08/12/2024]
Abstract
Cyclin-dependent kinase 9 (CDK9) regulates mRNA transcription by promoting RNA Pol II elongation. CDK9 is now emerging as a potential therapeutic target for cancer, since its overexpression has been found to correlate with cancer development and worse clinical outcomes. While much work on CDK9 inhibition has focused on hematologic malignancies, the role of this cancer driver in solid tumors is starting to come into focus. Many solid cancers also overexpress CDK9 and depend on its activity to promote downstream oncogenic signaling pathways. In this review, we summarize the latest knowledge of CDK9 biology in solid tumors and the studies of small molecule CDK9 inhibitors. We discuss the results of the latest clinical trials of CDK9 inhibitors in solid tumors, with a focus on key issues to consider for improving the therapeutic impact of this drug class.
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Affiliation(s)
- Christiana Mo
- Department of Oncology, Montefiore Einstein, Bronx, NY, USA; Montefiore Einstein Comprehensive Cancer Center, Bronx, NY, USA
| | - Ning Wei
- Department of Oncology, Montefiore Einstein, Bronx, NY, USA; Montefiore Einstein Comprehensive Cancer Center, Bronx, NY, USA; Department of Molecular Pharmacology, Montefiore Einstein, Bronx, NY, USA
| | - Terence Li
- Department of Oncology, Montefiore Einstein, Bronx, NY, USA; Montefiore Einstein Comprehensive Cancer Center, Bronx, NY, USA; Department of Molecular Pharmacology, Montefiore Einstein, Bronx, NY, USA
| | - Muzaffer Ahmed Bhat
- Department of Oncology, Montefiore Einstein, Bronx, NY, USA; Montefiore Einstein Comprehensive Cancer Center, Bronx, NY, USA; Department of Molecular Pharmacology, Montefiore Einstein, Bronx, NY, USA
| | - Mahshid Mohammadi
- Department of Oncology, Montefiore Einstein, Bronx, NY, USA; Montefiore Einstein Comprehensive Cancer Center, Bronx, NY, USA; Department of Molecular Pharmacology, Montefiore Einstein, Bronx, NY, USA
| | - Chaoyuan Kuang
- Department of Oncology, Montefiore Einstein, Bronx, NY, USA; Montefiore Einstein Comprehensive Cancer Center, Bronx, NY, USA; Department of Molecular Pharmacology, Montefiore Einstein, Bronx, NY, USA.
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2
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Fu K, Hua J, Zhang Y, Du M, Han J, Li N, Wang Q, Yang L, Li R, Zhou B. Integrated Studies on Male Reproductive Toxicity of Bis(2-ethylhexyl)-tetrabromophthalate: in Silico, in Vitro, ex Vivo, and in Vivo. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:194-206. [PMID: 38113192 DOI: 10.1021/acs.est.3c07129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
Bis(2-ethylhexyl)tetrabromophthalate (TBPH) has been widely detected in the environment and organisms; thus, its toxic effects on male reproduction were systematically studied. First, we found that TBPH can stably bind to the androgen receptor (AR) based on in silico molecular docking results and observed an antagonistic activity, but not agonistic activity, on the AR signaling pathway using a constructed AR-GRIP1 yeast assay. Subsequently, we validated the adverse effects on male germ cells by observing inhibited androgen production and proliferation in Leydig cells upon in vitro exposure and affected general motility and motive tracks of zebrafish sperm upon ex vivo exposure. Finally, the in vivo reproductive toxicity was demonstrated in male zebrafish by reduced mating behavior in F0 generation when paired with unexposed females and abnormal development of their offspring. In addition, reduced sperm motility and impaired germ cells in male zebrafish were also observed, which may be related to the disturbed homeostasis of sex hormones. Notably, the specifically suppressed AR in the brain provides further evidence for the antagonistic effects as above-mentioned. These results confirmed that TBPH affected male reproduction through a classical nuclear receptor-mediated pathway, which would be helpful for assessing the ecological and health risks of TBPH.
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Affiliation(s)
- Kaiyu Fu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jianghuan Hua
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
- School of Basic Medical Sciences, Hubei University of Chinese Medicine, Wuhan 430065, China
| | - Yindan Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Mingpu Du
- Ecology and Environment Monitoring and Scientific Research Center, Ecology and Environment Administration of Yangtze River Basin, Ministry of Ecology and Environment, Wuhan 430010, China
| | - Jian Han
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Na Li
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Qiangwei Wang
- Institute of Pesticide and Environmental Toxicology, Zhejiang University, Hangzhou 310058, China
| | - Lihua Yang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Ruiwen Li
- Ecology and Environment Monitoring and Scientific Research Center, Ecology and Environment Administration of Yangtze River Basin, Ministry of Ecology and Environment, Wuhan 430010, China
| | - Bingsheng Zhou
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
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3
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Henry M, Riley CM, Hunter I, Elwood JML, Lopez-Fernandez JD, Minty L, Coe DM, McEwan IJ, Jamieson C. Synthesis and Evaluation of Small Molecule Inhibitors of the Androgen Receptor N-Terminal Domain. ACS Med Chem Lett 2023; 14:1800-1806. [PMID: 38116409 PMCID: PMC10726465 DOI: 10.1021/acsmedchemlett.3c00426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 11/10/2023] [Accepted: 11/13/2023] [Indexed: 12/21/2023] Open
Abstract
The androgen receptor (AR) is central to prostate cancer pathogenesis and has been extensively validated as a drug target. However, small-molecule anti-androgen therapies remain limited due to resistance and will eventually fail to suppress tumor growth, resulting in progression to castration-resistant prostate cancer (CRPC). The intrinsically disordered N-terminal domain (NTD) is crucial for AR transactivation and has been investigated as a suitable target in the presence of ligand binding domain mutations. A screening campaign identified biaryl isoxazole compound 7 as a weak inhibitor of the AR NTD. A library of biaryl analogues were synthesized, and their biological activities were assessed in a VCaP cell-based luciferase reporter gene assay. A structure-activity relationship (SAR) study revealed that indazole analogue 16 exhibited increased potency and favorable physicochemical properties with a benchmarked pharmacokinetic profile, providing a suitable starting point for further optimization of 16 as a CRPC therapeutic in the presence of AR mutations.
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Affiliation(s)
- Martyn
C. Henry
- Department
of Pure and Applied Chemistry, University
of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, U.K.
| | - Christopher M. Riley
- Department
of Pure and Applied Chemistry, University
of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, U.K.
| | - Irene Hunter
- Institute
of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, U.K.
| | - Jessica M. L. Elwood
- Department
of Pure and Applied Chemistry, University
of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, U.K.
| | - J. Daniel Lopez-Fernandez
- Department
of Pure and Applied Chemistry, University
of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, U.K.
| | - Laura Minty
- Department
of Pure and Applied Chemistry, University
of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, U.K.
| | - Diane M. Coe
- Medicine
Design, GlaxoSmithKline R&D Ltd, Gunnels Wood Road, Stevenage, Hertfordshire SG1 2NY, U.K.
| | - Iain J. McEwan
- Institute
of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, U.K.
| | - Craig Jamieson
- Department
of Pure and Applied Chemistry, University
of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, U.K.
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4
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Riley CM, Elwood JML, Henry MC, Hunter I, Daniel Lopez-Fernandez J, McEwan IJ, Jamieson C. Current and emerging approaches to noncompetitive AR inhibition. Med Res Rev 2023; 43:1701-1747. [PMID: 37062876 DOI: 10.1002/med.21961] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 03/14/2023] [Accepted: 03/28/2023] [Indexed: 04/18/2023]
Abstract
The androgen receptor (AR) has been shown to be a key determinant in the pathogenesis of castration-resistant prostate cancer (CRPC). The current standard of care therapies targets the ligand-binding domain of the receptor and can afford improvements to life expectancy often only in the order of months before resistance occurs. Emerging preclinical and clinical compounds that inhibit receptor activity via differentiated mechanisms of action which are orthogonal to current antiandrogens show promise for overcoming treatment resistance. In this review, we present an authoritative summary of molecules that noncompetitively target the AR. Emerging small molecule strategies for targeting alternative domains of the AR represent a promising area of research that shows significant potential for future therapies. The overall quality of lead candidates in the area of noncompetitive AR inhibition is discussed, and it identifies the key chemotypes and associated properties which are likely to be, or are currently, positioned to be first in human applications.
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Affiliation(s)
- Christopher M Riley
- Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, UK
| | - Jessica M L Elwood
- Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, UK
| | - Martyn C Henry
- Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, UK
| | - Irene Hunter
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | | | - Iain J McEwan
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - Craig Jamieson
- Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, UK
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5
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Ducker C, Ratnam M, Shaw PE, Layfield R. Comparative analysis of protein expression systems and PTM landscape in the study of transcription factor ELK-1. Protein Expr Purif 2023; 203:106216. [PMID: 36528218 DOI: 10.1016/j.pep.2022.106216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 12/06/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022]
Abstract
Post-translational modifications (PTMs) are important for protein folding and activity, and the ability to recreate physiologically relevant PTM profiles on recombinantly-expressed proteins is vital for meaningful functional analysis. The ETS transcription factor ELK-1 serves as a paradigm for cellular responses to mitogens and can synergise with androgen receptor to promote prostate cancer progression, although in vitro protein function analyses to date have largely overlooked its complex PTM landscapes. We expressed and purified human ELK-1 using mammalian (HEK293T), insect (Sf9) and bacterial (E. coli) systems in parallel and compared PTMs imparted upon purified proteins, along with their performance in DNA and protein interaction assays. Phosphorylation of ELK-1 within its transactivation domain, known to promote DNA binding, was most apparent in protein isolated from human cells and accordingly conferred the strongest DNA binding in vitro, while protein expressed in insect cells bound most efficiently to the androgen receptor. We observed lysine acetylation, a hitherto unreported PTM of ELK-1, which appeared highest in insect cell-derived ELK-1 but was also present in HEK293T-derived ELK-1. Acetylation of ELK-1 was enhanced in HEK293T cells following starvation and mitogen stimulation, and modified lysines showed overlap with previously identified regulatory SUMOylation and ubiquitination sites. Our data demonstrate that the choice of recombinant expression system can be tailored to suit biochemical application rather than to maximise soluble protein production and suggest the potential for crosstalk and antagonism between different PTMs of ELK-1.
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Affiliation(s)
- Charles Ducker
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, United Kingdom.
| | - Manohar Ratnam
- Department of Oncology, Wayne State University School of Medicine and Barbara Ann Karmanos Cancer Institute, Detroit, MI, USA
| | - Peter E Shaw
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, United Kingdom
| | - Robert Layfield
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, United Kingdom
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6
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Ji Y, Zhang R, Han X, Zhou J. Targeting the N-terminal domain of the androgen receptor: The effective approach in therapy of CRPC. Eur J Med Chem 2023; 247:115077. [PMID: 36587421 DOI: 10.1016/j.ejmech.2022.115077] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 12/28/2022] [Accepted: 12/29/2022] [Indexed: 12/31/2022]
Abstract
The androgen receptor (AR) is dominant in prostate cancer (PCa) pathology. Current therapeutic agents for advanced PCa include androgen synthesis inhibitors and AR antagonists that bind to the hormone binding pocket (HBP) at the ligand binding domain (LBD). However, AR amplification, AR splice variants (AR-Vs) expression, and intra-tumoral de novo synthesis of androgens result in the reactivation of AR signalling. The AR N-terminal domain (NTD) plays an essential role in AR transcriptional activity. The AR inhibitor targeting NTD could potentially block the activation of both full-length AR and AR-Vs, thus overcoming major resistance mechanisms to current treatments. This review discusses the progress of research in various NTD inhibitors and provides new insight into the development of AR-NTD inhibitors.
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Affiliation(s)
- Yang Ji
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Department of Chemistry, Zhejiang Normal University, 688 Yingbin Road, Jinhua, 321004, PR China; Drug Development and Innovation Center, College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yingbin Road, Jinhua, 321004, PR China
| | - Rongyu Zhang
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Department of Chemistry, Zhejiang Normal University, 688 Yingbin Road, Jinhua, 321004, PR China; Drug Development and Innovation Center, College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yingbin Road, Jinhua, 321004, PR China
| | - Xiaoli Han
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Department of Chemistry, Zhejiang Normal University, 688 Yingbin Road, Jinhua, 321004, PR China; Drug Development and Innovation Center, College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yingbin Road, Jinhua, 321004, PR China
| | - Jinming Zhou
- Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Department of Chemistry, Zhejiang Normal University, 688 Yingbin Road, Jinhua, 321004, PR China; Drug Development and Innovation Center, College of Chemistry and Life Sciences, Zhejiang Normal University, 688 Yingbin Road, Jinhua, 321004, PR China.
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7
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Raith F, O’Donovan DH, Lemos C, Politz O, Haendler B. Addressing the Reciprocal Crosstalk between the AR and the PI3K/AKT/mTOR Signaling Pathways for Prostate Cancer Treatment. Int J Mol Sci 2023; 24:ijms24032289. [PMID: 36768610 PMCID: PMC9917236 DOI: 10.3390/ijms24032289] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 01/17/2023] [Accepted: 01/20/2023] [Indexed: 01/27/2023] Open
Abstract
The reduction in androgen synthesis and the blockade of the androgen receptor (AR) function by chemical castration and AR signaling inhibitors represent the main treatment lines for the initial stages of prostate cancer. Unfortunately, resistance mechanisms ultimately develop due to alterations in the AR pathway, such as gene amplification or mutations, and also the emergence of alternative pathways that render the tumor less or, more rarely, completely independent of androgen activation. An essential oncogenic axis activated in prostate cancer is the phosphatidylinositol-3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway, as evidenced by the frequent alterations of the negative regulator phosphatase and tensin homolog (PTEN) and by the activating mutations in PI3K subunits. Additionally, crosstalk and reciprocal feedback loops between androgen signaling and the PI3K/AKT/mTOR signaling cascade that activate pro-survival signals and play an essential role in disease recurrence and progression have been evidenced. Inhibitors addressing different players of the PI3K/AKT/mTOR pathway have been evaluated in the clinic. Only a limited benefit has been reported in prostate cancer up to now due to the associated side effects, so novel combination approaches and biomarkers predictive of patient response are urgently needed. Here, we reviewed recent data on the crosstalk between AR signaling and the PI3K/AKT/mTOR pathway, the selective inhibitors identified, and the most advanced clinical studies, with a focus on combination treatments. A deeper understanding of the complex molecular mechanisms involved in disease progression and treatment resistance is essential to further guide therapeutic approaches with improved outcomes.
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Affiliation(s)
- Fabio Raith
- Research & Development, Pharmaceuticals, Bayer AG, Müllerstr. 178, 13353 Berlin, Germany
| | - Daniel H. O’Donovan
- Research & Development, Pharmaceuticals, Bayer AG, Müllerstr. 178, 13353 Berlin, Germany
| | - Clara Lemos
- Bayer Research and Innovation Center, Bayer US LLC, 238 Main Street, Cambridge, MA 02142, USA
| | - Oliver Politz
- Research & Development, Pharmaceuticals, Bayer AG, Müllerstr. 178, 13353 Berlin, Germany
| | - Bernard Haendler
- Research & Development, Pharmaceuticals, Bayer AG, Müllerstr. 178, 13353 Berlin, Germany
- Correspondence: ; Tel.: +49-30-2215-41198
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8
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Kastano K, Mier P, Dosztányi Z, Promponas VJ, Andrade-Navarro MA. Functional Tuning of Intrinsically Disordered Regions in Human Proteins by Composition Bias. Biomolecules 2022; 12:biom12101486. [PMID: 36291695 PMCID: PMC9599065 DOI: 10.3390/biom12101486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 09/30/2022] [Accepted: 10/11/2022] [Indexed: 11/16/2022] Open
Abstract
Intrinsically disordered regions (IDRs) in protein sequences are flexible, have low structural constraints and as a result have faster rates of evolution. This lack of evolutionary conservation greatly limits the use of sequence homology for the classification and functional assessment of IDRs, as opposed to globular domains. The study of IDRs requires other properties for their classification and functional prediction. While composition bias is not a necessary property of IDRs, compositionally biased regions (CBRs) have been noted as frequent part of IDRs. We hypothesized that to characterize IDRs, it could be helpful to study their overlap with particular types of CBRs. Here, we evaluate this overlap in the human proteome. A total of 2/3 of residues in IDRs overlap CBRs. Considering CBRs enriched in one type of amino acid, we can distinguish CBRs that tend to be fully included within long IDRs (R, H, N, D, P, G), from those that partially overlap shorter IDRs (S, E, K, T), and others that tend to overlap IDR terminals (Q, A). CBRs overlap more often IDRs in nuclear proteins and in proteins involved in liquid-liquid phase separation (LLPS). Study of protein interaction networks reveals the enrichment of CBRs in IDRs by tandem repetition of short linear motifs (rich in S or P), and the existence of E-rich polar regions that could support specific protein interactions with non-specific interactions. Our results open ways to pin down the function of IDRs from their partial compositional biases.
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Affiliation(s)
- Kristina Kastano
- Institute of Organismic and Molecular Evolution, Faculty of Biology, Johannes Gutenberg University, Biozentrum I, Hans-Dieter-Hüsch-Weg 15, 55128 Mainz, Germany
| | - Pablo Mier
- Institute of Organismic and Molecular Evolution, Faculty of Biology, Johannes Gutenberg University, Biozentrum I, Hans-Dieter-Hüsch-Weg 15, 55128 Mainz, Germany
| | - Zsuzsanna Dosztányi
- Department of Biochemistry, ELTE Eötvös Loránd University, Pázmány Péter stny 1/c, H-1117 Budapest, Hungary
| | - Vasilis J. Promponas
- Bioinformatics Research Laboratory, Department of Biological Sciences, University of Cyprus, 1678 Nicosia, Cyprus
| | - Miguel A. Andrade-Navarro
- Institute of Organismic and Molecular Evolution, Faculty of Biology, Johannes Gutenberg University, Biozentrum I, Hans-Dieter-Hüsch-Weg 15, 55128 Mainz, Germany
- Correspondence:
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9
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Quick J, Santos ND, Cheng MHY, Chander N, Brimacombe CA, Kulkarni J, van der Meel R, Tam YYC, Witzigmann D, Cullis PR. Lipid nanoparticles to silence androgen receptor variants for prostate cancer therapy. J Control Release 2022; 349:174-183. [PMID: 35780952 DOI: 10.1016/j.jconrel.2022.06.051] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 06/22/2022] [Accepted: 06/26/2022] [Indexed: 11/18/2022]
Abstract
Advanced-stage prostate cancer remains an incurable disease with poor patient prognosis. There is an unmet clinical need to target androgen receptor (AR) splice variants, which are key drivers of the disease. Some AR splice variants are insensitive to conventional hormonal or androgen deprivation therapy due to loss of the androgen ligand binding domain at the C-terminus and are constitutively active. Here we explore the use of RNA interference (RNAi) to target a universally conserved region of all AR splice variants for cleavage and degradation, thereby eliminating protein level resistance mechanisms. To this end, we tested five siRNA sequences designed against exon 1 of the AR mRNA and identified several that induced potent knockdown of full-length and truncated variant ARs in the 22Rv1 human prostate cancer cell line. We then demonstrated that 2'O methyl modification of the top candidate siRNA (siARvm) enhanced AR and AR-V7 mRNA silencing potency in both 22Rv1 and LNCaP cells, which represent two different prostate cancer models. For downstream in vivo delivery, we formulated siARvm-LNPs and functionally validated these in vitro by demonstrating knockdown of AR and AR-V7 mRNA in prostate cancer cells and loss of AR-mediated transcriptional activation of the PSA gene in both cell lines following treatment. We also observed that siARvm-LNP induced cell viability inhibition was more potent compared to LNP containing siRNA targeting full-length AR mRNA (siARfl-LNP) in 22Rv1 cells as their proliferation is more dependent on AR splice variants than LNCaP and PC3 cells. The in vivo biodistribution of siARvm-LNPs was determined in 22Rv1 tumor-bearing mice by incorporating 14C-radiolabelled DSPC in LNP formulation, and we observed a 4.4% ID/g tumor accumulation following intravenous administration. Finally, treatment of 22Rv1 tumor bearing mice with siARvm-LNP resulted in significant tumor growth inhibition and survival benefit compared to siARfl-LNP or the siLUC-LNP control. To best of our knowledge, this is the first report demonstrating therapeutic effects of LNP-siRNA targeting AR splice variants in prostate cancer.
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Affiliation(s)
- Joslyn Quick
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Nancy Dos Santos
- BC Cancer Research Institute, 675 West 10th Avenue, Vancouver, British Columbia V5Z 1L3, Canada
| | - Miffy H Y Cheng
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Nisha Chander
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Cedric A Brimacombe
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Jayesh Kulkarni
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Roy van der Meel
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Yuen Yi C Tam
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Dominik Witzigmann
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Pieter R Cullis
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada.
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10
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Sheikhhassani V, Scalvini B, Ng J, Heling LWHJ, Ayache Y, Evers TMJ, Estébanez‐Perpiñá E, McEwan IJ, Mashaghi A. Topological dynamics of an intrinsically disordered N‐terminal domain of the human androgen receptor. Protein Sci 2022; 31:e4334. [PMID: 35634773 PMCID: PMC9134807 DOI: 10.1002/pro.4334] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 05/02/2022] [Accepted: 05/03/2022] [Indexed: 12/28/2022]
Abstract
Human androgen receptor contains a large N‐terminal domain (AR‐NTD) that is highly dynamic and this poses a major challenge for experimental and computational analysis to decipher its conformation. Misfolding of the AR‐NTD is implicated in prostate cancer and Kennedy's disease, yet our knowledge of its structure is limited to primary sequence information of the chain and a few functionally important secondary structure motifs. Here, we employed an innovative combination of molecular dynamics simulations and circuit topology (CT) analysis to identify the tertiary structure of AR‐NTD. We found that the AR‐NTD adopts highly dynamic loopy conformations with two identifiable regions with distinct topological make‐up and dynamics. This consists of a N‐terminal region (NR, residues 1–224) and a C‐terminal region (CR, residues 225–538), which carries a dense core. Topological mapping of the dynamics reveals a traceable time‐scale dependent topological evolution. NR adopts different positioning with respect to the CR and forms a cleft that can partly enclose the hormone‐bound ligand‐binding domain (LBD) of the androgen receptor. Furthermore, our data suggest a model in which dynamic NR and CR compete for binding to the DNA‐binding domain of the receptor, thereby regulating the accessibility of its DNA‐binding site. Our approach allowed for the identification of a previously unknown regulatory binding site within the CR core, revealing the structural mechanisms of action of AR inhibitor EPI‐001, and paving the way for other drug discovery applications.
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Affiliation(s)
- Vahid Sheikhhassani
- Medical Systems Biophysics and Bioengineering, Leiden Academic Centre for Drug Research, Faculty of Science Leiden University Leiden The Netherlands
- Centre for Interdisciplinary Genome Research, Faculty of Science Leiden University Leiden The Netherlands
| | - Barbara Scalvini
- Medical Systems Biophysics and Bioengineering, Leiden Academic Centre for Drug Research, Faculty of Science Leiden University Leiden The Netherlands
- Centre for Interdisciplinary Genome Research, Faculty of Science Leiden University Leiden The Netherlands
| | - Julian Ng
- Medical Systems Biophysics and Bioengineering, Leiden Academic Centre for Drug Research, Faculty of Science Leiden University Leiden The Netherlands
- Centre for Interdisciplinary Genome Research, Faculty of Science Leiden University Leiden The Netherlands
| | - Laurens W. H. J. Heling
- Medical Systems Biophysics and Bioengineering, Leiden Academic Centre for Drug Research, Faculty of Science Leiden University Leiden The Netherlands
- Centre for Interdisciplinary Genome Research, Faculty of Science Leiden University Leiden The Netherlands
| | - Yosri Ayache
- Medical Systems Biophysics and Bioengineering, Leiden Academic Centre for Drug Research, Faculty of Science Leiden University Leiden The Netherlands
- Centre for Interdisciplinary Genome Research, Faculty of Science Leiden University Leiden The Netherlands
| | - Tom M. J. Evers
- Medical Systems Biophysics and Bioengineering, Leiden Academic Centre for Drug Research, Faculty of Science Leiden University Leiden The Netherlands
- Centre for Interdisciplinary Genome Research, Faculty of Science Leiden University Leiden The Netherlands
| | - Eva Estébanez‐Perpiñá
- Department of Biochemistry and Molecular Biomedicine Institute of Biomedicine (IBUB) of the University of Barcelona (UB) Barcelona Spain
| | - Iain J. McEwan
- Institute of Medical Sciences, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen Scotland UK
| | - Alireza Mashaghi
- Medical Systems Biophysics and Bioengineering, Leiden Academic Centre for Drug Research, Faculty of Science Leiden University Leiden The Netherlands
- Centre for Interdisciplinary Genome Research, Faculty of Science Leiden University Leiden The Netherlands
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11
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Kuznik NC, Solozobova V, Lee II, Jung N, Yang L, Nienhaus K, Ntim EA, Rottenberg JT, Muhle-Goll C, Kumar AR, Peravali R, Gräßle S, Gourain V, Deville C, Cato L, Neeb A, Dilger M, Cramer von Clausbruch CA, Weiss C, Kieffer B, Nienhaus GU, Brown M, Bräse S, Cato ACB. A chemical probe for BAG1 targets androgen receptor-positive prostate cancer through oxidative stress signaling pathway. iScience 2022; 25:104175. [PMID: 35479411 PMCID: PMC9036123 DOI: 10.1016/j.isci.2022.104175] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 03/01/2022] [Accepted: 03/25/2022] [Indexed: 11/16/2022] Open
Abstract
BAG1 is a family of polypeptides with a conserved C-terminal BAG domain that functions as a nucleotide exchange factor for the molecular chaperone HSP70. BAG1 proteins also control several signaling processes including proteostasis, apoptosis, and transcription. The largest isoform, BAG1L, controls the activity of the androgen receptor (AR) and is upregulated in prostate cancer. Here, we show that BAG1L regulates AR dynamics in the nucleus and its ablation attenuates AR target gene expression especially those involved in oxidative stress and metabolism. We show that a small molecule, A4B17, that targets the BAG domain downregulates AR target genes similar to a complete BAG1L knockout and upregulates the expression of oxidative stress-induced genes involved in cell death. Furthermore, A4B17 outperformed the clinically approved antagonist enzalutamide in inhibiting cell proliferation and prostate tumor development in a mouse xenograft model. BAG1 inhibitors therefore offer unique opportunities for antagonizing AR action and prostate cancer growth. BAG1L interacts with a sequence overlapping a polyalanine tract in the AR NTD Knockdown of BAG1L increase AR dynamics in the nucleus BAG1L uses ROS pathway to regulate AR+ prostate cancer cell proliferation A small molecule BAG1 inhibitor inhibits prostate tumor growth in mouse xenografts
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Affiliation(s)
- Nane C Kuznik
- Institute of Biological and Chemical Systems, Biological Information Processing, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Valeria Solozobova
- Institute of Biological and Chemical Systems, Biological Information Processing, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Irene I Lee
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
- Center for Functional Cancer Epigenetics, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | - Nicole Jung
- Institute of Biological and Chemical Systems, Functional Molecular Systems, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Linxiao Yang
- Institute of Applied Physics, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Karin Nienhaus
- Institute of Applied Physics, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Emmanuel A Ntim
- Institute of Biological and Chemical Systems, Biological Information Processing, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Jaice T Rottenberg
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
- Center for Functional Cancer Epigenetics, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | - Claudia Muhle-Goll
- Institute of Biological Interfaces 4, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
- Institute of Organic Chemistry, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Amrish Rajendra Kumar
- Institute of Biological and Chemical Systems, Biological Information Processing, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Ravindra Peravali
- Institute of Biological and Chemical Systems, Biological Information Processing, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Simone Gräßle
- Institute of Biological and Chemical Systems, Functional Molecular Systems, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Victor Gourain
- LabEx IGO "Immunotherapy, Graft, Oncology", Centre de Recherche en Transplantation et Immunologie - UMR1064, 44093 Nantes, France
| | - Célia Deville
- Department of Integrative Structural Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire, INSERM, U964, CNRS, UMR-7104, Université de Strasbourg, 67404 Illkirch-Graffenstaden, France
| | - Laura Cato
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
- Center for Functional Cancer Epigenetics, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | - Antje Neeb
- Institute of Biological and Chemical Systems, Biological Information Processing, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Marco Dilger
- Institute of Biological and Chemical Systems, Biological Information Processing, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Christina A Cramer von Clausbruch
- Institute of Biological and Chemical Systems, Biological Information Processing, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Carsten Weiss
- Institute of Biological and Chemical Systems, Biological Information Processing, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Bruno Kieffer
- Department of Integrative Structural Biology, Institut de Génétique et de Biologie Moléculaire et Cellulaire, INSERM, U964, CNRS, UMR-7104, Université de Strasbourg, 67404 Illkirch-Graffenstaden, France
| | - G Ulrich Nienhaus
- Institute of Biological and Chemical Systems, Biological Information Processing, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
- Institute of Applied Physics, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Myles Brown
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
- Center for Functional Cancer Epigenetics, Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | - Stefan Bräse
- Institute of Biological and Chemical Systems, Functional Molecular Systems, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
- Institute of Organic Chemistry, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Andrew C B Cato
- Institute of Biological and Chemical Systems, Biological Information Processing, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
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12
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Monaghan AE, Porter A, Hunter I, Morrison A, McElroy SP, McEwan IJ. Development of a High-Throughput Screening Assay for Small-Molecule Inhibitors of Androgen Receptor Splice Variants. Assay Drug Dev Technol 2022; 20:111-124. [PMID: 35333596 PMCID: PMC9057896 DOI: 10.1089/adt.2021.128] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The role of the androgen receptor (AR) in the progression of prostate cancer (PCa) is well established and competitive inhibition of AR ligand binding domain (LBD) has been the mainstay of antiandrogen therapies for advanced and metastatic disease. However, the efficacy of such drugs is often limited by the emergence of resistance, mediated through point mutations and receptor splice variants lacking the AR-LBD. As a result, the prognosis for patients with malignant, castrate-resistant disease remains poor. The amino terminal domain (NTD) of the AR has been shown to be critical for AR function. Its modular activation function (AF-1) is important for both gene regulation and participation in protein–protein interactions. However, due to the intrinsically disordered structure of the domain, its potential as a candidate for therapeutic intervention has been generally overlooked. In this article, we describe the design and development of a functional cell-based assay aimed at identifying small-molecule inhibitors of the AR-NTD. We demonstrate the suitability of the assay for high-throughput screening platforms and validate two initial hits emerging from a small, targeted, library screen in PCa cells.
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Affiliation(s)
- Amy E. Monaghan
- Institute of Medical Sciences, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, United Kingdom
| | - Alison Porter
- European Screening Centre (ESC), University of Dundee, Lanarkshire, United Kingdom
| | - Irene. Hunter
- Institute of Medical Sciences, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, United Kingdom
| | - Angus Morrison
- European Screening Centre (ESC), University of Dundee, Lanarkshire, United Kingdom
| | - Stuart P. McElroy
- European Screening Centre (ESC), University of Dundee, Lanarkshire, United Kingdom
| | - Iain J. McEwan
- Institute of Medical Sciences, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, United Kingdom
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13
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Dahiya UR, Heemers HV. Analyzing the Androgen Receptor Interactome in Prostate Cancer: Implications for Therapeutic Intervention. Cells 2022; 11:cells11060936. [PMID: 35326387 PMCID: PMC8946651 DOI: 10.3390/cells11060936] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 03/02/2022] [Accepted: 03/04/2022] [Indexed: 12/29/2022] Open
Abstract
The androgen receptor (AR) is a member of the ligand-activated nuclear receptor family of transcription factors. AR’s transactivation activity is turned on by the binding of androgens, the male sex steroid hormones. AR is critical for the development and maintenance of the male phenotype but has been recognized to also play an important role in human diseases. Most notably, AR is a major driver of prostate cancer (CaP) progression, which remains the second leading cause of cancer deaths in American men. Androgen deprivation therapies (ADTs) that interfere with interactions between AR and its activating androgen ligands have been the mainstay for treatment of metastatic CaP. Although ADTs are effective and induce remissions, eventually they fail, while the growth of the majority of ADT-resistant CaPs remains under AR’s control. Alternative approaches to inhibit AR activity and bypass resistance to ADT are being sought, such as preventing the interaction between AR and its cofactors and coregulators that is needed to execute AR-dependent transcription. For such strategies to be efficient, the 3D conformation of AR complexes needs to be well-understood and AR-regulator interaction sites resolved. Here, we review current insights into these 3D structures and the protein interaction sites in AR transcriptional complexes. We focus on methods and technological approaches used to identify AR interactors and discuss challenges and limitations that need to be overcome for efficient therapeutic AR complex disruption.
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14
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Roggero CM, Esser V, Duan L, Rice AM, Ma S, Raj GV, Rosen MK, Liu ZP, Rizo J. Poly-glutamine-dependent self-association as a potential mechanism for regulation of androgen receptor activity. PLoS One 2022; 17:e0258876. [PMID: 34986150 PMCID: PMC8730435 DOI: 10.1371/journal.pone.0258876] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 12/13/2021] [Indexed: 01/01/2023] Open
Abstract
The androgen receptor (AR) plays a central role in prostate cancer. Development of castration resistant prostate cancer (CRPC) requires androgen-independent activation of AR, which involves its large N-terminal domain (NTD) and entails extensive epigenetic changes depending in part on histone lysine demethylases (KDMs) that interact with AR. The AR-NTD is rich in low-complexity sequences, including a polyQ repeat. Longer polyQ sequences were reported to decrease transcriptional activity and to protect against prostate cancer, although they can lead to muscular atrophy. However, the molecular mechanisms underlying these observations are unclear. Using NMR spectroscopy, here we identify weak interactions between the AR-NTD and the KDM4A catalytic domain, and between the AR ligand-binding domain and a central KDM4A region that also contains low-complexity sequences. We also show that the AR-NTD can undergo liquid-liquid phase separation in vitro, with longer polyQ sequences phase separating more readily. Moreover, longer polyQ sequences hinder nuclear localization in the absence of hormone and increase the propensity for formation of AR-containing puncta in the nucleus of cells treated with dihydrotestosterone. These results lead us to hypothesize that polyQ-dependent liquid-liquid phase separation may provide a mechanism to decrease the transcriptional activity of AR, potentially opening new opportunities to design effective therapies against CRPC and muscular atrophy.
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Affiliation(s)
- Carlos M. Roggero
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Victoria Esser
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Lingling Duan
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Allyson M. Rice
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Shihong Ma
- Department of Urology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Ganesh V. Raj
- Department of Urology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Michael K. Rosen
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Zhi-Ping Liu
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Josep Rizo
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
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15
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Somatic Alterations Impact AR Transcriptional Activity and Efficacy of AR-Targeting Therapies in Prostate Cancer. Cancers (Basel) 2021; 13:cancers13163947. [PMID: 34439101 PMCID: PMC8393938 DOI: 10.3390/cancers13163947] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 07/31/2021] [Accepted: 08/02/2021] [Indexed: 12/26/2022] Open
Abstract
Simple Summary For patients whose prostate cancer spreads beyond the confines of the prostate, treatment options continue to increase. However, we are missing the information that is needed to choose for each patient the best treatment at each step of his cancer progression so we can ensure that maximal remissions and prolonged survival are achieved. In this review, we examine whether a better understanding of how the activity of the target for the default first treatment, the androgen receptor, is regulated in prostate cancer tissues can improve prostate cancer treatment plans. We consider the evidence for variability of androgen receptor activity among patients and examine the molecular basis for this variable action. We summarize clinical evidence supporting that information on a prostate cancer’s genomic composition may inform on its level of androgen receptor action, which may facilitate choice for the most effective first-line therapy and ultimately improve prostate cancer treatment plans overall. Abstract Inhibiting the activity of the ligand-activated transcription factor androgen receptor (AR) is the default first-line treatment for metastatic prostate cancer (CaP). Androgen deprivation therapy (ADT) induces remissions, however, their duration varies widely among patients. The reason for this heterogeneity is not known. A better understanding of its molecular basis may improve treatment plans and patient survival. AR’s transcriptional activity is regulated in a context-dependent manner and relies on an interplay between its associated transcriptional regulators, DNA recognition motifs, and ligands. Alterations in one or more of these factors induce shifts in the AR cistrome and transcriptional output. Significant variability in AR activity is seen in both castration-sensitive (CS) and castration-resistant CaP (CRPC). Several AR transcriptional regulators undergo somatic alterations that impact their function in clinical CaPs. Some alterations occur in a significant fraction of cases, resulting in CaP subtypes, while others affect only a few percent of CaPs. Evidence is emerging that these alterations may impact the response to CaP treatments such as ADT, radiation therapy, and chemotherapy. Here, we review the contribution of recurring somatic alterations on AR cistrome and transcriptional output and the efficacy of CaP treatments and explore strategies to use these insights to improve treatment plans and outcomes for CaP patients.
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16
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Kumar R. Role of conformational dynamics and flexibilities in the steroid receptor-coregulator protein complex formation. Gen Comp Endocrinol 2021; 309:113780. [PMID: 33882296 DOI: 10.1016/j.ygcen.2021.113780] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 03/21/2021] [Accepted: 04/09/2021] [Indexed: 10/21/2022]
Abstract
Understanding of the mechanisms of actions of the steroid hormone receptor (SHR)-coregulator (CoR) protein complexes in the gene regulations has revolutionized the field of molecular endocrinology and endocrine-related oncology. The discovery and characterization of steroid receptor coactivators (SRCs) and their ability to bind various transcription factors including SHRs to coordinate the regulation of multiple target genes highlights their importance as key coregulators in various cellular signaling crosstalks as well as therapeutic target for various endocrine-related disorders specifically endocrine cancers. The dynamic nature of the SHR-CoR multi-protein complexes indicate the critical role of conformational flexibilities within specific protein(s). In recent years, the importance of conformational dynamics of the SHRs in the intramolecular and intermolecular allosteric regulations mediated via their intrinsically disordered (ID) surfaces has been highlighted. In this review article, we have discussed the importance of ID conformations within the SRCs that may also be playing an important role in the formation/deformation of multi protein complexes involving SHRs and CoRs and subsequent target gene regulation.
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Affiliation(s)
- Raj Kumar
- Department of Biomedical Sciences, University of Houston - College of Medicine, Houston, TX, United States.
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17
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An Overview of Next-Generation Androgen Receptor-Targeted Therapeutics in Development for the Treatment of Prostate Cancer. Int J Mol Sci 2021; 22:ijms22042124. [PMID: 33672769 PMCID: PMC7924596 DOI: 10.3390/ijms22042124] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 02/17/2021] [Accepted: 02/17/2021] [Indexed: 12/31/2022] Open
Abstract
Traditional endocrine therapy for prostate cancer (PCa) has been directed at suppression of the androgen receptor (AR) signaling axis since Huggins et al. discovered that diethylstilbestrol (DES; an estrogen) produced chemical castration and PCa tumor regression. Androgen deprivation therapy (ADT) still remains the first-line PCa therapy. Insufficiency of ADT over time leads to castration-resistant PCa (CRPC) in which the AR axis is still active, despite castrate levels of circulating androgens. Despite the approval and use of multiple generations of competitive AR antagonists (antiandrogens), antiandrogen resistance emerges rapidly in CRPC due to several mechanisms, mostly converging in the AR axis. Recent evidence from multiple groups have defined noncompetitive or noncanonical direct binding sites on AR that can be targeted to inhibit the AR axis. This review discusses new developments in the PCa treatment paradigm that includes the next-generation molecules to noncanonical sites, proteolysis targeting chimera (PROTAC), or noncanonical N-terminal domain (NTD)-binding of selective AR degraders (SARDs). A few lead compounds targeting each of these novel noncanonical sites or with SARD activity are discussed. Many of these ligands are still in preclinical development, and a few early clinical leads have emerged, but successful late-stage clinical data are still lacking. The breadth and diversity of targets provide hope that optimized noncanonical inhibitors and/or SARDs will be able to overcome antiandrogen-resistant CRPC.
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18
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Eighty Years of Targeting Androgen Receptor Activity in Prostate Cancer: The Fight Goes on. Cancers (Basel) 2021; 13:cancers13030509. [PMID: 33572755 PMCID: PMC7865914 DOI: 10.3390/cancers13030509] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/25/2021] [Accepted: 01/25/2021] [Indexed: 12/24/2022] Open
Abstract
Simple Summary Prostate cancer is the second most common cancer in men world-wide, with nearly 1.3 million new cases each year, and over the next twenty years the incidence and death rate are predicted to nearly double. For decades, this lethal disease has been more or less successfully treated using hormonal therapy, which has the ultimate aim of inhibiting androgen signalling. However, prostate tumours can evade such hormonal therapies in a number of different ways and therapy resistant disease, so-called castration-resistant prostate cancer (CRPC) is the major clinical problem. Somewhat counterintuitively, the androgen receptor remains a key therapy target in CRPC. Here, we explain why this is the case and summarise both new hormone therapy strategies and the recent advances in knowledge of androgen receptor structure and function that underpin them. Abstract Prostate cancer (PCa) is the most common cancer in men in the West, other than skin cancer, accounting for over a quarter of cancer diagnoses in US men. In a seminal paper from 1941, Huggins and Hodges demonstrated that prostate tumours and metastatic disease were sensitive to the presence or absence of androgenic hormones. The first hormonal therapy for PCa was thus castration. In the subsequent eighty years, targeting the androgen signalling axis, where possible using drugs rather than surgery, has been a mainstay in the treatment of advanced and metastatic disease. Androgens signal via the androgen receptor, a ligand-activated transcription factor, which is the direct target of many such drugs. In this review we discuss the role of the androgen receptor in PCa and how the combination of structural information and functional screenings is continuing to be used for the discovery of new drug to switch off the receptor or modify its function in cancer cells.
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19
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Richters A, Doyle SK, Freeman DB, Lee C, Leifer BS, Jagannathan S, Kabinger F, Koren JV, Struntz NB, Urgiles J, Stagg RA, Curtin BH, Chatterjee D, Mathea S, Mikochik PJ, Hopkins TD, Gao H, Branch JR, Xin H, Westover L, Bignan GC, Rupnow BA, Karlin KL, Olson CM, Westbrook TF, Vacca J, Wilfong CM, Trotter BW, Saffran DC, Bischofberger N, Knapp S, Russo JW, Hickson I, Bischoff JR, Gottardis MM, Balk SP, Lin CY, Pop MS, Koehler AN. Modulating Androgen Receptor-Driven Transcription in Prostate Cancer with Selective CDK9 Inhibitors. Cell Chem Biol 2020; 28:134-147.e14. [PMID: 33086052 DOI: 10.1016/j.chembiol.2020.10.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/28/2020] [Accepted: 09/30/2020] [Indexed: 12/13/2022]
Abstract
Castration-resistant prostate cancers (CRPCs) lose sensitivity to androgen-deprivation therapies but frequently remain dependent on oncogenic transcription driven by the androgen receptor (AR) and its splice variants. To discover modulators of AR-variant activity, we used a lysate-based small-molecule microarray assay and identified KI-ARv-03 as an AR-variant complex binder that reduces AR-driven transcription and proliferation in prostate cancer cells. We deduced KI-ARv-03 to be a potent, selective inhibitor of CDK9, an important cofactor for AR, MYC, and other oncogenic transcription factors. Further optimization resulted in KB-0742, an orally bioavailable, selective CDK9 inhibitor with potent anti-tumor activity in CRPC models. In 22Rv1 cells, KB-0742 rapidly downregulates nascent transcription, preferentially depleting short half-life transcripts and AR-driven oncogenic programs. In vivo, oral administration of KB-0742 significantly reduced tumor growth in CRPC, supporting CDK9 inhibition as a promising therapeutic strategy to target AR dependence in CRPC.
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Affiliation(s)
- André Richters
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; MIT Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Shelby K Doyle
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; MIT Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | | | | | - Becky S Leifer
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; MIT Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Sajjeev Jagannathan
- Therapeutic Innovation Center, Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Florian Kabinger
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; MIT Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Jošt Vrabič Koren
- Therapeutic Innovation Center, Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Nicholas B Struntz
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; MIT Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Julie Urgiles
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Harvard-MIT Health Sciences and Technology, Boston, MA 02115, USA
| | - Ryan A Stagg
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Department of Biology, Boston University, Boston, MA 02215, USA
| | - Brice H Curtin
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; MIT Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Deep Chatterjee
- Goethe-Universität Frankfurt, 60438 Frankfurt am Main, Germany
| | | | | | | | - Hua Gao
- Kronos Bio, Inc., Cambridge, MA 02139, USA
| | | | - Hong Xin
- Janssen Research & Development, LLC, Spring House, PA, USA
| | - Lori Westover
- Janssen Research & Development, LLC, Spring House, PA, USA
| | | | - Brent A Rupnow
- Janssen Research & Development, LLC, Spring House, PA, USA
| | - Kristen L Karlin
- Therapeutic Innovation Center, Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Calla M Olson
- Therapeutic Innovation Center, Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Thomas F Westbrook
- Therapeutic Innovation Center, Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | | | | | | | | | | | - Stefan Knapp
- Goethe-Universität Frankfurt, 60438 Frankfurt am Main, Germany
| | - Joshua W Russo
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Ian Hickson
- Janssen Research & Development, LLC, Spring House, PA, USA; Cancer Research UK Newcastle Drug Discovery Unit, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | | | | | - Steven P Balk
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Charles Y Lin
- Kronos Bio, Inc., Cambridge, MA 02139, USA; Therapeutic Innovation Center, Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | | | - Angela N Koehler
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; MIT Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA 02142, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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20
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Baumgart SJ, Nevedomskaya E, Lesche R, Newman R, Mumberg D, Haendler B. Darolutamide antagonizes androgen signaling by blocking enhancer and super-enhancer activation. Mol Oncol 2020; 14:2022-2039. [PMID: 32333502 PMCID: PMC7463324 DOI: 10.1002/1878-0261.12693] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 04/03/2020] [Accepted: 04/22/2020] [Indexed: 02/06/2023] Open
Abstract
Prostate cancer (PCa) is one of the most frequent tumor types in the male Western population. Early-stage PCa and late-stage PCa are dependent on androgen signaling, and inhibitors of the androgen receptor (AR) axis represent the standard therapy. Here, we studied in detail the global impact of darolutamide, a newly approved AR antagonist, on the transcriptome and AR-bound cistrome in two PCa cell models. Darolutamide strongly depleted the AR from gene regulatory regions and abolished AR-driven transcriptional signaling. Enhancer activation was blocked at the chromatin level as evaluated by H3K27 acetylation (H3K27ac), H3K4 monomethylation (H3K4me1), and FOXA1, MED1, and BRD4 binding. We identified genomic regions with high affinities for the AR in androgen-stimulated, but also in androgen-depleted conditions. A similar AR affinity pattern was observed in healthy and PCa tissue samples. High FOXA1, BRD4, H3K27ac, and H3K4me1 levels were found to mark regions showing AR binding in the hormone-depleted setting. Conversely, low FOXA1, BRD4, and H3K27ac levels were observed at regulatory sites that responded strongly to androgen stimulation, and AR interactions at these sites were blocked by darolutamide. Beside marked loss of AR occupancy, FOXA1 recruitment to chromatin was also clearly reduced after darolutamide treatment. We furthermore identified numerous androgen-regulated super-enhancers (SEs) that were associated with hallmark androgen and cell proliferation-associated gene sets. Importantly, these SEs are also active in PCa tissues and sensitive to darolutamide treatment in our models. Our findings demonstrate that darolutamide is a potent AR antagonist blocking genome-wide AR enhancer and SE activation, and downstream transcription. We also show the existence of a dynamic AR cistrome that depends on the androgen levels and on high AR affinity regions present in PCa cell lines and also in tissue samples.
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Affiliation(s)
| | | | - Ralf Lesche
- Research and Development, PharmaceuticalsBayer AGBerlinGermany
| | - Richard Newman
- Research and Development, PharmaceuticalsBayer AGBerlinGermany
| | - Dominik Mumberg
- Research and Development, PharmaceuticalsBayer AGBerlinGermany
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21
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Regression of castration-resistant prostate cancer by a novel compound QW07 targeting androgen receptor N-terminal domain. Cell Biol Toxicol 2020; 36:399-416. [PMID: 32002708 DOI: 10.1007/s10565-020-09511-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 01/07/2020] [Indexed: 12/24/2022]
Abstract
Androgen deprivation therapy (ADT) via surgical or chemical castration frequently fails to halt lethal castration-resistant prostate cancer (CRPC), which is induced by multiple mechanisms involving constitutive androgen receptor (AR) splice variants, AR mutation, and/or de novo androgen synthesis. The AR N-terminal domain (NTD) possesses most transcriptional activity and is proposed as a potential target for CRPC drug development. We constructed a screening system targeting AR-NTD transcription activity to screening a compound library and identified a novel small molecule compound named QW07. The function evaluation and mechanism investigation of QW07 were carried out in vitro and in vivo. QW07 bound to AR-NTD directly, blocked the transactivation of AR-NTD, blocked interactions between co-regulatory proteins and androgen response elements (AREs), inhibited the expression of genes downstream of AR, and inhibited prostate cancer growth in vitro and in vivo. QW07 was demonstrated as an AR-NTD-specific antagonist with the potential to inhibit both canonical and variant-mediated AR signaling to regress the CRPC xenografts and is proposed as a lead compound for a specific antagonist targeting AR-NTD.
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22
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Obst JK, Wang J, Jian K, Williams DE, Tien AH, Mawji N, Tam T, Yang YC, Andersen RJ, Chi KN, Montgomery B, Sadar MD. Revealing Metabolic Liabilities of Ralaniten To Enhance Novel Androgen Receptor Targeted Therapies. ACS Pharmacol Transl Sci 2019; 2:453-467. [PMID: 32259077 PMCID: PMC7088963 DOI: 10.1021/acsptsci.9b00065] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Indexed: 12/15/2022]
Abstract
Inhibition of the androgen receptor (AR) is the mainstay treatment for advanced prostate cancer. Ralaniten (formally EPI-002) prevents AR transcriptional activity by binding to its N-terminal domain (NTD) which is essential for transcriptional activity. Ralaniten acetate (EPI-506) the triacetate pro-drug of ralaniten, remains the only AR-NTD inhibitor to have entered clinical trials (NCT02606123). While well tolerated, the trial was ultimately terminated due to poor pharmacokinetic properties and resulting pill burden. Here we discovered that ralaniten was glucuronidated which resulted in decreased potency. Long-term treatment of prostate cancer cells with ralaniten results in upregulation of UGT2B enzymes with concomitant loss of potency. This has proven to be a useful model with which to facilitate the development of more potent second-generation AR-NTD inhibitors. Glucuronidated metabolites of ralaniten were also detected in the serum of patients in Phase 1 clinical trials. Therefore, we tested an analogue of ralaniten (EPI-045) which was resistant to glucuronidation and demonstrated superiority to ralaniten in our resistant model. These data support that analogues of ralaniten designed to mitigate glucuronidation may optimize clinical responses to AR-NTD inhibitors.
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Affiliation(s)
- Jon K. Obst
- Department
of Genome Sciences Centre, BC Cancer Research
Centre, 675 W 10th Avenue, Vancouver, British Columbia V5Z 1L3, Canada
- Department
of Pathology and Laboratory Medicine, University
of British Columbia, 2211 Westbrook Mall, Vancouver, British Columbia V6T 2B5, Canada
| | - Jun Wang
- Department
of Genome Sciences Centre, BC Cancer Research
Centre, 675 W 10th Avenue, Vancouver, British Columbia V5Z 1L3, Canada
| | - Kunzhong Jian
- Departments
of Chemistry and Earth, Ocean & Atmospheric Sciences, University of British Columbia, 2306 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
| | - David E. Williams
- Departments
of Chemistry and Earth, Ocean & Atmospheric Sciences, University of British Columbia, 2306 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
| | - Amy H. Tien
- Department
of Genome Sciences Centre, BC Cancer Research
Centre, 675 W 10th Avenue, Vancouver, British Columbia V5Z 1L3, Canada
| | - Nasrin Mawji
- Department
of Genome Sciences Centre, BC Cancer Research
Centre, 675 W 10th Avenue, Vancouver, British Columbia V5Z 1L3, Canada
| | - Teresa Tam
- Department
of Genome Sciences Centre, BC Cancer Research
Centre, 675 W 10th Avenue, Vancouver, British Columbia V5Z 1L3, Canada
| | - Yu Chi Yang
- Department
of Genome Sciences Centre, BC Cancer Research
Centre, 675 W 10th Avenue, Vancouver, British Columbia V5Z 1L3, Canada
| | - Raymond J. Andersen
- Departments
of Chemistry and Earth, Ocean & Atmospheric Sciences, University of British Columbia, 2306 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada
| | - Kim N. Chi
- BC
Cancer Agency, 600 West
10th Avenue, Vancouver, British
Columbia V5Z 4E6, Canada
| | - Bruce Montgomery
- University
of Washington, 1959 NE Pacific Street, Seattle, Washington 98195, United States
| | - Marianne D. Sadar
- Department
of Genome Sciences Centre, BC Cancer Research
Centre, 675 W 10th Avenue, Vancouver, British Columbia V5Z 1L3, Canada
- Department
of Pathology and Laboratory Medicine, University
of British Columbia, 2211 Westbrook Mall, Vancouver, British Columbia V6T 2B5, Canada
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23
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Su B, Zhang L, Liu S, Chen X, Zhang W. GABARAPL1 Promotes AR+ Prostate Cancer Growth by Increasing FL-AR/AR-V Transcription Activity and Nuclear Translocation. Front Oncol 2019; 9:1254. [PMID: 31803623 PMCID: PMC6872515 DOI: 10.3389/fonc.2019.01254] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 10/30/2019] [Indexed: 12/19/2022] Open
Abstract
The next generation Androgen receptor (AR)-targeted therapies are now in widespread clinical use and prolong prostate cancer (CaP) patient survival. However, the therapies are not curative due to diverse range of resistance mechanisms. AR variants (AR-V), one major mechanism of resistance, has recently gained momentum. Here, we found that GABARAPL1 knockdown inhibits the growth of AR-positive LNCaP and CWR22rv1 CaP cells in vitro and in vivo, decreases AR/AR-V transcription activity and AR nuclear translocation. Pulldown assay shows that both of Full-length (FL)-AR and AR-V were able to interact with GABARAPL1, suggesting that GABARAPL1 may play its role through directly scaffolding AR. The further analysis from Oncomine database showed that negative correlation between GABARAPL1 expression and 5-years survival in CaP cases. Our findings have identified GABARAPL1 as critical regulator of FL-AR/AR-V, suggesting the potential benefit of targeting GABARAPL1 to treat AR-positive CaP that is resistant to next generation AR inhibitors.
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Affiliation(s)
- Bing Su
- Xinxiang Key Lab of Translational Cancer Research, The Third Affiliated Hospital, Xinxiang Medical University, Xinxiang, China
| | - Lijuan Zhang
- Xinxiang Key Lab of Translational Cancer Research, The Third Affiliated Hospital, Xinxiang Medical University, Xinxiang, China
| | - Shenglin Liu
- Biomedical Research Institute, Shenzhen Peking University - The Hong Kong University of Science and Technology Medical Center, Shenzhen, China
| | - Xiaofan Chen
- Biomedical Research Institute, Shenzhen Peking University - The Hong Kong University of Science and Technology Medical Center, Shenzhen, China
| | - Wei Zhang
- Biomedical Research Institute, Shenzhen Peking University - The Hong Kong University of Science and Technology Medical Center, Shenzhen, China
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24
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Zamagni A, Cortesi M, Zanoni M, Tesei A. Non-nuclear AR Signaling in Prostate Cancer. Front Chem 2019; 7:651. [PMID: 31616657 PMCID: PMC6775214 DOI: 10.3389/fchem.2019.00651] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 09/11/2019] [Indexed: 11/17/2022] Open
Abstract
Despite the key role played by androgen receptor (AR) in tumor cell aggressiveness and prostate cancer (PCa) progression, its function in the tumor microenvironment (TME) is still controversial. Increasing studies highlight the crucial role played by TME modulation in treatment outcome and tumor cell spreading. In this context, targeting specific constituents of the TME could be considered an alternative approach to classic treatments directed against cancer cells. Currently, androgen deprivation therapy (ADT) is a routinely adopted strategy in the management of PCa, with initial success, and consecutive fail. A possible justification to this is the fact that ADT aims to target all the transcription/translation-related activities of AR, which are typical of tumor epithelial cells. Less is still known about side effects of ADT on TME. Cancer Associated Fibroblasts (CAFs), for example, express a classic AR, mostly confined in the extra-nuclear portion of the cell. In CAFs ADT exerts a plethora of non-transcriptional effects, depending by the protein partner linked to AR, leading to cell migration, proliferation, and differentiation. In recent years, substantial progress in the structure-function relationships of AR, identification of its binding partners and function of protein complexes including AR have improved our knowledge of its signaling axis. Important AR non-genomic effects and lots of its cytoplasmatic binding partners have been described, pointing out a fine control of AR non-genomic pathways. Accordingly, new AR inhibitors have been designed and are currently under investigation. Prompt development of new approaches to target AR or block recruitment of its signaling effectors, or co-activators, is urgently needed. The present review takes an in-depth look at current literature, furnishing an exhaustive state-of-the-art overview of the non-genomic role of AR in PCa, with particular emphasis on its involvement in TME biology.
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Affiliation(s)
- Alice Zamagni
- Biosciences Laboratory, Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST), IRCCS, Meldola, Italy
| | - Michela Cortesi
- Biosciences Laboratory, Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST), IRCCS, Meldola, Italy
| | - Michele Zanoni
- Biosciences Laboratory, Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST), IRCCS, Meldola, Italy
| | - Anna Tesei
- Biosciences Laboratory, Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST), IRCCS, Meldola, Italy
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25
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Rosati R, Polin L, Ducker C, Li J, Bao X, Selvakumar D, Kim S, Xhabija B, Larsen M, McFall T, Huang Y, Kidder BL, Fribley A, Saxton J, Kakuta H, Shaw P, Ratnam M. Strategy for Tumor-Selective Disruption of Androgen Receptor Function in the Spectrum of Prostate Cancer. Clin Cancer Res 2018; 24:6509-6522. [PMID: 30185422 PMCID: PMC6295231 DOI: 10.1158/1078-0432.ccr-18-0982] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 08/03/2018] [Accepted: 08/31/2018] [Indexed: 11/16/2022]
Abstract
PURPOSE Testosterone suppression in prostate cancer is limited by serious side effects and resistance via restoration of androgen receptor (AR) functionality. ELK1 is required for AR-dependent growth in various hormone-dependent and castration-resistant prostate cancer models. The amino-terminal domain of AR docks at two sites on ELK1 to coactivate essential growth genes. This study explores the ability of small molecules to disrupt the ELK1-AR interaction in the spectrum of prostate cancer, inhibiting AR activity in a manner that would predict functional tumor selectivity. EXPERIMENTAL DESIGN Small-molecule drug discovery and extensive biological characterization of a lead compound. RESULTS We have discovered a lead molecule (KCI807) that selectively disrupts ELK1-dependent promoter activation by wild-type and variant ARs without interfering with ELK1 activation by ERK. KCI807 has an obligatory flavone scaffold and functional hydroxyl groups on C5 and C3'. KCI807 binds to AR, blocking ELK1 binding, and selectively blocks recruitment of AR to chromatin by ELK1. KCI807 primarily affects a subset of AR target growth genes selectively suppressing AR-dependent growth of prostate cancer cell lines with a better inhibitory profile than enzalutamide. KCI807 also inhibits in vivo growth of castration/enzalutamide-resistant cell line-derived and patient-derived tumor xenografts. In the rodent model, KCI807 has a plasma half-life of 6 hours, and maintenance of its antitumor effect is limited by self-induced metabolism at its 3'-hydroxyl. CONCLUSIONS The results offer a mechanism-based therapeutic paradigm for disrupting the AR growth-promoting axis in the spectrum of prostate tumors while reducing global suppression of testosterone actions. KCI807 offers a good lead molecule for drug development.
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Affiliation(s)
- Rayna Rosati
- Department of Oncology, Wayne State University School of Medicine and Barbara Ann Karmanos Cancer Institute, Detroit, Michigan
| | - Lisa Polin
- Department of Oncology, Wayne State University School of Medicine and Barbara Ann Karmanos Cancer Institute, Detroit, Michigan
| | - Charles Ducker
- School of Life Sciences, University of Nottingham, Queens Medical Centre, Nottingham, United Kingdom
| | - Jing Li
- Department of Oncology, Wayne State University School of Medicine and Barbara Ann Karmanos Cancer Institute, Detroit, Michigan
| | - Xun Bao
- Department of Oncology, Wayne State University School of Medicine and Barbara Ann Karmanos Cancer Institute, Detroit, Michigan
| | - Dakshnamurthy Selvakumar
- Department of Oncology, Wayne State University School of Medicine and Barbara Ann Karmanos Cancer Institute, Detroit, Michigan
| | - Seongho Kim
- Department of Oncology, Wayne State University School of Medicine and Barbara Ann Karmanos Cancer Institute, Detroit, Michigan
| | - Besa Xhabija
- Department of Oncology, Wayne State University School of Medicine and Barbara Ann Karmanos Cancer Institute, Detroit, Michigan
- Department of Chemistry and Biochemistry, University of Michigan-Flint, Flint, Michigan
| | - Martha Larsen
- University of Michigan, Life Sciences Institute and Center for Chemical Genomics, Ann Arbor, Michigan
| | - Thomas McFall
- Department of Oncology, Wayne State University School of Medicine and Barbara Ann Karmanos Cancer Institute, Detroit, Michigan
| | - Yanfang Huang
- Department of Oncology, Wayne State University School of Medicine and Barbara Ann Karmanos Cancer Institute, Detroit, Michigan
| | - Benjamin L Kidder
- Department of Oncology, Wayne State University School of Medicine and Barbara Ann Karmanos Cancer Institute, Detroit, Michigan
| | - Andrew Fribley
- Department of Pediatrics, Wayne State University School of Medicine and Barbara Ann Karmanos Cancer Institute, Detroit, Michigan
| | - Janice Saxton
- School of Life Sciences, University of Nottingham, Queens Medical Centre, Nottingham, United Kingdom
| | - Hiroki Kakuta
- Division of Pharmaceutical Sciences, Graduate School of Medicine, Okayama University, Okayama, Japan
| | - Peter Shaw
- School of Life Sciences, University of Nottingham, Queens Medical Centre, Nottingham, United Kingdom
| | - Manohar Ratnam
- Department of Oncology, Wayne State University School of Medicine and Barbara Ann Karmanos Cancer Institute, Detroit, Michigan.
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26
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Li D, Tian G, Wang J, Zhao LY, Co O, Underill ZC, Mymryk JS, Claessens F, Dehm SM, Daaka Y, Liao D. Inhibition of androgen receptor transactivation function by adenovirus type 12 E1A undermines prostate cancer cell survival. Prostate 2018; 78:1140-1156. [PMID: 30009471 PMCID: PMC6424568 DOI: 10.1002/pros.23689] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 06/26/2018] [Indexed: 12/12/2022]
Abstract
BACKGROUND Mutations or truncation of the ligand-binding domain (LBD) of androgen receptor (AR) underlie treatment resistance for prostate cancer (PCa). Thus, targeting the AR N-terminal domain (NTD) could overcome such resistance. METHODS Luciferase reporter assays after transient transfection of various DNA constructs were used to assess effects of E1A proteins on AR-mediated transcription. Immunofluorescence microscopy and subcellular fractionation were applied to assess intracellular protein localization. Immunoprecipitation and mammalian two-hybrid assays were used to detect protein-protein interactions. qRT-PCR was employed to determine RNA levels. Western blotting was used to detect protein expression in cells. Effects of adenoviruses on prostate cancer cell survival were evaluated with CellTiter-Glo assays. RESULTS Adenovirus 12 E1A (E1A12) binds specifically to the AR. Interestingly, the full-length E1A12 (266 aa) preferentially binds to full-length AR, while the small E1A12 variant (235 aa) interacts more strongly with AR-V7. E1A12 promotes AR nuclear translocation, likely through mediating intramolecular AR NTD-LBD interactions. In the nucleus, AR and E1A12 co-expression in AR-null PCa cells results in E1A12 redistribution from nuclear foci containing CBX4 (also known as Pc2), suggesting a preferential AR-E1A12 interaction over other E1A12 interactors. E1A12 represses AR-mediated transcription in reporter gene assays and endogenous AR target genes such as ATAD2 and MYC in AR-expressing PCa cells. AR-expressing PCa cells are more sensitive to death induced by a recombinant adenovirus expressing E1A12 (Ad-E1A12) than AR-deficient PCa cells, which could be attributed to the increased viral replication promoted by androgen stimulation. Targeting the AR by E1A12 promotes apoptosis in PCa cells that express the full-length AR or C-terminally truncated AR variants. Importantly, inhibition of mTOR signaling that blocks the expression of anti-apoptotic proteins markedly augments Ad-E1A12-induced apoptosis of AR-expressing cells. Mechanistically, Ad-E1A12 infection triggers apoptotic response while activating the PI3K-AKT-mTOR signaling axis; thus, mTOR inhibition enhances apoptosis in AR-expressing PCa cells infected by Ad-E1A12. CONCLUSION Ad12 E1A inhibits AR-mediated transcription and suppresses PCa cell survival, suggesting that targeting the AR by E1A12 might have therapeutic potential for treating advanced PCa with heightened AR signaling.
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Affiliation(s)
- Dawei Li
- Department of Urology, Qilu Hospital of Shandong University, 107 Wenhuaxi Road, Jinan, 250012, P. R. China
- Department of Anatomy and Cell Biology, UF Health Cancer Center and UF Genetics Institute, University of Florida College of Medicine, Gainesville, Florida 32610
| | - Guimei Tian
- Department of Anatomy and Cell Biology, UF Health Cancer Center and UF Genetics Institute, University of Florida College of Medicine, Gainesville, Florida 32610
| | - Jia Wang
- Department of Anatomy and Cell Biology, UF Health Cancer Center and UF Genetics Institute, University of Florida College of Medicine, Gainesville, Florida 32610
- Affiliated Dongzhimen Hospital, Beijing University of Chinese Medicine, Beijing, P. R. China
| | - Lisa Y. Zhao
- Department of Anatomy and Cell Biology, UF Health Cancer Center and UF Genetics Institute, University of Florida College of Medicine, Gainesville, Florida 32610
- Present address: Department of Medicine, University of Florida, Gainesville, FL 32610
| | - Olivia Co
- Department of Anatomy and Cell Biology, UF Health Cancer Center and UF Genetics Institute, University of Florida College of Medicine, Gainesville, Florida 32610
| | - Zoe C. Underill
- Department of Anatomy and Cell Biology, UF Health Cancer Center and UF Genetics Institute, University of Florida College of Medicine, Gainesville, Florida 32610
| | - Joe S. Mymryk
- Department of Microbiology and Immunology, the University of Western Ontario, London Regional Cancer Centre, Ontario, Canada
| | - Frank Claessens
- Laboratory of Molecular Endocrinology, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49 PO box 901, 3000 Leuven, Belgium
| | - Scott M. Dehm
- Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota 55455
| | - Yehia Daaka
- Department of Anatomy and Cell Biology, UF Health Cancer Center and UF Genetics Institute, University of Florida College of Medicine, Gainesville, Florida 32610
| | - Daiqing Liao
- Department of Anatomy and Cell Biology, UF Health Cancer Center and UF Genetics Institute, University of Florida College of Medicine, Gainesville, Florida 32610
- Corresponding author: Department of Anatomy and Cell Biology, University of Florida, 1333 Center Drive, Gainesville, Florida, 32610-0235, , Phone: 352-273-8188, Fax: 352-846-1248
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27
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Dong J, Wu Z, Wang D, Pascal LE, Nelson JB, Wipf P, Wang Z. Hsp70 Binds to the Androgen Receptor N-terminal Domain and Modulates the Receptor Function in Prostate Cancer Cells. Mol Cancer Ther 2018; 18:39-50. [PMID: 30297360 DOI: 10.1158/1535-7163.mct-18-0432] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 08/15/2018] [Accepted: 10/03/2018] [Indexed: 01/03/2023]
Abstract
The androgen receptor (AR) is a key driver and therapeutic target in androgen-sensitive prostate cancer, castration-resistant prostate cancer (CRPC), and CRPC resistant to abiraterone and enzalutamide, two second-generation inhibitors of AR signaling. Because current AR inhibitors target a functioning C-terminal ligand-binding domain (LBD), the identification and characterization of cofactors interacting with the N-terminal domain (NTD) of AR may lead to new approaches to target AR signaling in CRPC. Using a pull-down approach coupled with proteomics, we have identified Hsp70 as a cofactor for the NTD of AR in prostate cancer cells. Hsp70 inhibition using siRNA or small molecules indicated that Hsp70 played an important role in the expression and transactivation of endogenous AR. Prostate-specific antigen (PSA) promoter/enhancer-driven luciferase assays showed that Hsp70 was also required for transactivation of AR mutant lacking LBD. Furthermore, clonogenic assays showed that an Hsp70 inhibitor, either alone or in synergy with enzalutamide, can inhibit the proliferation of 22Rv1, a widely used enzalutamide-resistant CRPC prostate cancer cell line. These findings suggest that Hsp70 is a potential therapeutic target for the treatment of enzalutamide-resistant CRPC.
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Affiliation(s)
- Jun Dong
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.,Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zeyu Wu
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.,The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Dan Wang
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Laura E Pascal
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Joel B Nelson
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Peter Wipf
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania.,University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.,Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Zhou Wang
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania. .,University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.,Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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28
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daSilva LF, Beckedorff FC, Ayupe AC, Amaral MS, Mesel V, Videira A, Reis EM, Setubal JC, Verjovski-Almeida S. Chromatin Landscape Distinguishes the Genomic Loci of Hundreds of Androgen-Receptor-Associated LincRNAs From the Loci of Non-associated LincRNAs. Front Genet 2018; 9:132. [PMID: 29875794 PMCID: PMC5985396 DOI: 10.3389/fgene.2018.00132] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 04/03/2018] [Indexed: 11/30/2022] Open
Abstract
Cell signaling events triggered by androgen hormone in prostate cells is dependent on activation of the androgen receptor (AR) transcription factor. Androgen hormone binding to AR promotes its displacement from the cytoplasm to the nucleus and AR binding to DNA motifs, thus inducing activatory and inhibitory transcriptional programs through a complex regulatory mechanism not yet fully understood. In this work, we performed RNA-seq deep-sequencing of LNCaP prostate cancer cells and found over 7000 expressed long intergenic non-coding RNAs (lincRNAs), of which ∼4000 are novel lincRNAs, and 258 lincRNAs have their expression activated by androgen. Immunoprecipitation of AR, followed by large-scale sequencing of co-immunoprecipitated RNAs (RIP-Seq) has identified in the LNCaP cell line a total of 619 lincRNAs that were significantly enriched (FDR < 10%, DESeq2) in the anti-Androgen Receptor (antiAR) fraction in relation to the control fraction (non-specific IgG), and we named them Androgen-Receptor-Associated lincRNAs (ARA-lincRNAs). A genome-wide analysis showed that protein-coding gene neighbors to ARA-lincRNAs had a significantly higher androgen-induced change in expression than protein-coding genes neighboring lincRNAs not associated to AR. To find relevant epigenetic signatures enriched at the ARA-lincRNAs’ transcription start sites (TSSs) we used a machine learning approach and identified that the ARA-lincRNA genomic loci in LNCaP cells are significantly enriched with epigenetic marks that are characteristic of in cis enhancer RNA regulators, and that the H3K27ac mark of active enhancers is conspicuously enriched at the TSS of ARA-lincRNAs adjacent to androgen-activated protein-coding genes. In addition, LNCaP topologically associating domains (TADs) that comprise chromatin regions with ARA-lincRNAs exhibit transcription factor contents, epigenetic marks and gene transcriptional activities that are significantly different from TADs not containing ARA-lincRNAs. This work highlights the possible involvement of hundreds of lincRNAs working in synergy with the AR on the genome-wide androgen-induced gene regulatory program in prostate cells.
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Affiliation(s)
- Lucas F daSilva
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil.,Laboratório de Expressão Gênica em Eucariotos, Instituto Butantan, São Paulo, Brazil
| | - Felipe C Beckedorff
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil.,Laboratório de Expressão Gênica em Eucariotos, Instituto Butantan, São Paulo, Brazil
| | - Ana C Ayupe
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Murilo S Amaral
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil.,Laboratório de Expressão Gênica em Eucariotos, Instituto Butantan, São Paulo, Brazil
| | - Vinícius Mesel
- Laboratório de Expressão Gênica em Eucariotos, Instituto Butantan, São Paulo, Brazil
| | - Alexandre Videira
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil.,Laboratório de Expressão Gênica em Eucariotos, Instituto Butantan, São Paulo, Brazil
| | - Eduardo M Reis
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - João C Setubal
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil.,Biocomplexity Institute of Virginia Tech, Blacksburg, VA, United States
| | - Sergio Verjovski-Almeida
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil.,Laboratório de Expressão Gênica em Eucariotos, Instituto Butantan, São Paulo, Brazil
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29
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Jolly MK, Kulkarni P, Weninger K, Orban J, Levine H. Phenotypic Plasticity, Bet-Hedging, and Androgen Independence in Prostate Cancer: Role of Non-Genetic Heterogeneity. Front Oncol 2018; 8:50. [PMID: 29560343 PMCID: PMC5845637 DOI: 10.3389/fonc.2018.00050] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2017] [Accepted: 02/19/2018] [Indexed: 12/21/2022] Open
Abstract
It is well known that genetic mutations can drive drug resistance and lead to tumor relapse. Here, we focus on alternate mechanisms-those without mutations, such as phenotypic plasticity and stochastic cell-to-cell variability that can also evade drug attacks by giving rise to drug-tolerant persisters. The phenomenon of persistence has been well-studied in bacteria and has also recently garnered attention in cancer. We draw a parallel between bacterial persistence and resistance against androgen deprivation therapy in prostate cancer (PCa), the primary standard care for metastatic disease. We illustrate how phenotypic plasticity and consequent mutation-independent or non-genetic heterogeneity possibly driven by protein conformational dynamics can stochastically give rise to androgen independence in PCa, and suggest that dynamic phenotypic plasticity should be considered in devising therapeutic dosing strategies designed to treat and manage PCa.
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Affiliation(s)
- Mohit Kumar Jolly
- Center for Theoretical Biological Physics, Rice University, Houston, TX, United States
| | - Prakash Kulkarni
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD, United States
| | - Keith Weninger
- Department of Physics, North Carolina State University, Raleigh, NC, United States
| | - John Orban
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD, United States
- Department of Chemistry and Biochemistry, University of Maryland, College Park, College Park, United States
| | - Herbert Levine
- Center for Theoretical Biological Physics, Rice University, Houston, TX, United States
- Department of Bioengineering, Rice University, Houston, TX, United States
- Department of Physics and Astronomy, Rice University, Houston, TX, United States
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30
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Perera L, Li Y, Coons LA, Houtman R, van Beuningen R, Goodwin B, Auerbach SS, Teng CT. Binding of bisphenol A, bisphenol AF, and bisphenol S on the androgen receptor: Coregulator recruitment and stimulation of potential interaction sites. Toxicol In Vitro 2017; 44:287-302. [PMID: 28751236 DOI: 10.1016/j.tiv.2017.07.020] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 06/20/2017] [Accepted: 07/20/2017] [Indexed: 10/19/2022]
Abstract
Bisphenol A (BPA), bisphenol AF (BPAF), and bisphenol S (BPS) are well known endocrine disruptors. Previous in vitro studies showed that these compounds antagonize androgen receptor (AR) transcriptional activity; however, the mechanisms of action are unclear. In the present study, we investigated interactions of coregulator peptides with BPA, BPAF, or BPS at the AR complexes using Micro Array for Real-time Coregulator Nuclear Receptor Interaction (MARCoNI) assays and assessed the binding of these compounds on AR by molecular dynamics (MD) simulations. The set of coregulator peptides that are recruited by BPA-bound AR, either positively/or negatively, are different from those recruited by the agonist R1881-bound AR. Therefore, the data indicates that BPA shows no similarities to R1881 and suggests that it may recruit other coregulators to the AR complex. BPAF-bound AR recruits about 70-80% of the same coregulator peptides as BPA-bound AR. Meanwhile, BPS-bound AR interacts with only few peptides compared to BPA or BPAF-bound AR. MD results show that multiple binding sites with varying binding affinities are available on AR for BPA, BPAF, and BPS, indicating the availability of modified binding surfaces on AR for coregulator interactions. These findings help explain some of the distinct AR-related toxicities observed with bisphenol chemicals and raise concern for the use of substitutes for BPA in commercial products.
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Affiliation(s)
- Lalith Perera
- Genome Integrity and Structural Biology Laboratory, United States
| | - Yin Li
- Reproductive and Developmental Biology Laboratory, DIR, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, United States
| | - Laurel A Coons
- Reproductive and Developmental Biology Laboratory, DIR, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, United States
| | - Rene Houtman
- PamGene International B.V., Wolvenhoek 10, NL-5211 HH 's-Hertogenboch, The Netherlands
| | - Rinie van Beuningen
- PamGene International B.V., Wolvenhoek 10, NL-5211 HH 's-Hertogenboch, The Netherlands
| | - Bonnie Goodwin
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD 20850, United States
| | - Scott S Auerbach
- Biomolecular Screening Branch, DNTP, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, United States
| | - Christina T Teng
- Biomolecular Screening Branch, DNTP, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, United States.
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31
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Nakata D, Koyama R, Nakayama K, Kitazawa S, Watanabe T, Hara T. Glycogen synthase kinase-3 inhibitors suppress the AR-V7-mediated transcription and selectively inhibit cell growth in AR-V7-positive prostate cancer cells. Prostate 2017; 77:955-961. [PMID: 28397338 DOI: 10.1002/pros.23351] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 03/14/2017] [Indexed: 11/05/2022]
Abstract
BACKGROUND Recent evidence suggests that androgen receptor (AR) splice variants, including AR-V7, play a pivotal role in resistance to androgen blockade in prostate cancer treatment. The development of new therapeutic agents that can suppress the transcriptional activities of AR splice variants has been anticipated as the next generation treatment of castration-resistant prostate cancer. METHODS High-throughput screening of AR-V7 signaling inhibitors was performed using an AR-V7 reporter system. The effects of a glycogen synthase kinase-3 (GSK3) inhibitor, LY-2090314, on endogenous AR-V7 signaling were evaluated in an AR-V7-positive cell line, JDCaP-hr, by quantitative reverse transcription polymerase chain reaction. The relationship between AR-V7 signaling and β-catenin signaling was assessed using RNA interference. The effect of LY-2090314 on cell growth in various prostate cancer cell lines was also evaluated. RESULTS We identified GSK3 inhibitors as transcriptional suppressors of AR-V7 using a high-throughput screen with an AR-V7 reporter system. LY-2090314 suppressed the reporter activity and endogenous AR-V7 activity in JDCaP-hr cells. Because silencing of β-catenin partly rescued the suppression, it was evident that the suppression was mediated, at least partially, via the activation of β-catenin signaling. AR-V7 signaling and β-catenin signaling reciprocally regulate each other in JDCaP-hr cells, and therefore, GSK3 inhibition can repress AR-V7 transcriptional activity by accumulating intracellular β-catenin. Notably, LY-2090314 selectively inhibited the growth of AR-V7-positive prostate cancer cells in vitro. CONCLUSIONS Our findings demonstrate the potential of GSK3 inhibitors in treating advanced prostate cancer driven by AR splice variants. In vivo evaluation of AR splice variant-positive prostate cancer models will help illustrate the overall significance of GSK3 inhibitors in treating prostate cancer.
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Affiliation(s)
- Daisuke Nakata
- Oncology Drug Discovery Unit, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
| | - Ryokichi Koyama
- Biomolecular Research Laboratories, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
| | - Kazuhide Nakayama
- Oncology Drug Discovery Unit, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
| | - Satoshi Kitazawa
- Oncology Drug Discovery Unit, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
| | - Tatsuya Watanabe
- Oncology Drug Discovery Unit, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
| | - Takahito Hara
- Oncology Drug Discovery Unit, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
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32
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Monaghan AE, McEwan IJ. A sting in the tail: the N-terminal domain of the androgen receptor as a drug target. Asian J Androl 2017; 18:687-94. [PMID: 27212126 PMCID: PMC5000789 DOI: 10.4103/1008-682x.181081] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The role of androgen receptor (AR) in the initiation and progression of prostate cancer (PCa) is well established. Competitive inhibition of the AR ligand-binding domain (LBD) has been the staple of antiandrogen therapies employed to combat the disease in recent years. However, their efficacy has often been limited by the emergence of resistance, mediated through point mutations, and receptor truncations. As a result, the prognosis for patients with malignant castrate resistant disease remains poor. The amino-terminal domain (NTD) of the AR has been shown to be critical for AR function. Its modular activation function (AF-1) is important for both gene regulation and participation in protein-protein interactions. However, due to the intrinsically disordered structure of the domain, its potential as a candidate for therapeutic intervention has been dismissed in the past. The recent emergence of the small molecule EPI-001 has provided evidence that AR-NTD can be targeted therapeutically, independent of the LBD. Targeting of AR-NTD has the potential to disrupt multiple intermolecular interactions between AR and its coregulatory binding partners, in addition to intramolecular cross-talk between the domains of the AR. Therapeutics targeting these protein-protein interactions or NTD directly should also have efficacy against emerging AR splice variants which may play a role in PCa progression. This review will discuss the role of intrinsic disorder in AR function and illustrate how emerging therapies might target NTD in PCa.
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Affiliation(s)
- Amy E Monaghan
- School of Medicine, Medical Sciences and Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, United Kingdom
| | - Iain J McEwan
- School of Medicine, Medical Sciences and Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, United Kingdom
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33
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Russo A, Manna SL, Novellino E, Malfitano AM, Marasco D. Molecular signaling involving intrinsically disordered proteins in prostate cancer. Asian J Androl 2017; 18:673-81. [PMID: 27212129 PMCID: PMC5000787 DOI: 10.4103/1008-682x.181817] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Investigations on cellular protein interaction networks (PINs) reveal that proteins that constitute hubs in a PIN are notably enriched in Intrinsically Disordered Proteins (IDPs) compared to proteins that constitute edges, highlighting the role of IDPs in signaling pathways. Most IDPs rapidly undergo disorder-to-order transitions upon binding to their biological targets to perform their function. Conformational dynamics enables IDPs to be versatile and to interact with a broad range of interactors under normal physiological conditions where their expression is tightly modulated. IDPs are involved in many cellular processes such as cellular signaling, transcriptional regulation, and splicing; thus, their high-specificity/low-affinity interactions play crucial roles in many human diseases including cancer. Prostate cancer (PCa) is one of the leading causes of cancer-related mortality in men worldwide. Therefore, identifying molecular mechanisms of the oncogenic signaling pathways that are involved in prostate carcinogenesis is crucial. In this review, we focus on the aspects of cellular pathways leading to PCa in which IDPs exert a primary role.
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Affiliation(s)
- Anna Russo
- Department of Pharmacy, Centro Interuniversitario di Ricerca sui Peptidi Bioattivi, University of Naples "Federico II", 80134 Naples, Italy
| | - Sara La Manna
- Department of Pharmacy, Centro Interuniversitario di Ricerca sui Peptidi Bioattivi, University of Naples "Federico II", 80134 Naples, Italy
| | - Ettore Novellino
- Department of Pharmacy, Centro Interuniversitario di Ricerca sui Peptidi Bioattivi, University of Naples "Federico II", 80134 Naples, Italy
| | - Anna Maria Malfitano
- Department of Pharmacy, Centro Interuniversitario di Ricerca sui Peptidi Bioattivi, University of Naples "Federico II", 80134 Naples, Italy
| | - Daniela Marasco
- Department of Pharmacy, Centro Interuniversitario di Ricerca sui Peptidi Bioattivi, University of Naples "Federico II", 80134 Naples, Italy
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34
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Phosphorylation-induced conformational dynamics in an intrinsically disordered protein and potential role in phenotypic heterogeneity. Proc Natl Acad Sci U S A 2017; 114:E2644-E2653. [PMID: 28289210 DOI: 10.1073/pnas.1700082114] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Intrinsically disordered proteins (IDPs) that lack a unique 3D structure and comprise a large fraction of the human proteome play important roles in numerous cellular functions. Prostate-Associated Gene 4 (PAGE4) is an IDP that acts as a potentiator of the Activator Protein-1 (AP-1) transcription factor. Homeodomain-Interacting Protein Kinase 1 (HIPK1) phosphorylates PAGE4 at S9 and T51, but only T51 is critical for its activity. Here, we identify a second kinase, CDC-Like Kinase 2 (CLK2), which acts on PAGE4 and hyperphosphorylates it at multiple S/T residues, including S9 and T51. We demonstrate that HIPK1 is expressed in both androgen-dependent and androgen-independent prostate cancer (PCa) cells, whereas CLK2 and PAGE4 are expressed only in androgen-dependent cells. Cell-based studies indicate that PAGE4 interaction with the two kinases leads to opposing functions. HIPK1-phosphorylated PAGE4 (HIPK1-PAGE4) potentiates c-Jun, whereas CLK2-phosphorylated PAGE4 (CLK2-PAGE4) attenuates c-Jun activity. Consistent with the cellular data, biophysical measurements (small-angle X-ray scattering, single-molecule fluorescence resonance energy transfer, and NMR) indicate that HIPK1-PAGE4 exhibits a relatively compact conformational ensemble that binds AP-1, whereas CLK2-PAGE4 is more expanded and resembles a random coil with diminished affinity for AP-1. Taken together, the results suggest that the phosphorylation-induced conformational dynamics of PAGE4 may play a role in modulating changes between PCa cell phenotypes. A mathematical model based on our experimental data demonstrates how differential phosphorylation of PAGE4 can lead to transitions between androgen-dependent and androgen-independent phenotypes by altering the AP-1/androgen receptor regulatory circuit in PCa cells.
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35
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Antonarakis ES, Chandhasin C, Osbourne E, Luo J, Sadar MD, Perabo F. Targeting the N-Terminal Domain of the Androgen Receptor: A New Approach for the Treatment of Advanced Prostate Cancer. Oncologist 2016; 21:1427-1435. [PMID: 27628492 PMCID: PMC5153341 DOI: 10.1634/theoncologist.2016-0161] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2016] [Accepted: 07/08/2016] [Indexed: 12/19/2022] Open
Abstract
: Despite the recent approval and widespread use of abiraterone acetate and enzalutamide for the treatment of castration-resistant prostate cancer (CRPC), this disease still poses significant management challenges because of various tumor escape mechanisms, including those that allow androgen receptor (AR) signaling to remain active. These AR-related resistance mechanisms include AR gene amplification or overexpression, constitutively active ligand-independent AR splice variants, and gain-of-function mutations involving the AR ligand-binding domain (LBD), among others. Therefore, the development of AR-targeted therapies that function independently of the LBD represents an unmet medical need and has the potential to overcome many of these resistance mechanisms. This article discusses N-terminal domain (NTD) inhibition as a novel concept in the field of AR-directed therapies for prostate cancer. AR NTD-targeting agents have the potential to overcome shortcomings of current hormonal therapies by inhibiting all forms of AR-mediated transcriptional activity, and as a result, may affect a broader AR population including mutational and splice variant ARs. Indeed, the first clinical trial of an AR NTD inhibitor is now underway. IMPLICATIONS FOR PRACTICE Because of emerging resistance mechanisms that involve the ligand-binding domain of the androgen receptor (AR), there is currently no effective treatment addressing tumor escape mechanisms related to current AR-targeted therapies. Many patients still demonstrate limited clinical response to current hormonal agents, and castration-resistant prostate cancer remains a lethal disease. Intense research efforts are under way to develop therapies to target resistance mechanisms, including those directed at other parts of the AR molecule. A novel small-molecule agent, EPI-506, represents a new pharmaceutical class, AR N-terminal domain inhibitors, and shows preclinical promise to overcome many known resistance mechanisms related to novel hormonal therapies.
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Affiliation(s)
- Emmanuel S Antonarakis
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, Maryland, USA
- Department of Urology, James Buchanan Brady Urological Institute, Johns Hopkins University, Baltimore, Maryland, USA
| | | | | | - Jun Luo
- Department of Urology, James Buchanan Brady Urological Institute, Johns Hopkins University, Baltimore, Maryland, USA
| | | | - Frank Perabo
- ESSA Pharmaceuticals Corporation, Houston, Texas, USA
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36
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De Mol E, Fenwick RB, Phang CTW, Buzón V, Szulc E, de la Fuente A, Escobedo A, García J, Bertoncini CW, Estébanez-Perpiñá E, McEwan IJ, Riera A, Salvatella X. EPI-001, A Compound Active against Castration-Resistant Prostate Cancer, Targets Transactivation Unit 5 of the Androgen Receptor. ACS Chem Biol 2016; 11:2499-505. [PMID: 27356095 DOI: 10.1021/acschembio.6b00182] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Castration-resistant prostate cancer is the lethal condition suffered by prostate cancer patients that become refractory to androgen deprivation therapy. EPI-001 is a recently identified compound active against this condition that modulates the activity of the androgen receptor, a nuclear receptor that is essential for disease progression. The mechanism by which this compound exerts its inhibitory activity is however not yet fully understood. Here we show, by using high resolution solution nuclear magnetic resonance spectroscopy, that EPI-001 selectively interacts with a partially folded region of the transactivation domain of the androgen receptor, known as transactivation unit 5, that is key for the ability of prostate cells to proliferate in the absence of androgens, a distinctive feature of castration-resistant prostate cancer. Our results can contribute to the development of more potent and less toxic novel androgen receptor antagonists for treating this disease.
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Affiliation(s)
- Eva De Mol
- Institute
for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - R. Bryn Fenwick
- Institute
for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Christopher T. W. Phang
- Institute
for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Victor Buzón
- Departament
de Bioquímica i Biología Molecular, and Institute of
Biomedicine, University of Barcelona (IBUB), Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Elzbieta Szulc
- Institute
for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Alex de la Fuente
- Institute
for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Albert Escobedo
- Institute
for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Jesús García
- Institute
for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Carlos W. Bertoncini
- Institute
for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Eva Estébanez-Perpiñá
- Departament
de Bioquímica i Biología Molecular, and Institute of
Biomedicine, University of Barcelona (IBUB), Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Iain J. McEwan
- Institute
of Medical Sciences, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, IMS Building, Foresterhill, Aberdeen AB25 2ZD, Scotland, United Kingdom
| | - Antoni Riera
- Institute
for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
- Departament
de Química Orgànica, Universitat de Barcelona, Martí
i Franqués 1-11, 08028 Barcelona, Spain
| | - Xavier Salvatella
- Institute
for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
- ICREA, Passeig Lluís Companys 23, 08010 Barcelona, Spain
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37
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Asencio-Hernández J, Kieffer B, Delsuc MA. NMR WaterLOGSY Reveals Weak Binding of Bisphenol A with Amyloid Fibers of a Conserved 11 Residue Peptide from Androgen Receptor. PLoS One 2016; 11:e0161948. [PMID: 27583469 PMCID: PMC5008648 DOI: 10.1371/journal.pone.0161948] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 08/15/2016] [Indexed: 12/02/2022] Open
Abstract
There is growing evidence that bisphenol A (BPA), a molecule largely released in the environment, has detrimental effects on ecosystems and on human health. It acts as an endocrine disruptor targeting steroid hormone receptors, such as the estrogen receptor (ER), estrogen-related receptor (ERR) and androgen receptor (AR). BPA-derived molecules have recently been shown to interact with the AR N-terminal domain (AR-NTD), which is known to be largely intrinsically disordered. This N-terminal domain contains an 11 residue conserved domain that forms amyloid fibers upon oxidative dimerisation through its strictly conserved Cys240 residue. We investigate here the interaction of BPA, and other potential endocrine disruptors, with AR-NTD amyloid fibers using the WaterLOGSY NMR experiment. We observed a selective binding of these compounds to the amyloid fibers formed by the AR-NTD conserved region and glutamine homopolymers. This observation suggests that the high potency of endocrine disruptors may result, in part, from their ability to bind amyloid forms of nuclear receptors in addition to their cognate binding sites. This property may be exploited to design future therapeutic strategies targeting AR related diseases such as the spinal bulbar muscular atrophy or prostate cancer. The ability of NMR WaterLOGSY experiments to detect weak interactions between small ligands and amyloid fibers may prove to be of particular interest for identifying promising hit molecules.
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Affiliation(s)
- Julia Asencio-Hernández
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U596, CNRS UMR 7104, Université de Strasbourg, Illkirch-Graffenstaden, France
| | - Bruno Kieffer
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U596, CNRS UMR 7104, Université de Strasbourg, Illkirch-Graffenstaden, France
| | - Marc-André Delsuc
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U596, CNRS UMR 7104, Université de Strasbourg, Illkirch-Graffenstaden, France
- * E-mail:
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38
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Biron E, Bédard F. Recent progress in the development of protein-protein interaction inhibitors targeting androgen receptor-coactivator binding in prostate cancer. J Steroid Biochem Mol Biol 2016. [PMID: 26196120 DOI: 10.1016/j.jsbmb.2015.07.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The androgen receptor (AR) is a key regulator for the growth, differentiation and survival of prostate cancer cells. Identified as a primary target for the treatment of prostate cancer, many therapeutic strategies have been developed to attenuate AR signaling in prostate cancer cells. While frontline androgen-deprivation therapies targeting either the production or action of androgens usually yield favorable responses in prostate cancer patients, a significant number acquire treatment resistance. Known as the castration-resistant prostate cancer (CRPC), the treatment options are limited for this advanced stage. It has been shown that AR signaling is restored in CRPC due to many aberrant mechanisms such as AR mutations, amplification or expression of constitutively active splice-variants. Coregulator recruitment is a crucial regulatory step in AR signaling and the direct blockade of coactivator binding to AR offers the opportunity to develop therapeutic agents that would remain effective in prostate cancer cells resistant to conventional endocrine therapies. Structural analyses of the AR have identified key surfaces involved in protein-protein interaction with coregulators that have been recently used to design and develop promising AR-coactivator binding inhibitors. In this review we will discuss the design and development of small-molecule inhibitors targeting the AR-coactivator interactions for the treatment of prostate cancer.
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Affiliation(s)
- Eric Biron
- Faculty of Pharmacy and Centre de recherche en endocrinologie moléculaire et oncologique et génomique humaine, Université Laval, Canada; Laboratory of Medicinal Chemistry, CHU de Québec Research Centre, G1 V 4G2, Québec, QC, Canada.
| | - François Bédard
- Faculty of Pharmacy and Centre de recherche en endocrinologie moléculaire et oncologique et génomique humaine, Université Laval, Canada; Laboratory of Medicinal Chemistry, CHU de Québec Research Centre, G1 V 4G2, Québec, QC, Canada
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39
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Imamura Y, Sadar MD. Androgen receptor targeted therapies in castration-resistant prostate cancer: Bench to clinic. Int J Urol 2016; 23:654-65. [PMID: 27302572 PMCID: PMC6680212 DOI: 10.1111/iju.13137] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 05/05/2016] [Indexed: 12/11/2022]
Abstract
The androgen receptor is a transcription factor and validated therapeutic target for prostate cancer. Androgen deprivation therapy remains the gold standard treatment, but it is not curative, and eventually the disease will return as lethal castration‐resistant prostate cancer. There have been improvements in the therapeutic landscape with new agents approved, such as abiraterone acetate, enzalutamide, sipuleucel‐T, cabazitaxel and Ra‐223, in the past 5 years. New insight into the mechanisms of resistance to treatments in advanced disease is being and has been elucidated. All current androgen receptor‐targeting therapies inhibit the growth of prostate cancer by blocking the ligand‐binding domain, where androgen binds to activate the receptor. Persuasive evidence supports the concept that constitutively active androgen receptor splice variants lacking the ligand‐binding domain are one of the resistant mechanisms underlying advanced disease. Transcriptional activity of the androgen receptor requires a functional AF‐1 region in its N‐terminal domain. Preclinical evidence proved that this domain is a druggable target to forecast a potential paradigm shift in the management of advanced prostate cancer. This review presents an overview of androgen receptor‐related mechanisms of resistance as well as novel therapeutic agents to overcome resistance that is linked to the expression of androgen receptor splice variants in castration‐resistant prostate cancer.
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Affiliation(s)
- Yusuke Imamura
- Genome Sciences Center, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Marianne D Sadar
- Genome Sciences Center, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
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40
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Zhi X, Zhou XE, Melcher K, Xu HE. Structures and regulation of non-X orphan nuclear receptors: A retinoid hypothesis. J Steroid Biochem Mol Biol 2016; 157:27-40. [PMID: 26159912 DOI: 10.1016/j.jsbmb.2015.06.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 06/10/2015] [Accepted: 06/16/2015] [Indexed: 12/28/2022]
Abstract
Nuclear receptors are defined as a family of ligand regulated transcription factors [1-6]. While this definition reflects that ligand binding is a key property of nuclear receptors, it is still a heated subject of debate if all the nuclear receptors (48 human members) can bind ligands (ligands referred here to both physiological and synthetic ligands). Recent studies in nuclear receptor structure biology and pharmacology have undoubtedly increased our knowledge of nuclear receptor functions and their regulation. As a result, they point to new avenues for the discovery and development of nuclear receptor regulators, including nuclear receptor ligands. Here we review the recent literature on orphan nuclear receptor structural analysis and ligand identification, particularly on the orphan nuclear receptors that do not heterodimerize with retinoid X receptors, which we term as non-X orphan receptors. We also propose a speculative "retinoid hypothesis" for a subset of non-X orphan nuclear receptors, which we hope to help shed light on orphan nuclear receptor biology and drug discovery. This article is part of a Special Issue entitled 'Orphan Nuclear Receptors'.
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Affiliation(s)
- Xiaoyong Zhi
- Laboratory of Structural Sciences, Van Andel Research Institute, 333 Bostwick Ave., N.E., Grand Rapids, MI 49503, USA; Autophagy Research Center, University of Texas Southwestern Medical Center, 6000Harry Hines Blvd., Dallas, TX 75390, USA.
| | - X Edward Zhou
- Laboratory of Structural Sciences, Van Andel Research Institute, 333 Bostwick Ave., N.E., Grand Rapids, MI 49503, USA
| | - Karsten Melcher
- Laboratory of Structural Sciences, Van Andel Research Institute, 333 Bostwick Ave., N.E., Grand Rapids, MI 49503, USA
| | - H Eric Xu
- Laboratory of Structural Sciences, Van Andel Research Institute, 333 Bostwick Ave., N.E., Grand Rapids, MI 49503, USA; VARI-SIMM Center, Key Laboratory of Receptor Research, Shanghai Institute of MateriaMedica, Chinese Academy of Sciences, Shanghai 201203, China.
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41
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(Intrinsically disordered) splice variants in the proteome: implications for novel drug discovery. Genes Genomics 2016. [DOI: 10.1007/s13258-015-0384-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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42
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Abstract
Specific conformations of signaling proteins can serve as “signals” in signal transduction by being recognized by receptors.
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Affiliation(s)
- Peter Tompa
- VIB Structural Biology Research Center (SBRC)
- Brussels
- Belgium
- Vrije Universiteit Brussel
- Brussels
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43
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Abstract
The human genome codes for 48 members of the nuclear receptor superfamily, half of which have known ligands. Natural ligands for nuclear receptors are generally lipophilic in nature and include steroid hormones, bile acids, fatty acids, thyroid hormones, certain vitamins, and prostaglandins. Nuclear receptors regulate gene expression programs controlling development, differentiation, metabolic homeostasis and reproduction, in both a temporal and a tissue-selective manner. Since the original cloning of the cDNAs for the estrogen and glucocorticoid receptors, large strides have been made in our understanding of the structure and function of this family of transcription factors and their role in pathophysiology.
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Affiliation(s)
- Iain J McEwan
- School of Medicine, Medical Sciences and Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, Scotland, UK.
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44
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Trinucleotide repeats and protein folding and disease: the perspective from studies with the androgen receptor. Future Sci OA 2015; 1:FSO47. [PMID: 28031874 PMCID: PMC5137883 DOI: 10.4155/fso.15.47] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The androgen receptor (AR), a ligand activated transcription factor plays a number of roles in reproduction, homeostasis and pathogenesis of disease. It has two major polymorphic sequences; a polyglutamine and a polyglycine repeat that determine the length of the protein and influence receptor folding, structure and function. Here, we review the role the folding of the AR plays in the pathogenesis of spinal-bulbar muscular atrophy (SBMA), a neuromuscular degenerative disease arising from expansion of the polyglutamine repeat. We discuss current management for SBMA patients and how research on AR structure function may lead to future drug treatments.
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45
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Raina D, Agarwal P, Lee J, Bharti A, McKnight CJ, Sharma P, Kharbanda S, Kufe D. Characterization of the MUC1-C Cytoplasmic Domain as a Cancer Target. PLoS One 2015; 10:e0135156. [PMID: 26267657 PMCID: PMC4534190 DOI: 10.1371/journal.pone.0135156] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 07/17/2015] [Indexed: 01/27/2023] Open
Abstract
Mucin 1 (MUC1) is a heterodimeric protein that is aberrantly expressed in diverse human carcinomas and certain hematologic malignancies. The oncogenic MUC1 transmembrane C-terminal subunit (MUC1-C) functions in part by transducing growth and survival signals from cell surface receptors. However, little is known about the structure of the MUC1-C cytoplasmic domain as a potential drug target. Using methods for structural predictions, our results indicate that a highly conserved CQCRRK sequence, which is adjacent to the cell membrane, forms a small pocket that exposes the two cysteine residues for forming disulfide bonds. By contrast, the remainder of the MUC1-C cytoplasmic domain has no apparent structure, consistent with an intrinsically disordered protein. Our studies thus focused on targeting the MUC1 CQCRRK region. The results show that L- and D-amino acid CQCRRK-containing peptides bind directly to the CQC motif. We further show that the D-amino acid peptide, designated GO-203, blocks homodimerization of the MUC1-C cytoplasmic domain in vitro and in transfected cells. Moreover, GO-203 binds directly to endogenous MUC1-C in breast and lung cancer cells. Colocalization studies further demonstrate that GO-203 predominantly binds to MUC1-C at the cell membrane. These findings support the further development of agents that target the MUC1-C cytoplasmic domain CQC motif and thereby MUC1-C function in cancer cells.
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Affiliation(s)
- Deepak Raina
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, 02215, United States of America
- Genus Oncology, Boston, MA, 02118, United States of America
| | | | - James Lee
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, 02215, United States of America
| | - Ajit Bharti
- Boston University School of Medicine, Department of Medicine, Boston, MA, 02118, United States of America
| | - C. James McKnight
- Boston University School of Medicine, Department of Physiology & Biophysics, Boston, MA, 02118, United States of America
| | | | - Surender Kharbanda
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, 02215, United States of America
- Genus Oncology, Boston, MA, 02118, United States of America
| | - Donald Kufe
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, 02215, United States of America
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46
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Brand LJ, Olson ME, Ravindranathan P, Guo H, Kempema AM, Andrews TE, Chen X, Raj GV, Harki DA, Dehm SM. EPI-001 is a selective peroxisome proliferator-activated receptor-gamma modulator with inhibitory effects on androgen receptor expression and activity in prostate cancer. Oncotarget 2015; 6:3811-24. [PMID: 25669987 PMCID: PMC4414155 DOI: 10.18632/oncotarget.2924] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 12/14/2014] [Indexed: 01/05/2023] Open
Abstract
The androgen receptor (AR) is a driver of prostate cancer (PCa) cell growth and disease progression. Therapies for advanced PCa exploit AR dependence by blocking the production or action of androgens, but these interventions inevitably fail via multiple mechanisms including mutation or deletion of the AR ligand binding domain (LBD). Thus, the development of new inhibitors which act through non-LBD interfaces is an unmet clinical need. EPI-001 is a bisphenol A-derived compound shown to bind covalently and inhibit the AR NH2-terminal domain (NTD). Here, we demonstrate that EPI-001 has general thiol alkylating activity, resulting in multilevel inhibitory effects on AR in PCa cell lines and tissues. At least one secondary mechanism of action associated with AR inhibition was found to be selective modulation of peroxisome proliferator activated receptor-gamma (PPARγ). These multi-level effects of EPI-001 resulted in inhibition of transcriptional activation units (TAUs) 1 and 5 of the AR NTD, and reduced AR expression. EPI-001 inhibited growth of AR-positive and AR-negative PCa cell lines, with the highest sensitivity observed in LNCaP cells. Overall, this study provides new mechanistic insights to the chemical biology of EPI-001, and raises key issues regarding the use of covalent inhibitors of the intrinsically unstructured AR NTD.
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Affiliation(s)
- Lucas J. Brand
- Graduate Program in Microbiology, Immunology, and Cancer Biology, University of Minnesota, Minneapolis, MN, USA
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA
| | - Margaret E. Olson
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN, USA
| | - Preethi Ravindranathan
- Department of Urology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Hong Guo
- Department of Food Science and Nutrition, University of Minnesota, Minneapolis, MN, USA
| | - Aaron M. Kempema
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN, USA
| | - Timothy E. Andrews
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN, USA
| | - Xiaoli Chen
- Department of Food Science and Nutrition, University of Minnesota, Minneapolis, MN, USA
| | - Ganesh V. Raj
- Department of Urology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Daniel A. Harki
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN, USA
| | - Scott M. Dehm
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, USA
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47
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O'Hara L, McInnes K, Simitsidellis I, Morgan S, Atanassova N, Slowikowska-Hilczer J, Kula K, Szarras-Czapnik M, Milne L, Mitchell RT, Smith LB. Autocrine androgen action is essential for Leydig cell maturation and function, and protects against late-onset Leydig cell apoptosis in both mice and men. FASEB J 2014; 29:894-910. [PMID: 25404712 PMCID: PMC4422361 DOI: 10.1096/fj.14-255729] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Leydig cell number and function decline as men age, and low testosterone is associated with all “Western” cardio-metabolic disorders. However, whether perturbed androgen action within the adult Leydig cell lineage predisposes individuals to this late-onset degeneration remains unknown. To address this, we generated a novel mouse model in which androgen receptor (AR) is ablated from ∼75% of adult Leydig stem cell/cell progenitors, from fetal life onward (Leydig cell AR knockout mice), permitting interrogation of the specific roles of autocrine Leydig cell AR signaling through comparison to adjacent AR-retaining Leydig cells, testes from littermate controls, and to human testes, including from patients with complete androgen insensitivity syndrome (CAIS). This revealed that autocrine AR signaling is dispensable for the attainment of final Leydig cell number but is essential for Leydig cell maturation and regulation of steroidogenic enzymes in adulthood. Furthermore, these studies reveal that autocrine AR signaling in Leydig cells protects against late-onset degeneration of the seminiferous epithelium in mice and inhibits Leydig cell apoptosis in both adult mice and patients with CAIS, possibly via opposing aberrant estrogen signaling. We conclude that autocrine androgen action within Leydig cells is essential for the lifelong support of spermatogenesis and the development and lifelong health of Leydig cells.—O’Hara, L., McInnes, K., Simitsidellis, I., Morgan, S., Atanassova, N., Slowikowska-Hilczer, J., Kula, K., Szarras-Czapnik, M., Milne, L., Mitchell, R. T., Smith, L. B. Autocrine androgen action is essential for Leydig cell maturation and function, and protects against late-onset Leydig cell apoptosis in both mice and men.
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Affiliation(s)
- Laura O'Hara
- *MRC Centre for Reproductive Health and BHF Centre for Cardiovascular Science, University of Edinburgh, The Queen's Medical Research Institute, Edinburgh, United Kingdom; Institute of Experimental Morphology and Anthropology with Museum, Bulgarian Academy of Sciences, Sofia, Bulgaria; Department of Andrology and Reproductive Endocrinology, Medical University of Lodz, Lodz, Poland; and Clinic of Endocrinology and Diabetology, Children's Memorial Health Institute, Warsaw, Poland
| | - Kerry McInnes
- *MRC Centre for Reproductive Health and BHF Centre for Cardiovascular Science, University of Edinburgh, The Queen's Medical Research Institute, Edinburgh, United Kingdom; Institute of Experimental Morphology and Anthropology with Museum, Bulgarian Academy of Sciences, Sofia, Bulgaria; Department of Andrology and Reproductive Endocrinology, Medical University of Lodz, Lodz, Poland; and Clinic of Endocrinology and Diabetology, Children's Memorial Health Institute, Warsaw, Poland
| | - Ioannis Simitsidellis
- *MRC Centre for Reproductive Health and BHF Centre for Cardiovascular Science, University of Edinburgh, The Queen's Medical Research Institute, Edinburgh, United Kingdom; Institute of Experimental Morphology and Anthropology with Museum, Bulgarian Academy of Sciences, Sofia, Bulgaria; Department of Andrology and Reproductive Endocrinology, Medical University of Lodz, Lodz, Poland; and Clinic of Endocrinology and Diabetology, Children's Memorial Health Institute, Warsaw, Poland
| | - Stephanie Morgan
- *MRC Centre for Reproductive Health and BHF Centre for Cardiovascular Science, University of Edinburgh, The Queen's Medical Research Institute, Edinburgh, United Kingdom; Institute of Experimental Morphology and Anthropology with Museum, Bulgarian Academy of Sciences, Sofia, Bulgaria; Department of Andrology and Reproductive Endocrinology, Medical University of Lodz, Lodz, Poland; and Clinic of Endocrinology and Diabetology, Children's Memorial Health Institute, Warsaw, Poland
| | - Nina Atanassova
- *MRC Centre for Reproductive Health and BHF Centre for Cardiovascular Science, University of Edinburgh, The Queen's Medical Research Institute, Edinburgh, United Kingdom; Institute of Experimental Morphology and Anthropology with Museum, Bulgarian Academy of Sciences, Sofia, Bulgaria; Department of Andrology and Reproductive Endocrinology, Medical University of Lodz, Lodz, Poland; and Clinic of Endocrinology and Diabetology, Children's Memorial Health Institute, Warsaw, Poland
| | - Jolanta Slowikowska-Hilczer
- *MRC Centre for Reproductive Health and BHF Centre for Cardiovascular Science, University of Edinburgh, The Queen's Medical Research Institute, Edinburgh, United Kingdom; Institute of Experimental Morphology and Anthropology with Museum, Bulgarian Academy of Sciences, Sofia, Bulgaria; Department of Andrology and Reproductive Endocrinology, Medical University of Lodz, Lodz, Poland; and Clinic of Endocrinology and Diabetology, Children's Memorial Health Institute, Warsaw, Poland
| | - Krzysztof Kula
- *MRC Centre for Reproductive Health and BHF Centre for Cardiovascular Science, University of Edinburgh, The Queen's Medical Research Institute, Edinburgh, United Kingdom; Institute of Experimental Morphology and Anthropology with Museum, Bulgarian Academy of Sciences, Sofia, Bulgaria; Department of Andrology and Reproductive Endocrinology, Medical University of Lodz, Lodz, Poland; and Clinic of Endocrinology and Diabetology, Children's Memorial Health Institute, Warsaw, Poland
| | - Maria Szarras-Czapnik
- *MRC Centre for Reproductive Health and BHF Centre for Cardiovascular Science, University of Edinburgh, The Queen's Medical Research Institute, Edinburgh, United Kingdom; Institute of Experimental Morphology and Anthropology with Museum, Bulgarian Academy of Sciences, Sofia, Bulgaria; Department of Andrology and Reproductive Endocrinology, Medical University of Lodz, Lodz, Poland; and Clinic of Endocrinology and Diabetology, Children's Memorial Health Institute, Warsaw, Poland
| | - Laura Milne
- *MRC Centre for Reproductive Health and BHF Centre for Cardiovascular Science, University of Edinburgh, The Queen's Medical Research Institute, Edinburgh, United Kingdom; Institute of Experimental Morphology and Anthropology with Museum, Bulgarian Academy of Sciences, Sofia, Bulgaria; Department of Andrology and Reproductive Endocrinology, Medical University of Lodz, Lodz, Poland; and Clinic of Endocrinology and Diabetology, Children's Memorial Health Institute, Warsaw, Poland
| | - Rod T Mitchell
- *MRC Centre for Reproductive Health and BHF Centre for Cardiovascular Science, University of Edinburgh, The Queen's Medical Research Institute, Edinburgh, United Kingdom; Institute of Experimental Morphology and Anthropology with Museum, Bulgarian Academy of Sciences, Sofia, Bulgaria; Department of Andrology and Reproductive Endocrinology, Medical University of Lodz, Lodz, Poland; and Clinic of Endocrinology and Diabetology, Children's Memorial Health Institute, Warsaw, Poland
| | - Lee B Smith
- *MRC Centre for Reproductive Health and BHF Centre for Cardiovascular Science, University of Edinburgh, The Queen's Medical Research Institute, Edinburgh, United Kingdom; Institute of Experimental Morphology and Anthropology with Museum, Bulgarian Academy of Sciences, Sofia, Bulgaria; Department of Andrology and Reproductive Endocrinology, Medical University of Lodz, Lodz, Poland; and Clinic of Endocrinology and Diabetology, Children's Memorial Health Institute, Warsaw, Poland
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48
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Banuelos CA, Lal A, Tien AH, Shah N, Yang YC, Mawji NR, Meimetis LG, Park J, Kunzhong J, Andersen RJ, Sadar MD. Characterization of niphatenones that inhibit androgen receptor N-terminal domain. PLoS One 2014; 9:e107991. [PMID: 25268119 PMCID: PMC4182434 DOI: 10.1371/journal.pone.0107991] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 08/18/2014] [Indexed: 01/24/2023] Open
Abstract
Androgen ablation therapy causes a temporary reduction in tumor burden in patients with advanced prostate cancer. Unfortunately the malignancy will return to form lethal castration-recurrent prostate cancer (CRPC). The androgen receptor (AR) remains transcriptionally active in CRPC in spite of castrate levels of androgens in the blood. AR transcriptional activity resides in its N-terminal domain (NTD). Possible mechanisms of continued AR transcriptional activity may include, at least in part, expression of constitutively active splice variants of AR that lack the C-terminal ligand-binding domain (LBD). Current therapies that target the AR LBD, would not be effective against these AR variants. Currently no drugs are clinically available that target the AR NTD which should be effective against these AR variants as well as full-length AR. Niphatenones were originally isolated and identified in active extracts from Niphates digitalis marine sponge. Here we begin to characterize the mechanism of niphatenones in blocking AR transcriptional activity. Both enantiomers had similar IC50 values of 6 µM for inhibiting the full-length AR in a functional transcriptional assay. However, (S)-niphatenone had significantly better activity against the AR NTD compared to (R)-niphatenone. Consistent with niphatenones binding to and inhibiting transactivation of AR NTD, niphatenones inhibited AR splice variant. Niphatenone did not affect the transcriptional activity of the related progesterone receptor, but slightly decreased glucocorticoid receptor (GR) activity and covalently bound to GR activation function-1 (AF-1) region. Niphatenone blocked N/C interactions of AR without altering either AR protein levels or its intracellular localization in response to androgen. Alkylation with glutathione suggests that niphatenones are not a feasible scaffold for further drug development.
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Affiliation(s)
- Carmen A. Banuelos
- Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Aaron Lal
- Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Amy H. Tien
- Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Neel Shah
- Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Yu Chi Yang
- Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Nasrin R. Mawji
- Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Labros G. Meimetis
- Chemistry and Earth, Ocean & Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jacob Park
- Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Jian Kunzhong
- Chemistry and Earth, Ocean & Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Raymond J. Andersen
- Chemistry and Earth, Ocean & Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Marianne D. Sadar
- Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
- * E-mail:
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49
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Uversky VN. Wrecked regulation of intrinsically disordered proteins in diseases: pathogenicity of deregulated regulators. Front Mol Biosci 2014; 1:6. [PMID: 25988147 PMCID: PMC4428494 DOI: 10.3389/fmolb.2014.00006] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 07/06/2014] [Indexed: 12/14/2022] Open
Abstract
Biologically active proteins without stable tertiary structure are common in all known proteomes. Functions of these intrinsically disordered proteins (IDPs) are typically related to regulation, signaling, and control. Cellular levels of these important regulators are tightly regulated by a variety mechanisms ranging from firmly controlled expression to precisely targeted degradation. Functions of IDPs are controlled by binding to specific partners, alternative splicing, and posttranslational modifications among other means. In the norm, right amounts of precisely activated IDPs have to be present in right time at right places. Wrecked regulation brings havoc to the ordered world of disordered proteins, leading to protein misfolding, misidentification, and missignaling that give rise to numerous human diseases, such as cancer, cardiovascular disease, neurodegenerative diseases, and diabetes. Among factors inducing pathogenic transformations of IDPs are various cellular mechanisms, such as chromosomal translocations, damaged splicing, altered expression, frustrated posttranslational modifications, aberrant proteolytic degradation, and defective trafficking. This review presents some of the aspects of deregulated regulation of IDPs leading to human diseases.
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Affiliation(s)
- Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida Tampa, FL, USA ; Biology Department, Faculty of Science, King Abdulaziz University Jeddah, Saudi Arabia ; Laboratory of New Methods in Biology, Institute for Biological Instrumentation, Russian Academy of Sciences Moscow, Russia
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50
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Uversky VN, Davé V, Iakoucheva LM, Malaney P, Metallo SJ, Pathak RR, Joerger AC. Pathological unfoldomics of uncontrolled chaos: intrinsically disordered proteins and human diseases. Chem Rev 2014; 114:6844-79. [PMID: 24830552 PMCID: PMC4100540 DOI: 10.1021/cr400713r] [Citation(s) in RCA: 196] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Vladimir N. Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer’s Research Institute University of South Florida, Tampa, Florida 33612, United States
- Institute for Biological Instrumentation, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 22254, Saudi Arabia
| | - Vrushank Davé
- Department of Pathology and Cell Biology , Morsani College of Medicine, University of South Florida, Tampa, Florida 33612, United States
- Department of Molecular Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida 33612, United States
| | - Lilia M. Iakoucheva
- Department of Psychiatry, University of California San Diego, La Jolla, California 92093, United States
| | - Prerna Malaney
- Department of Pathology and Cell Biology , Morsani College of Medicine, University of South Florida, Tampa, Florida 33612, United States
| | - Steven J. Metallo
- Department of Chemistry, Georgetown University, Washington, District of Columbia 20057, United States
| | - Ravi Ramesh Pathak
- Department of Pathology and Cell Biology , Morsani College of Medicine, University of South Florida, Tampa, Florida 33612, United States
| | - Andreas C. Joerger
- Medical Research Council Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, United Kingdom
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