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Ikliptikawati DK, Makiyama K, Hazawa M, Wong RW. Unlocking the Gateway: The Spatio-Temporal Dynamics of the p53 Family Driven by the Nuclear Pores and Its Implication for the Therapeutic Approach in Cancer. Int J Mol Sci 2024; 25:7465. [PMID: 39000572 PMCID: PMC11242911 DOI: 10.3390/ijms25137465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2024] [Revised: 07/03/2024] [Accepted: 07/04/2024] [Indexed: 07/16/2024] Open
Abstract
The p53 family remains a captivating focus of an extensive number of current studies. Accumulating evidence indicates that p53 abnormalities rank among the most prevalent in cancer. Given the numerous existing studies, which mostly focus on the mutations, expression profiles, and functional perturbations exhibited by members of the p53 family across diverse malignancies, this review will concentrate more on less explored facets regarding p53 activation and stabilization by the nuclear pore complex (NPC) in cancer, drawing on several studies. p53 integrates a broad spectrum of signals and is subject to diverse regulatory mechanisms to enact the necessary cellular response. It is widely acknowledged that each stage of p53 regulation, from synthesis to degradation, significantly influences its functionality in executing specific tasks. Over recent decades, a large body of data has established that mechanisms of regulation, closely linked with protein activation and stabilization, involve intricate interactions with various cellular components. These often transcend canonical regulatory pathways. This new knowledge has expanded from the regulation of genes themselves to epigenomics and proteomics, whereby interaction partners increase in number and complexity compared with earlier paradigms. Specifically, studies have recently shown the involvement of the NPC protein in such complex interactions, underscoring the further complexity of p53 regulation. Furthermore, we also discuss therapeutic strategies based on recent developments in this field in combination with established targeted therapies.
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Affiliation(s)
- Dini Kurnia Ikliptikawati
- Cell-Bionomics Research Unit, Innovative Integrated Bio-Research Core, Institute for Frontier Science Initiative, Kanazawa University, Kakuma-machi, Kanazawa 9201192, Japan;
| | - Kei Makiyama
- Laboratory of Molecular Cell Biology, Division of Transdisciplinary Sciences, Graduate School of Frontier Science Initiative, Kanazawa University, Kakuma-machi, Kanazawa 9201192, Japan
| | - Masaharu Hazawa
- Cell-Bionomics Research Unit, Innovative Integrated Bio-Research Core, Institute for Frontier Science Initiative, Kanazawa University, Kakuma-machi, Kanazawa 9201192, Japan;
- Laboratory of Molecular Cell Biology, Division of Transdisciplinary Sciences, Graduate School of Frontier Science Initiative, Kanazawa University, Kakuma-machi, Kanazawa 9201192, Japan
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kakuma-machi, Kanazawa 9201192, Japan
| | - Richard W. Wong
- Cell-Bionomics Research Unit, Innovative Integrated Bio-Research Core, Institute for Frontier Science Initiative, Kanazawa University, Kakuma-machi, Kanazawa 9201192, Japan;
- Laboratory of Molecular Cell Biology, Division of Transdisciplinary Sciences, Graduate School of Frontier Science Initiative, Kanazawa University, Kakuma-machi, Kanazawa 9201192, Japan
- WPI Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kakuma-machi, Kanazawa 9201192, Japan
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2
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Liu T, Huang S, Zhang Q, Xia Y, Zhang M, Sun B. Reconciling ASPP-p53 binding mode discrepancies through an ensemble binding framework that bridges crystallography and NMR data. PLoS Comput Biol 2024; 20:e1011519. [PMID: 38324587 PMCID: PMC10878502 DOI: 10.1371/journal.pcbi.1011519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 02/20/2024] [Accepted: 01/24/2024] [Indexed: 02/09/2024] Open
Abstract
ASPP2 and iASPP bind to p53 through their conserved ANK-SH3 domains to respectively promote and inhibit p53-dependent cell apoptosis. While crystallography has indicated that these two proteins employ distinct surfaces of their ANK-SH3 domains to bind to p53, solution NMR data has suggested similar surfaces. In this study, we employed multi-scale molecular dynamics (MD) simulations combined with free energy calculations to reconcile the discrepancy in the binding modes. We demonstrated that the binding mode based solely on a single crystal structure does not enable iASPP's RT loop to engage with p53's C-terminal linker-a verified interaction. Instead, an ensemble of simulated iASPP-p53 complexes facilitates this interaction. We showed that the ensemble-average inter-protein contacting residues and NMR-detected interfacial residues qualitatively overlap on ASPP proteins, and the ensemble-average binding free energies better match experimental KD values compared to single crystallgarphy-determined binding mode. For iASPP, the sampled ensemble complexes can be grouped into two classes, resembling the binding modes determined by crystallography and solution NMR. We thus propose that crystal packing shifts the equilibrium of binding modes towards the crystallography-determined one. Lastly, we showed that the ensemble binding complexes are sensitive to p53's intrinsically disordered regions (IDRs), attesting to experimental observations that these IDRs contribute to biological functions. Our results provide a dynamic and ensemble perspective for scrutinizing these important cancer-related protein-protein interactions (PPIs).
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Affiliation(s)
- Te Liu
- Research Center for Pharmacoinformatics, College of Pharmacy, Harbin Medical University, Harbin, China
| | - Sichao Huang
- Research Center for Pharmacoinformatics, College of Pharmacy, Harbin Medical University, Harbin, China
| | - Qian Zhang
- Research Center for Pharmacoinformatics, College of Pharmacy, Harbin Medical University, Harbin, China
| | - Yu Xia
- Research Center for Pharmacoinformatics, College of Pharmacy, Harbin Medical University, Harbin, China
| | - Manjie Zhang
- Research Center for Pharmacoinformatics, College of Pharmacy, Harbin Medical University, Harbin, China
| | - Bin Sun
- Research Center for Pharmacoinformatics, College of Pharmacy, Harbin Medical University, Harbin, China
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3
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Al Moussawi K, Chung K, Carroll TM, Osterburg C, Smirnov A, Lotz R, Miller P, Dedeić Z, Zhong S, Oti M, Kouwenhoven EN, Asher R, Goldin R, Tellier M, Murphy S, Zhou H, Dötsch V, Lu X. Mutant Ras and inflammation-driven skin tumorigenesis is suppressed via a JNK-iASPP-AP1 axis. Cell Rep 2022; 41:111503. [PMID: 36261000 PMCID: PMC9597577 DOI: 10.1016/j.celrep.2022.111503] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Revised: 06/29/2022] [Accepted: 09/22/2022] [Indexed: 11/05/2022] Open
Abstract
Concurrent mutation of a RAS oncogene and the tumor suppressor p53 is common in tumorigenesis, and inflammation can promote RAS-driven tumorigenesis without the need to mutate p53. Here, we show, using a well-established mutant RAS and an inflammation-driven mouse skin tumor model, that loss of the p53 inhibitor iASPP facilitates tumorigenesis. Specifically, iASPP regulates expression of a subset of p63 and AP1 targets, including genes involved in skin differentiation and inflammation, suggesting that loss of iASPP in keratinocytes supports a tumor-promoting inflammatory microenvironment. Mechanistically, JNK-mediated phosphorylation regulates iASPP function and inhibits iASPP binding with AP1 components, such as JUND, via PXXP/SH3 domain-mediated interaction. Our results uncover a JNK-iASPP-AP1 regulatory axis that is crucial for tissue homeostasis. We show that iASPP is a tumor suppressor and an AP1 coregulator.
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Affiliation(s)
- Khatoun Al Moussawi
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
| | - Kathryn Chung
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
| | - Thomas M Carroll
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
| | - Christian Osterburg
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Frankfurt, Germany
| | - Artem Smirnov
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
| | - Rebecca Lotz
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Frankfurt, Germany
| | - Paul Miller
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
| | - Zinaida Dedeić
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
| | - Shan Zhong
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
| | - Martin Oti
- Radboud University, Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Nijmegen, the Netherlands
| | - Evelyn N Kouwenhoven
- Radboud University, Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Nijmegen, the Netherlands
| | - Ruth Asher
- Cellular Pathology, John Radcliffe Hospital, Oxford OX3 9DU, UK; Department of Histopathology, University Hospital Wales, Cardiff CF14 4XW, UK
| | - Robert Goldin
- Department of Pathology, Imperial College London, Faculty of Medicine at St Mary's, Norfolk Place, London W2 1PG, UK
| | - Michael Tellier
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Shona Murphy
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Huiqing Zhou
- Radboud University, Department of Molecular Developmental Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Nijmegen, the Netherlands; Radboud University Medical Centre, Department of Human Genetics, Radboud Institute for Molecular Life Sciences, 6500 Nijmegen, the Netherlands
| | - Volker Dötsch
- Institute of Biophysical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Frankfurt, Germany
| | - Xin Lu
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK.
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4
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Huo Y, Cao K, Kou B, Chai M, Dou S, Chen D, Shi Y, Liu X. TP53BP2: Roles in suppressing tumorigenesis and therapeutic opportunities. Genes Dis 2022. [PMID: 37492707 PMCID: PMC10363587 DOI: 10.1016/j.gendis.2022.08.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
Abstract
Malignant tumor is still a major problem worldwide. During tumorigenesis or tumor development, tumor suppressor p53-binding protein 2 (TP53BP2), also known as apoptosis stimulating protein 2 of p53 (ASPP2), plays a critical role in p53 dependent and independent manner. Expression of TP53BP2 is highly correlated with the prognosis and survival rate of malignant tumor patients. TP53BP2 can interact with p53, NF-κB p65, Bcl-2, HCV core protein, PP1, YAP, CagA, RAS, PAR3, and other proteins to regulate cell function. Moreover, TP53BP2 can also regulate the proliferation, apoptosis, autophagy, migration, EMT and drug resistance of tumor cells through downstream signaling pathways, such as NF-κB, RAS/MAPK, mevalonate, TGF-β1, PI3K/AKT, aPKC-ι/GLI1 and autophagy pathways. As a potential therapeutic target, TP53BP2 has been attracted more attention. We review the role of TP53BP2 in tumorigenesis or tumor development and the signal pathway involved in TP53BP2, which may provide more deep insight and strategies for tumor treatment.
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5
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Guven-Maiorov E, Sakakibara N, Ponnamperuma RM, Dong K, Matar H, King KE, Weinberg WC. Delineating functional mechanisms of the p53/p63/p73 family of transcription factors through identification of protein-protein interactions using interface mimicry. Mol Carcinog 2022; 61:629-642. [PMID: 35560453 PMCID: PMC9949960 DOI: 10.1002/mc.23405] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 01/27/2022] [Accepted: 01/31/2022] [Indexed: 11/08/2022]
Abstract
Members of the p53 family of transcription factors-p53, p63, and p73-share a high degree of homology; however, members can be activated in response to different stimuli, perform distinct (sometimes opposing) roles and are expressed in different tissues. The level of complexity is increased further by the transcription of multiple isoforms of each homolog, which may interact or interfere with each other and can impact cellular outcome. Proteins perform their functions through interacting with other proteins (and/or with nucleic acids). Therefore, identification of the interactors of a protein and how they interact in 3D is essential to fully comprehend their roles. By utilizing an in silico protein-protein interaction prediction method-HMI-PRED-we predicted interaction partners of p53 family members and modeled 3D structures of these protein interaction complexes. This method recovered experimentally known interactions while identifying many novel candidate partners. We analyzed the similarities and differences observed among the interaction partners to elucidate distinct functions of p53 family members and provide examples of how this information may yield mechanistic insight to explain their overlapping versus distinct/opposing outcomes in certain contexts. While some interaction partners are common to p53, p63, and p73, the majority are unique to each member. Nevertheless, most of the enriched pathways associated with these partners are common to all members, indicating that the members target the same biological pathways but through unique mediators. p63 and p73 have more common enriched pathways compared to p53, supporting their similar developmental roles in different tissues.
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Affiliation(s)
- Emine Guven-Maiorov
- Laboratory of Molecular Oncology, Office of Biotechnology Products, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD, United States.,National Cancer Institute, Bethesda, MD, United States.,Postal and email addresses of corresponding authors FDA/CDER/OPQ/OBP, Building 52-72/2306, 10903 New Hampshire Avenue, Silver Spring, MD 20993, United States, ,
| | - Nozomi Sakakibara
- Laboratory of Molecular Oncology, Office of Biotechnology Products, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD, United States
| | - Roshini M. Ponnamperuma
- Laboratory of Molecular Oncology, Office of Biotechnology Products, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD, United States
| | - Kun Dong
- Laboratory of Molecular Oncology, Office of Biotechnology Products, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD, United States.,National Cancer Institute, Bethesda, MD, United States
| | - Hector Matar
- Laboratory of Molecular Oncology, Office of Biotechnology Products, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD, United States
| | - Kathryn E. King
- Laboratory of Molecular Oncology, Office of Biotechnology Products, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD, United States
| | - Wendy C. Weinberg
- Laboratory of Molecular Oncology, Office of Biotechnology Products, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD, United States.,Postal and email addresses of corresponding authors FDA/CDER/OPQ/OBP, Building 52-72/2306, 10903 New Hampshire Avenue, Silver Spring, MD 20993, United States, ,
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6
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Mayer G, Shpilt Z, Kowalski H, Tshuva EY, Friedler A. Targeting Protein Interaction Hotspots Using Structured and Disordered Chimeric Peptide Inhibitors. ACS Chem Biol 2022; 17:1811-1823. [PMID: 35758642 DOI: 10.1021/acschembio.2c00177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The main challenge in inhibiting protein-protein interactions (PPI) for therapeutic purposes is designing molecules that bind specifically to the interaction hotspots. Adding to the complexity, such hotspots can be within both structured and disordered interaction interfaces. To address this, we present a strategy for inhibiting the structured and disordered hotspots of interactions using chimeric peptides that contain both structured and disordered parts. The chimeric peptides we developed are comprised of a cyclic structured part and a disordered part, which target both disordered and structured hotspots. We demonstrate our approach by developing peptide inhibitors for the interactions of the antiapoptotic iASPP protein. First, we developed a structured, α-helical stapled peptide inhibitor, derived from the N-terminal domain of MDM2. The peptide bound two hotspots on iASPP at the low micromolar range and had a cytotoxic effect on A2780 cancer cells with a half-maximal inhibitory concentration (IC50) value of 10 ± 1 μM. We then developed chimeric peptides comprising the structured stapled helical peptide and the disordered p53-derived LinkTer peptide that we previously showed to inhibit iASPP by targeting its disordered RT loop. The chimeric peptide targeted both structured and disordered domains in iASPP with higher affinity compared to the individual structured and disordered peptides and caused cancer cell death. Our strategy overcomes the inherent difficulty in inhibiting the interactions of proteins that possess structured and disordered regions. It does so by using chimeric peptides derived from different interaction partners that together target a much wider interface covering both the structured and disordered domains. This paves the way for developing such inhibitors for therapeutic purposes.
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Affiliation(s)
- Guy Mayer
- The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 9190401, Israel
| | - Zohar Shpilt
- The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 9190401, Israel
| | - Hadar Kowalski
- The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 9190401, Israel
| | - Edit Y Tshuva
- The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 9190401, Israel
| | - Assaf Friedler
- The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 9190401, Israel
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7
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Leissing TM, Hardy AP, Chan H, Wang Y, Tumber A, Chowdhury R, Feng T, Coleman ML, Cockman ME, Kramer HB, Berridge G, Fischer R, Kessler BM, Ratcliffe PJ, Lu X, Schofield CJ. Factor inhibiting HIF can catalyze two asparaginyl hydroxylations in VNVN motifs of ankyrin fold proteins. J Biol Chem 2022; 298:102020. [PMID: 35537551 PMCID: PMC9189129 DOI: 10.1016/j.jbc.2022.102020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 03/28/2022] [Accepted: 04/15/2022] [Indexed: 10/28/2022] Open
Abstract
The aspariginyl hydroxylase human factor inhibiting hypoxia-inducible factor (FIH) is an important regulator of the transcriptional activity of hypoxia-inducible factor. FIH also catalyzes the hydroxylation of asparaginyl and other residues in ankyrin repeat domain-containing proteins, including apoptosis stimulating of p53 protein (ASPP) family members. ASPP2 is reported to undergo a single FIH-catalyzed hydroxylation at Asn-986. We report biochemical and crystallographic evidence showing that FIH catalyzes the unprecedented post-translational hydroxylation of both asparaginyl residues in "VNVN" and related motifs of ankyrin repeat domains in ASPPs (i.e., ASPP1, ASPP2, and iASPP) and the related ASB11 and p18-INK4C proteins. Our biochemical results extend the substrate scope of FIH catalysis and may have implications for its biological roles, including in the hypoxic response and ASPP family function.
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Affiliation(s)
- Thomas M Leissing
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, United Kingdom; Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - Adam P Hardy
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, United Kingdom
| | - Hokfung Chan
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - Yihua Wang
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - Anthony Tumber
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, United Kingdom
| | - Rasheduzzaman Chowdhury
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, United Kingdom
| | - Tianshu Feng
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom; NDM Research Building, University of Oxford, Oxford, United Kingdom
| | - Mathew L Coleman
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Matthew E Cockman
- The Francis Crick Institute, Ratcliffe Laboratory, London, United Kingdom
| | - Holger B Kramer
- MRC London Institute of Medical Sciences, London, United Kingdom; Institute of Clinical Sciences, Imperial College London, Hammersmith Hospital Campus, London, United Kingdom
| | | | - Roman Fischer
- NDM Research Building, University of Oxford, Oxford, United Kingdom
| | | | - Peter J Ratcliffe
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom; The Francis Crick Institute, Ratcliffe Laboratory, London, United Kingdom.
| | - Xin Lu
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom.
| | - Christopher J Schofield
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, United Kingdom.
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8
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Mayer G, Shpilt Z, Bressler S, Marcu O, Schueler-Furman O, Tshuva EY, Friedler A. Targeting an Interaction Between Two Disordered Domains by Using a Designed Peptide. Chemistry 2020; 26:10240-10249. [PMID: 32181542 DOI: 10.1002/chem.202000465] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 03/14/2020] [Indexed: 11/09/2022]
Abstract
Intrinsically disordered regions in proteins (IDRs) mediate many disease-related protein-protein interactions. However, the unfolded character and continuous conformational changes of IDRs make them difficult to target for therapeutic purposes. Here, we show that a designed peptide based on the disordered p53 linker domain can be used to target a partner IDR from the anti-apoptotic iASPP protein, promoting apoptosis of cancer cells. The p53 linker forms a hairpin-like structure with its two termini in close proximity. We designed a peptide derived from the disordered termini without the hairpin, designated as p53 LinkTer. The LinkTer peptide binds the disordered RT loop of iASPP with the same affinity as the parent p53 linker peptide, and inhibits the p53-iASPP interaction in vitro. The LinkTer peptide shows increased stability to proteolysis, penetrates cancer cells, causes nuclei shrinkage, and compromises the viability of cells. We conclude that a designed peptide comprising only the IDR from a peptide sequence can serve as an improved inhibitor since it binds its target protein without the need for pre-folding, paving the way for therapeutic targeting of IDRs.
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Affiliation(s)
- Guy Mayer
- The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, Israel
| | - Zohar Shpilt
- The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, Israel
| | - Shachar Bressler
- The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, Israel
| | - Orly Marcu
- Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Ora Schueler-Furman
- Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Edit Y Tshuva
- The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, Israel
| | - Assaf Friedler
- The Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem, Israel
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9
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Chen S, Wu J, Zhong S, Li Y, Zhang P, Ma J, Ren J, Tan Y, Wang Y, Au KF, Siebold C, Bond GL, Chen Z, Lu M, Jones EY, Lu X. iASPP mediates p53 selectivity through a modular mechanism fine-tuning DNA recognition. Proc Natl Acad Sci U S A 2019; 116:17470-17479. [PMID: 31395738 PMCID: PMC6717262 DOI: 10.1073/pnas.1909393116] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The most frequently mutated protein in human cancer is p53, a transcription factor (TF) that regulates myriad genes instrumental in diverse cellular outcomes including growth arrest and cell death. Cell context-dependent p53 modulation is critical for this life-or-death balance, yet remains incompletely understood. Here we identify sequence signatures enriched in genomic p53-binding sites modulated by the transcription cofactor iASPP. Moreover, our p53-iASPP crystal structure reveals that iASPP displaces the p53 L1 loop-which mediates sequence-specific interactions with the signature-corresponding base-without perturbing other DNA-recognizing modules of the p53 DNA-binding domain. A TF commonly uses multiple structural modules to recognize its cognate DNA, and thus this mechanism of a cofactor fine-tuning TF-DNA interactions through targeting a particular module is likely widespread. Previously, all tumor suppressors and oncoproteins that associate with the p53 DNA-binding domain-except the oncogenic E6 from human papillomaviruses (HPVs)-structurally cluster at the DNA-binding site of p53, complicating drug design. By contrast, iASPP inhibits p53 through a distinct surface overlapping the E6 footprint, opening prospects for p53-targeting precision medicine to improve cancer therapy.
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Affiliation(s)
- Shuo Chen
- Ludwig Cancer Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - Jiale Wu
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Rui Jin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Shan Zhong
- Ludwig Cancer Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - Yuntong Li
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Rui Jin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Ping Zhang
- Ludwig Cancer Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - Jingyi Ma
- Ludwig Cancer Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - Jingshan Ren
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, United Kingdom
| | - Yun Tan
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Rui Jin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Yunhao Wang
- Department of Internal Medicine, University of Iowa, Iowa City, IA 52242
| | - Kin Fai Au
- Department of Internal Medicine, University of Iowa, Iowa City, IA 52242
- Department of Biostatistics, University of Iowa, Iowa City, IA 52242
| | - Christian Siebold
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, United Kingdom
| | - Gareth L Bond
- Ludwig Cancer Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
| | - Zhu Chen
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Rui Jin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China;
| | - Min Lu
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Rui Jin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China;
| | - E Yvonne Jones
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, United Kingdom;
| | - Xin Lu
- Ludwig Cancer Research, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom;
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10
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Zhou Y, Millott R, Kim HJ, Peng S, Edwards RA, Skene-Arnold T, Hammel M, Lees-Miller SP, Tainer JA, Holmes CFB, Glover JNM. Flexible Tethering of ASPP Proteins Facilitates PP-1c Catalysis. Structure 2019; 27:1485-1496.e4. [PMID: 31402222 DOI: 10.1016/j.str.2019.07.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 06/14/2019] [Accepted: 07/22/2019] [Indexed: 12/15/2022]
Abstract
ASPP (apoptosis-stimulating proteins of p53) proteins bind PP-1c (protein phosphatase 1) and regulate p53 impacting cancer cell growth and apoptosis. Here we determine the crystal structure of the oncogenic ASPP protein, iASPP, bound to PP-1c. The structure reveals a 1:1 complex that relies on interactions of the iASPP SILK and RVxF motifs with PP-1c, plus interactions of the PP-1c PxxPxR motif with the iASPP SH3 domain. Small-angle X-ray scattering analyses suggest that the crystal structure undergoes slow interconversion with more extended conformations in solution. We show that iASPP, and the tumor suppressor ASPP2, enhance the catalytic activity of PP-1c against the small-molecule substrate, pNPP as well as p53. The combined results suggest that PxxPxR binding to iASPP SH3 domain is critical for complex formation, and that the modular ASPP-PP-1c interface provides dynamic flexibility that enables functional binding and dephosphorylation of p53 and other diverse protein substrates.
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Affiliation(s)
- Yeyun Zhou
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Robyn Millott
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Hyeong Jin Kim
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Shiyun Peng
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Ross A Edwards
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Tamara Skene-Arnold
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Michal Hammel
- Molecular Biophysics & Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Susan P Lees-Miller
- Department of Biochemistry and Molecular Biology, Arnie Charbonneau Cancer Institute, University of Calgary, Calgary, AB, Canada
| | - John A Tainer
- Molecular Biophysics & Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Department of Molecular and Cellular Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Charles F B Holmes
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada.
| | - J N Mark Glover
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada.
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11
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Epigenetic Regulation of iASPP-p63 Feedback Loop in Cutaneous Squamous Cell Carcinoma. J Invest Dermatol 2019; 139:1658-1671.e8. [DOI: 10.1016/j.jid.2019.01.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 01/09/2019] [Accepted: 01/09/2019] [Indexed: 01/09/2023]
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12
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Poloni G, Calore M, Rigato I, Marras E, Minervini G, Mazzotti E, Lorenzon A, Li Mura IEA, Telatin A, Zara I, Simionati B, Perazzolo Marra M, Ponti J, Occhi G, Vitiello L, Daliento L, Thiene G, Basso C, Corrado D, Tosatto S, Bauce B, Rampazzo A, De Bortoli M. A targeted next-generation gene panel reveals a novel heterozygous nonsense variant in the TP63 gene in patients with arrhythmogenic cardiomyopathy. Heart Rhythm 2019; 16:773-780. [DOI: 10.1016/j.hrthm.2018.11.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Indexed: 12/14/2022]
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13
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Hafner A, Bulyk ML, Jambhekar A, Lahav G. The multiple mechanisms that regulate p53 activity and cell fate. Nat Rev Mol Cell Biol 2019; 20:199-210. [DOI: 10.1038/s41580-019-0110-x] [Citation(s) in RCA: 452] [Impact Index Per Article: 90.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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14
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Iosub-Amir A, Bai F, Sohn YS, Song L, Tamir S, Marjault HB, Mayer G, Karmi O, Jennings PA, Mittler R, Onuchic JN, Friedler A, Nechushtai R. The anti-apoptotic proteins NAF-1 and iASPP interact to drive apoptosis in cancer cells. Chem Sci 2018; 10:665-673. [PMID: 30774867 PMCID: PMC6349067 DOI: 10.1039/c8sc03390k] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 11/19/2018] [Indexed: 01/01/2023] Open
Abstract
We reveal a novel interaction between the two anti-apoptotic proteins iASPP and NAF-1, which are overexpressed in many types of cancer cells, and propose that this interaction is required for apoptosis activation in cancer cells. A peptide derived from the interaction interface inhibits apoptosis in cells.
Suppression of apoptosis is a key Hallmark of cancer cells, and reactivation of apoptosis is a major avenue for cancer therapy. We reveal an interaction between the two anti-apoptotic proteins iASPP and NAF-1, which are overexpressed in many types of cancer cells and tumors. iASPP is an inhibitory member of the ASPP protein family, whereas NAF-1 belongs to the NEET 2Fe–2S protein family. We show that the two proteins are stimulated to interact in cells during apoptosis. Using peptide array screening and computational methods we mapped the interaction interfaces of both proteins to residues 764–778 of iASPP that bind to a surface groove of NAF-1. A peptide corresponding to the iASPP 764–780 sequence stabilized the NAF-1 cluster, inhibited NAF-1 interaction with iASPP, and inhibited staurosporine-induced apoptosis activation in human breast cancer, as well as in PC-3 prostate cancer cells in which p53 is inactive. The iASPP 764–780 IC50 value for inhibition of cell death in breast cancer cells was 13 ± 1 μM. The level of cell death inhibition by iASPP 764–780 was altered in breast cancer cells expressing different levels and/or variants of NAF-1, indicating that the peptide activity is associated with NAF-1 function. We propose that the interaction between iASPP and NAF-1 is required for apoptosis activation in cancer cells. This interaction uncovers a new layer in the highly complex regulation of cell death in cancer cells and opens new avenues of exploration into the development of novel anticancer drugs that reactivate apoptosis in malignant tumors.
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Affiliation(s)
- Anat Iosub-Amir
- Institute of Chemistry , The Hebrew University of Jerusalem , Edmond J. Safra Campus at Givat Ram , Jerusalem 91904 , Israel .
| | - Fang Bai
- Center for Theoretical Biological Physics , Department of Physics , Rice University , Houston , TX 77005 , USA .
| | - Yang-Sung Sohn
- The Alexander Silberman Institute of Life Science , The Hebrew University of Jerusalem , Edmond J. Safra Campus at Givat Ram , Jerusalem 91904 , Israel .
| | - Luhua Song
- Department of Biological Sciences , University of North Texas , Denton , TX 76203 , USA
| | - Sagi Tamir
- The Alexander Silberman Institute of Life Science , The Hebrew University of Jerusalem , Edmond J. Safra Campus at Givat Ram , Jerusalem 91904 , Israel .
| | - Henri-Baptiste Marjault
- The Alexander Silberman Institute of Life Science , The Hebrew University of Jerusalem , Edmond J. Safra Campus at Givat Ram , Jerusalem 91904 , Israel .
| | - Guy Mayer
- Institute of Chemistry , The Hebrew University of Jerusalem , Edmond J. Safra Campus at Givat Ram , Jerusalem 91904 , Israel .
| | - Ola Karmi
- The Alexander Silberman Institute of Life Science , The Hebrew University of Jerusalem , Edmond J. Safra Campus at Givat Ram , Jerusalem 91904 , Israel .
| | - Patricia A Jennings
- Department of Chemistry & Biochemistry , University of California at San Diego , La Jolla , CA 92093 , USA
| | - Ron Mittler
- Department of Surgery , University of Missouri School of Medicine , Christopher S. Bond Life Sciences Center , University of Missouri , 1201 Rollins St , Columbia , MO 65201 , USA
| | - José N Onuchic
- Center for Theoretical Biological Physics , Department of Physics , Rice University , Houston , TX 77005 , USA .
| | - Assaf Friedler
- Institute of Chemistry , The Hebrew University of Jerusalem , Edmond J. Safra Campus at Givat Ram , Jerusalem 91904 , Israel .
| | - Rachel Nechushtai
- The Alexander Silberman Institute of Life Science , The Hebrew University of Jerusalem , Edmond J. Safra Campus at Givat Ram , Jerusalem 91904 , Israel .
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15
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Zou H, Zou R, Chen K, Zhu C, Tian X, You Y, He X. miR-129 targets CDK1 and iASPP to modulate Burkitt lymphoma cell proliferation in a TAp63-dependent manner. J Cell Biochem 2018; 119:9217-9228. [PMID: 30105797 DOI: 10.1002/jcb.27189] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 05/24/2018] [Indexed: 11/11/2022]
Abstract
Burkitt lymphoma is one of the most common lymphatic system cancers with poor outcome in adult patients. p53-induced apoptosis is a critical signaling for preventing tumor development. Cyclin B/cyclin-dependent kinase 1 (CDK1) phosphorylates inhibitor of apoptosis stimulating protein of P53 (iASPP) to promote iASPP nucleus localization and its inhibitory effect on p53. However, p53 is frequently mutated in Burkitt lymphoma, which gains novel oncogenic properties. Recently, the p53 family member, p63, became an attractive gene for the therapeutic strategies for patients with cancer. Therefore, we investigated the role of iASPP in the transactivation domain p63 (TAp63)-dependent cell proliferation inhibition in Burkitt lymphoma. We verified that the oncogenic effect of iASPP on Burkitt lymphoma is TAp63 dependent rather than p53 and confirmed that the interaction between CDK1 and iASPP enhanced the inhibitory effect of iASPP on p53 and TAp63. An online tool predicated that miR-129 might bind to 3'-untranslated region of iASPP and CDK1. We revealed that miR-129 acted as a tumor suppressor by inhibiting cancer cell proliferation and inhibiting CDK1 and iASPP via direct binding. An miR-129 inhibitor increased nucleus iASPP and decreased nucleus p53 and TAp63 levels, which could be reversed by the CDK1 knockdown, indicating that miR-129 might target CDK1 to inhibit iASPP phosphorylation, thus hindering iASPP nucleus localization and its inhibitory effect on p53 and TAp63 protein levels. Taken together, miR-129 could targetedly inhibit the expression of CDK1 and iASPP. CDK1 knockdown inhibits iASPP S84/S113 phosphorylation, thus blocking iASPP nucleus localization, suppressing the inhibitory effect of iASPP on p53 and TAp63, and restoring TAp63-induced proliferation inhibition in Burkitt lymphoma cells.
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Affiliation(s)
- Hui Zou
- Department of Hematology and Oncology of Children's Medical Center, The First Affiliated Hospital of Hunan Normal University/Hunan Provincial People's Hospital, Changsha, Hunan, China
| | - Runying Zou
- Department of Hematology and Oncology of Children's Medical Center, The First Affiliated Hospital of Hunan Normal University/Hunan Provincial People's Hospital, Changsha, Hunan, China
| | - Keke Chen
- Department of Hematology and Oncology of Children's Medical Center, The First Affiliated Hospital of Hunan Normal University/Hunan Provincial People's Hospital, Changsha, Hunan, China
| | - Chengguang Zhu
- Department of Hematology and Oncology of Children's Medical Center, The First Affiliated Hospital of Hunan Normal University/Hunan Provincial People's Hospital, Changsha, Hunan, China
| | - Xin Tian
- Department of Hematology and Oncology of Children's Medical Center, The First Affiliated Hospital of Hunan Normal University/Hunan Provincial People's Hospital, Changsha, Hunan, China
| | - Yalan You
- Department of Hematology and Oncology of Children's Medical Center, The First Affiliated Hospital of Hunan Normal University/Hunan Provincial People's Hospital, Changsha, Hunan, China
| | - Xiangling He
- Department of Hematology and Oncology of Children's Medical Center, The First Affiliated Hospital of Hunan Normal University/Hunan Provincial People's Hospital, Changsha, Hunan, China
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16
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Liu X, Wen S, Zhao S, Yan F, Zhao S, Wu D, Ji X. Mild Therapeutic Hypothermia Protects the Brain from Ischemia/Reperfusion Injury through Upregulation of iASPP. Aging Dis 2018; 9:401-411. [PMID: 29896428 PMCID: PMC5988595 DOI: 10.14336/ad.2017.0703] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 07/03/2017] [Indexed: 11/16/2022] Open
Abstract
Mild therapeutic hypothermia, a robust neuroprotectant, reduces neuronal apoptosis, but the precise mechanism is not well understood. Our previous study showed that a novel inhibitor of an apoptosis-stimulating protein of p53 (iASPP) might be involved in neuronal death after stroke. The aim of this study was to confirm the role of iASPP after stroke treated with mild therapeutic hypothermia. To address this, we mimicked ischemia/reperfusion injury in vitro by using oxygen-glucose deprivation/reperfusion (OGD/R) in primary rat neurons. In our in vivo approach, we induced middle cerebral artery occlusion (MCAO) for 60 min in C57/B6 mice. From the beginning of ischemia, focal mild hypothermia was applied for two hours. To evaluate the role of iASPP, small interfering RNA (siRNA) was injected intracerebroventricularly. Our results showed that mild therapeutic hypothermia increased the expression of iASPP and decreased the expression of its targets, Puma and Bax, and an apoptosis marker, cleaved caspase-3, in primary neurons under OGD/R. Increased iASPP expression and decreased ASPP1/2 expression were observed under hypothermia treatment in MCAO mice. iASPP siRNA (iASPPi) or hypothermia plus iASPPi application increased infarct volume, apoptosis and aggravated the neurological deficits in MCAO mice. Furthermore, iASPPi downregulated iASPP expression, and upregulated the expression of proapoptotic effectors, Puma, Bax and cleaved caspase-3, in mice after stroke treated with mild therapeutic hypothermia. In conclusion, mild therapeutic hypothermia protects against ischemia/reperfusion brain injury in mice by upregulating iASPP and thus attenuating apoptosis. iASPP may be a potential target in the therapy of stroke.
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Affiliation(s)
- Xiangrong Liu
- 1China-America Joint Institute of Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing, China.,2 Beijing Key Laboratory of Translational Medicine for Cerebrovascular Diseases, Beijing, China.,3Cerebrovascular Diseases Research Institute, Xuanwu Hospital of Capital Medical University, Beijing, China
| | - Shaohong Wen
- 1China-America Joint Institute of Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing, China.,2 Beijing Key Laboratory of Translational Medicine for Cerebrovascular Diseases, Beijing, China.,3Cerebrovascular Diseases Research Institute, Xuanwu Hospital of Capital Medical University, Beijing, China
| | - Shunying Zhao
- 1China-America Joint Institute of Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Feng Yan
- 2 Beijing Key Laboratory of Translational Medicine for Cerebrovascular Diseases, Beijing, China.,3Cerebrovascular Diseases Research Institute, Xuanwu Hospital of Capital Medical University, Beijing, China
| | - Shangfeng Zhao
- 4Department of Neurosurgery, Beijing Tongren Hospital, Capital University of Medical Sciences, Beijing, China
| | - Di Wu
- 1China-America Joint Institute of Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing, China.,2 Beijing Key Laboratory of Translational Medicine for Cerebrovascular Diseases, Beijing, China
| | - Xunming Ji
- 1China-America Joint Institute of Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing, China.,2 Beijing Key Laboratory of Translational Medicine for Cerebrovascular Diseases, Beijing, China.,3Cerebrovascular Diseases Research Institute, Xuanwu Hospital of Capital Medical University, Beijing, China.,5Department of Neurosurgery, Xuanwu Hospital of Capital Medical University, Beijing, China
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17
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iASPP facilitates tumor growth by promoting mTOR-dependent autophagy in human non-small-cell lung cancer. Cell Death Dis 2017; 8:e3150. [PMID: 29072696 PMCID: PMC5682680 DOI: 10.1038/cddis.2017.515] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 08/10/2017] [Accepted: 08/17/2017] [Indexed: 12/27/2022]
Abstract
Autophagy serves a critical function in the pathogenesis, response to therapy and clinical outcome in cancers. Although a recent report showed a role of iASPP in suppressing autophagy, its potential activity as a regulator of autophagy has not been investigated in lung cancer. Here we investigated the potential function and molecular mechanism of iASPP in mediating autophagy in human non-small-cell lung cancer. Our data suggested that forced expression of iASPP triggered autophagic flux, while inhibition of iASPP suppressed autophagy at the autophagsome formation stage in vitro. Furthermore, in vivo overexpression of iASPP in SCID/NOD mice promoted tumorigenesis and autophagy, with an increase in the conversion from LC3-I to LC3-II. The effects of iASPP were mediated through activation of mTOR pathway. Finally, cytoplasmic iASPP expression was upregulated in lung cancer patients, and was identified as an independent poor prognostic factor for lung cancer-specific death in patient samples. Taken together, our data showed that iASPP could promote tumor growth by increasing autophagic flux, and iASPP could serve as a poor prognostic factor and a potential therapeutic target in lung cancer.
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18
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Wang X, Cheng Y, Zhu Y, Li H, Ge W, Wu X, Zhao K, Yuan J, Li Z, Jiang S, Han Z, Jiang Q, Wu Q, Liu T, Zhang C, Yu M, Hu Y. Epigenetic silencing of ASPP1 confers 5‐FU resistance in clear cell renal cell carcinoma by preventing p53 activation. Int J Cancer 2017; 141:1422-1433. [DOI: 10.1002/ijc.30852] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 05/07/2017] [Accepted: 06/21/2017] [Indexed: 12/11/2022]
Affiliation(s)
- Xingwen Wang
- School of Life Science and TechnologyHarbin Institute of TechnologyHarbin Heilongjiang150001 China
- Shenzhen Graduate School of Harbin Institute of TechnologyXili University CityNanshanShenzhen Guangdong518055 China
| | - Yiwei Cheng
- The First Affiliated HospitalHarbin Medical UniversityHarbin Heilongjiang150081 China
| | - YiFu Zhu
- School of Life Science and TechnologyHarbin Institute of TechnologyHarbin Heilongjiang150001 China
| | - Huayi Li
- School of Life Science and TechnologyHarbin Institute of TechnologyHarbin Heilongjiang150001 China
| | - Wenjie Ge
- School of Life Science and TechnologyHarbin Institute of TechnologyHarbin Heilongjiang150001 China
- Shenzhen Graduate School of Harbin Institute of TechnologyXili University CityNanshanShenzhen Guangdong518055 China
| | - Xiaoliang Wu
- School of Life Science and TechnologyHarbin Institute of TechnologyHarbin Heilongjiang150001 China
| | - Kunming Zhao
- School of Life Science and TechnologyHarbin Institute of TechnologyHarbin Heilongjiang150001 China
| | - Jinyang Yuan
- The First Affiliated HospitalHarbin Medical UniversityHarbin Heilongjiang150081 China
| | - Zhenglin Li
- School of Chemical Engineering and TechnologyHarbin Institute of TechnologyHarbin Heilongjiang150001 China
| | - Shijian Jiang
- School of Life Science and TechnologyHarbin Institute of TechnologyHarbin Heilongjiang150001 China
| | - Zhengbin Han
- School of Life Science and TechnologyHarbin Institute of TechnologyHarbin Heilongjiang150001 China
| | - Qinghua Jiang
- School of Life Science and TechnologyHarbin Institute of TechnologyHarbin Heilongjiang150001 China
| | - Qiong Wu
- School of Life Science and TechnologyHarbin Institute of TechnologyHarbin Heilongjiang150001 China
| | - Tao Liu
- Shenzhen Luohu People's Hospital, Shenzhen Zhongxun Precision Medicine Research InstituteShenzhen Guangdong518001 China
| | - Cheng Zhang
- The First Affiliated HospitalHarbin Medical UniversityHarbin Heilongjiang150081 China
| | - Miao Yu
- School of Chemical Engineering and TechnologyHarbin Institute of TechnologyHarbin Heilongjiang150001 China
| | - Ying Hu
- School of Life Science and TechnologyHarbin Institute of TechnologyHarbin Heilongjiang150001 China
- Shenzhen Graduate School of Harbin Institute of TechnologyXili University CityNanshanShenzhen Guangdong518055 China
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19
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Lambrughi M, De Gioia L, Gervasio FL, Lindorff-Larsen K, Nussinov R, Urani C, Bruschi M, Papaleo E. DNA-binding protects p53 from interactions with cofactors involved in transcription-independent functions. Nucleic Acids Res 2016; 44:9096-9109. [PMID: 27604871 PMCID: PMC5100575 DOI: 10.1093/nar/gkw770] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 08/19/2016] [Accepted: 08/23/2016] [Indexed: 12/15/2022] Open
Abstract
Binding-induced conformational changes of a protein at regions distant from the binding site may play crucial roles in protein function and regulation. The p53 tumour suppressor is an example of such an allosterically regulated protein. Little is known, however, about how DNA binding can affect distal sites for transcription factors. Furthermore, the molecular details of how a local perturbation is transmitted through a protein structure are generally elusive and occur on timescales hard to explore by simulations. Thus, we employed state-of-the-art enhanced sampling atomistic simulations to unveil DNA-induced effects on p53 structure and dynamics that modulate the recruitment of cofactors and the impact of phosphorylation at Ser215. We show that DNA interaction promotes a conformational change in a region 3 nm away from the DNA binding site. Specifically, binding to DNA increases the population of an occluded minor state at this distal site by more than 4-fold, whereas phosphorylation traps the protein in its major state. In the minor conformation, the interface of p53 that binds biological partners related to p53 transcription-independent functions is not accessible. Significantly, our study reveals a mechanism of DNA-mediated protection of p53 from interactions with partners involved in the p53 transcription-independent signalling. This also suggests that conformational dynamics is tightly related to p53 signalling.
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Affiliation(s)
- Matteo Lambrughi
- Computational Biology Laboratory, Unit of Statistics, Bioinformatics and Registry, Strandboulevarden 49, 2100, Copenhagen, Denmark
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Luca De Gioia
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126, Milan, Italy
| | - Francesco Luigi Gervasio
- Department of Chemistry and Institute of Structural and Molecular Biology, University College London, London WC1H 0AJ, UK
| | - Kresten Lindorff-Larsen
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Ruth Nussinov
- Cancer and Inflammation Program, Leidos Biomedical Research Inc., Frederick National laboratory, National Cancer Institute, Frederick, MD 21702, USA
- Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Chiara Urani
- Department of Earth and Environmental Sciences, University of Milano-Bicocca, Piazza della Scienza 1, 20126, Milan, Italy
| | - Maurizio Bruschi
- Department of Earth and Environmental Sciences, University of Milano-Bicocca, Piazza della Scienza 1, 20126, Milan, Italy
| | - Elena Papaleo
- Computational Biology Laboratory, Unit of Statistics, Bioinformatics and Registry, Strandboulevarden 49, 2100, Copenhagen, Denmark
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Copenhagen, Denmark
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20
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Joerger AC, Fersht AR. The p53 Pathway: Origins, Inactivation in Cancer, and Emerging Therapeutic Approaches. Annu Rev Biochem 2016; 85:375-404. [DOI: 10.1146/annurev-biochem-060815-014710] [Citation(s) in RCA: 363] [Impact Index Per Article: 45.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Andreas C. Joerger
- Medical Research Council Laboratory of Molecular Biology, Cambridge CB2 0QH, United Kingdom
- German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
- Institute of Pharmaceutical Chemistry, Johann Wolfgang Goethe University, 60438 Frankfurt am Main, Germany;
| | - Alan R. Fersht
- Medical Research Council Laboratory of Molecular Biology, Cambridge CB2 0QH, United Kingdom
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21
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Highly homologous proteins exert opposite biological activities by using different interaction interfaces. Sci Rep 2015; 5:11629. [PMID: 26130271 PMCID: PMC4486954 DOI: 10.1038/srep11629] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 06/02/2015] [Indexed: 11/08/2022] Open
Abstract
We present a possible molecular basis for the opposite activity of two homologues proteins that bind similar ligands and show that this is achieved by fine-tuning of the interaction interface. The highly homologous ASPP proteins have opposite roles in regulating apoptosis: ASPP2 induces apoptosis while iASPP inhibits it. The ASPP proteins are regulated by an autoinhibitory interaction between their Ank-SH3 and Pro domains. We performed a detailed biophysical and molecular study of the Pro - Ank-SH3 interaction in iASPP and compared it to the interaction in ASPP2. We found that iASPP Pro is disordered and that the interaction sites are entirely different: iASPP Ank-SH3 binds iASPP Pro via its fourth Ank repeat and RT loop while ASPP2 Ank-SH3 binds ASPP2 Pro via its first Ank repeat and the n-src loop. It is possible that by using different moieties in the same interface, the proteins can have distinct and specific interactions resulting in differential regulation and ultimately different biological activities.
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22
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Reingewertz TH, Iosub-Amir A, Bonsor DA, Mayer G, Amartely H, Friedler A, Sundberg EJ. An Intrinsically Disordered Region in the Proapoptotic ASPP2 Protein Binds to the Helicobacter pylori Oncoprotein CagA. Biochemistry 2015; 54:3337-47. [PMID: 25963096 DOI: 10.1021/acs.biochem.5b00084] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The leading risk factor for gastric cancer in humans is infection by Helicobacter pylori strains that express and translocate the oncoprotein CagA into host epithelial cells. Once inside host cells, CagA interacts with ASPP2, which specifically stimulates p53-mediated apoptosis and reverses its pro-apoptotic function to promote ASPP2-dependent degradation of p53. The X-ray crystal structure of a complex between the N-terminal domain of CagA and a 56-residue fragment of ASPP2, of which 22 residues were resolved, was recently described. Here, we present biochemical and biophysical analyses of the interaction between the additional regions of CagA and ASPP2 potentially involved in this interaction. Using size exclusion chromatography-multiangle laser light scattering, circular dichroism, and nuclear magnetic resonance analyses, we observed that the ASPP2 region spanning residues 331-692, which was not part of the ASPP2 fragment used for crystallization, is intrinsically disordered in its unbound state. By surface plasmon resonance analysis and isothermal titration calorimetry, we found that a portion of this disordered region in ASPP2, residues 448-692, binds to the N-terminal domain of CagA. We also measured the affinity of the complex between the ASPP2 fragment composed of residues 693-918 and inclusive of the fragment used for crystallization and CagA. Additionally, we mapped the binding regions between ASPP2 and CagA using peptide arrays, demonstrating interactions between CagA and numerous peptides distributed throughout the ASPP2 protein sequence. Our results identify previously uncharacterized regions distributed throughout the protein sequence of ASPP2 as determinants of CagA binding, providing mechanistic insight into apoptosis reprogramming by CagA and potential new drug targets for H. pylori-mediated gastric cancer.
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Affiliation(s)
| | - Anat Iosub-Amir
- ‡Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | | | - Guy Mayer
- ‡Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Hadar Amartely
- ‡Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Assaf Friedler
- ‡Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
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Kramer D, Schön M, Bayerlová M, Bleckmann A, Schön MP, Zörnig M, Dobbelstein M. A pro-apoptotic function of iASPP by stabilizing p300 and CBP through inhibition of BRMS1 E3 ubiquitin ligase activity. Cell Death Dis 2015; 6:e1634. [PMID: 25675294 PMCID: PMC4669821 DOI: 10.1038/cddis.2015.17] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 12/27/2014] [Accepted: 01/02/2015] [Indexed: 12/26/2022]
Abstract
The p53 family and its cofactors are potent inducers of apoptosis and form a barrier to cancer. Here, we investigated the impact of the supposedly inhibitory member of the apoptosis-stimulating protein of p53, iASPP, on the activity of the p53 homolog TAp73, and its cofactors p300 and CBP. We found that iASPP interacted with and stabilized the histone acetyltransferase p300 and its homolog CBP upon cisplatin treatment. Vice versa, iASPP depletion by shRNA resulted in decreased amounts of p300 and CBP, impaired binding of p300 and TAp73 to target site promoters, reduced induction of pro-apoptotic TAp73 target genes, and impaired apoptosis. Mechanistically, we observed that the p300-regulatory E3 ubiquitin ligase BRMS1 could rescue the degradation of p300 and CBP in cisplatin-treated, iASPP-depleted cells. This argues that iASPP stabilizes p300 and CBP by interfering with their BRMS1-mediated ubiquitination, thereby contributing to apoptotic susceptibility. In line, iASPP overexpression partially abolished the interaction of BRMS1 and CBP upon DNA damage. Reduced levels of iASPP mRNA and protein as well as CBP protein were observed in human melanoma compared with normal skin tissue and benign melanocytic nevi. In line with our findings, iASPP overexpression or knockdown of BRMS1 each augmented p300/CBP levels in melanoma cell lines, thereby enhancing apoptosis upon DNA damage. Taken together, destabilization of p300/CBP by downregulation of iASPP expression levels appears to represent a molecular mechanism that contributes to chemoresistance in melanoma cells.
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Affiliation(s)
- D Kramer
- Department of Molecular Oncology, University Medical Center Göttingen, Göttingen, Germany
| | - M Schön
- Department of Dermatology, Venereology and Allergology, University Medical Center Göttingen, Göttingen, Germany
| | - M Bayerlová
- Department of Medical Statistics, University Medical Center Göttingen, Göttingen, Germany
| | - A Bleckmann
- Department of Hematology and Medical Oncology, University Medical Center Göttingen, Göttingen, Germany
| | - M P Schön
- Department of Dermatology, Venereology and Allergology, University Medical Center Göttingen, Göttingen, Germany
| | - M Zörnig
- Institute of Tumor Biology and Experimental Therapy, Georg Speyer Haus, Frankfurt am Main,Germany
| | - M Dobbelstein
- Department of Molecular Oncology, University Medical Center Göttingen, Göttingen, Germany
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24
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Yoh K, Prywes R. Pathway Regulation of p63, a Director of Epithelial Cell Fate. Front Endocrinol (Lausanne) 2015; 6:51. [PMID: 25972840 PMCID: PMC4412127 DOI: 10.3389/fendo.2015.00051] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 04/02/2015] [Indexed: 02/03/2023] Open
Abstract
The p53-related gene p63 is required for epithelial cell establishment and its expression is often altered in tumor cells. Great strides have been made in understanding the pathways and mechanisms that regulate p63 levels, such as the Wnt, Hedgehog, Notch, and EGFR pathways. We discuss here the multiple signaling pathways that control p63 expression as well as transcription factors and post-transcriptional mechanisms that regulate p63 levels. While a unified picture has not emerged, it is clear that the fine-tuning of p63 has evolved to carefully control epithelial cell differentiation and fate.
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Affiliation(s)
- Kathryn Yoh
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Ron Prywes
- Department of Biological Sciences, Columbia University, New York, NY, USA
- *Correspondence: Ron Prywes, Department of Biological Sciences, Columbia University, Fairchild 813A, MC2420, 1212 Amsterdam Avenue, New York, NY 10027, USA,
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25
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Chen Y, Yan W, He S, Chen J, Chen D, Zhang Z, Liu Z, Ding X, Wang A. In vitro effect of iASPP on cell growth of oral tongue squamous cell carcinoma. Chin J Cancer Res 2014; 26:382-90. [PMID: 25232209 DOI: 10.3978/j.issn.1000-9604.2014.07.05] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2014] [Accepted: 07/24/2014] [Indexed: 01/28/2023] Open
Abstract
iASPP is an inhibitory member of the apoptosis-stimulating proteins of P53 (ASPP) family. iASPP is over expressed in several malignant tumors and potentially affects cancer progression. However, the expression and potential role of iASPP in oral tongue squamous cell carcinoma (OTSCC) have not been addressed. In our study, we detected iASPP expression in OTSCC by immunohistochemistry. iASPP expression is up-regulated in OTSCC tissues. Moreover, in clinical pathology specimens, we found that increased iASPP expression correlates with poor differentiation and lymph node metastasis. Using multicellular tumor spheroids (MTS) and flow cytometry, we demonstrated that iASPP down-regulation arrests OTSCC cells at the G0/G1 phase, induces OTSCC cell apoptosis and inhibits OTSCC cell proliferation. These results indicate that iASPP plays a significant role in the progression of OTSCC and may serve as a biomarker or therapeutic target for OTSCC patients.
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Affiliation(s)
- Yu Chen
- 1 Department of Oral & Maxillofacial Surgery, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China, 2 Department of Stomatology, First Affiliated Hospital of Jinan University, Guangzhou 510630, China ; 3 Operation Room, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China ; 4 Department of Stomatology, Sixth Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510655, China
| | - Wangxiang Yan
- 1 Department of Oral & Maxillofacial Surgery, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China, 2 Department of Stomatology, First Affiliated Hospital of Jinan University, Guangzhou 510630, China ; 3 Operation Room, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China ; 4 Department of Stomatology, Sixth Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510655, China
| | - Shuqi He
- 1 Department of Oral & Maxillofacial Surgery, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China, 2 Department of Stomatology, First Affiliated Hospital of Jinan University, Guangzhou 510630, China ; 3 Operation Room, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China ; 4 Department of Stomatology, Sixth Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510655, China
| | - Jiechun Chen
- 1 Department of Oral & Maxillofacial Surgery, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China, 2 Department of Stomatology, First Affiliated Hospital of Jinan University, Guangzhou 510630, China ; 3 Operation Room, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China ; 4 Department of Stomatology, Sixth Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510655, China
| | - Dan Chen
- 1 Department of Oral & Maxillofacial Surgery, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China, 2 Department of Stomatology, First Affiliated Hospital of Jinan University, Guangzhou 510630, China ; 3 Operation Room, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China ; 4 Department of Stomatology, Sixth Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510655, China
| | - Zhaoqiang Zhang
- 1 Department of Oral & Maxillofacial Surgery, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China, 2 Department of Stomatology, First Affiliated Hospital of Jinan University, Guangzhou 510630, China ; 3 Operation Room, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China ; 4 Department of Stomatology, Sixth Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510655, China
| | - Zhiguo Liu
- 1 Department of Oral & Maxillofacial Surgery, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China, 2 Department of Stomatology, First Affiliated Hospital of Jinan University, Guangzhou 510630, China ; 3 Operation Room, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China ; 4 Department of Stomatology, Sixth Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510655, China
| | - Xueqiang Ding
- 1 Department of Oral & Maxillofacial Surgery, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China, 2 Department of Stomatology, First Affiliated Hospital of Jinan University, Guangzhou 510630, China ; 3 Operation Room, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China ; 4 Department of Stomatology, Sixth Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510655, China
| | - Anxun Wang
- 1 Department of Oral & Maxillofacial Surgery, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China, 2 Department of Stomatology, First Affiliated Hospital of Jinan University, Guangzhou 510630, China ; 3 Operation Room, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China ; 4 Department of Stomatology, Sixth Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510655, China
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Costanzo A, Pediconi N, Narcisi A, Guerrieri F, Belloni L, Fausti F, Botti E, Levrero M. TP63 and TP73 in cancer, an unresolved "family" puzzle of complexity, redundancy and hierarchy. FEBS Lett 2014; 588:2590-9. [PMID: 24983500 DOI: 10.1016/j.febslet.2014.06.047] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 06/16/2014] [Accepted: 06/16/2014] [Indexed: 12/24/2022]
Abstract
TP53 belongs to a small gene family that includes, in mammals, two additional paralogs, TP63 and TP73. The p63 and p73 proteins are structurally and functionally similar to p53 and their activity as transcription factors is regulated by a wide repertoire of shared and unique post-translational modifications and interactions with regulatory cofactors. p63 and p73 have important functions in embryonic development and differentiation but are also involved in tumor suppression. The biology of p63 and p73 is complex since both TP63 and TP73 genes are transcribed into a variety of different isoforms that give rise to proteins with antagonistic properties, the TA-isoforms that act as tumor-suppressors and DN-isoforms that behave as proto-oncogenes. The p53 family as a whole behaves as a signaling "network" that integrates developmental, metabolic and stress signals to control cell metabolism, differentiation, longevity, proliferation and death. Despite the progress of our knowledge, the unresolved puzzle of complexity, redundancy and hierarchy in the p53 family continues to represent a formidable challenge.
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Affiliation(s)
- Antonio Costanzo
- Dermatology Unit, Department of Neuroscience, Mental Health and Sensory Organs (NESMOS), Sapienza University of Rome, Italy
| | - Natalia Pediconi
- Laboratory of Molecular Oncology, Department of Molecular Medicine, Sapienza University of Rome, Italy; Center for Life Nanosciences (CNLS) - IIT/Sapienza, Rome, Italy
| | - Alessandra Narcisi
- Dermatology Unit, Department of Neuroscience, Mental Health and Sensory Organs (NESMOS), Sapienza University of Rome, Italy
| | - Francesca Guerrieri
- Center for Life Nanosciences (CNLS) - IIT/Sapienza, Rome, Italy; Laboratory of Gene Expression, Department of Internal Medicine (DMISM), Sapienza University of Rome, Italy
| | - Laura Belloni
- Center for Life Nanosciences (CNLS) - IIT/Sapienza, Rome, Italy; Laboratory of Gene Expression, Department of Internal Medicine (DMISM), Sapienza University of Rome, Italy
| | - Francesca Fausti
- Dermatology Unit, Department of Neuroscience, Mental Health and Sensory Organs (NESMOS), Sapienza University of Rome, Italy
| | - Elisabetta Botti
- Dermatology Unit, Department of Neuroscience, Mental Health and Sensory Organs (NESMOS), Sapienza University of Rome, Italy
| | - Massimo Levrero
- Center for Life Nanosciences (CNLS) - IIT/Sapienza, Rome, Italy; Laboratory of Gene Expression, Department of Internal Medicine (DMISM), Sapienza University of Rome, Italy.
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27
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Iosub-Amir A, Friedler A. Protein–protein interactions of ASPP2: an emerging therapeutic target. MEDCHEMCOMM 2014. [DOI: 10.1039/c4md00147h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
ASPP2 induces apoptosis and is downregulated in many types of cancer, making it a promising target for anti-cancer drugs.
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Affiliation(s)
- Anat Iosub-Amir
- Institute of Chemistry
- The Hebrew University of Jerusalem
- Safra Campus
- Jerusalem 91904, Israel
| | - Assaf Friedler
- Institute of Chemistry
- The Hebrew University of Jerusalem
- Safra Campus
- Jerusalem 91904, Israel
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28
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Schittenhelm MM, Illing B, Ahmut F, Rasp KH, Blumenstock G, Döhner K, Lopez CD, Kampa-Schittenhelm KM. Attenuated expression of apoptosis stimulating protein of p53-2 (ASPP2) in human acute leukemia is associated with therapy failure. PLoS One 2013; 8:e80193. [PMID: 24312201 PMCID: PMC3842400 DOI: 10.1371/journal.pone.0080193] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Accepted: 09/10/2013] [Indexed: 12/31/2022] Open
Abstract
Inactivation of the p53 pathway is a universal event in human cancers and promotes tumorigenesis and resistance to chemotherapy. Inactivating p53 mutations are uncommon in non-complex karyotype leukemias, thus the p53-pathway must be inactivated by other mechanisms. The Apoptosis Stimulating Protein of p53-2 (ASPP2) is a damage-inducible p53-binding protein that enhances apoptosis at least in part through a p53-mediated pathway. We have previously shown, that ASPP2 is an independent haploinsufficient tumor suppressor in vivo. Now, we reveal that ASPP2 expression is significantly attenuated in acute myeloid and lymphoid leukemia – especially in patients with an unfavorable prognostic risk profile and patients who fail induction chemotherapy. In line, knock down of ASPP2 in expressing leukemia cell lines and native leukemic blasts attenuates damage-induced apoptosis. Furthermore, cultured blasts derived from high-risk leukemias fail to induce ASPP2 expression upon anthracycline treatment. The mechanisms of ASPP2 dysregulation are unknown. We provide evidence that attenuation of ASPP2 is caused by hypermethylation of the promoter and 5′UTR regions in native leukemia blasts. Together, our results suggest that ASPP2 contributes to the biology of leukemia and expression should be further explored as a potential prognostic and/or predictive biomarker to monitor therapy responses in acute leukemia.
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MESH Headings
- Adult
- Aged
- Antineoplastic Agents/pharmacology
- Antineoplastic Agents/therapeutic use
- Apoptosis/drug effects
- Apoptosis/genetics
- Apoptosis Regulatory Proteins/genetics
- Apoptosis Regulatory Proteins/metabolism
- Cell Line, Tumor
- Female
- Gene Expression Regulation, Leukemic
- Gene Knockdown Techniques
- Humans
- Leukemia, Myeloid, Acute/drug therapy
- Leukemia, Myeloid, Acute/genetics
- Leukemia, Myeloid, Acute/pathology
- Male
- Middle Aged
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Treatment Failure
- Treatment Outcome
- Young Adult
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Affiliation(s)
- Marcus M. Schittenhelm
- University Hospital Tübingen, Department of Hematology, Oncology, Rheumatology, Immunology and Pulmology, Tübingen, Germany
| | - Barbara Illing
- University Hospital Tübingen, Department of Hematology, Oncology, Rheumatology, Immunology and Pulmology, Tübingen, Germany
| | - Figen Ahmut
- University Hospital Tübingen, Department of Hematology, Oncology, Rheumatology, Immunology and Pulmology, Tübingen, Germany
| | - Katharina Henriette Rasp
- University Hospital Tübingen, Department of Hematology, Oncology, Rheumatology, Immunology and Pulmology, Tübingen, Germany
| | - Gunnar Blumenstock
- Department of Clinical Epidemiology and Applied Biometry, Eberhard Karls University Tübingen, Germany
| | - Konstanze Döhner
- University Hospital Ulm, Department of Internal Medicine III, Ulm, Germany
| | - Charles D. Lopez
- Department of Medicine, Division of Hematology and Medical Oncology, Oregon Health & Science University and The OHSU Knight Cancer Institute, Portland, Oregon, United States of America
| | - Kerstin M. Kampa-Schittenhelm
- University Hospital Tübingen, Department of Hematology, Oncology, Rheumatology, Immunology and Pulmology, Tübingen, Germany
- * E-mail:
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29
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Wang C, Gao C, Chen Y, Yin J, Wang P, Lv X. Expression pattern of the apoptosis-stimulating protein of p53 family in p53+ human breast cancer cell lines. Cancer Cell Int 2013; 13:116. [PMID: 24245874 PMCID: PMC4176745 DOI: 10.1186/1475-2867-13-116] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Accepted: 11/13/2013] [Indexed: 11/10/2022] Open
Abstract
Background The apoptosis-stimulating protein of p53 (ASPP) family comprises three members, namely, ASPP1, ASPP2, and iASPP. They regulate the promotive effect of p53 on apoptosis. Breast cancer (BC) remains as one of the leading causes of cancer or cancer-related mortality among women. However, the relationship between the ASPP family members and p53, as well as the dissemination and expression pattern of ASPP family members in p53+ BC, has not been elucidated. Our objectives are to detect the expression of ASPP family members in p53+ BC cell lines and determine its significance in tumor cell apoptosis. Methods The mRNA expression of ASPP family members in five p53+ BC cell lines was detected through RT-PCR and assayed using Quality-one software. The p53 protein expression was detected by immunohistochemistry. Afterward, the apoptosis indices of the five BC cell lines were detected by flow cytometry. Results The iASPP mRNA was expressed in Bcap-37, MCF-7, and HBL-100. Compared with the human peripheral blood mononuclear cells, significant differences were found in the ASPP1 mRNA in Bcap-37, MDA-MB-231, MCF-7, and HBL-100 (p < 0.05), except that in ZR-75-30 (p > 0.05). The ASPP2 mRNA was expressed in MDA-MB-231, Bcap-37, and MCF-7, but not in HBL-100 and ZR-75-30. The p53 protein was expressed in five breast cancer cell lines. ZR-75-30 and MDA-MB-231 apoptosis indices were higher than those of other breast cancer cell line and peripheral blood mononuclear cells (p < 0.01). Conclusions The mRNA expression of ASPP family members varied in the five p53+ BC cell lines. The results also verified that the family members have an important function in apoptosis, which was promoted by p53 protein. ZR-75-30 BC showed high apoptosis index, without expression of any ASPP family members, indicating that the pathway of apoptosis in this cell line may be related to other cell transduction pathway. MDA-MB-231, Bcap37, and MCF-7 cell lines all expressed ASPP1/2. However, the apoptosis pathway in MDA-MB-231 is different from those of the other two cell lines. The status of the different cell lines should also be considered when the functions of the ASPP family members are examined.
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Affiliation(s)
- Changsong Wang
- Department of Pathology, 150th Hospital of PLA, Luoyang, Henan Province, China.
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30
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Soldevilla B, Millán CS, Bonilla F, Domínguez G. The TP73 complex network: ready for clinical translation in cancer? Genes Chromosomes Cancer 2013; 52:989-1006. [PMID: 23913810 DOI: 10.1002/gcc.22095] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 06/28/2013] [Indexed: 01/05/2023] Open
Abstract
TP73 is a member of the TP53 family, whose deregulated expression has been reported in a wide variety of cancers and linked to patients' outcome. The fact that TP73 encodes a complex number of isoforms (TAp73 and ΔTAp73) with opposing functions and the cross-talk with other members of the family (TP53 and TP63) make it difficult to determine its clinical relevance. Here, we review the molecular mechanisms driving TAp73 and ΔTAp73 expression and how these variants inhibit or promote carcinogenesis. We also highlight the intricate interplay between TP53 family members. In addition, we comment on current pharmacological approaches targeting the TP73 pathway and those affecting the TAp73/ΔTAp73 ratio. Finally, we discuss the current data available in the literature that provide evidence on the role of TP73 variants in predicting prognosis. To date, most of the studies that evaluate the status levels of TP73 isoforms have been based on limited-size series. Despite this limitation, these publications highlight the correlation between high levels of the oncogenic forms and failure to respond to chemotherapy and/or shorter survival. Finally, we emphasize the need for studies to evaluate the significance of combining the deregulation of various members of the TP53 family in order to define patient outcome or their responsiveness to specific therapies.
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Affiliation(s)
- Beatriz Soldevilla
- Servicio de Oncología Médica, Hospital Universitario Puerta de Hierro Majadahonda, Madrid, Spain
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31
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Lu M, Breyssens H, Salter V, Zhong S, Hu Y, Baer C, Ratnayaka I, Sullivan A, Brown NR, Endicott J, Knapp S, Kessler BM, Middleton MR, Siebold C, Jones EY, Sviderskaya EV, Cebon J, John T, Caballero OL, Goding CR, Lu X. Restoring p53 function in human melanoma cells by inhibiting MDM2 and cyclin B1/CDK1-phosphorylated nuclear iASPP. Cancer Cell 2013; 23:618-33. [PMID: 23623661 DOI: 10.1016/j.ccr.2013.03.013] [Citation(s) in RCA: 115] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Revised: 10/05/2012] [Accepted: 03/15/2013] [Indexed: 12/20/2022]
Abstract
Nearly 90% of human melanomas contain inactivated wild-type p53, the underlying mechanisms for which are not fully understood. Here, we identify that cyclin B1/CDK1-phosphorylates iASPP, which leads to the inhibition of iASPP dimerization, promotion of iASPP monomer nuclear entry, and exposure of its p53 binding sites, leading to increased p53 inhibition. Nuclear iASPP is enriched in melanoma metastasis and associates with poor patient survival. Most wild-type p53-expressing melanoma cell lines coexpress high levels of phosphorylated nuclear iASPP, MDM2, and cyclin B1. Inhibition of MDM2 and iASPP phosphorylation with small molecules induced p53-dependent apoptosis and growth suppression. Concurrent p53 reactivation and BRAFV600E inhibition achieved additive suppression in vivo, presenting an alternative for melanoma therapy.
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Affiliation(s)
- Min Lu
- Ludwig Institute for Cancer Research, University of Oxford, Oxford OX3 7DQ, UK
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32
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Molecular mechanisms underlying the interaction of protein phosphatase-1c with ASPP proteins. Biochem J 2013; 449:649-59. [PMID: 23088536 DOI: 10.1042/bj20120506] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The serine/threonine PP-1c (protein phosphatase-1 catalytic subunit) is regulated by association with multiple regulatory subunits. Human ASPPs (apoptosis-stimulating proteins of p53) comprise three family members: ASPP1, ASPP2 and iASPP (inhibitory ASPP), which is uniquely overexpressed in many cancers. While ASPP2 and iASPP are known to bind PP-1c, we now identify novel and distinct molecular interactions that allow all three ASPPs to bind differentially to PP-1c isoforms and p53. iASPP lacks a PP-1c-binding RVXF motif; however, we show it interacts with PP-1c via a RARL sequence with a Kd value of 26 nM. Molecular modelling and mutagenesis of PP-1c-ASPP protein complexes identified two additional modes of interaction. First, two positively charged residues, Lys260 and Arg261 on PP-1c, interact with all ASPP family members. Secondly, the C-terminus of the PP-1c α, β and γ isoforms contain a type-2 SH3 (Src homology 3) poly-proline motif (PxxPxR), which binds directly to the SH3 domains of ASPP1, ASPP2 and iASPP. In PP-1cγ this comprises residues 309-314 (PVTPPR). When the Px(T)PxR motif is deleted or mutated via insertion of a phosphorylation site mimic (T311D), PP-1c fails to bind to all three ASPP proteins. Overall, we provide the first direct evidence for PP-1c binding via its C-terminus to an SH3 protein domain.
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33
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Rotem-Bamberger S, Katz C, Friedler A. Regulation of ASPP2 interaction with p53 core domain by an intramolecular autoinhibitory mechanism. PLoS One 2013; 8:e58470. [PMID: 23472201 PMCID: PMC3589414 DOI: 10.1371/journal.pone.0058470] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Accepted: 02/06/2013] [Indexed: 11/30/2022] Open
Abstract
ASPP2 is a key protein in regulating apoptosis both in p53-dependent and-independent pathways. The C-terminal part of ASPP2 contains four ankyrin repeats and an SH3 domain (Ank-SH3) that mediate the interactions of ASPP2 with apoptosis related proteins such as p53, Bcl-2 and the p65 subunit of NFκB. p53 core domain (p53CD) binds the n-src loop and the RT loop of ASPP2 SH3. ASPP2 contains a disordered proline rich domain (ASPP2 Pro) that forms an intramolecular autoinhibitory interaction with the Ank-SH3 domains. Here we show how this intramolecular interaction affects the intermolecular interactions of ASPP2 with p53, Bcl-2 and NFkB. We used biophysical methods to obtain better understanding of the relationship between ASPP2 and its partners for getting a comprehensive view on ASPP2 pathways. Fluorescence anisotropy competition experiments revealed that both ASPP2 Pro and p53CD competed for binding the n-src loop of the ASPP2 SH3, indicating regulation of p53CD binding to this loop by ASPP2 Pro. Peptides derived from the ASPP2-binding interface of Bcl-2 did not compete with p53CD or NFkB peptides for binding the ASPP2 n-src loop. However, p53CD displaced the NFκB peptide (residues 303–332) from its complex with ASPP2 Ank-SH3, indicating that NFκB 303–332 and p53CD bind a partly overlapping site in ASPP2 SH3, mostly in the RT loop. These results are in agreement with previous docking studies, which showed that ASPP2 Ank-SH3 binds Bcl-2 and NFκB mostly via distinct sites from p53. However they show some overlap between the binding sites of p53CD and NFkB in ASPP2 Ank-SH3. Our results provide experimental evidence that the intramolecular interaction in ASPP2 regulates its binding to p53CD and that ASPP2 Ank-SH3 binds Bcl-2 and NFκB via distinct sites.
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Affiliation(s)
- Shahar Rotem-Bamberger
- Institute of Chemistry, The Hebrew University of Jerusalem, Givat Ram, Jerusalem, Israel
| | - Chen Katz
- Institute of Chemistry, The Hebrew University of Jerusalem, Givat Ram, Jerusalem, Israel
| | - Assaf Friedler
- Institute of Chemistry, The Hebrew University of Jerusalem, Givat Ram, Jerusalem, Israel
- * E-mail:
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34
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Canning P, von Delft F, Bullock AN. Structural basis for ASPP2 recognition by the tumor suppressor p73. J Mol Biol 2012; 423:515-27. [PMID: 22917970 PMCID: PMC3472557 DOI: 10.1016/j.jmb.2012.08.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Revised: 08/03/2012] [Accepted: 08/13/2012] [Indexed: 11/27/2022]
Abstract
Tumor suppressors p53, p63 and p73 comprise a family of stress-responsive transcription factors with distinct functions in development and tumor suppression. Most human cancers lose p53 function, yet all three proteins are capable of inducing apoptosis or cellular senescence. Mechanisms are therefore under investigation to activate p73-dependent apoptosis in p53-deficient cancer cells. Significantly, the DNA-binding domain (DBD) of p73 escapes viral oncoproteins and displays an enhanced thermal stability. To further understand the variant features of p73, we solved the high-resolution crystal structure of the p73 DBD as well as its complex with the ankyrin repeat and SH3 domains of the pro-apoptotic factor ASPP2. The p73 structure exhibits the same conserved architecture as p53 but displays a divergent L2 loop, a known site of protein-protein interaction. The loop in p73 is changed by a two-residue insertion that also induces repacking around the site of the p53 mutational hotspot R175. Importantly, the binding of ASPP2 is preserved by conformational changes in both the ankyrin repeat and SH3 domains. These results further highlight the structural variation that impacts p53 family interactions within the p53 interactome.
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Affiliation(s)
| | | | - Alex N. Bullock
- Structural Genomics Consortium, University of Oxford, Old Road Campus, Roosevelt Drive, Oxford OX3 7DQ, UK
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Toonen J, Liang L, Sidjanin DJ. Waved with open eyelids 2 (woe2) is a novel spontaneous mouse mutation in the protein phosphatase 1, regulatory (inhibitor) subunit 13 like (Ppp1r13l) gene. BMC Genet 2012; 13:76. [PMID: 22928477 PMCID: PMC3469352 DOI: 10.1186/1471-2156-13-76] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Accepted: 07/24/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Waved with open eyelids 2 (woe2) is a novel autosomal recessive mouse mutation that arose spontaneously in our animal facility. Upon initial evaluation, mutant mice exhibited eyelids open at birth (EOB) and wavy fur phenotypes. The goals of this study were to phenotypically characterize the woe2 mice and to identify the gene harboring the mutation responsible for the woe2 phenotype. RESULTS Histological analysis of woe2 embryos identified the failure of embryonic eyelid closure. Clinical and histological analysis of woe2 adult eyes identified severe corneal opacities, abnormalities of the anterior segment of the eye, and the absence of meibomian glands. Abnormalities in the fur texture and the absence of meibomian glands prompted us to evaluate other epidermal appendages: skin, teeth, and nails--as well as lacrimal, mammary, salivary, sebaceous and sweat glands. No obvious morphological differences between WT and woe2 mice were identified in these tissues. However, the analysis of woe2 identified cardiac abnormalities. Positional cloning of the woe2 locus identified a 1308 bp deletion in the Ppp1r13l gene. The deletion resulted in an aberrant Ppp1r13l(Δexon9-11) transcript that lacks exons 9, 10 and 11 resulting in a premature stop and a loss of 223 amino acids from the C-terminal end of the putative mutant PPP1R13L protein. Immunohistological analysis during eye development identified expression of PPP1R13L in the palpebral epidermis, palpebral and bulbar conjunctiva, corneal epithelium and meibomian glands. CONCLUSIONS The woe2 mouse harbors a novel deletion within the Ppp1r13l gene, likely resulting in a complete loss of PPP1R13L function. Results from this study provide evidence that PPP1R13L has an essential role in embryonic eyelid closure as well in development of meibomian glands and the anterior segment of the eye. The woe2 mice are a useful model for investigation of the role of PPP1R13L, especially during ocular and eyelid development.
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Affiliation(s)
- Joseph Toonen
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, 8701 Watertown Plank Rd, Milwaukee, WI 53226, USA
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Patel JB, Patel KD, Patel SR, Shah FD, Shukla SN, Patel PS. Recent Candidate Molecular Markers: Vitamin D Signaling and Apoptosis Specific Regulator of p53 (ASPP) in Breast Cancer. Asian Pac J Cancer Prev 2012; 13:1727-35. [DOI: 10.7314/apjcp.2012.13.5.1727] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Cai Y, Qiu S, Gao X, Gu SZ, Liu ZJ. iASPP inhibits p53-independent apoptosis by inhibiting transcriptional activity of p63/p73 on promoters of proapoptotic genes. Apoptosis 2012; 17:777-83. [DOI: 10.1007/s10495-012-0728-z] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Beck B, Blanpain C. Mechanisms regulating epidermal stem cells. EMBO J 2012; 31:2067-75. [PMID: 22433839 DOI: 10.1038/emboj.2012.67] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Accepted: 02/27/2012] [Indexed: 12/17/2022] Open
Abstract
The skin epidermis contains different appendages such as the hair follicle and the sebaceous glands. Recent studies demonstrated that several types of stem cells (SCs) exist in different niches within the epidermis and maintain discrete epidermal compartments, but the exact contribution of each SC populations under physiological conditions is still unclear. In addition, the precise mechanisms controlling the balance between proliferation and differentiation of epidermal SC still remain elusive. Recent studies provide new insights into these important questions by showing the contribution of hair follicle SC to the sebaceous lineage and the importance of chromatin modifications and micro-RNAs (miRs) in regulating epidermal SCs renewal and differentiation. In this review, we will discuss the importance of these papers to our understanding of the mechanisms that control epidermal SC functions.
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Affiliation(s)
- Benjamin Beck
- Interdisciplinary Research Institute (IRIBHM), Université Libre de Bruxelles, Brussels, Belgium
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Rufini A, Agostini M, Grespi F, Tomasini R, Sayan BS, Niklison-Chirou MV, Conforti F, Velletri T, Mastino A, Mak TW, Melino G, Knight RA. p73 in Cancer. Genes Cancer 2011; 2:491-502. [PMID: 21779517 DOI: 10.1177/1947601911408890] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
p73 is a tumor suppressor belonging to the p53 family of transcription factors. Distinct isoforms are transcribed from the p73 locus. The use of 2 promoters at the N-terminus allows the expression of an isoform containing (TAp73) or not containing (ΔNp73) a complete N-terminal transactivation domain, with the latter isoform capable of a dominant negative effect over the former. In addition, both N-terminal variants are alternatively spliced at the C-terminus. TAp73 is a bona fide tumor suppressor, being able to induce cell death and cell cycle arrest; conversely, ΔNp73 shows oncogenic properties, inhibiting TAp73 and p53 functions. Here, we discuss the latest findings linking p73 to cancer. The generation of isoform specific null mice has helped in dissecting the contribution of TA versus ΔNp73 isoforms to tumorigenesis. The activity of both isoforms is regulated transcriptionally and by posttranslational modification. p73 dysfunction, particularly of TAp73, has been associated with mitotic abnormalities, which may lead to polyploidy and aneuploidy and thus contribute to tumorigenesis. Although p73 is only rarely mutated in cancer, the tumor suppressor actions of TAp73 are inhibited by mutant p53, a finding that has important implications for cancer therapy. Finally, we discuss the expression and role of p73 isoforms in human cancer, with a particular emphasis on the neuroblastoma cancer model. Broadly, the data support the hypothesis that the ratio between TAp73 and ΔNp73 is crucial for tumor progression and therapeutic response.
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Affiliation(s)
- Alessandro Rufini
- Toxicology Unit, Medical Research Council, Leicester, LE1 9HN, United Kingdom
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Bisso A, Collavin L, Del Sal G. p73 as a pharmaceutical target for cancer therapy. Curr Pharm Des 2011; 17:578-90. [PMID: 21391908 PMCID: PMC3267157 DOI: 10.2174/138161211795222667] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2011] [Accepted: 03/03/2011] [Indexed: 02/07/2023]
Abstract
About half of all human tumors contain an inactivating mutation of p53, while in the remaining tumors, the p53 pathway is frequently abrogated by alterations of other components of its signaling pathway. In humans, the p53 tumor suppressor is part of a small gene family that includes two other members, p73 and p63, structurally and functionally related to p53. Accumulating evidences indicate that all p53-family proteins function as molecular hubs of a highly interconnected signaling network that coordinates cell proliferation, differentiation and death in response to physiological inputs and oncogenic stress. Therefore, not only the p53-pathway but the entire “p53-family pathway” is a primary target for cancer drug development. In particular, the p53-related protein p73 has a crucial role in determining cellular responses to chemotherapy, and can vicariate p53 functions in triggering cell death after DNA damage in multiple experimental models. The biology and regulation of p73 is complex, since the TP73 gene incorporates both tumor-suppressive and proto-oncogenic functions. However, the p73 gene is rarely mutated in tumors, so appropriate pharmacological manipulation of the p73 pathway is a very promising approach for cancer therapy. Here we provide an overview of the principal mechanism of p73 regulation, and describe several examples of pharmacological tools that can induce p73 accumulation and function by acting on upstream p73 modulators or displacing inhibitory p73 interactors. A better understanding of how the p73 pathway works is mandatory to discover additional players intervening in this pathway and has important implications for the improvement of cancer treatment with the development of new molecules or with the reposition of currently available drugs.
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Affiliation(s)
- Andrea Bisso
- Laboratorio Nazionale CIB, AREA Science Park, Padriciano 99, Trieste, TS 34149, Italy
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Llanos S, Royer C, Lu M, Bergamaschi D, Lee WH, Lu X. Inhibitory member of the apoptosis-stimulating proteins of the p53 family (iASPP) interacts with protein phosphatase 1 via a noncanonical binding motif. J Biol Chem 2011; 286:43039-44. [PMID: 21998301 PMCID: PMC3234852 DOI: 10.1074/jbc.m111.270751] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Although kinase mutations have been identified in various human diseases, much less is known about protein phosphatases. Here, we show that all apoptosis-stimulating proteins of p53 (ASPP) family members can bind protein phosphatase 1 (PP1) via two distinct interacting motifs. ASPP2 interacts with PP1 through an RVXF PP1 binding motif, whereas the inhibitory member of the ASPP family (iASPP) interacts with PP1 via a noncanonical motif (RNYF) that is located within its Src homology 3 domain (SH3). Phe-815 is crucial in mediating iASPP/PP1 interaction, and iASPP(F815A) fails to inhibit the transcriptional and apoptotic function of p53. This study identifies iASPP as a new binding partner of PP1, interacting through a noncanonical PP1 binding motif.
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Affiliation(s)
- Susana Llanos
- Ludwig Institute for Cancer Research Ltd., Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, United Kingdom
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Inhibitor of apoptosis-stimulating protein of p53 (iASPP) prevents senescence and is required for epithelial stratification. Proc Natl Acad Sci U S A 2011; 108:16645-50. [PMID: 21930934 DOI: 10.1073/pnas.1102292108] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Inhibitor of apoptosis-stimulating protein of p53 (iASPP) is the most ancient member of the ASPP family of proteins and an evolutionarily conserved inhibitor of p53. iASPP is also a binding partner and negative regulator of p65RelA. Because p65RelA and the p53 family members often have opposite effects in controlling cell fate, it is important to understand the cellular context in which iASPP can regulate their activities. To address this question and to study the biological importance of iASPP in vivo, we generated a transgenic mouse in which iASPP expression is controlled by the Cre/loxP recombination system. We observed that iASPP is able to prevent premature cellular senescence in mouse embryonic fibroblasts. iASPP loss resulted in increased differentiation of primary keratinocytes both in vitro and in vivo. In stratified epithelia, nuclear iASPP often colocalized with p63 in the nuclei of basal keratinocytes. Consistent with this, iASPP bound p63 and inhibited the transcriptional activity of both TAp63α and ΔNp63α in vitro and influenced the expression level of p63-regulated genes such as loricrin and involucrin in vivo. In contrast, under the same conditions, p65RelA was frequently expressed as a cytoplasmic protein in the suprabasal layers of stratified epithelia and rarely colocalized with nuclear iASPP. Thus, iASPP is likely to control epithelial stratification by regulating p63's transcriptional activity, rather than p65RelA's. This study identifies iASPP as an inhibitor of senescence and a key player in controlling epithelial stratification.
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Jiang L, Siu MKY, Wong OGW, Tam KF, Lu X, Lam EWF, Ngan HYS, Le XF, Wong ESY, Monteiro LJ, Chan HY, Cheung ANY. iASPP and chemoresistance in ovarian cancers: effects on paclitaxel-mediated mitotic catastrophe. Clin Cancer Res 2011; 17:6924-33. [PMID: 21926165 DOI: 10.1158/1078-0432.ccr-11-0588] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE iASPP is a specific regulator of p53-mediated apoptosis. Herein, we provided the first report on the expression profile of iASPP in ovarian epithelial tumor and its effect on paclitaxel chemosensitivity. EXPERIMENTAL DESIGN Expression and amplification status of iASPP was examined in 203 clinical samples and 17 cell lines using immunohistochemistry, quantitative real-time PCR, and immunoblotting, and correlated with clinicopathologic parameters. Changes in proliferation, mitotic catastrophe, apoptosis, and underlying mechanism in ovarian cancer cells of different p53 status following paclitaxel exposure were also analyzed. RESULTS The protein and mRNA expression of iASPP was found to be significantly increased in ovarian cancer samples and cell lines. High iASPP expression was significantly associated with clear cell carcinoma subtype (P = 0.003), carboplatin and paclitaxel chemoresistance (P = 0.04), shorter overall (P = 0.003), and disease-free (P = 0.001) survival. Multivariate analysis confirmed iASPP expression as an independent prognostic factor. Increased iASPP mRNA expression was significantly correlated with gene amplification (P = 0.023). iASPP overexpression in ovarian cancer cells conferred resistance to paclitaxel by reducing mitotic catastrophe in a p53-independent manner via activation of separase, whereas knockdown of iASPP enhanced paclitaxel-mediated mitotic catastrophe through inactivating separase. Both securin and cyclin B1/CDK1 complex were involved in regulating separase by iASPP. Conversely, overexpressed iASPP inhibited apoptosis in a p53-dependent mode. CONCLUSIONS Our data show an association of iASPP overexpression with gene amplification in ovarian cancer and suggest a role of iASPP in poor patient outcome and chemoresistance, through blocking mitotic catastrophe. iASPP should be explored further as a potential prognostic marker and target for chemotherapy.
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Affiliation(s)
- Lili Jiang
- Department of Pathology, The University of Hong Kong, Hong Kong Special Administrative Region, China
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iASPP/p63 autoregulatory feedback loop is required for the homeostasis of stratified epithelia. EMBO J 2011; 30:4261-73. [PMID: 21897369 DOI: 10.1038/emboj.2011.302] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Accepted: 07/22/2011] [Indexed: 11/08/2022] Open
Abstract
iASPP, an inhibitory member of the ASPP (apoptosis stimulating protein of p53) family, is an evolutionarily conserved inhibitor of p53 which is frequently upregulated in human cancers. However, little is known about the role of iASPP under physiological conditions. Here, we report that iASPP is a critical regulator of epithelial development. We demonstrate a novel autoregulatory feedback loop which controls crucial physiological activities by linking iASPP to p63, via two previously unreported microRNAs, miR-574-3p and miR-720. By investigating its function in stratified epithelia, we show that iASPP participates in the p63-mediated epithelial integrity program by regulating the expression of genes essential for cell adhesion. Silencing of iASPP in keratinocytes by RNA interference promotes and accelerates a differentiation pathway, which also affects and slowdown cellular proliferation. Taken together, these data reveal iASPP as a key regulator of epithelial homeostasis.
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Benyamini H, Friedler A. The ASPP interaction network: electrostatic differentiation between pro- and anti-apoptotic proteins. J Mol Recognit 2011; 24:266-74. [PMID: 20623514 DOI: 10.1002/jmr.1048] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The ASPP proteins are apoptosis regulators: ASPP1 and ASPP2 promote, while iASPP inhibits, apoptosis. The mechanism by which these different outcomes are achieved is still unknown. The C-terminal ankyrin repeats and SH3 domain (ANK-SH3) mediate the interactions of the ASPP proteins with major apoptosis regulators such as p53, Bcl-2, and NFκB. The structure of the complex between ASPP2(ANK-SH3) and the core domain of p53 (p53CD) was previously determined. We have recently characterized the individual interactions of ASPP2(ANK-SH3) with Bcl-2 and NFκB, as well as a regulatory intramolecular interaction with the proline rich domain of ASPP2. Here we compared the ASPP interactions at two levels: ASPP2(ANK-SH3) with different proteins, and different ASPP family members with each protein partner. We found that the binding sites of ASPP2 to p53CD, Bcl-2, and NFκB are different, yet lie on the same face of ASPP2(ANK-SH3) . The intramolecular binding site to the proline rich domain overlaps the three intermolecular binding sites. To reveal the basis of functional diversity in the ASPP family, we compared their protein-binding domains. A subset of surface-exposed residues differentiates ASPP1 and ASPP2 from iASPP: ASPP1/2 are more negatively charged in specific residues that contact positively charged residues of p53CD, Bcl-2, and NFκB. We also found a gain of positive charge at the non-protein binding face of ASPP1/2, suggesting a role in electrostatic direction towards the negatively charged protein binding face. The electrostatic differences in binding interfaces between the ASPP proteins may be one of the causes for their different function.
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Affiliation(s)
- Hadar Benyamini
- The Institute of Chemistry, The Hebrew University of Jerusalem, Safra Campus, Givat Ram, Jerusalem 91904, Israel
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Gillotin S, Lu X. The ASPP proteins complex and cooperate with p300 to modulate the transcriptional activity of p53. FEBS Lett 2011; 585:1778-82. [PMID: 21513714 DOI: 10.1016/j.febslet.2011.04.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2011] [Revised: 03/30/2011] [Accepted: 04/05/2011] [Indexed: 11/25/2022]
Abstract
Understanding how p53 is able to specifically respond to particular stress signals and regulate many different signalling pathways remains a challenge. Several studies have demonstrated that p53's interactions with different protein partners are essential for it to be able to coordinate specific responses. In particular, the apoptotic pathway is regulated by p53 in cooperation with the Apoptosis Stimulating Proteins of p53 (ASPP) proteins. In this study, we showed that the ASPP proteins are able to bind and cooperate with p300, a well defined co-factor of p53, to selectively regulate p53's transcriptional activity on promoters such as p53-inducible gene 3 but not on p21waf1. This is the first demonstration that the ASPPs can function together with p300 in regulating the transcriptional activity of p53.
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Affiliation(s)
- Sébastien Gillotin
- Ludwig Institute for Cancer Research Ltd., University of Oxford, The Nuffield Department of Clinical Medicine, Oxford, United Kingdom
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Martinez JD. Restoring p53 tumor suppressor activity as an anticancer therapeutic strategy. Future Oncol 2011; 6:1857-62. [PMID: 21142860 DOI: 10.2217/fon.10.132] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Loss of p53 tumor suppressor function is a key event in the genesis of most human tumors. This observation has prompted efforts to restore p53 activity as an anticancer therapeutic approach. Recent developments that have extended our understanding of how p53 activity is regulated and how mutations disrupt that regulation have provided the insight needed to develop therapeutic strategies that take advantage of this knowledge. In this article, we review the strategies for restoring p53 function and some of the new compounds that show promise as antitumor agents in preclinical models.
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Affiliation(s)
- Jesse D Martinez
- University of Arizona, Arizona Cancer Center, 1515 North Campbell Avenue, Tucson, AZ 85724, USA.
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Chen J, Xie F, Zhang L, Jiang WG. iASPP is over-expressed in human non-small cell lung cancer and regulates the proliferation of lung cancer cells through a p53 associated pathway. BMC Cancer 2010; 10:694. [PMID: 21192816 PMCID: PMC3022889 DOI: 10.1186/1471-2407-10-694] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Accepted: 12/30/2010] [Indexed: 11/12/2022] Open
Abstract
Background iASPP is a key inhibitor of tumour suppressor p53 and is found to be up-regulated in certain malignant conditions. The present study investigated the expression of iASPP in clinical lung cancer, a leading cancer type in the world, and the biological impact of this molecule on lung cancer cells. Methods iASPP protein levels in lung cancer tissues were evaluated using an immunohistochemical method. In vitro, iASPP gene expression was suppressed with a lentvirus-mediated shRNA method and the biological impact after knocking down iASSP on lung cancer cell lines was investigated in connection with the p53 expression status. Results We showed here that the expression of iASPP was significantly higher in lung cancer tissues compared with the adjacent normal tissues. iASPP shRNA treatment resulted in a down-regulation of iASPP in lung cancer cells. There was a subsequent reduction of cell proliferation of the two lung tumour cell lines A459 and 95D both of which had wild-type p53 expression. In contrast, reduction of iASPP in H1229 cells, a cell with little p53 expression, had no impact on its growth rate. Conclusions iASPP regulates the proliferation and motility of lung cancer cells. This effect is intimately associated with the p53 pathway. Together with the pattern of the over-expression in clinical lung cancers, it is concluded that iASPP plays an pivotal role in the progression of lung cancer and is a potential target for lung cancer therapy.
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Affiliation(s)
- Jinfeng Chen
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Thoracic Surgery, Peking University School of Oncology and Beijing Cancer Hospital & Institute Beijing, 100142 PR China
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Lu B, Guo H, Zhao J, Wang C, Wu G, Pang M, Tong X, Bu F, Liang A, Hou S, Fan X, Dai J, Wang H, Guo Y. Increased expression of iASPP, regulated by hepatitis B virus X protein-mediated NF-κB activation, in hepatocellular carcinoma. Gastroenterology 2010; 139:2183-2194.e5. [PMID: 20600029 DOI: 10.1053/j.gastro.2010.06.049] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2009] [Revised: 05/27/2010] [Accepted: 06/10/2010] [Indexed: 12/02/2022]
Abstract
BACKGROUND & AIMS iASPP is an inhibitory member of the ankyrin-repeat-, SH3-domain- and proline-rich-region-containing protein (ASPP) family; iASPP expression is up-regulated in different human tumor types. We explored the molecular mechanism increased expression of iASPP and its role in hepatocellular carcinoma (HCC). METHODS iASPP expression levels in human liver samples and cell lines were determined by polymerase chain reaction, immunoblot, and immunohistochemical analyses. Luciferase reporter, chromatin immunoprecipitation, and electrophoretic mobility shift assays were used to measure transcriptional activation by nuclear factor-κB (NF-κB). Effects on tumor growth were characterized with MTS, soft agar colony formation, and flow cytometry analyses. Tumorigenicity of cells was studied in nude mice. RESULTS Compared with normal liver cells or tissues, iASPP was expressed at significantly higher levels in HCC cell lines (9/14) and liver samples from patients with HCC, cirrhosis, or hepatitis B virus infection. Increased expression of iASPP was significantly associated with time to recurrence and survival time of patients with HCC. NF-κB activation increased the expression of iASPP through p65/p50 binding to a putative NF-κB-binding site in the iASPP promoter; hepatitis B virus X gene product might up-regulate expression of iASPP. Transgenic expression of iASPP promoted tumor cell proliferation and resistance to chemotherapeutic drugs in vitro and in vivo. CONCLUSIONS iASPP is up-regulated in HCC; it is a direct transcription target of NF-κB. Increased iASPP expression contributes to tumor progression by proliferative and antiapoptotic effects. iASPP might be developed as an HCC therapeutic target or to sensitize cancer cells to chemotherapeutic drugs; it might also be used as a prognostic factor.
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Affiliation(s)
- Bin Lu
- International Joint Cancer Institute, The Second Military Medical University, Shanghai, China
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Collavin L, Lunardi A, Del Sal G. p53-family proteins and their regulators: hubs and spokes in tumor suppression. Cell Death Differ 2010; 17:901-11. [PMID: 20379196 DOI: 10.1038/cdd.2010.35] [Citation(s) in RCA: 168] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The tumor suppressor p53 is a central hub in a molecular network controlling cell proliferation and death in response to potentially oncogenic conditions, and a wide array of covalent modifications and protein interactions modulate the nuclear and cytoplasmic activities of p53. The p53 relatives, p73 and p63, are entangled in the same regulatory network, being subject at least in part to the same modifications and interactions that convey signals on p53, and actively contributing to the resulting cellular output. The emerging picture is that of an interconnected pathway, in which all p53-family proteins are involved in the response to oncogenic stress and physiological inputs. Therefore, common and specific interactors of p53-family proteins can have a wide effect on function and dysfunction of this pathway. Many years of research have uncovered an impressive number of p53-interacting proteins, but much less is known about protein interactions of p63 and p73. Yet, many interactors may be shared by multiple p53-family proteins, with similar or different effects. In this study we review shared interactors of p53-family proteins with the aim to encourage research into this field; this knowledge promises to unveil regulatory elements that could be targeted by a new generation of molecules, and allow more efficient use of currently available drugs for cancer treatment.
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Affiliation(s)
- L Collavin
- Laboratorio Nazionale CIB, AREA Science Park, Trieste, Italy
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