1
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Bedir M, Outwin E, Colnaghi R, Bassett L, Abramowicz I, O'Driscoll M. A novel role for the peptidyl-prolyl cis-trans isomerase Cyclophilin A in DNA-repair following replication fork stalling via the MRE11-RAD50-NBS1 complex. EMBO Rep 2024; 25:3432-3455. [PMID: 38943005 PMCID: PMC11315929 DOI: 10.1038/s44319-024-00184-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 05/28/2024] [Accepted: 06/05/2024] [Indexed: 06/30/2024] Open
Abstract
Cyclosporin A (CsA) induces DNA double-strand breaks in LIG4 syndrome fibroblasts, specifically upon transit through S-phase. The basis underlying this has not been described. CsA-induced genomic instability may reflect a direct role of Cyclophilin A (CYPA) in DNA repair. CYPA is a peptidyl-prolyl cis-trans isomerase (PPI). CsA inhibits the PPI activity of CYPA. Using an integrated approach involving CRISPR/Cas9-engineering, siRNA, BioID, co-immunoprecipitation, pathway-specific DNA repair investigations as well as protein expression interaction analysis, we describe novel impacts of CYPA loss and inhibition on DNA repair. We characterise a direct CYPA interaction with the NBS1 component of the MRE11-RAD50-NBS1 complex, providing evidence that CYPA influences DNA repair at the level of DNA end resection. We define a set of genetic vulnerabilities associated with CYPA loss and inhibition, identifying DNA replication fork protection as an important determinant of viability. We explore examples of how CYPA inhibition may be exploited to selectively kill cancers sharing characteristic genomic instability profiles, including MYCN-driven Neuroblastoma, Multiple Myeloma and Chronic Myelogenous Leukaemia. These findings propose a repurposing strategy for Cyclophilin inhibitors.
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Affiliation(s)
- Marisa Bedir
- Human DNA Damage Response Disorders Group, Genome Damage & Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK
| | - Emily Outwin
- Human DNA Damage Response Disorders Group, Genome Damage & Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK
| | - Rita Colnaghi
- Human DNA Damage Response Disorders Group, Genome Damage & Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK
| | - Lydia Bassett
- Human DNA Damage Response Disorders Group, Genome Damage & Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK
| | - Iga Abramowicz
- Human DNA Damage Response Disorders Group, Genome Damage & Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK
| | - Mark O'Driscoll
- Human DNA Damage Response Disorders Group, Genome Damage & Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK.
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2
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Lu KP, Zhou XZ. Pin1-catalyzed conformational regulation after phosphorylation: A distinct checkpoint in cell signaling and drug discovery. Sci Signal 2024; 17:eadi8743. [PMID: 38889227 DOI: 10.1126/scisignal.adi8743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 05/30/2024] [Indexed: 06/20/2024]
Abstract
Protein phosphorylation is one of the most common mechanisms regulating cellular signaling pathways, and many kinases and phosphatases are proven drug targets. Upon phosphorylation, protein functions can be further regulated by the distinct isomerase Pin1 through cis-trans isomerization. Numerous protein targets and many important roles have now been elucidated for Pin1. However, no tools are available to detect or target cis and trans conformation events in cells. The development of Pin1 inhibitors and stereo- and phospho-specific antibodies has revealed that cis and trans conformations have distinct and often opposing cellular functions. Aberrant conformational changes due to the dysregulation of Pin1 can drive pathogenesis but can be effectively targeted in age-related diseases, including cancers and neurodegenerative disorders. Here, we review advances in understanding the roles of Pin1 signaling in health and disease and highlight conformational regulation as a distinct signal transduction checkpoint in disease development and treatment.
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Affiliation(s)
- Kun Ping Lu
- Departments of Biochemistry and Oncology, Schulich School of Medicine & Dentistry, Western University, London, ON N6G 2V4, Canada
- Robarts Research Institute, Schulich School of Medicine & Dentistry, Western University, London, ON N6G 2V4, Canada
| | - Xiao Zhen Zhou
- Departments of Biochemistry and Oncology, Schulich School of Medicine & Dentistry, Western University, London, ON N6G 2V4, Canada
- Department of Pathology and Laboratory Medicine, Schulich School of Medicine & Dentistry, Western University, London, ON N6G 2V4, Canada
- Lawson Health Research Institute, Schulich School of Medicine & Dentistry, Western University, London, ON N6G 2V4, Canada
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3
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Jeong J, Usman M, Li Y, Zhou XZ, Lu KP. Pin1-Catalyzed Conformation Changes Regulate Protein Ubiquitination and Degradation. Cells 2024; 13:731. [PMID: 38727267 PMCID: PMC11083468 DOI: 10.3390/cells13090731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 04/12/2024] [Accepted: 04/14/2024] [Indexed: 05/13/2024] Open
Abstract
The unique prolyl isomerase Pin1 binds to and catalyzes cis-trans conformational changes of specific Ser/Thr-Pro motifs after phosphorylation, thereby playing a pivotal role in regulating the structure and function of its protein substrates. In particular, Pin1 activity regulates the affinity of a substrate for E3 ubiquitin ligases, thereby modulating the turnover of a subset of proteins and coordinating their activities after phosphorylation in both physiological and disease states. In this review, we highlight recent advancements in Pin1-regulated ubiquitination in the context of cancer and neurodegenerative disease. Specifically, Pin1 promotes cancer progression by increasing the stabilities of numerous oncoproteins and decreasing the stabilities of many tumor suppressors. Meanwhile, Pin1 plays a critical role in different neurodegenerative disorders via the regulation of protein turnover. Finally, we propose a novel therapeutic approach wherein the ubiquitin-proteasome system can be leveraged for therapy by targeting pathogenic intracellular targets for TRIM21-dependent degradation using stereospecific antibodies.
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Affiliation(s)
- Jessica Jeong
- Departments of Biochemistry and Oncology, Schulich School of Medicine & Dentistry, Western University, London, ON N6A 5C1, Canada; (J.J.)
- Robarts Research Institute, Western University, London, ON N6A 5B7, Canada
| | - Muhammad Usman
- Departments of Biochemistry and Oncology, Schulich School of Medicine & Dentistry, Western University, London, ON N6A 5C1, Canada; (J.J.)
- Robarts Research Institute, Western University, London, ON N6A 5B7, Canada
| | - Yitong Li
- Departments of Biochemistry and Oncology, Schulich School of Medicine & Dentistry, Western University, London, ON N6A 5C1, Canada; (J.J.)
- Robarts Research Institute, Western University, London, ON N6A 5B7, Canada
| | - Xiao Zhen Zhou
- Departments of Biochemistry and Oncology, Schulich School of Medicine & Dentistry, Western University, London, ON N6A 5C1, Canada; (J.J.)
- Department of Pathology and Laboratory Medicine, and Oncology, Schulich School of Medicine & Dentistry, Western University, London, ON N6A 5C1, Canada
- Lawson Health Research Institute, Western University, London, ON N6C 2R5, Canada
| | - Kun Ping Lu
- Departments of Biochemistry and Oncology, Schulich School of Medicine & Dentistry, Western University, London, ON N6A 5C1, Canada; (J.J.)
- Robarts Research Institute, Western University, London, ON N6A 5B7, Canada
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4
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Stallings NR, O'Neal MA, Hu J, Shen ZJ, Malter JS. Long-term normalization of calcineurin activity in model mice rescues Pin1 and attenuates Alzheimer's phenotypes without blocking peripheral T cell IL-2 response. Alzheimers Res Ther 2023; 15:179. [PMID: 37849016 PMCID: PMC10580561 DOI: 10.1186/s13195-023-01323-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 10/03/2023] [Indexed: 10/19/2023]
Abstract
BACKGROUND Current treatments for Alzheimer's disease (AD) have largely failed to yield significant therapeutic benefits. Novel approaches are desperately needed to help address this immense public health issue. Data suggests that early intervention at the first stages of mild cognitive impairment may have a greater chance for success. The calcineurin (CN)-Pin1 signaling cascade can be selectively targeted with tacrolimus (FK506), a highly specific, FDA-approved CN inhibitor used safely for > 20 years in solid organ transplant recipients. AD prevalence was significantly reduced in solid organ recipients treated with FK506. METHODS Time release pellets were used to deliver constant FK506 dosage to APP/PS1 mice without deleterious manipulation or handling. Immunofluorescence, histology, molecular biology, and behavior were used to evaluate changes in AD pathology. RESULTS FK506 can be safely and consistently delivered into juvenile APP/PS1 mice via time-release pellets to levels roughly seen in transplant patients, leading to the normalization of CN activity and reduction or elimination of AD pathologies including synapse loss, neuroinflammation, and cognitive impairment. Pin1 activity and function were rescued despite the continuing presence of high levels of transgenic Aβ42. Indicators of neuroinflammation including Iba1 positivity and IL-6 production were also reduced to normal levels. Peripheral blood mononuclear cells (PBMC) obtained during treatment or splenocytes isolated at euthanasia activated normally after mitogens. CONCLUSIONS Low-dose, constant FK506 can normalize CNS CN and Pin1 activity, suppress neuroinflammation, and attenuate AD-associated pathology without blocking peripheral IL-2 responses making repurposed FK506 a viable option for early, therapeutic intervention in AD.
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Affiliation(s)
- Nancy R Stallings
- Department of Pathology, University of Texas Southwestern Medical Center, 5323 Harry Hines, Dallas, TX, 75390, USA
| | - Melissa A O'Neal
- Department of Pathology, University of Texas Southwestern Medical Center, 5323 Harry Hines, Dallas, TX, 75390, USA
| | - Jie Hu
- Department of Pathology, University of Texas Southwestern Medical Center, 5323 Harry Hines, Dallas, TX, 75390, USA
| | - Zhong-Jian Shen
- Department of Pathology, University of Texas Southwestern Medical Center, 5323 Harry Hines, Dallas, TX, 75390, USA
| | - James S Malter
- Department of Pathology, University of Texas Southwestern Medical Center, 5323 Harry Hines, Dallas, TX, 75390, USA.
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5
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Li F, Mladenov E, Sun Y, Soni A, Stuschke M, Timmermann B, Iliakis G. Low CDK Activity and Enhanced Degradation by APC/C CDH1 Abolishes CtIP Activity and Alt-EJ in Quiescent Cells. Cells 2023; 12:1530. [PMID: 37296650 PMCID: PMC10252496 DOI: 10.3390/cells12111530] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 05/26/2023] [Accepted: 05/27/2023] [Indexed: 06/12/2023] Open
Abstract
Alt-EJ is an error-prone DNA double-strand break (DSBs) repair pathway coming to the fore when first-line repair pathways, c-NHEJ and HR, are defective or fail. It is thought to benefit from DNA end-resection-a process whereby 3' single-stranded DNA-tails are generated-initiated by the CtIP/MRE11-RAD50-NBS1 (MRN) complex and extended by EXO1 or the BLM/DNA2 complex. The connection between alt-EJ and resection remains incompletely characterized. Alt-EJ depends on the cell cycle phase, is at maximum in G2-phase, substantially reduced in G1-phase and almost undetectable in quiescent, G0-phase cells. The mechanism underpinning this regulation remains uncharacterized. Here, we compare alt-EJ in G1- and G0-phase cells exposed to ionizing radiation (IR) and identify CtIP-dependent resection as the key regulator. Low levels of CtIP in G1-phase cells allow modest resection and alt-EJ, as compared to G2-phase cells. Strikingly, CtIP is undetectable in G0-phase cells owing to APC/C-mediated degradation. The suppression of CtIP degradation with bortezomib or CDH1-depletion rescues CtIP and alt-EJ in G0-phase cells. CtIP activation in G0-phase cells also requires CDK-dependent phosphorylation by any available CDK but is restricted to CDK4/6 at the early stages of the normal cell cycle. We suggest that suppression of mutagenic alt-EJ in G0-phase is a mechanism by which cells of higher eukaryotes maintain genomic stability in a large fraction of non-cycling cells in their organisms.
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Affiliation(s)
- Fanghua Li
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (F.L.); (E.M.); (Y.S.); (A.S.)
- Department of Particle Therapy, University Hospital Essen, West German Proton Therapy Centre Essen (WPE), West German Cancer Center (WTZ), German Cancer Consortium (DKTK), 45147 Essen, Germany;
| | - Emil Mladenov
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (F.L.); (E.M.); (Y.S.); (A.S.)
- Division of Experimental Radiation Biology, Department of Radiation Therapy, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany;
| | - Yanjie Sun
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (F.L.); (E.M.); (Y.S.); (A.S.)
- Department of Particle Therapy, University Hospital Essen, West German Proton Therapy Centre Essen (WPE), West German Cancer Center (WTZ), German Cancer Consortium (DKTK), 45147 Essen, Germany;
| | - Aashish Soni
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (F.L.); (E.M.); (Y.S.); (A.S.)
- Division of Experimental Radiation Biology, Department of Radiation Therapy, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany;
| | - Martin Stuschke
- Division of Experimental Radiation Biology, Department of Radiation Therapy, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany;
- German Cancer Consortium (DKTK), Partner Site University Hospital Essen, German Cancer Research Center (DKFZ), 45147 Essen, Germany
| | - Beate Timmermann
- Department of Particle Therapy, University Hospital Essen, West German Proton Therapy Centre Essen (WPE), West German Cancer Center (WTZ), German Cancer Consortium (DKTK), 45147 Essen, Germany;
- German Cancer Consortium (DKTK), Partner Site University Hospital Essen, German Cancer Research Center (DKFZ), 45147 Essen, Germany
| | - George Iliakis
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (F.L.); (E.M.); (Y.S.); (A.S.)
- Division of Experimental Radiation Biology, Department of Radiation Therapy, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany;
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Qiu Z, Hao S, Song S, Zhang R, Yan T, Lu Z, Wang H, Jia Z, Zheng J. PLK1-mediated phosphorylation of PPIL2 regulates HR via CtIP. Front Cell Dev Biol 2022; 10:902403. [PMID: 36092721 PMCID: PMC9452783 DOI: 10.3389/fcell.2022.902403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 08/04/2022] [Indexed: 11/13/2022] Open
Abstract
Homologous recombination (HR) is an error-free DNA double-strand break (DSB) repair pathway, which safeguards genome integrity and cell viability. Human C-terminal binding protein (CtBP)—interacting protein (CtIP) is a central regulator of the pathway which initiates the DNA end resection in HR. Ubiquitination modification of CtIP is known in some cases to control DNA resection and promote HR. However, it remains unclear how cells restrain CtIP activity in unstressed cells. We show that the ubiquitin E3 ligase PPIL2 is recruited to DNA damage sites through interactions with an HR-related protein ZNF830, implying PPIL2’s involvement in DNA repair. We found that PPIL2 interacts with and ubiquitinates CtIP at the K426 site, representing a hereunto unknown ubiquitination site. Ubiquitination of CtIP by PPIL2 suppresses HR and DNA resection. This inhibition of PPIL2 is also modulated by phosphorylation at multiple sites by PLK1, which reduces PPIL2 ubiquitination of CtIP. Our findings reveal new regulatory complexity in CtIP ubiquitination in DSB repair. We propose that the PPIL2-dependent CtIP ubiquitination prevents CtIP from interacting with DNA, thereby inhibiting HR.
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Affiliation(s)
- Zhiyu Qiu
- College of Chemistry, Beijing Normal University, Beijing, China
| | - Shuailin Hao
- Beijing Key Laboratory of DNA Damage Response and College of Life Sciences, Capital Normal University, Beijing, China
| | - Shikai Song
- College of Chemistry, Beijing Normal University, Beijing, China
| | - Ruiling Zhang
- College of Chemistry, Beijing Normal University, Beijing, China
| | - Tingyu Yan
- College of Chemistry, Beijing Normal University, Beijing, China
| | - Zhifang Lu
- College of Chemistry, Beijing Normal University, Beijing, China
| | - Hailong Wang
- Beijing Key Laboratory of DNA Damage Response and College of Life Sciences, Capital Normal University, Beijing, China
| | - Zongchao Jia
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, ON, Canada
- *Correspondence: Zongchao Jia, ; Jimin Zheng,
| | - Jimin Zheng
- College of Chemistry, Beijing Normal University, Beijing, China
- *Correspondence: Zongchao Jia, ; Jimin Zheng,
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7
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ATM controls the extent of DNA end resection by eliciting sequential posttranslational modifications of CtIP. Proc Natl Acad Sci U S A 2021; 118:2022600118. [PMID: 33723063 DOI: 10.1073/pnas.2022600118] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
DNA end resection is a critical step in the repair of DNA double-strand breaks (DSBs) via homologous recombination (HR). However, the mechanisms governing the extent of resection at DSB sites undergoing homology-directed repair remain unclear. Here, we show that, upon DSB induction, the key resection factor CtIP is modified by the ubiquitin-like protein SUMO at lysine 578 in a PIAS4-dependent manner. CtIP SUMOylation occurs on damaged chromatin and requires prior hyperphosphorylation by the ATM protein kinase. SUMO-modified hyperphosphorylated CtIP is targeted by the SUMO-dependent E3 ubiquitin ligase RNF4 for polyubiquitination and subsequent degradation. Consequently, disruption of CtIP SUMOylation results in aberrant accumulation of CtIP at DSBs, which, in turn, causes uncontrolled excessive resection, defective HR, and increased cellular sensitivity to DSB-inducing agents. These findings reveal a previously unidentified regulatory mechanism that regulates CtIP activity at DSBs and thus the extent of end resection via ATM-dependent sequential posttranslational modification of CtIP.
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8
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Targeting Pin1 for Modulation of Cell Motility and Cancer Therapy. Biomedicines 2021; 9:biomedicines9040359. [PMID: 33807199 PMCID: PMC8065645 DOI: 10.3390/biomedicines9040359] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 03/25/2021] [Accepted: 03/27/2021] [Indexed: 01/09/2023] Open
Abstract
Peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 (Pin1) specifically binds and isomerizes the phosphorylated serine/threonine-proline (pSer/Thr-Pro) motif, which leads to changes in protein conformation and function. Pin1 is widely overexpressed in cancers and plays an important role in tumorigenesis. Mounting evidence has revealed that targeting Pin1 is a potential therapeutic approach for various cancers by inhibiting cell proliferation, reducing metastasis, and maintaining genome stability. In this review, we summarize the underlying mechanisms of Pin1-mediated upregulation of oncogenes and downregulation of tumor suppressors in cancer development. Furthermore, we also discuss the multiple roles of Pin1 in cancer hallmarks and examine Pin1 as a desirable pharmaceutical target for cancer therapy. We also summarize the recent progress of Pin1-targeted small-molecule compounds for anticancer activity.
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9
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Namitz KEW, Zheng T, Canning AJ, Alicea-Velazquez NL, Castañeda CA, Cosgrove MS, Hanes SD. Structure analysis suggests Ess1 isomerizes the carboxy-terminal domain of RNA polymerase II via a bivalent anchoring mechanism. Commun Biol 2021; 4:398. [PMID: 33767358 PMCID: PMC7994582 DOI: 10.1038/s42003-021-01906-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 02/24/2021] [Indexed: 01/07/2023] Open
Abstract
Accurate gene transcription in eukaryotes depends on isomerization of serine-proline bonds within the carboxy-terminal domain (CTD) of RNA polymerase II. Isomerization is part of the "CTD code" that regulates recruitment of proteins required for transcription and co-transcriptional RNA processing. Saccharomyces cerevisiae Ess1 and its human ortholog, Pin1, are prolyl isomerases that engage the long heptad repeat (YSPTSPS)26 of the CTD by an unknown mechanism. Here, we used an integrative structural approach to decipher Ess1 interactions with the CTD. Ess1 has a rigid linker between its WW and catalytic domains that enforces a distance constraint for bivalent interaction with the ends of long CTD substrates (≥4-5 heptad repeats). Our binding results suggest that the Ess1 WW domain anchors the proximal end of the CTD substrate during isomerization, and that linker divergence may underlie evolution of substrate specificity.
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Affiliation(s)
- Kevin E. W. Namitz
- grid.411023.50000 0000 9159 4457Department of Biochemistry and Molecular Biology, SUNY-Upstate Medical University, Syracuse, NY USA ,grid.29857.310000 0001 2097 4281Present Address: Department of Chemistry, Pennsylvania State University, University Park, PA USA
| | - Tongyin Zheng
- grid.264484.80000 0001 2189 1568Departments of Biology and Chemistry, Syracuse University, Syracuse, NY USA
| | - Ashley J. Canning
- grid.411023.50000 0000 9159 4457Department of Biochemistry and Molecular Biology, SUNY-Upstate Medical University, Syracuse, NY USA
| | - Nilda L. Alicea-Velazquez
- grid.411023.50000 0000 9159 4457Department of Biochemistry and Molecular Biology, SUNY-Upstate Medical University, Syracuse, NY USA ,grid.247980.00000 0001 2184 3689Present Address: Department of Chemistry and Biochemistry, Central Connecticut State University, New Britain, CT USA
| | - Carlos A. Castañeda
- grid.264484.80000 0001 2189 1568Departments of Biology and Chemistry, Syracuse University, Syracuse, NY USA
| | - Michael S. Cosgrove
- grid.411023.50000 0000 9159 4457Department of Biochemistry and Molecular Biology, SUNY-Upstate Medical University, Syracuse, NY USA
| | - Steven D. Hanes
- grid.411023.50000 0000 9159 4457Department of Biochemistry and Molecular Biology, SUNY-Upstate Medical University, Syracuse, NY USA
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10
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Kuster A, Mozaffari NL, Wilkinson OJ, Wojtaszek JL, Zurfluh C, Przetocka S, Zyla D, von Aesch C, Dillingham MS, Williams RS, Sartori AA. A stapled peptide mimetic of the CtIP tetramerization motif interferes with double-strand break repair and replication fork protection. SCIENCE ADVANCES 2021; 7:7/8/eabc6381. [PMID: 33608267 PMCID: PMC7895427 DOI: 10.1126/sciadv.abc6381] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 01/07/2021] [Indexed: 06/12/2023]
Abstract
Cancer cells display high levels of DNA damage and replication stress, vulnerabilities that could be exploited by drugs targeting DNA repair proteins. Human CtIP promotes homology-mediated repair of DNA double-strand breaks (DSBs) and protects stalled replication forks from nucleolytic degradation, thus representing an attractive candidate for targeted cancer therapy. Here, we establish a peptide mimetic of the CtIP tetramerization motif that inhibits CtIP activity. The hydrocarbon-stapled peptide encompassing amino acid residues 18 to 28 of CtIP (SP18-28) stably binds to CtIP tetramers in vitro and facilitates their aggregation into higher-order structures. Efficient intracellular uptake of SP18-28 abrogates CtIP localization to damaged chromatin, impairs DSB repair, and triggers extensive fork degradation. Moreover, prolonged SP18-28 treatment causes hypersensitivity to DNA-damaging agents and selectively reduces the viability of BRCA1-mutated cancer cell lines. Together, our data provide a basis for the future development of CtIP-targeting compounds with the potential to treat patients with cancer.
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Affiliation(s)
- Anika Kuster
- Institute of Molecular Cancer Research, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - Nour L Mozaffari
- Institute of Molecular Cancer Research, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - Oliver J Wilkinson
- School of Biochemistry, University of Bristol, University Walk, Clifton BS8 1TD, Bristol, UK
| | - Jessica L Wojtaszek
- Structural Cell Biology Group, Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, U.S. National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC 27709, USA
| | - Christina Zurfluh
- Institute of Molecular Cancer Research, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - Sara Przetocka
- Institute of Molecular Cancer Research, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - Dawid Zyla
- Institute of Molecular Biology and Biophysics, ETH-Zürich, Otto-Stern-Weg 5, CH-8093 Zürich, Switzerland
| | - Christine von Aesch
- Institute of Molecular Cancer Research, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - Mark S Dillingham
- School of Biochemistry, University of Bristol, University Walk, Clifton BS8 1TD, Bristol, UK
| | - R Scott Williams
- Structural Cell Biology Group, Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, U.S. National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC 27709, USA
| | - Alessandro A Sartori
- Institute of Molecular Cancer Research, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland.
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11
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Li J, Mo C, Guo Y, Zhang B, Feng X, Si Q, Wu X, Zhao Z, Gong L, He D, Shao J. Roles of peptidyl-prolyl isomerase Pin1 in disease pathogenesis. Theranostics 2021; 11:3348-3358. [PMID: 33537091 PMCID: PMC7847688 DOI: 10.7150/thno.45889] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 12/02/2020] [Indexed: 12/21/2022] Open
Abstract
Pin1 belongs to the peptidyl-prolyl cis-trans isomerases (PPIases) superfamily and catalyzes the cis-trans conversion of proline in target substrates to modulate diverse cellular functions including cell cycle progression, cell motility, and apoptosis. Dysregulation of Pin1 has wide-ranging influences on the fate of cells; therefore, it is closely related to the occurrence and development of various diseases. This review summarizes the current knowledge of Pin1 in disease pathogenesis.
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Affiliation(s)
- Jingyi Li
- The Second Affiliated Hospital of Chengdu Medical College, China National Nuclear Corporation 416 Hospital, Chengdu, Sichuan, China
- School of Biological Sciences and Technology, Chengdu Medical College, Chengdu, China
| | - Chunfen Mo
- Department of Immunology, School of Basic Medical Sciences, Chengdu Medical College, Chengdu, China
| | - Yifan Guo
- School of Biological Sciences and Technology, Chengdu Medical College, Chengdu, China
| | - Bowen Zhang
- The Second Affiliated Hospital of Chengdu Medical College, China National Nuclear Corporation 416 Hospital, Chengdu, Sichuan, China
| | - Xiao Feng
- School of Biological Sciences and Technology, Chengdu Medical College, Chengdu, China
| | - Qiuyue Si
- School of Biological Sciences and Technology, Chengdu Medical College, Chengdu, China
| | - Xiaobo Wu
- School of Biological Sciences and Technology, Chengdu Medical College, Chengdu, China
| | - Zhe Zhao
- School of Biological Sciences and Technology, Chengdu Medical College, Chengdu, China
| | - Lixin Gong
- The Second Affiliated Hospital of Chengdu Medical College, China National Nuclear Corporation 416 Hospital, Chengdu, Sichuan, China
| | - Dan He
- The Second Affiliated Hospital of Chengdu Medical College, China National Nuclear Corporation 416 Hospital, Chengdu, Sichuan, China
| | - Jichun Shao
- The Second Affiliated Hospital of Chengdu Medical College, China National Nuclear Corporation 416 Hospital, Chengdu, Sichuan, China
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12
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Hulshof EC, Lim L, de Hingh IHJT, Gelderblom H, Guchelaar HJ, Deenen MJ. Genetic Variants in DNA Repair Pathways as Potential Biomarkers in Predicting Treatment Outcome of Intraperitoneal Chemotherapy in Patients With Colorectal Peritoneal Metastasis: A Systematic Review. Front Pharmacol 2020; 11:577968. [PMID: 33117169 PMCID: PMC7575928 DOI: 10.3389/fphar.2020.577968] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 08/27/2020] [Indexed: 12/18/2022] Open
Abstract
Background The introduction of cytoreductive surgery (CRS) followed by hyperthermic intraperitoneal chemotherapy (HIPEC) with either oxaliplatin or mitomycin C for patients with colorectal peritoneal metastasis (CPM) has resulted in a major increase in overall survival. Nonetheless, despite critical patient selection, the majority of patients will develop recurrent disease within one year following CRS + HIPEC. Therefore, improvement of patient and treatment selection is needed and may be achieved by the incorporation of genetic biomarkers. This systematic review aims to provide an overview of genetic biomarkers in the DNA repair pathway that are potentially predictive for treatment outcome of patients with colorectal peritoneal metastases treated with CRS + HIPEC with oxaliplatin or mitomycin C. Methods A systematic review was conducted according to the PRISMA guidelines. Given the limited number of genetic association studies of intraperitoneal mitomycin C and oxaliplatin in patients with CPM, we expanded the review and extrapolated the data from biomarker studies conducted in colorectal cancer patients treated with systemic mitomycin C– and oxaliplatin-based chemotherapy. Results In total, 43 papers were included in this review. No study reported potential pharmacogenomic biomarkers in patients with colorectal cancer undergoing mitomycin C–based chemotherapy. For oxaliplatin-based chemotherapy, a total of 26 genetic biomarkers within 14 genes were identified that were significantly associated with treatment outcome. The most promising genetic biomarkers were ERCC1 rs11615, XPC rs1043953, XPD rs13181, XPG rs17655, MNAT rs3783819/rs973063/rs4151330, MMR status, ATM protein expression, HIC1 tandem repeat D17S5, and PIN1 rs2233678. Conclusion Several genetic biomarkers have proven predictive value for the treatment outcome of systemically administered oxaliplatin. By extrapolation, these genetic biomarkers may also be predictive for the efficacy of intraperitoneal oxaliplatin. This should be the subject of further investigation.
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Affiliation(s)
- Emma C Hulshof
- Department of Clinical Pharmacy, Catharina Hospital, Eindhoven, Netherlands.,Department of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, Netherlands
| | - Lifani Lim
- Department of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, Netherlands
| | - Ignace H J T de Hingh
- Department of Surgical Oncology, Catharina Hospital, Eindhoven, Netherlands.,GROW, School for Oncology and Development Biology, Maastricht University, Maastricht, Netherlands
| | - Hans Gelderblom
- Department of Medical Oncology, Leiden University Medical Center, Leiden, Netherlands
| | - Henk-Jan Guchelaar
- Department of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, Netherlands.,Leiden Network for Personalized Therapeutics, Leiden, Netherlands
| | - Maarten J Deenen
- Department of Clinical Pharmacy, Catharina Hospital, Eindhoven, Netherlands.,Department of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, Netherlands
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13
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Mozaffari NL, Pagliarulo F, Sartori AA. Human CtIP: A 'double agent' in DNA repair and tumorigenesis. Semin Cell Dev Biol 2020; 113:47-56. [PMID: 32950401 DOI: 10.1016/j.semcdb.2020.09.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 07/20/2020] [Accepted: 09/02/2020] [Indexed: 12/14/2022]
Abstract
Human CtIP was originally identified as an interactor of the retinoblastoma protein and BRCA1, two bona fide tumour suppressors frequently mutated in cancer. CtIP is renowned for its role in the resection of DNA double-strand breaks (DSBs) during homologous recombination, a largely error-free DNA repair pathway crucial in maintaining genome integrity. However, CtIP-dependent DNA end resection is equally accountable for alternative end-joining, a mutagenic DSB repair mechanism implicated in oncogenic chromosomal translocations. In addition, CtIP contributes to transcriptional regulation of G1/S transition, DNA damage checkpoint signalling, and replication fork protection pathways. In this review, we present a perspective on the current state of knowledge regarding the tumour-suppressive and oncogenic properties of CtIP and provide an overview of their relevance for cancer development, progression, and therapy.
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Affiliation(s)
- Nour L Mozaffari
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
| | - Fabio Pagliarulo
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
| | - Alessandro A Sartori
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland.
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14
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Yang H, Ren S, Yu S, Pan H, Li T, Ge S, Zhang J, Xia N. Methods Favoring Homology-Directed Repair Choice in Response to CRISPR/Cas9 Induced-Double Strand Breaks. Int J Mol Sci 2020; 21:E6461. [PMID: 32899704 PMCID: PMC7555059 DOI: 10.3390/ijms21186461] [Citation(s) in RCA: 78] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 08/20/2020] [Accepted: 09/01/2020] [Indexed: 12/15/2022] Open
Abstract
Precise gene editing is-or will soon be-in clinical use for several diseases, and more applications are under development. The programmable nuclease Cas9, directed by a single-guide RNA (sgRNA), can introduce double-strand breaks (DSBs) in target sites of genomic DNA, which constitutes the initial step of gene editing using this novel technology. In mammals, two pathways dominate the repair of the DSBs-nonhomologous end joining (NHEJ) and homology-directed repair (HDR)-and the outcome of gene editing mainly depends on the choice between these two repair pathways. Although HDR is attractive for its high fidelity, the choice of repair pathway is biased in a biological context. Mammalian cells preferentially employ NHEJ over HDR through several mechanisms: NHEJ is active throughout the cell cycle, whereas HDR is restricted to S/G2 phases; NHEJ is faster than HDR; and NHEJ suppresses the HDR process. This suggests that definitive control of outcome of the programmed DNA lesioning could be achieved through manipulating the choice of cellular repair pathway. In this review, we summarize the DSB repair pathways, the mechanisms involved in choice selection based on DNA resection, and make progress in the research investigating strategies that favor Cas9-mediated HDR based on the manipulation of repair pathway choice to increase the frequency of HDR in mammalian cells. The remaining problems in improving HDR efficiency are also discussed. This review should facilitate the development of CRISPR/Cas9 technology to achieve more precise gene editing.
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Affiliation(s)
| | | | | | | | - Tingdong Li
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Disease, Collaborative Innovation Centers of Biological Products, School of Public Health, Xiamen University, Xiamen 361102, China; (H.Y.); (S.R.); (S.Y.); (H.P.); (J.Z.); (N.X.)
| | - Shengxiang Ge
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, National Institute of Diagnostics and Vaccine Development in Infectious Disease, Collaborative Innovation Centers of Biological Products, School of Public Health, Xiamen University, Xiamen 361102, China; (H.Y.); (S.R.); (S.Y.); (H.P.); (J.Z.); (N.X.)
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15
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Li F, Mladenov E, Mortoga S, Iliakis G. SCF SKP2 regulates APC/C CDH1-mediated degradation of CTIP to adjust DNA-end resection in G 2-phase. Cell Death Dis 2020; 11:548. [PMID: 32683422 PMCID: PMC7368859 DOI: 10.1038/s41419-020-02755-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 06/22/2020] [Accepted: 06/25/2020] [Indexed: 11/20/2022]
Abstract
The cell cycle-dependent engagement of DNA-end resection at DSBs is regulated by phosphorylation of CTIP by CDKs, the central regulators of cell cycle transitions. Cell cycle transitions are also intimately regulated by protein degradation via two E3 ubiquitin ligases: SCFSKP2 and APC/CCDH1 complex. Although APC/CCDH1 regulates CTIP in G1– and G2-phase, contributions by SCFSKP2 have not been reported. We demonstrate that SCFSKP2 is a strong positive regulator of resection. Knockdown of SKP2, fully suppresses resection in several cell lines. Notably, this suppression is G2-phase specific and is not observed in S-phase or G1–phase cells. Knockdown of SKP2 inactivates SCFSKP2 causing APC/CCDH1 activation, which degrades CTIP. The stabilizing function of SCFSKP2 on CTIP promotes resection and supports gene conversion (GC), alternative end joining (alt-EJ) and cell survival. We propose that CDKs and SCFSKP2-APC/CCDH1 cooperate to regulate resection and repair pathway choice at DSBs in G2-phase.
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Affiliation(s)
- Fanghua Li
- Institute of Medical Radiation Biology, University of Duisburg-Essen Medical School, 45122, Essen, Germany
| | - Emil Mladenov
- Institute of Medical Radiation Biology, University of Duisburg-Essen Medical School, 45122, Essen, Germany
| | - Sharif Mortoga
- Institute of Medical Radiation Biology, University of Duisburg-Essen Medical School, 45122, Essen, Germany
| | - George Iliakis
- Institute of Medical Radiation Biology, University of Duisburg-Essen Medical School, 45122, Essen, Germany.
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16
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Mejías-Navarro F, Rodríguez-Real G, Ramón J, Camarillo R, Huertas P. ALC1/eIF4A1-mediated regulation of CtIP mRNA stability controls DNA end resection. PLoS Genet 2020; 16:e1008787. [PMID: 32392243 PMCID: PMC7241833 DOI: 10.1371/journal.pgen.1008787] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 05/21/2020] [Accepted: 04/22/2020] [Indexed: 11/18/2022] Open
Abstract
During repair of DNA double-strand breaks, resection of DNA ends influences how these lesions will be repaired. If resection is activated, the break will be channeled through homologous recombination; if not, it will be simply ligated using the non-homologous end-joining machinery. Regulation of resection relies greatly on modulating CtIP, which can be done by modifying: i) its interaction partners, ii) its post-translational modifications, or iii) its cellular levels, by regulating transcription, splicing and/or protein stability/degradation. Here, we have analyzed the role of ALC1, a chromatin remodeler previously described as an integral part of the DNA damage response, in resection. Strikingly, we found that ALC1 affects resection independently of chromatin remodeling activity or its ability to bind damaged chromatin. In fact, it cooperates with the RNA-helicase eIF4A1 to help stabilize the most abundant splicing form of CtIP mRNA. This function relies on the presence of a specific RNA sequence in the 5' UTR of CtIP. Therefore, we describe an additional layer of regulation of CtIP-at the level of mRNA stability through ALC1 and eIF4A1.
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Affiliation(s)
- Fernando Mejías-Navarro
- Department of Genetics, University of Seville, Sevilla, Spain
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, Sevilla, Spain
| | - Guillermo Rodríguez-Real
- Department of Genetics, University of Seville, Sevilla, Spain
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, Sevilla, Spain
| | - Javier Ramón
- Department of Genetics, University of Seville, Sevilla, Spain
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, Sevilla, Spain
| | - Rosa Camarillo
- Department of Genetics, University of Seville, Sevilla, Spain
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, Sevilla, Spain
| | - Pablo Huertas
- Department of Genetics, University of Seville, Sevilla, Spain
- Centro Andaluz de Biología Molecular y Medicina Regenerativa-CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, Sevilla, Spain
- * E-mail:
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17
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Makinwa Y, Musich PR, Zou Y. Phosphorylation-Dependent Pin1 Isomerization of ATR: Its Role in Regulating ATR's Anti-apoptotic Function at Mitochondria, and the Implications in Cancer. Front Cell Dev Biol 2020; 8:281. [PMID: 32426354 PMCID: PMC7203486 DOI: 10.3389/fcell.2020.00281] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 03/31/2020] [Indexed: 12/11/2022] Open
Abstract
Peptidyl-prolyl isomerization is an important post-translational modification of protein because proline is the only amino acid that can stably exist as cis and trans, while other amino acids are in the trans conformation in protein backbones. This makes prolyl isomerization a unique mechanism for cells to control many cellular processes. Isomerization is a rate-limiting process that requires a peptidyl-prolyl cis/trans isomerase (PPIase) to overcome the energy barrier between cis and trans isomeric forms. Pin1, a key PPIase in the cell, recognizes a phosphorylated Ser/Thr-Pro motif to catalyze peptidyl-prolyl isomerization in proteins. The significance of the phosphorylation-dependent Pin1 activity was recently highlighted for isomerization of ATR (ataxia telangiectasia- and Rad3-related). ATR, a PIKK protein kinase, plays a crucial role in DNA damage responses (DDR) by phosphorylating hundreds of proteins. ATR can form cis or trans isomers in the cytoplasm depending on Pin1 which isomerizes cis-ATR to trans-ATR. Trans-ATR functions primarily in the nucleus. The cis-ATR, containing an exposed BH3 domain, is anti-apoptotic at mitochondria by binding to tBid, preventing activation of pro-apoptotic Bax. Given the roles of apoptosis in many human diseases, particularly cancer, we propose that cytoplasmic cis-ATR enables cells to evade apoptosis, thus addicting cancer cells to cis-ATR formation for survival. But in normal DDR, a predominance of trans-ATR in the nucleus coordinates with a minimal level of cytoplasmic cis-ATR to promote DNA repair while preventing cell death; however, cells can die when DNA repair fails. Therefore, a delicate balance/equilibrium of the levels of cis- and trans-ATR is required to ensure the cellular homeostasis. In this review, we make a case that this anti-apoptotic role of cis-ATR supports oncogenesis, while Pin1 that drives the formation of trans-ATR suppresses tumor growth. We offer a potential, novel target that can be specifically targeted in cancer cells, without killing normal cells, to significantly reduce the adverse effects usually seen in cancer treatment. We also raise important issues regarding the roles of phosphorylation-dependent Pin1 isomerization of ATR in diseases and propose areas of future studies that would shed more understanding on this important cellular mechanism.
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Affiliation(s)
- Yetunde Makinwa
- Department of Cancer Biology, University of Toledo College of Medicine, Toledo, OH, United States
| | - Phillip R Musich
- Department of Biomedical Sciences, JH Quillen College of Medicine, East Tennessee State University, Johnson City, TN, United States
| | - Yue Zou
- Department of Cancer Biology, University of Toledo College of Medicine, Toledo, OH, United States.,Department of Biomedical Sciences, JH Quillen College of Medicine, East Tennessee State University, Johnson City, TN, United States
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18
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Knowlson C, Haddock P, Bingham V, McQuaid S, Mullan PB, Buckley NE. Pin1 plays a key role in the response to treatment and clinical outcome in triple negative breast cancer. Ther Adv Med Oncol 2020; 12:1758835920906047. [PMID: 32215056 PMCID: PMC7065279 DOI: 10.1177/1758835920906047] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 01/22/2020] [Indexed: 11/22/2022] Open
Abstract
Background: Triple negative breast cancer (TNBC) is the subset of breast cancer associated with the poorest outcome, and currently lacks targeted treatments. Standard of care (SoC) chemotherapy often consists of DNA damaging chemotherapies ± taxanes, with a range of responses observed. However, we currently lack biomarkers to predict this response and lack alternate treatment options. Methods: Pin1 expression was modulated in vitro and proliferation and treatment response was studied. Pin1 expression was analysed in patient samples and correlated with clinical outcome. Results: In this study, we have shown that the prolyl isomerase, Pin1, which is highly expressed in TNBC, plays a key role in pathogenesis of the disease. Knockdown of Pin1 in TNBC resulted in cell death while the opposite is seen in normal cells. We revealed for the first time that loss of Pin1 leads to increased sensitivity to Taxol but only in the absence of functional BRCA1. Conversely, loss of Pin1 results in decreased sensitivity to DNA-damaging agents independent of BRCA1 status. Analysis of Pin1 gene or IHC-based expression in over 200 TNBC patient samples revealed a novel role for Pin1 as a TNBC-specific biomarker, with high expression associated with improved outcome in the context of SoC chemotherapy. Preliminary data indicated this may be extended to other treatment options (e.g. Cisplatin/Parp Inhibitors) that are gaining traction for the treatment of TNBC. Conclusions: This study highlights the important role played by Pin1 in TNBC and highlights the context-dependent functions in modulating cell growth and response to treatment.
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Affiliation(s)
- Catherine Knowlson
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, UK
| | - Paula Haddock
- School of Pharmacy, Queen's University Belfast, Belfast, UK
| | - Victoria Bingham
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, UK
| | - Stephen McQuaid
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, UK
| | - Paul B Mullan
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, UK
| | - Niamh E Buckley
- School of Pharmacy, Queen's University Belfast, 97 Lisburn Rd, Belfast, BT9 7BL, UK
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19
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Luo ML, Zheng F, Chen W, Liang ZM, Chandramouly G, Tan J, Willis NA, Chen CH, Taveira MDO, Zhou XZ, Lu KP, Scully R, Wulf GM, Hu H. Inactivation of the Prolyl Isomerase Pin1 Sensitizes BRCA1-Proficient Breast Cancer to PARP Inhibition. Cancer Res 2020; 80:3033-3045. [PMID: 32193285 DOI: 10.1158/0008-5472.can-19-2739] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Revised: 12/23/2019] [Accepted: 03/13/2020] [Indexed: 02/07/2023]
Abstract
PARP inhibitor monotherapies are effective to treat patients with breast, ovary, prostate, and pancreatic cancer with BRCA1 mutations, but not to the much more frequent BRCA wild-type cancers. Searching for strategies that would extend the use of PARP inhibitors to BRCA1-proficient tumors, we found that the stability of BRCA1 protein following ionizing radiation (IR) is maintained by postphosphorylational prolyl-isomerization adjacent to Ser1191 of BRCA1, catalyzed by prolyl-isomerase Pin1. Extinction of Pin1 decreased homologous recombination (HR) to the level of BRCA1-deficient cells. Pin1 stabilizes BRCA1 by preventing ubiquitination of Lys1037 of BRCA1. Loss of Pin1, or introduction of a BRCA1-mutant refractory to Pin1 binding, decreased the ability of BRCA1 to localize to repair foci and augmented IR-induced DNA damage. In vitro growth of HR-proficient breast, prostate, and pancreatic cancer cells were modestly repressed by olaparib or Pin1 inhibition using all-trans retinoic acid (ATRA), while combination treatment resulted in near-complete block of cell proliferation. In MDA-MB-231 xenografts and triple-negative breast cancer patient-derived xenografts, either loss of Pin1 or ATRA treatment reduced BRCA1 expression and sensitized breast tumors to olaparib. Together, our study reveals that Pin1 inhibition, with clinical widely used ATRA, acts as an effective HR disrupter that sensitizes BRCA1-proficient tumors to PARP inhibition. SIGNIFICANCE: PARP inhibitors have been limited to treat homologous recombination-deficient tumors. All-trans retinoic acid, by inhibiting Pin1 and destabilizing BRCA1, extends benefit of PARP inhibitors to patients with homologous recombination-proficient tumors.See related commentary by Cai, p. 2977.
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Affiliation(s)
- Man-Li Luo
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Fang Zheng
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Wenying Chen
- Department of Oncology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Zhi-Mei Liang
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Gurushankar Chandramouly
- Department of Medicine, Division of Hematology-Oncology and Cancer Research Institute, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts
| | - Jianan Tan
- Department of Oncology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Nicholas A Willis
- Department of Medicine, Division of Hematology-Oncology and Cancer Research Institute, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts
| | - Chun-Hau Chen
- Division of Translational Therapeutics, Department of Medicine and Cancer Research Institute, Center for Life Science, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Mateus de Oliveira Taveira
- Department of Medicine, Division of Hematology-Oncology and Cancer Research Institute, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts
| | - Xiao Zhen Zhou
- Division of Translational Therapeutics, Department of Medicine and Cancer Research Institute, Center for Life Science, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Kun Ping Lu
- Division of Translational Therapeutics, Department of Medicine and Cancer Research Institute, Center for Life Science, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Ralph Scully
- Department of Medicine, Division of Hematology-Oncology and Cancer Research Institute, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts
| | - Gerburg M Wulf
- Department of Medicine, Division of Hematology-Oncology and Cancer Research Institute, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts.
| | - Hai Hu
- Department of Oncology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.
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20
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Jimenez JJ, Chale RS, Abad AC, Schally AV. Acute promyelocytic leukemia (APL): a review of the literature. Oncotarget 2020; 11:992-1003. [PMID: 32215187 PMCID: PMC7082115 DOI: 10.18632/oncotarget.27513] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 02/17/2020] [Indexed: 12/15/2022] Open
Abstract
Acute Promyelocytic Leukemia (APL) is characterized by a block in differentiation where leukemic cells are halted at the promyelocyte stage. A characteristic balanced chromosomal translocation between chromosomes 15 and 17 t (15;17) (q24; q21) is seen in 95% of cases — the translocation results in the formation of the PML-RARA fusion protein. The introduction of retinoic acid (RA) and arsenic trioxide (ATO) has been responsible for initially remarkable cure rates. However, relapsed APL, particularly in the high-risk subset of patients, remains an important clinical problem. In addition, despite the success of ATRA & ATO, many clinicians still elect to use cytotoxic chemotherapy in the treatment of APL. Patients who become resistant to ATO have an increased risk of mortality. The probability of relapse is significantly higher in the high-risk subset of patients undergoing treatment for APL; overall approximately 10-20% of APL patients relapse regardless of their risk stratification. Furthermore, 20-25% of patients undergoing treatment will develop differentiation syndrome, a common side effect of differentiation agents. Recent evidence using in vitro models has shown that mutations in the B2 domain of the PML protein, mediate arsenic resistance. Alternative agents and approaches considering these clinical outcomes are needed to address ATO resistance as well as the relapse rate in high risk APL.
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Affiliation(s)
- Joaquin J Jimenez
- Dr. Phillip Frost Department of Dermatology, Miller School of Medicine, University of Miami, Miami, FL, USA.,Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Ravinder S Chale
- Dr. Phillip Frost Department of Dermatology, Miller School of Medicine, University of Miami, Miami, FL, USA.,Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Andrea C Abad
- Dr. Phillip Frost Department of Dermatology, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Andrew V Schally
- Division of Endocrinology, Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL, USA.,Endocrine, Polypeptide and Cancer Institute, Veterans Affairs Medical Center, Miami, FL, USA.,Department of Medicine, Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL, USA.,Division of Hematology Oncology, Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL, USA.,Department of Pathology, Miller School of Medicine, University of Miami, Miami, FL, USA
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21
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Daza-Martin M, Starowicz K, Jamshad M, Tye S, Ronson GE, MacKay HL, Chauhan AS, Walker AK, Stone HR, Beesley JFJ, Coles JL, Garvin AJ, Stewart GS, McCorvie TJ, Zhang X, Densham RM, Morris JR. Isomerization of BRCA1-BARD1 promotes replication fork protection. Nature 2019; 571:521-527. [PMID: 31270457 DOI: 10.1038/s41586-019-1363-4] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 06/03/2019] [Indexed: 01/01/2023]
Abstract
The integrity of genomes is constantly threatened by problems encountered by the replication fork. BRCA1, BRCA2 and a subset of Fanconi anaemia proteins protect stalled replication forks from degradation by nucleases, through pathways that involve RAD51. The contribution and regulation of BRCA1 in replication fork protection, and how this role relates to its role in homologous recombination, is unclear. Here we show that BRCA1 in complex with BARD1, and not the canonical BRCA1-PALB2 interaction, is required for fork protection. BRCA1-BARD1 is regulated by a conformational change mediated by the phosphorylation-directed prolyl isomerase PIN1. PIN1 activity enhances BRCA1-BARD1 interaction with RAD51, thereby increasing the presence of RAD51 at stalled replication structures. We identify genetic variants of BRCA1-BARD1 in patients with cancer that exhibit poor protection of nascent strands but retain homologous recombination proficiency, thus defining domains of BRCA1-BARD1 that are required for fork protection and associated with cancer development. Together, these findings reveal a BRCA1-mediated pathway that governs replication fork protection.
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Affiliation(s)
- Manuel Daza-Martin
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
- The Institute of Cancer Research, Chester Beatty Laboratories, London, UK
| | - Katarzyna Starowicz
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - Mohammed Jamshad
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - Stephanie Tye
- Section of Structural Biology, Department of Medicine, Imperial College London, London, UK
| | - George E Ronson
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - Hannah L MacKay
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - Anoop Singh Chauhan
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - Alexandra K Walker
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - Helen R Stone
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - James F J Beesley
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - Jennifer L Coles
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
- Warwick Medical School, The University of Warwick, Coventry, UK
| | - Alexander J Garvin
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - Grant S Stewart
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - Thomas J McCorvie
- Section of Structural Biology, Department of Medicine, Imperial College London, London, UK
| | - Xiaodong Zhang
- Section of Structural Biology, Department of Medicine, Imperial College London, London, UK
| | - Ruth M Densham
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK.
| | - Joanna R Morris
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK.
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Saidi L, Rocha DHA, Talhi O, Bentarzi Y, Nedjar‐Kolli B, Bachari K, Almeida Paz FA, Helguero LA, Silva AMS. Synthesis of Benzophenones and in vitro Evaluation of Their Anticancer Potential in Breast and Prostate Cancer Cells. ChemMedChem 2019; 14:1041-1048. [DOI: 10.1002/cmdc.201900127] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 03/31/2019] [Indexed: 12/24/2022]
Affiliation(s)
- Lydia Saidi
- Laboratory of Applied Organic Chemistry, Faculty of ChemistryHouari Boumediene University of Sciences and Technology, USTHB, BP 32, El-Alia Bab-Ezzouar 16111 Algiers Algeria
| | - Djenisa H. A. Rocha
- QOPNA and LAQV-REQUIMTE, Department of ChemistryUniversity of Aveiro 3810-193 Aveiro Portugal
- Institute of Biomedicine (iBiMED)Department of Medical SciencesUniversity of Aveiro 3810-193 Aveiro Portugal
| | - Oualid Talhi
- QOPNA and LAQV-REQUIMTE, Department of ChemistryUniversity of Aveiro 3810-193 Aveiro Portugal
- Centre de Recherche Scientifique et Technique en Analyses Physico-Chimiques (CRAPC) BP384 Bou-Ismail 42004 Tipaza Algeria
| | - Yamina Bentarzi
- Laboratory of Applied Organic Chemistry, Faculty of ChemistryHouari Boumediene University of Sciences and Technology, USTHB, BP 32, El-Alia Bab-Ezzouar 16111 Algiers Algeria
| | - Bellara Nedjar‐Kolli
- Laboratory of Applied Organic Chemistry, Faculty of ChemistryHouari Boumediene University of Sciences and Technology, USTHB, BP 32, El-Alia Bab-Ezzouar 16111 Algiers Algeria
| | - Khaldoun Bachari
- Centre de Recherche Scientifique et Technique en Analyses Physico-Chimiques (CRAPC) BP384 Bou-Ismail 42004 Tipaza Algeria
| | | | - Luisa A. Helguero
- Institute of Biomedicine (iBiMED)Department of Medical SciencesUniversity of Aveiro 3810-193 Aveiro Portugal
| | - Artur M. S. Silva
- QOPNA and LAQV-REQUIMTE, Department of ChemistryUniversity of Aveiro 3810-193 Aveiro Portugal
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Zannini A, Rustighi A, Campaner E, Del Sal G. Oncogenic Hijacking of the PIN1 Signaling Network. Front Oncol 2019; 9:94. [PMID: 30873382 PMCID: PMC6401644 DOI: 10.3389/fonc.2019.00094] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 02/01/2019] [Indexed: 12/18/2022] Open
Abstract
Cellular choices are determined by developmental and environmental stimuli through integrated signal transduction pathways. These critically depend on attainment of proper activation levels that in turn rely on post-translational modifications (PTMs) of single pathway members. Among these PTMs, post-phosphorylation prolyl-isomerization mediated by PIN1 represents a unique mechanism of spatial, temporal and quantitative control of signal transduction. Indeed PIN1 was shown to be crucial for determining activation levels of several pathways and biological outcomes downstream to a plethora of stimuli. Of note, studies performed in different model organisms and humans have shown that hormonal, nutrient, and oncogenic stimuli simultaneously affect both PIN1 activity and the pathways that depend on PIN1-mediated prolyl-isomerization, suggesting the existence of evolutionarily conserved molecular circuitries centered on this isomerase. This review focuses on molecular mechanisms and cellular processes like proliferation, metabolism, and stem cell fate, that are regulated by PIN1 in physiological conditions, discussing how these are subverted in and hijacked by cancer cells. Current status and open questions regarding the use of PIN1 as biomarker and target for cancer therapy as well as clinical development of PIN1 inhibitors are also addressed.
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Affiliation(s)
- Alessandro Zannini
- National Laboratory CIB, Trieste, Italy.,Department of Life Sciences, University of Trieste, Trieste, Italy
| | - Alessandra Rustighi
- National Laboratory CIB, Trieste, Italy.,Department of Life Sciences, University of Trieste, Trieste, Italy
| | | | - Giannino Del Sal
- National Laboratory CIB, Trieste, Italy.,Department of Life Sciences, University of Trieste, Trieste, Italy.,IFOM - Istituto FIRC Oncologia Molecolare, Milan, Italy
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Wang J, Chan B, Tong M, Paung Y, Jo U, Martin D, Seeliger M, Haley J, Kim H. Prolyl isomerization of FAAP20 catalyzed by PIN1 regulates the Fanconi anemia pathway. PLoS Genet 2019; 15:e1007983. [PMID: 30789902 PMCID: PMC6400411 DOI: 10.1371/journal.pgen.1007983] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 03/05/2019] [Accepted: 01/23/2019] [Indexed: 01/27/2023] Open
Abstract
The Fanconi Anemia (FA) pathway is a multi-step DNA repair process at stalled replication forks in response to DNA interstrand cross-links (ICLs). Pathological mutation of key FA genes leads to the inherited disorder FA, characterized by progressive bone marrow failure and cancer predisposition. The study of FA is of great importance not only to children suffering from FA but also as a model to study cancer pathogenesis in light of genome instability among the general population. FANCD2 monoubiquitination by the FA core complex is an essential gateway that connects upstream DNA damage signaling to enzymatic steps of repair. FAAP20 is a key component of the FA core complex, and regulated proteolysis of FAAP20 mediated by the ubiquitin E3 ligase SCFFBW7 is critical for maintaining the integrity of the FA complex and FA pathway signaling. However, upstream regulatory mechanisms that govern this signaling remain unclear. Here, we show that PIN1, a phosphorylation-specific prolyl isomerase, regulates the integrity of the FA core complex, thus FA pathway activation. We demonstrate that PIN1 catalyzes cis-trans isomerization of the FAAP20 pSer48-Pro49 motif and promotes FAAP20 stability. Mechanistically, PIN1-induced conformational change of FAAP20 enhances its interaction with the PP2A phosphatase to counteract SCFFBW7-dependent proteolytic signaling at the phosphorylated degron motif. Accordingly, PIN1 deficiency impairs FANCD2 activation and the DNA ICL repair process. Together, our study establishes PIN1-dependent prolyl isomerization as a new regulator of the FA pathway and genomic integrity. Fanconi anemia (FA) is a devastating disease of children that leads to birth defects, bone marrow failure, and a variety of cancers early in their lives. Germ-line mutations in FA genes disrupt the DNA repair process, namely the FA pathway, resulting in genome instability and clinical features of FA patients. Thus, understanding the molecular mechanisms by which the FA pathway is regulated is critical for alleviating the burden of children suffering from FA and related cancer. A critical step in this pathway is the monoubiquitination of FANCD2 by a multi-subunit ubiquitin E3 ligase called the FA core complex, and the FAAP20 subunit is required for its functional integrity. Here, we show that proline-directed structural change of FAAP20 catalyzed by the PIN1 prolyl cis-trans isomerase is essential for the FAAP20 stability by counteracting phosphorylation-dependent proteolytic signaling of FAAP20 and thus promotes FANCD2 activation and DNA repair. Our findings reveal how PIN1-mediated phosphorylation signaling cascade and proteolysis preserves genomic integrity and how its deregulation is associated the pathogenesis of FA. Our knowledge on a new regulatory mechanism governing FA pathway activation may lead to the development of a new target for FA and FA-related malignancy.
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Affiliation(s)
- Jingming Wang
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, United States of America
| | - Bryan Chan
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, United States of America
| | - Michael Tong
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, United States of America
| | - YiTing Paung
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, United States of America
- Department of Chemistry, Stony Brook University, Stony Brook, New York, United States of America
| | - Ukhyun Jo
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, United States of America
| | - Dwight Martin
- Department of Pathology, Proteomics Center, Stony Brook University, Stony Brook, New York, United States of America
| | - Markus Seeliger
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, United States of America
- Stony Brook Cancer Center, Stony Brook University School of Medicine, Stony Brook, New York, United States of America
| | - John Haley
- Department of Pathology, Proteomics Center, Stony Brook University, Stony Brook, New York, United States of America
- Stony Brook Cancer Center, Stony Brook University School of Medicine, Stony Brook, New York, United States of America
| | - Hyungjin Kim
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York, United States of America
- Stony Brook Cancer Center, Stony Brook University School of Medicine, Stony Brook, New York, United States of America
- * E-mail:
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Prognosis value of RBBP8 expression in plasma cell myeloma. Cancer Gene Ther 2019; 27:22-29. [PMID: 30622325 PMCID: PMC7027984 DOI: 10.1038/s41417-018-0069-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 10/30/2018] [Accepted: 11/02/2018] [Indexed: 12/01/2022]
Abstract
Plasma cell myeloma (PCM) secretes monoclonal immunoglobulin (Ig) by clonal plasma cells of abnormal proliferation in the bone marrow. As PCM is incurable, it is necessary to find new biomarkers to predict the prognosis and recurrence of PCM. The relationship between cancer and RBBP8 has not been fully studied. The role of RBBP8 in tumorigenesis remains inconsistent. We described the expression of RBBP8 in the gene expression profile of 1930 PCM samples (1878 PCM patients) from seven independent data sets. We analyzed the relationship between RBBP8 and survival prognosis, recurrence, and treatment response in patients with PCM, and the biological significance of RBBP8 in PCM. The gene expression level of RBBP8 was significantly related to the International staging system (ISS) grade of PCM (P = 0.0012). RBBP8 expression in different molecular subtypes was different (P < 2.2e-16). High RBBP8 expression is associated with poor survival in PCM (P < 0.0001). High expression of RBBP8 indicates that PCM patients are more likely to relapse (P = 0.0078). The biological significance of RBBP8 in PCM is related to the cell cycle (P < 0.05). High RBBP8 expression predicts poorer survival and more likely relapse in PCM. RBBP8 plays an important role in the cell cycle of PCM. RBBP8 can be considered an independent prognostic factor for PCM. RBBP8 can be used as a potential biomarker for assessing the prognosis of PCM patients.
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Jimeno S, Mejías-Navarro F, Prados-Carvajal R, Huertas P. Controlling the balance between chromosome break repair pathways. DNA Repair (Amst) 2019; 115:95-134. [DOI: 10.1016/bs.apcsb.2018.10.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Lee YM, Liou YC. Gears-In-Motion: The Interplay of WW and PPIase Domains in Pin1. Front Oncol 2018; 8:469. [PMID: 30460195 PMCID: PMC6232885 DOI: 10.3389/fonc.2018.00469] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 10/04/2018] [Indexed: 01/22/2023] Open
Abstract
Pin1 belongs to the family of the peptidyl-prolyl cis-trans isomerase (PPIase), which is a class of enzymes that catalyze the cis/trans isomerization of the Proline residue. Pin1 is unique and only catalyzes the phosphorylated Serine/Threonine-Proline (S/T-P) motifs of a subset of proteins. Since the discovery of Pin1 as a key protein in cell cycle regulation, it has been implicated in numerous diseases, ranging from cancer to neurodegenerative diseases. The main features of Pin1 lies in its two main domains: the WW (two conserved tryptophan) domain and the PPIase domain. Despite extensive studies trying to understand the mechanisms of Pin1 functions, how these two domains contribute to the biological roles of Pin1 in cellular signaling requires more investigations. The WW domain of Pin1 is known to have a higher affinity to its substrate than that of the PPIase domain. Yet, the WW domain seems to prefer the trans configuration of phosphorylated S/T-P motif, while the PPIase catalyzes the cis to trans isomerasion. Such contradicting information has generated much confusion as to the actual mechanism of Pin1 function. In addition, dynamic allostery has been suggested to be important for Pin1 function. Henceforth, in this review, we will be looking at the progress made in understanding the function of Pin1, and how these understandings can aid us in overcoming the diseases implicated by Pin1 such as cancer during drug development.
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Affiliation(s)
- Yew Mun Lee
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore
| | - Yih-Cherng Liou
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore
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Wu D, Huang D, Li LL, Ni P, Li XX, Wang B, Han YN, Shao XQ, Zhao D, Chu WF, Li BY. TGF-β1-PML SUMOylation-peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 (Pin1) form a positive feedback loop to regulate cardiac fibrosis. J Cell Physiol 2018; 234:6263-6273. [PMID: 30246389 DOI: 10.1002/jcp.27357] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 08/17/2018] [Indexed: 11/11/2022]
Abstract
Transforming growth factor-β (TGF-β) signaling pathway is involved in fibrosis in most, if not all forms of cardiac diseases. Here, we evaluate a positive feedback signaling the loop of TGF-β1/promyelocytic leukemia (PML) SUMOylation/Pin1 promoting the cardiac fibrosis. To test this hypothesis, the mice underwent transverse aortic constriction (3 weeks) were developed and the morphological evidence showed obvious interstitial fibrosis with TGF-β1, Pin1 upregulation, and increase in PML SUMOylation. In neonatal mouse cardiac fibroblasts (NMCFs), we found that exogenous TGF-β1 induced the upregulation of TGF-β1 itself in a time- and dose-dependent manner, and also triggered the PML SUMOylation and the formation of PML nuclear bodies (PML-NBs), and consequently recruited Pin1 into nuclear to colocalize with PML. Pharmacological inhibition of TGF-β signal or Pin1 with LY364947 (3 μM) or Juglone (3 μM), the TGF-β1-induced PML SUMOylation was reduced significantly with downregulation of the messenger RNA and protein for TGF-β1 and Pin1. To verify the cellular function of PML by means of gain- or loss-of-function, the positive feedback signaling loop was enhanced or declined, meanwhile, TGF-β-Smad signaling pathway was activated or weakened, respectively. In summary, we uncovered a novel reciprocal loop of TGF-β1/PML SUMOylation/Pin1 leading to myocardial fibrosis.
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Affiliation(s)
- Di Wu
- Department of Pharmacology (The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Di Huang
- Department of Pharmacology (The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Liang-Liang Li
- Department of Pharmacology (The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Ping Ni
- Department of Pharmacology (The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Xiu-Xian Li
- Department of Pharmacology (The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Bing Wang
- Department of Pharmacology (The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Yan-Na Han
- Department of Pharmacology (The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Xiao-Qi Shao
- Department of Pharmacology (The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Dan Zhao
- Departments of Clinical Pharmacy and Cardiology, Key Laboratories of Education Ministry for Myocardial Ischemia Mechanism and Treatment, The 2nd Affiliated Hospital, Harbin Medical University, Harbin, China
| | - Wen-Feng Chu
- Department of Pharmacology (The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
| | - Bai-Yan Li
- Department of Pharmacology (The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education), College of Pharmacy, Harbin Medical University, Harbin, China
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Prolyl isomerase Pin1: a promoter of cancer and a target for therapy. Cell Death Dis 2018; 9:883. [PMID: 30158600 PMCID: PMC6115400 DOI: 10.1038/s41419-018-0844-y] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 06/15/2018] [Accepted: 06/27/2018] [Indexed: 12/15/2022]
Abstract
Pin1 is the only known peptidyl-prolyl cis–trans isomerase (PPIase) that specifically recognizes and isomerizes the phosphorylated Serine/Threonine-Proline (pSer/Thr-Pro) motif. The Pin1-mediated structural transformation posttranslationally regulates the biofunctions of multiple proteins. Pin1 is involved in many cellular processes, the aberrance of which lead to both degenerative and neoplastic diseases. Pin1 is highly expressed in the majority of cancers and its deficiency significantly suppresses cancer progression. According to the ground-breaking summaries by Hanahan D and Weinberg RA, the hallmarks of cancer comprise ten biological capabilities. Multiple researches illuminated that Pin1 contributes to these aberrant behaviors of cancer via promoting various cancer-driving pathways. This review summarized the detailed mechanisms of Pin1 in different cancer capabilities and certain Pin1-targeted small-molecule compounds that exhibit anticancer activities, expecting to facilitate anticancer therapies by targeting Pin1.
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Potential role of PIN1 genotypes in predicting benefit from oxaliplatin-based and irinotecan-based treatment in patients with metastatic colorectal cancer. THE PHARMACOGENOMICS JOURNAL 2018; 18:623-632. [PMID: 29925895 PMCID: PMC6151284 DOI: 10.1038/s41397-018-0030-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 02/21/2018] [Accepted: 04/13/2018] [Indexed: 12/22/2022]
Abstract
PIN1-mediated substrate isomerization plays a role in the repair of DNA double-strand breaks. We hypothesized that genetic polymorphisms in PIN1-related pathways may affect tumor sensitivity to oxaliplatin or irinotecan in metastatic colorectal cancer (mCRC) patients. We analyzed genomic DNA from five cohorts of mCRC patients (total 950) treated with different first-line treatments: oxaliplatin cohorts 1 (n=146) and 2 (n=70); irinotecan cohorts 1 (n=228) and 2 (n=276); and combination cohort (n=230). Single nucleotide polymorphisms of candidate genes were analyzed by PCR-based direct sequencing. In the oxaliplatin cohort 1, patients carrying any PIN1 rs2233678 C allele had shorter progression-free survival (PFS) and overall survival (OS) than the G/G variant (PFS, 7.4 vs. 15.0 months, hazard ratio [HR] 3.24, P<0.001; OS, 16.9 vs. 31.5 months, HR: 2.38, P=0.003). In contrast, patients with C allele had longer median PFS than patients with G/G (11.9 vs. 9.4 months, HR: 0.64, 95%CI: 0.45–0.91, P=0.009) in the irinotecan cohort 1. No significant differences were observed in the combination cohort. In comparison between the irinotecan cohort 1 and combination cohort, the patients carrying the G/G variant benefit greatly from the combination compared with irinotecan-based regimen (PFS, 11.6 vs. 9.4 months, HR 0.61, 95%CI: 0.47–0.78, P<0.001; OS, 30.6 vs. 24.0 months, HR 0.79, 95%CI: 0.62–1.02, P=0.060), while no significant difference was shown in any C allele. Germline PIN1 polymorphisms may predict clinical outcomes in mCRC patients receiving oxaliplatin- or irinotecan-based therapy, and identify specific populations favorable to oxaliplatin plus irinotecan combination therapy.
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Cánovas B, Igea A, Sartori AA, Gomis RR, Paull TT, Isoda M, Pérez-Montoyo H, Serra V, González-Suárez E, Stracker TH, Nebreda AR. Targeting p38α Increases DNA Damage, Chromosome Instability, and the Anti-tumoral Response to Taxanes in Breast Cancer Cells. Cancer Cell 2018; 33:1094-1110.e8. [PMID: 29805078 DOI: 10.1016/j.ccell.2018.04.010] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 01/18/2018] [Accepted: 04/25/2018] [Indexed: 12/18/2022]
Abstract
Breast cancer is the second leading cause of cancer-related death among women. Here we report a role for the protein kinase p38α in coordinating the DNA damage response and limiting chromosome instability during breast tumor progression, and identify the DNA repair regulator CtIP as a p38α substrate. Accordingly, decreased p38α signaling results in impaired ATR activation and homologous recombination repair, with concomitant increases in replication stress, DNA damage, and chromosome instability, leading to cancer cell death and tumor regression. Moreover, we show that pharmacological inhibition of p38α potentiates the effects of taxanes by boosting chromosome instability in murine models and patient-derived xenografts, suggesting the potential interest of combining p38α inhibitors with chemotherapeutic drugs that induce chromosome instability.
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Affiliation(s)
- Begoña Cánovas
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology, Barcelona 08028, Spain
| | - Ana Igea
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology, Barcelona 08028, Spain
| | - Alessandro A Sartori
- University of Zurich, Institute of Molecular Cancer Research, Zurich 8057, Switzerland
| | - Roger R Gomis
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology, Barcelona 08028, Spain; ICREA, Pg. Lluís Companys 23, Barcelona 08010, Spain; Universitat de Barcelona and CIBERONC, Barcelona, Spain
| | - Tanya T Paull
- Howard Hughes Medical Institute, University of Texas at Austin, Austin, TX 78712, USA
| | - Michitaka Isoda
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology, Barcelona 08028, Spain
| | - Héctor Pérez-Montoyo
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), Barcelona 08908, Spain
| | - Violeta Serra
- Vall d'Hebron Institute of Oncology (VHIO), Barcelona 08035, Spain
| | - Eva González-Suárez
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), Barcelona 08908, Spain
| | - Travis H Stracker
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology, Barcelona 08028, Spain
| | - Angel R Nebreda
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology, Barcelona 08028, Spain; ICREA, Pg. Lluís Companys 23, Barcelona 08010, Spain.
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33
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Fontana GA, Reinert JK, Thomä NH, Rass U. Shepherding DNA ends: Rif1 protects telomeres and chromosome breaks. MICROBIAL CELL 2018; 5:327-343. [PMID: 29992129 PMCID: PMC6035837 DOI: 10.15698/mic2018.07.639] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cells have evolved conserved mechanisms to protect DNA ends, such as those at the termini of linear chromosomes, or those at DNA double-strand breaks (DSBs). In eukaryotes, DNA ends at chromosomal termini are packaged into proteinaceous structures called telomeres. Telomeres protect chromosome ends from erosion, inadvertent activation of the cellular DNA damage response (DDR), and telomere fusion. In contrast, cells must respond to damage-induced DNA ends at DSBs by harnessing the DDR to restore chromosome integrity, avoiding genome instability and disease. Intriguingly, Rif1 (Rap1-interacting factor 1) has been implicated in telomere homeostasis as well as DSB repair. The protein was first identified in Saccharomyces cerevisiae as being part of the proteinaceous telosome. In mammals, RIF1 is not associated with intact telomeres, but was found at chromosome breaks, where RIF1 has emerged as a key mediator of pathway choice between the two evolutionary conserved DSB repair pathways of non-homologous end-joining (NHEJ) and homologous recombination (HR). While this functional dichotomy has long been a puzzle, recent findings link yeast Rif1 not only to telomeres, but also to DSB repair, and mechanistic parallels likely exist. In this review, we will provide an overview of the actions of Rif1 at DNA ends and explore how exclusion of end-processing factors might be the underlying principle allowing Rif1 to fulfill diverse biological roles at telomeres and chromosome breaks.
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Affiliation(s)
- Gabriele A Fontana
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
| | - Julia K Reinert
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland.,University of Basel, Petersplatz 10, CH-4003 Basel, Switzerland
| | - Nicolas H Thomä
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
| | - Ulrich Rass
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, CH-4058 Basel, Switzerland
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Trenner A, Godau J, Sartori AA. A Short BRCA2-Derived Cell-Penetrating Peptide Targets RAD51 Function and Confers Hypersensitivity toward PARP Inhibition. Mol Cancer Ther 2018; 17:1392-1404. [PMID: 29654063 DOI: 10.1158/1535-7163.mct-17-1156] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 03/01/2018] [Accepted: 04/04/2018] [Indexed: 11/16/2022]
Abstract
Under conditions of genotoxic stress, cancer cells strongly rely on efficient DNA repair to survive and proliferate. The human BRCA2 tumor suppressor protein is indispensable for the repair of DNA double-strand breaks by homologous recombination (HR) by virtue of its ability to promote RAD51 loading onto single-stranded DNA. Therefore, blocking the interaction between BRCA2 and RAD51 could significantly improve the efficacy of conventional anticancer therapies. However, targeting protein-protein interaction (PPI) interfaces has proven challenging because flat and large PPI surfaces generally do not support binding of small-molecule inhibitors. In contrast, peptides are more potent for targeting PPIs but are otherwise difficult to deliver into cells. Here, we report that a synthetic 16-mer peptide derived from the BRC4 repeat motif of BRCA2 is capable of blocking RAD51 binding to BRCA2. Efficient noncytotoxic cellular uptake of a nona-arginine (R9)-conjugated version of the BRC4 peptide interferes with DNA damage-induced RAD51 foci formation and HR. Moreover, transduction of the BRC4 peptide impairs replication fork-protective function of BRCA2 and triggers MRE11-dependent degradation of nascent DNA in response to DNA replication stress. Finally, the BRC4 cell-penetrating peptide (CPP) confers selective hypersensitivity to PARP inhibition in cancer cells but spares noncancerous cells. Taken together, our data highlight an innovative approach to develop novel peptide-based DNA repair inhibitors and establish BRCA2-derived CPPs as promising anticancer agents. Mol Cancer Ther; 17(7); 1392-404. ©2018 AACR.
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Affiliation(s)
- Anika Trenner
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
| | - Julia Godau
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland
| | - Alessandro A Sartori
- Institute of Molecular Cancer Research, University of Zurich, Zurich, Switzerland.
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35
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AUNIP/C1orf135 directs DNA double-strand breaks towards the homologous recombination repair pathway. Nat Commun 2017; 8:985. [PMID: 29042561 PMCID: PMC5645412 DOI: 10.1038/s41467-017-01151-w] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 08/21/2017] [Indexed: 11/26/2022] Open
Abstract
DNA double-strand breaks (DSBs) are mainly repaired by either homologous recombination (HR) or non-homologous end-joining (NHEJ). Here, we identify AUNIP/C1orf135, a largely uncharacterized protein, as a key determinant of DSB repair pathway choice. AUNIP physically interacts with CtIP and is required for efficient CtIP accumulation at DSBs. AUNIP possesses intrinsic DNA-binding ability with a strong preference for DNA substrates that mimic structures generated at stalled replication forks. This ability to bind DNA is necessary for the recruitment of AUNIP and its binding partner CtIP to DSBs, which in turn drives CtIP-dependent DNA-end resection and HR repair. Accordingly, loss of AUNIP or ablation of its ability to bind to DNA results in cell hypersensitivity toward a variety of DSB-inducing agents, particularly those that induce replication-associated DSBs. Our findings provide new insights into the molecular mechanism by which DSBs are recognized and channeled to the HR repair pathway. DNA double strand breaks can be repaired by homology-independent or homology-directed mechanisms. The choice between these pathways is a key event for genomic stability maintenance. Here the authors identify and characterize AUNIP, as a factor involved in tilting the balance towards homology repair.
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Abstract
Vertebrate CtIP, and its fission yeast (Ctp1), budding yeast (Sae2) and plant (Com1) orthologs have emerged as key regulatory molecules in cellular responses to DNA double strand breaks (DSBs). By modulating the nucleolytic 5'-3' resection activity of the Mre11/Rad50/Nbs1 (MRN) DSB repair processing and signaling complex, CtIP/Ctp1/Sae2/Com1 is integral to the channeling of DNA double strand breaks through DSB repair by homologous recombination (HR). Nearly two decades since its discovery, emerging new data are defining the molecular underpinnings for CtIP DSB repair regulatory activities. CtIP homologs are largely intrinsically unstructured proteins comprised of expanded regions of low complexity sequence, rather than defined folded domains typical of DNA damage metabolizing enzymes and nucleases. A compact structurally conserved N-terminus forms a functionally critical tetrameric helical dimer of dimers (THDD) region that bridges CtIP oligomers, and is flexibly appended to a conserved C-terminal Sae2-homology DNA binding and DSB repair pathway choice regulatory hub which influences nucleolytic activities of the MRN core nuclease complex. The emerging evidence from structural, biophysical, and biological studies converges on CtIP having functional roles in DSB repair that include: 1) dynamic DNA strand coordination through direct DNA binding and DNA bridging activities, 2) MRN nuclease complex cofactor functions that direct MRN endonucleolytic cleavage of protein-blocked DSB ends and 3) acting as a protein binding hub targeted by the cell cycle regulatory apparatus, which influences CtIP expression and activity via layers of post-translational modifications, protein-protein interactions and DNA binding.
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Affiliation(s)
- Sara N Andres
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, US National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC 27709, United States
| | - R Scott Williams
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, US National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC 27709, United States.
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37
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Abstract
The correct duplication and transmission of genetic material to daughter cells is the primary objective of the cell division cycle. DNA replication and chromosome segregation present both challenges and opportunities for DNA repair pathways that safeguard genetic information. As a consequence, there is a profound, two-way connection between DNA repair and cell cycle control. Here, we review how DNA repair processes, and DNA double-strand break repair in particular, are regulated during the cell cycle to optimize genomic integrity.
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38
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The role of Pin1 in the development and treatment of cancer. Arch Pharm Res 2016; 39:1609-1620. [PMID: 27572155 DOI: 10.1007/s12272-016-0821-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2016] [Accepted: 08/18/2016] [Indexed: 12/16/2022]
Abstract
Protein phosphorylation and post-phosphorylation events regulate many cellular signaling pathways. Peptidyl-prolyl isomerase (Pin1) is the only peptidyl-prolyl cis/trans isomerase that interacts with numerous oncogenic or tumor suppressive phosphorylated proteins, causes conformational changes in target proteins, and eventually regulates the activities of such proteins. These alterations in activity play a pivotal role in tumorigenesis. Since Pin1 is overexpressed and/or activated in various types of cancers, and the dysregulation of proline-directed phosphorylation contributes to tumorigenesis, Pin1 represents an attractive target for cancer therapy. This review will describe the role of Pin1 in cancer and the current status of Pin1 inhibitor development.
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39
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Cullin3-KLHL15 ubiquitin ligase mediates CtIP protein turnover to fine-tune DNA-end resection. Nat Commun 2016; 7:12628. [PMID: 27561354 PMCID: PMC5007465 DOI: 10.1038/ncomms12628] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 07/19/2016] [Indexed: 12/16/2022] Open
Abstract
Human CtIP is a decisive factor in DNA double-strand break repair pathway choice by enabling DNA-end resection, the first step that differentiates homologous recombination (HR) from non-homologous end-joining (NHEJ). To coordinate appropriate and timely execution of DNA-end resection, CtIP function is tightly controlled by multiple protein-protein interactions and post-translational modifications. Here, we identify the Cullin3 E3 ligase substrate adaptor Kelch-like protein 15 (KLHL15) as a new interaction partner of CtIP and show that KLHL15 promotes CtIP protein turnover via the ubiquitin-proteasome pathway. A tripeptide motif (FRY) conserved across vertebrate CtIP proteins is essential for KLHL15-binding; its mutation blocks KLHL15-dependent CtIP ubiquitination and degradation. Consequently, DNA-end resection is strongly attenuated in cells overexpressing KLHL15 but amplified in cells either expressing a CtIP-FRY mutant or lacking KLHL15, thus impacting the balance between HR and NHEJ. Collectively, our findings underline the key importance and high complexity of CtIP modulation for genome integrity.
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40
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Himmels SF, Sartori AA. Controlling DNA-End Resection: An Emerging Task for Ubiquitin and SUMO. Front Genet 2016; 7:152. [PMID: 27602047 PMCID: PMC4993767 DOI: 10.3389/fgene.2016.00152] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Accepted: 08/05/2016] [Indexed: 12/17/2022] Open
Abstract
DNA double-strand breaks (DSBs) are one of the most detrimental lesions, as their incorrect or incomplete repair can lead to genomic instability, a hallmark of cancer. Cells have evolved two major competing DSB repair mechanisms: Homologous recombination (HR) and non-homologous end joining (NHEJ). HR is initiated by DNA-end resection, an evolutionarily conserved process that generates stretches of single-stranded DNA tails that are no longer substrates for religation by the NHEJ machinery. Ubiquitylation and sumoylation, the covalent attachment of ubiquitin and SUMO moieties to target proteins, play multifaceted roles in DNA damage signaling and have been shown to regulate HR and NHEJ, thus ensuring appropriate DSB repair. Here, we give a comprehensive overview about the current knowledge of how ubiquitylation and sumoylation control DSB repair by modulating the DNA-end resection machinery.
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Affiliation(s)
| | - Alessandro A Sartori
- Institute of Molecular Cancer Research, University of Zurich Zurich, Switzerland
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41
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López-Saavedra A, Gómez-Cabello D, Domínguez-Sánchez MS, Mejías-Navarro F, Fernández-Ávila MJ, Dinant C, Martínez-Macías MI, Bartek J, Huertas P. A genome-wide screening uncovers the role of CCAR2 as an antagonist of DNA end resection. Nat Commun 2016; 7:12364. [PMID: 27503537 PMCID: PMC4980490 DOI: 10.1038/ncomms12364] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 06/27/2016] [Indexed: 01/29/2023] Open
Abstract
There are two major and alternative pathways to repair DNA double-strand breaks: non-homologous end-joining and homologous recombination. Here we identify and characterize novel factors involved in choosing between these pathways; in this study we took advantage of the SeeSaw Reporter, in which the repair of double-strand breaks by homology-independent or -dependent mechanisms is distinguished by the accumulation of green or red fluorescence, respectively. Using a genome-wide human esiRNA (endoribonuclease-prepared siRNA) library, we isolate genes that control the recombination/end-joining ratio. Here we report that two distinct sets of genes are involved in the control of the balance between NHEJ and HR: those that are required to facilitate recombination and those that favour NHEJ. This last category includes CCAR2/DBC1, which we show inhibits recombination by limiting the initiation and the extent of DNA end resection, thereby acting as an antagonist of CtIP. A DNA double strand break can be repaired through either the non-homologous end-joining or the homologous recombination pathways. Here the authors conduct a genome-wide screen and identify a role for CCAR2 in pathway choice by regulating DNA end resection by CtIP.
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Affiliation(s)
- Ana López-Saavedra
- Departamento de Genética, Universidad de Sevilla, 41080 Sevilla, Spain.,Department of Regenerative Medicine, Centro Andaluz de Biología Molecular y Medicina Regenerativa, 41092 Sevilla, Spain
| | - Daniel Gómez-Cabello
- Department of Regenerative Medicine, Centro Andaluz de Biología Molecular y Medicina Regenerativa, 41092 Sevilla, Spain
| | - María Salud Domínguez-Sánchez
- Department of Regenerative Medicine, Centro Andaluz de Biología Molecular y Medicina Regenerativa, 41092 Sevilla, Spain
| | - Fernando Mejías-Navarro
- Departamento de Genética, Universidad de Sevilla, 41080 Sevilla, Spain.,Department of Regenerative Medicine, Centro Andaluz de Biología Molecular y Medicina Regenerativa, 41092 Sevilla, Spain
| | - María Jesús Fernández-Ávila
- Department of Regenerative Medicine, Centro Andaluz de Biología Molecular y Medicina Regenerativa, 41092 Sevilla, Spain
| | - Christoffel Dinant
- Genome Integrity Unit, Danish Cancer Society Research Centre, Strandboulevarden 49, 2100 Copenhagen, Denmark
| | - María Isabel Martínez-Macías
- Departamento de Genética, Universidad de Sevilla, 41080 Sevilla, Spain.,Department of Regenerative Medicine, Centro Andaluz de Biología Molecular y Medicina Regenerativa, 41092 Sevilla, Spain
| | - Jiri Bartek
- Genome Integrity Unit, Danish Cancer Society Research Centre, Strandboulevarden 49, 2100 Copenhagen, Denmark.,Department of Medical Biochemistry and Biophysics, Science for Life Laboratory, Karolinska Institute, 171 76 Stockholm, Sweden
| | - Pablo Huertas
- Departamento de Genética, Universidad de Sevilla, 41080 Sevilla, Spain.,Department of Regenerative Medicine, Centro Andaluz de Biología Molecular y Medicina Regenerativa, 41092 Sevilla, Spain
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Abstract
Targeted drugs have changed cancer treatment but are often ineffective in the long term against solid tumours, largely because of the activation of heterogeneous oncogenic pathways. A central common signalling mechanism in many of these pathways is proline-directed phosphorylation, which is regulated by many kinases and phosphatases. The structure and function of these phosphorylated proteins are further controlled by a single proline isomerase: PIN1. PIN1 is overactivated in cancers and it promotes cancer and cancer stem cells by disrupting the balance of oncogenes and tumour suppressors. This Review discusses the roles of PIN1 in cancer and the potential of PIN1 inhibitors to restore this balance.
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Affiliation(s)
- Xiao Zhen Zhou
- Division of Translational Therapeutics, Department of Medicine and Cancer Research Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA
| | - Kun Ping Lu
- Division of Translational Therapeutics, Department of Medicine and Cancer Research Institute, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA
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43
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Paudyal SC, You Z. Sharpening the ends for repair: mechanisms and regulation of DNA resection. Acta Biochim Biophys Sin (Shanghai) 2016; 48:647-57. [PMID: 27174871 DOI: 10.1093/abbs/gmw043] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Accepted: 04/12/2016] [Indexed: 12/23/2022] Open
Abstract
DNA end resection is a key process in the cellular response to DNA double-strand break damage that is essential for genome maintenance and cell survival. Resection involves selective processing of 5' ends of broken DNA to generate ssDNA overhangs, which in turn control both DNA repair and checkpoint signaling. DNA resection is the first step in homologous recombination-mediated repair and a prerequisite for the activation of the ataxia telangiectasia mutated and Rad3-related (ATR)-dependent checkpoint that coordinates repair with cell cycle progression and other cellular processes. Resection occurs in a cell cycle-dependent manner and is regulated by multiple factors to ensure an optimal amount of ssDNA required for proper repair and genome stability. Here, we review the latest findings on the molecular mechanisms and regulation of the DNA end resection process and their implications for cancer formation and treatment.
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Affiliation(s)
- Sharad C Paudyal
- Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Zhongsheng You
- Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, MO 63110, USA
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44
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Agostoni E, Michelazzi S, Maurutto M, Carnemolla A, Ciani Y, Vatta P, Roncaglia P, Zucchelli S, Leanza G, Mantovani F, Gustincich S, Santoro C, Piazza S, Del Sal G, Persichetti F. Effects of Pin1 Loss in Hdh(Q111) Knock-in Mice. Front Cell Neurosci 2016; 10:110. [PMID: 27199664 PMCID: PMC4852193 DOI: 10.3389/fncel.2016.00110] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 04/18/2016] [Indexed: 01/21/2023] Open
Abstract
Huntington’s disease (HD) is a fatal, dominantly inherited, neurodegenerative disorder due to a pathological expansion of the CAG repeat in the coding region of the HTT gene. In the quest for understanding the molecular basis of neurodegeneration, we have previously demonstrated that the prolyl isomerase Pin1 plays a crucial role in mediating p53-dependent apoptosis triggered by mutant huntingtin (mHtt) in vitro. To assess the effects of the lack of Pin1 in vivo, we have bred Pin1 knock-out mice with HdhQ111 knock-in mice, a genetically precise model of HD. We show that Pin1 genetic ablation modifies a portion of HdhQ111 phenotypes in a time-dependent fashion. As an early event, Pin1 activity reduces the DNA damage response (DDR). In midlife mice, by taking advantage of next-generation sequencing technology, we show that Pin1 activity modulates a portion of the alterations triggered by mHtt, extending the role of Pin1 to two additional HdhQ111 phenotypes: the unbalance in the “synthesis/concentration of hormones”, as well as the alteration of “Wnt/β-catenin signaling”. In aging animals, Pin1 significantly increases the number of mHtt-positive nuclear inclusions while it reduces gliosis. In summary, this work provides further support for a role of Pin1 in HD pathogenesis.
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Affiliation(s)
- Elena Agostoni
- International School for Advanced Studies (SISSA), Area of Neuroscience Trieste, Italy
| | - Silvia Michelazzi
- International School for Advanced Studies (SISSA), Area of Neuroscience Trieste, Italy
| | - Marta Maurutto
- International School for Advanced Studies (SISSA), Area of Neuroscience Trieste, Italy
| | - Alisia Carnemolla
- International School for Advanced Studies (SISSA), Area of Neuroscience Trieste, Italy
| | - Yari Ciani
- Laboratorio Nazionale del Consorzio Interuniversitario per le Biotecnologie (LNCIB), Area Science ParkTrieste, Italy; Department of Life Sciences, University of TriesteTrieste, Italy
| | - Paolo Vatta
- International School for Advanced Studies (SISSA), Area of Neuroscience Trieste, Italy
| | - Paola Roncaglia
- International School for Advanced Studies (SISSA), Area of Neuroscience Trieste, Italy
| | - Silvia Zucchelli
- International School for Advanced Studies (SISSA), Area of NeuroscienceTrieste, Italy; Department of Health Sciences, University of Piemonte OrientaleNovara, Italy
| | - Giampiero Leanza
- Department of Life Sciences, University of Trieste Trieste, Italy
| | - Fiamma Mantovani
- Laboratorio Nazionale del Consorzio Interuniversitario per le Biotecnologie (LNCIB), Area Science ParkTrieste, Italy; Department of Life Sciences, University of TriesteTrieste, Italy
| | - Stefano Gustincich
- International School for Advanced Studies (SISSA), Area of NeuroscienceTrieste, Italy; Department of Neuroscience and Brain Technologies, Italian Institute of TechnologyGenova, Italy
| | - Claudio Santoro
- Department of Health Sciences, University of Piemonte Orientale Novara, Italy
| | - Silvano Piazza
- Laboratorio Nazionale del Consorzio Interuniversitario per le Biotecnologie (LNCIB), Area Science ParkTrieste, Italy; Department of Life Sciences, University of TriesteTrieste, Italy
| | - Giannino Del Sal
- Laboratorio Nazionale del Consorzio Interuniversitario per le Biotecnologie (LNCIB), Area Science ParkTrieste, Italy; Department of Life Sciences, University of TriesteTrieste, Italy
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45
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Saini P, Li Y, Dobbelstein M. Wee1 is required to sustain ATR/Chk1 signaling upon replicative stress. Oncotarget 2016; 6:13072-87. [PMID: 25965828 PMCID: PMC4537000 DOI: 10.18632/oncotarget.3865] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Accepted: 03/31/2015] [Indexed: 12/12/2022] Open
Abstract
The therapeutic efficacy of nucleoside analogues, e.g. gemcitabine, against cancer cells can be augmented by inhibitors of checkpoint kinases, including Wee1, ATR, and Chk1. We have compared the chemosensitizing effect of these inhibitors in cells derived from pancreatic cancer, a tumor entity where gemcitabine is part of the first-line therapeutic regimens, and in osteosarcoma-derived cells. As expected, all three inhibitors rendered cancer cells more sensitive to gemcitabine, but Wee1 inhibition proved to be particularly efficient in this context. Investigating the reasons for this potent sensitizing effect, we found that Wee1 inhibition or knockdown not only blocked Wee1 activity, but also reduced the activation of ATR/Chk1 in gemcitabine-treated cells. Combination of several inhibitors revealed that Wee1 inhibition requires Cyclin-dependent kinases 1 and 2 (Cdk1/2) and Polo-like kinase 1 (Plk1) to reduce ATR/Chk1 activity. Through activation of Cdks and Plk1, Wee1 inhibition reduces Claspin and CtIP levels, explaining the impairment in ATR/Chk1 activity. Taken together, these results confer a consistent signaling pathway reaching from Wee1 inhibition to impaired Chk1 activity, mechanistically dissecting how Wee1 inhibitors not only dysregulate cell cycle progression, but also enhance replicative stress and chemosensitivity towards nucleoside analogues.
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Affiliation(s)
- Priyanka Saini
- Institute of Molecular Oncology, Göttingen Centre of Molecular Biosciences (GZMB), Faculty of Medicine, University of Göttingen, Göttingen, Germany
| | - Yizhu Li
- Institute of Molecular Oncology, Göttingen Centre of Molecular Biosciences (GZMB), Faculty of Medicine, University of Göttingen, Göttingen, Germany
| | - Matthias Dobbelstein
- Institute of Molecular Oncology, Göttingen Centre of Molecular Biosciences (GZMB), Faculty of Medicine, University of Göttingen, Göttingen, Germany
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46
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Abstract
Both proteolytic and nonproteolytic functions of ubiquitination are essential regulatory mechanisms for promoting DNA repair and the DNA damage response in mammalian cells. Deubiquitinating enzymes (DUBs) have emerged as key players in the maintenance of genome stability. In this minireview, we discuss the recent findings on human DUBs that participate in genome maintenance, with a focus on the role of DUBs in the modulation of DNA repair and DNA damage signaling.
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47
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Hilton BA, Li Z, Musich PR, Wang H, Cartwright BM, Serrano M, Zhou XZ, Lu KP, Zou Y. ATR Plays a Direct Antiapoptotic Role at Mitochondria, which Is Regulated by Prolyl Isomerase Pin1. Mol Cell 2015; 60:35-46. [PMID: 26387736 DOI: 10.1016/j.molcel.2015.08.008] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Revised: 07/06/2015] [Accepted: 08/14/2015] [Indexed: 12/27/2022]
Abstract
ATR, a PI3K-like protein kinase, plays a key role in regulating DNA damage responses. Its nuclear checkpoint kinase function is well documented, but little is known about its function outside the nucleus. Here we report that ATR has an antiapoptotic activity at mitochondria in response to UV damage, and this activity is independent of its hallmark checkpoint/kinase activity and partner ATRIP. ATR contains a BH3-like domain that allows ATR-tBid interaction at mitochondria, suppressing cytochrome c release and apoptosis. This mitochondrial activity of ATR is downregulated by Pin1 that isomerizes ATR from cis-isomer to trans-isomer at the phosphorylated Ser428-Pro429 motif. However, UV inactivates Pin1 via DAPK1, stabilizing the pro-survival cis-isomeric ATR. In contrast, nuclear ATR remains in the trans-isoform disregarding UV. This cytoplasmic response of ATR may provide a mechanism for the observed antiapoptotic role of ATR in suppressing carcinogenesis and its inhibition in sensitizing anticancer agents for killing of cancer cells.
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Affiliation(s)
- Benjamin A Hilton
- Department of Biomedical Sciences, J.H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA
| | - Zhengke Li
- Department of Biomedical Sciences, J.H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA
| | - Phillip R Musich
- Department of Biomedical Sciences, J.H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA
| | - Hui Wang
- Department of Biomedical Sciences, J.H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA
| | - Brian M Cartwright
- Department of Biomedical Sciences, J.H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA
| | - Moises Serrano
- Department of Biomedical Sciences, J.H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA
| | - Xiao Zhen Zhou
- Department of Medicine, Center for Life Science, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Kun Ping Lu
- Department of Medicine, Center for Life Science, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Yue Zou
- Department of Biomedical Sciences, J.H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA.
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48
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Ma L, Milman N, Nambiar M, Smith GR. Two separable functions of Ctp1 in the early steps of meiotic DNA double-strand break repair. Nucleic Acids Res 2015; 43:7349-59. [PMID: 26130711 PMCID: PMC4551917 DOI: 10.1093/nar/gkv644] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 06/09/2015] [Indexed: 12/02/2022] Open
Abstract
Meiotic programmed DNA double-strand break (DSB) repair is essential for crossing-over and viable gamete formation and requires removal of Spo11-oligonucleotide complexes from 5′ ends (clipping) and their resection to generate invasive 3′-end single-stranded DNA (resection). Ctp1 (Com1, Sae2, CtIP homolog) acting with the Mre11-Rad50-Nbs1 (MRN) complex is required in both steps. We isolated multiple S. pombe ctp1 mutants deficient in clipping but proficient in resection during meiosis. Remarkably, all of the mutations clustered in or near the conserved CxxC or RHR motif in the C-terminal portion. The mutants tested, like ctp1Δ, were clipping-deficient by both genetic and physical assays. But, unlike ctp1Δ, these mutants were recombination-proficient for Rec12 (Spo11 homolog)-independent break-repair and resection-proficient by physical assay. We conclude that the intracellular Ctp1 C-terminal portion is essential for clipping, while the N-terminal portion is sufficient for DSB end-resection. This conclusion agrees with purified human CtIP resection and endonuclease activities being independent. Our mutants provide intracellular evidence for separable functions of Ctp1. Some mutations truncate Ctp1 in the same region as one of the CtIP mutations linked to the Seckel and Jawad severe developmental syndromes, suggesting that these syndromes are caused by a lack of clipping at DSB ends that require repair.
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Affiliation(s)
- Lijuan Ma
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Neta Milman
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Mridula Nambiar
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Gerald R Smith
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
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49
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Abstract
The mammalian CtIP protein and its orthologs in other eukaryotes promote the resection of DNA double-strand breaks and are essential for meiotic recombination. Here we review the current literature supporting the role of CtIP in DNA end processing and the importance of CtIP endonuclease activity in DNA repair. We also examine the regulation of CtIP function by post-translational modifications, and its involvement in transcription- and replication-dependent functions through association with other protein complexes. The tumor suppressor function of CtIP likely is dependent on a combination of these roles in many aspects of DNA metabolism.
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50
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Pin1: Intimate involvement with the regulatory protein kinase networks in the global phosphorylation landscape. Biochim Biophys Acta Gen Subj 2015; 1850:2077-86. [PMID: 25766872 DOI: 10.1016/j.bbagen.2015.02.018] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Revised: 02/25/2015] [Accepted: 02/27/2015] [Indexed: 02/06/2023]
Abstract
BACKGROUND Protein phosphorylation is a universal regulatory mechanism that involves an extensive network of protein kinases. The discovery of the phosphorylation-dependent peptidyl-prolyl isomerase Pin1 added an additional layer of complexity to these regulatory networks. SCOPE OF REVIEW We have evaluated interactions between Pin1 and the regulatory kinome and proline-dependent phosphoproteome taking into consideration findings from targeted studies as well as data that has emerged from systematic phosphoproteomic workflows and from curated protein interaction databases. MAJOR CONCLUSIONS The relationship between Pin1 and the regulatory protein kinase networks is not restricted simply to the recognition of proteins that are substrates for proline-directed kinases. In this respect, Pin1 itself is phosphorylated in cells by protein kinases that modulate its functional properties. Furthermore, the phosphorylation-dependent targets of Pin1 include a number of protein kinases as well as other enzymes such as phosphatases and regulatory subunits of kinases that modulate the actions of protein kinases. GENERAL SIGNIFICANCE As a result of its interactions with numerous protein kinases and their substrates, as well as itself being a target for phosphorylation, Pin1 has an intricate relationship with the regulatory protein kinase and phosphoproteomic networks that orchestrate complex cellular processes and respond to environmental cues. This article is part of a Special Issue entitled Proline-directed Foldases: Cell Signaling Catalysts and Drug Targets.
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