1
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Alfadul SM, Matnurov EM, Varakutin AE, Babak MV. Metal-Based Anticancer Complexes and p53: How Much Do We Know? Cancers (Basel) 2023; 15:2834. [PMID: 37345171 DOI: 10.3390/cancers15102834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 05/15/2023] [Accepted: 05/17/2023] [Indexed: 06/23/2023] Open
Abstract
P53 plays a key role in protecting the human genome from DNA-related mutations; however, it is one of the most frequently mutated genes in cancer. The P53 family members p63 and p73 were also shown to play important roles in cancer development and progression. Currently, there are various organic molecules from different structural classes of compounds that could reactivate the function of wild-type p53, degrade or inhibit mutant p53, etc. It was shown that: (1) the function of the wild-type p53 protein was dependent on the presence of Zn atoms, and (2) Zn supplementation restored the altered conformation of the mutant p53 protein. This prompted us to question whether the dependence of p53 on Zn and other metals might be used as a cancer vulnerability. This review article focuses on the role of different metals in the structure and function of p53, as well as discusses the effects of metal complexes based on Zn, Cu, Fe, Ru, Au, Ag, Pd, Pt, Ir, V, Mo, Bi and Sn on the p53 protein and p53-associated signaling.
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Affiliation(s)
- Samah Mutasim Alfadul
- Drug Discovery Lab, Department of Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong SAR 999077, China
| | - Egor M Matnurov
- Drug Discovery Lab, Department of Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong SAR 999077, China
| | - Alexander E Varakutin
- Drug Discovery Lab, Department of Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong SAR 999077, China
| | - Maria V Babak
- Drug Discovery Lab, Department of Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong SAR 999077, China
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2
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Miller JJ, Kwan K, Gaiddon C, Storr T. A role for bioinorganic chemistry in the reactivation of mutant p53 in cancer. J Biol Inorg Chem 2022; 27:393-403. [PMID: 35488931 DOI: 10.1007/s00775-022-01939-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 04/11/2022] [Indexed: 12/19/2022]
Abstract
Metal ion dysregulation has been implicated in a number of diseases from neurodegeneration to cancer. While defective metal ion transport mechanisms are known to cause specific diseases of genetic origin, the role of metal dysregulation in many diseases has yet to be elucidated due to the complicated function (both good and bad!) of metal ions in the body. A breakdown in metal ion speciation can manifest in several ways from increased reactive oxygen species (ROS) generation to an increase in protein misfolding and aggregation. In this review, we will discuss the role of Zn in the proper function of the p53 protein in cancer. The p53 protein plays a critical role in the prevention of genome mutations via initiation of apoptosis, DNA repair, cell cycle arrest, anti-angiogenesis, and senescence pathways to avoid propagation of damaged cells. p53 is the most frequently mutated protein in cancer and almost all cancers exhibit malfunction along the p53 pathway. Thus, there has been considerable effort dedicated to restoring normal p53 expression and activity to mutant p53. This includes understanding the relative populations of the Zn-bound and Zn-free p53 in wild-type and mutant forms, and the development of metallochaperones to re-populate the Zn binding site to restore mutant p53 activity. Parallels will be made to the development of multifunctional metal binding agents for modulating the aggregation of the amyloid-beta peptide in Alzheimer's Disease (AD).
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Affiliation(s)
- Jessica J Miller
- Department of Chemistry, Simon Fraser University, Burnaby, BC, V5A 1S6, Canada
| | - Kalvin Kwan
- Department of Chemistry, Simon Fraser University, Burnaby, BC, V5A 1S6, Canada
| | - Christian Gaiddon
- Inserm UMR_S1113, IRFAC, team Streinth, Strasbourg University, Strasbourg, France
| | - Tim Storr
- Department of Chemistry, Simon Fraser University, Burnaby, BC, V5A 1S6, Canada.
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3
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Zinc ionophores: chemistry and biological applications. J Inorg Biochem 2021; 228:111691. [PMID: 34929542 DOI: 10.1016/j.jinorgbio.2021.111691] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 12/01/2021] [Accepted: 12/03/2021] [Indexed: 02/06/2023]
Abstract
Zinc can play a pathophysiological role in several diseases and can interfere in key processes of microbial growth. This evidence justifies the efforts in applying Zinc ionophores to restore Zinc homeostasis and treat bacterial/viral infections such as coronavirus diseases. Zinc ionophores increase the intracellular concentration of Zinc ions causing significant biological effects. This review provides, for the first time, an overview of the applications of the main Zinc ionophores in Zinc deficiency, infectious diseases, and in cancer, discussing the pharmacological and coordination properties of the Zinc ionophores.
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4
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Jankovic-Karasoulos T, McAninch D, Dixon C, Leemaqz SYL, François M, Leifert WR, McCullough D, Ricciardelli C, Roberts CT, Bianco-Miotto T. The effect of zinc on human trophoblast proliferation and oxidative stress. J Nutr Biochem 2020; 90:108574. [PMID: 33388345 DOI: 10.1016/j.jnutbio.2020.108574] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 10/26/2020] [Accepted: 12/24/2020] [Indexed: 10/22/2022]
Abstract
Adequate Zinc (Zn) intake is required to prevent multiple teratogenic effects however deviations from adequate Zn intake, including high maternal Zn status, have been linked to increased incidence of pregnancy complications, including those associated with inadequate placentation. Using placental trophoblast HTR8/SVneo cells and first trimester human placental explants (n = 12), we assessed the effects of varying Zn concentrations on trophoblast proliferation, viability, apoptosis and oxidative stress. Compared to physiologically normal Zn levels (20 µM), HTR-8/SVneo cell proliferation index was significantly lower in the presence of physiologically elevated (40 µM; P = .020) and supra-physiological (80 µM; P = .007) Zn. The latter was also associated with reduced proliferation (P = .004) and viability (P < .0001) in cultured placental explants, but not apoptosis. Reactive oxygen species production in HTR8/SVneo cultures was significantly higher in the presence of 80 µM Zn compared to all physiologically relevant levels. Oxidative stress, induced by an oxidizing agent menadione, was further exacerbated by high (80 µM) Zn. Zn did not affect lipid peroxidation in either HTR8/SVneo cells or placental explants or antioxidant defense mechanisms that included glutathione reductase and superoxide dismutase. Further study should focus on elucidating mechanisms behind impaired trophoblast proliferation and increased oxidative stress as a result of elevated Zn levels.
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Affiliation(s)
- Tanja Jankovic-Karasoulos
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA, Australia; Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia; Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - Dale McAninch
- Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia; Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - Clare Dixon
- Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia; School of Agriculture, Food and Wine, Waite Research Institute, University of Adelaide, Adelaide, SA, Australia
| | - Shalem Y-L Leemaqz
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA, Australia; Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia; Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - Maxime François
- School of Agriculture, Food and Wine, Waite Research Institute, University of Adelaide, Adelaide, SA, Australia; CSIRO Health and Biosecurity, Future Science Platforms Probing Biosystems, Adelaide, SA, Australia
| | - Wayne R Leifert
- CSIRO Health and Biosecurity, Future Science Platforms Probing Biosystems, Adelaide, SA, Australia; School of Biological Sciences, University of Adelaide, Adelaide, SA, Australia
| | - Dylan McCullough
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA, Australia; Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia; Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - Carmela Ricciardelli
- Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia; Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - Claire T Roberts
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA, Australia; Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia; Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia.
| | - Tina Bianco-Miotto
- Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia; School of Agriculture, Food and Wine, Waite Research Institute, University of Adelaide, Adelaide, SA, Australia.
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5
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Fan L, Qin JC, Li CR, Yang ZY. Two similar Schiff-base receptor based quinoline derivate: Highly selective fluorescent probe for Zn(II). SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2020; 236:118347. [PMID: 32305837 DOI: 10.1016/j.saa.2020.118347] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 03/31/2020] [Accepted: 04/06/2020] [Indexed: 06/11/2023]
Abstract
As is known, Zn2+ plays a vital role in a variety of biological processes but excessive exposure of Zn2+ to human beings can cause toxicity, inducing a series of overt poisoning symptoms and neurodegenerative disorders. Thus, we designed and synthesized two quinoline-derived Schiff-bases HL1 and HL2, and investigated the fluorescence emission responses of these two Schiff-bases to various metal ions. A significant enhancement in fluorescence emission band centered at 450 nm was observed in the ethanolic solution of HL1 with addition of Zn2+, while remarkably lower fluorescence emission enhancement was obtained in the case of HL2 in which one methyl group was introduced to the azomethine carbon. In addition, HL1 showed good selectivity and high sensitivity towards Zn2+ in the existence of other various interfering metal ions, and the reversibility and regeneration of HL1 were also perfect for extending its applications in environmental and biological systems. Therefore, HL1 could be identified as a fluorescent probe for sensing Zn2+ environmentally and biologically.
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Affiliation(s)
- Long Fan
- College of Chemistry and Chemical Engineering, State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, PR China; Quality and Technical Supervision and Inspection of Jin Chang, Jin Chang 737100, PR China
| | - Jing-Can Qin
- College of Chemistry and Chemical Engineering, State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, PR China
| | - Chao-Rui Li
- College of Chemistry and Chemical Engineering, State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, PR China
| | - Zheng-Yin Yang
- College of Chemistry and Chemical Engineering, State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, PR China.
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6
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Biophysical characterization of p53 core domain aggregates. Biochem J 2020; 477:111-120. [PMID: 31841126 DOI: 10.1042/bcj20190778] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 12/12/2019] [Accepted: 12/13/2019] [Indexed: 12/16/2022]
Abstract
Aggregation is the cause of numerous protein conformation diseases. A common facet of these maladies is the transition of a protein from its functional native state into higher order forms, such as oligomers and amyloid fibrils. p53 is an essential tumor suppressor that is prone to such conformational transitions, resulting in its compromised ability to avert cancer. This work explores the biophysical properties of early-, mid-, and late-stage p53 core domain (p53C) aggregates. Atomistic and coarse-grained molecular dynamics (MD) simulations suggest that early- and mid-stage p53C aggregates have a polymorphic topology of antiparallel and parallel β-sheets that localize to the core amyloidogenic sequence. Both topologies involve similar extents of interstrand mainchain hydrogen bonding, while sidechain interactions could play a role in regulating strand orientation. The free energy difference between the antiparallel and parallel states was within statistical uncertainty. Negative stain electron microscopy of mature fibrils shows a wide distribution of fiber widths, indicating that polymorphism may extend to the quaternary structure level. Circular dichroism of the fibrils was indicative of β-sheet rich structures in atypical conformations. The Raman spectrum of aggregated p53C was consistent with a mixture of arranged β-sheets and heterogeneous structural elements, which is compatible with the MD findings of an ordered β-sheet nucleus flanked by disordered structure. Structural polymorphism is a common property of amyloids; however, because certain polymorphs of the same protein can be more harmful than others, going forward it will be pertinent to establish correlations between p53C aggregate structure and pathology.
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7
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Kong LR, Ong RW, Tan TZ, Mohamed Salleh NAB, Thangavelu M, Chan JV, Koh LYJ, Periyasamy G, Lau JA, Le TBU, Wang L, Lee M, Kannan S, Verma CS, Lim CM, Chng WJ, Lane DP, Venkitaraman A, Hung HT, Cheok CF, Goh BC. Targeting codon 158 p53-mutant cancers via the induction of p53 acetylation. Nat Commun 2020; 11:2086. [PMID: 32350249 PMCID: PMC7190866 DOI: 10.1038/s41467-020-15608-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 03/19/2020] [Indexed: 12/14/2022] Open
Abstract
Gain of function (GOF) DNA binding domain (DBD) mutations of TP53 upregulate chromatin regulatory genes that promote genome-wide histone methylation and acetylation. Here, we therapeutically exploit the oncogenic GOF mechanisms of p53 codon 158 (Arg158) mutation, a DBD mutant found to be prevalent in lung carcinomas. Using high throughput compound screening and combination analyses, we uncover that acetylating mutp53R158G could render cancers susceptible to cisplatin-induced DNA stress. Acetylation of mutp53R158G alters DNA binding motifs and upregulates TRAIP, a RING domain-containing E3 ubiquitin ligase which dephosphorylates IĸB and impedes nuclear translocation of RelA (p65), thus repressing oncogenic nuclear factor kappa-B (NF-ĸB) signaling and inducing apoptosis. Given that this mechanism of cytotoxic vulnerability appears inapt in p53 wild-type (WT) or other hotspot GOF mutp53 cells, our work provides a therapeutic opportunity specific to Arg158-mutp53 tumors utilizing a regimen consisting of DNA-damaging agents and mutp53 acetylators, which is currently being pursued clinically. Codon 158 gain-of-function mutant p53 (158-mutp53) promotes tumourigenesis in lung cancer. Here, the authors show that 158-mutp53 render cancers sensitive to cisplatin and p53 acetylation agents through a mechanism where acetylated mutant p53 upregulates TRAIP and inhibits NF-ĸB signaling.
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Affiliation(s)
- Li Ren Kong
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, 117599, Singapore. .,Medical Research Council Cancer Unit, University of Cambridge, Cambridge, CB2 0XZ, UK.
| | - Richard Weijie Ong
- Laboratory of Molecular Endocrinology, National Cancer Centre Singapore, Singapore, Singapore
| | - Tuan Zea Tan
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, 117599, Singapore
| | | | - Matan Thangavelu
- Genome Institute of Singapore, Agency for Science, Technology & Research (A*STAR), Singapore, 138672, Singapore
| | - Jane Vin Chan
- Genome Institute of Singapore, Agency for Science, Technology & Research (A*STAR), Singapore, 138672, Singapore
| | - Lie Yong Judice Koh
- Genome Institute of Singapore, Agency for Science, Technology & Research (A*STAR), Singapore, 138672, Singapore
| | - Giridharan Periyasamy
- Genome Institute of Singapore, Agency for Science, Technology & Research (A*STAR), Singapore, 138672, Singapore
| | - Jieying Amelia Lau
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, 117599, Singapore
| | - Thi Bich Uyen Le
- Laboratory of Molecular Endocrinology, National Cancer Centre Singapore, Singapore, Singapore
| | - Lingzhi Wang
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, 117599, Singapore.,Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117597, Singapore
| | - Miyoung Lee
- Medical Research Council Cancer Unit, University of Cambridge, Cambridge, CB2 0XZ, UK
| | - Srinivasaraghavan Kannan
- Bioinformatics Institute, Agency for Science, Technology, and Research (A*STAR), Singapore, 138671, Singapore
| | - Chandra S Verma
- Bioinformatics Institute, Agency for Science, Technology, and Research (A*STAR), Singapore, 138671, Singapore.,Department of Biological Sciences, National University of Singapore, Singapore, 117558, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, 639798, Singapore
| | - Chwee Ming Lim
- Division of Surgical Oncology (Head and Neck Surgery), National University Cancer Institute, Singapore (NCIS), Singapore, 119074, Singapore
| | - Wee Joo Chng
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, 117599, Singapore.,Department of Haematology-Oncology, National University Cancer Institute, Singapore, 119074, Singapore.,Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119228, Singapore
| | - David P Lane
- p53 Laboratory (p53Lab), Agency for Science, Technology, and Research (A*STAR), Singapore, 138648, Singapore
| | - Ashok Venkitaraman
- Medical Research Council Cancer Unit, University of Cambridge, Cambridge, CB2 0XZ, UK
| | - Huynh The Hung
- Laboratory of Molecular Endocrinology, National Cancer Centre Singapore, Singapore, Singapore
| | - Chit Fang Cheok
- Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology, and Research (A*STAR), Singapore, 138673, Singapore.,Department of Pathology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119074, Singapore.,Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117596, Singapore
| | - Boon Cher Goh
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, 117599, Singapore. .,Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117597, Singapore. .,Department of Haematology-Oncology, National University Cancer Institute, Singapore, 119074, Singapore.
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8
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Ohanian M, Telouk P, Kornblau S, Albarede F, Ruvolo P, Tidwell RSS, Plesa A, Kanagal-Shamanna R, Matera EL, Cortes J, Carson A, Dumontet C. A heavy metal baseline score predicts outcome in acute myeloid leukemia. Am J Hematol 2020; 95:422-434. [PMID: 31944361 DOI: 10.1002/ajh.25731] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 11/26/2019] [Accepted: 01/08/2020] [Indexed: 02/06/2023]
Abstract
Despite abundant epidemiological data linking metals to leukemia and other cancers, baseline values of toxic and essential metals in patients with leukemia and the clinical impact of these metals remain unknown. Thus, we sought to quantify metal values in untreated patients with acute myeloid leukemia (AML) and controls and determine the impact of metal values on AML patients' survival. Serum samples from patients with untreated AML and controls at Hospices Civils de Lyon were analyzed and compared for trace metals and copper isotopic abundance ratios with inductively coupled plasma mass spectrometry. Survival analysis was performed as a function of metal values, and a multi-metal score was developed for patients with AML. Serum samples were collected from 67 patients with untreated AML and 94 controls. Most patients had intermediate-risk cytogenetics (63.1%) without FLT3 internal tandem duplication mutations (75.6%) or NPM1 mutations (68.1%). Most metal values differed significantly between AML and control groups. Patients with lower magnesium and higher cadmium values had the worst survival rates, with only 36% surviving at 6 months (P = .001). The adverse prognostic effect of this combination was maintained on multivariate analysis. Based on this, we developed a novel metal score, which accounts for multiple relative abnormalities in the values of five toxic and five essential metals. Patients with a higher metal score had significantly worse survival, which was maintained on multivariate analysis (P = .03). This baseline metal scoring system was also prognostic when we applied it to a separate population of front-line AML patients.
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Affiliation(s)
- Maro Ohanian
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Philippe Telouk
- Department of Géosciences, École Normal Supérieure de Lyon, Lyon, France
| | - Steven Kornblau
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Francis Albarede
- Department of Géosciences, École Normal Supérieure de Lyon, Lyon, France
| | - Peter Ruvolo
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Rebecca S S Tidwell
- Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Adriana Plesa
- CRCL, INSERM 1052/CNRS 5286, Hospices Civils de Lyon, Lyon, France
| | - Rashmi Kanagal-Shamanna
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Eva-Laure Matera
- CRCL, INSERM 1052/CNRS 5286, Hospices Civils de Lyon, Lyon, France
| | | | - Arch Carson
- Department of Epidemiology, Human Genetics and Environmental Sciences, The University of Texas School of Public Health, Houston, Texas
| | - Charles Dumontet
- CRCL, INSERM 1052/CNRS 5286, Hospices Civils de Lyon, Lyon, France
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9
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Loh SN. Follow the Mutations: Toward Class-Specific, Small-Molecule Reactivation of p53. Biomolecules 2020; 10:biom10020303. [PMID: 32075132 PMCID: PMC7072143 DOI: 10.3390/biom10020303] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 02/09/2020] [Accepted: 02/11/2020] [Indexed: 12/17/2022] Open
Abstract
The mutational landscape of p53 in cancer is unusual among tumor suppressors because most of the alterations are of the missense type and localize to a single domain: the ~220 amino acid DNA-binding domain. Nearly all of these mutations produce the common effect of reducing p53’s ability to interact with DNA and activate transcription. Despite this seemingly simple phenotype, no mutant p53-targeted drugs are available to treat cancer patients. One of the main reasons for this is that the mutations exert their effects via multiple mechanisms—loss of DNA contacts, reduction in zinc-binding affinity, and lowering of thermodynamic stability—each of which involves a distinct type of physical impairment. This review discusses how this knowledge is informing current efforts to develop small molecules that repair these defects and restore function to mutant p53. Categorizing the spectrum of p53 mutations into discrete classes based on their inactivation mechanisms is the initial step toward personalized cancer therapy based on p53 allele status.
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Affiliation(s)
- Stewart N Loh
- Department of Biochemistry and Molecular Biology, State University of New York Upstate Medical University, Syracuse, NY 13210, USA
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10
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Navalkar A, Ghosh S, Pandey S, Paul A, Datta D, Maji SK. Prion-like p53 Amyloids in Cancer. Biochemistry 2019; 59:146-155. [DOI: 10.1021/acs.biochem.9b00796] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Ambuja Navalkar
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai, India 400076
| | - Saikat Ghosh
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai, India 400076
| | - Satyaprakash Pandey
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai, India 400076
| | - Ajoy Paul
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai, India 400076
| | - Debalina Datta
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai, India 400076
| | - Samir K. Maji
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai, India 400076
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11
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Wu H, Dyson HJ. Aggregation of zinc-free p53 is inhibited by Hsp90 but not other chaperones. Protein Sci 2019; 28:2020-2023. [PMID: 31503385 DOI: 10.1002/pro.3726] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 09/04/2019] [Accepted: 09/07/2019] [Indexed: 11/09/2022]
Abstract
The structured DNA-binding domain (DBD) of p53 is a well-known client protein of the chaperone Hsp90. The p53 DBD contains a single zinc ion, coordinated by the side chains of Cys176, His179, Cys238, and Cys242; zinc coordination plays a structural role to stabilize the DBD and is required for its DNA binding. The ambiguous nature of the p53-Hsp90 interaction, together with the stabilizing role of the zinc in the structure of the DBD, prompted us to examine the interaction of Hsp90 with zinc-free p53 DBD. NMR spectroscopy and native gel electrophoresis did not show any apparent preference for the interaction of the destabilized zinc-free form of p53 DBD with Hsp90. Intriguingly, however, at lower protein concentrations, closer to physiological concentrations, the addition of Hsp90, but not other chaperones such as Hsp70, Hsp40, p23, and HOP, appears to slow or prevent the aggregation of zinc-free p53 DBD. This result suggests that part of the function of the Hsp90-p53 interaction in the cell may be to stabilize the apoprotein in the absence of zinc.
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Affiliation(s)
- Huiwen Wu
- Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, California
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12
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Adulcikas J, Sonda S, Norouzi S, Sohal SS, Myers S. Targeting the Zinc Transporter ZIP7 in the Treatment of Insulin Resistance and Type 2 Diabetes. Nutrients 2019; 11:nu11020408. [PMID: 30781350 PMCID: PMC6412268 DOI: 10.3390/nu11020408] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 01/13/2019] [Accepted: 02/12/2019] [Indexed: 02/07/2023] Open
Abstract
Type 2 diabetes mellitus (T2DM) is a disease associated with dysfunctional metabolic processes that lead to abnormally high levels of blood glucose. Preceding the development of T2DM is insulin resistance (IR), a disorder associated with suppressed or delayed responses to insulin. The effects of this response are predominately mediated through aberrant cell signalling processes and compromised glucose uptake into peripheral tissue including adipose, liver and skeletal muscle. Moreover, a major factor considered to be the cause of IR is endoplasmic reticulum (ER) stress. This subcellular organelle plays a pivotal role in protein folding and processes that increase ER stress, leads to maladaptive responses that result in cell death. Recently, zinc and the proteins that transport this metal ion have been implicated in the ER stress response. Specifically, the ER-specific zinc transporter ZIP7, coined the "gate-keeper" of zinc release from the ER into the cytosol, was shown to be essential for maintaining ER homeostasis in intestinal epithelium and myeloid leukaemia cells. Moreover, ZIP7 controls essential cell signalling pathways similar to insulin and activates glucose uptake in skeletal muscle. Accordingly, ZIP7 may be essential for the control of ER localized zinc and mechanisms that disrupt this process may lead to ER-stress and contribute to IR. Accordingly, understanding the mechanisms of ZIP7 action in the context of IR may provide opportunities to develop novel therapeutic options to target this transporter in the treatment of IR and subsequent T2DM.
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Affiliation(s)
- John Adulcikas
- College of Health and Medicine, School of Health Sciences, University of Tasmania, TAS 7005, Australia.
| | - Sabrina Sonda
- College of Health and Medicine, School of Health Sciences, University of Tasmania, TAS 7005, Australia.
| | - Shaghayegh Norouzi
- College of Health and Medicine, School of Health Sciences, University of Tasmania, TAS 7005, Australia.
| | - Sukhwinder Singh Sohal
- College of Health and Medicine, School of Health Sciences, University of Tasmania, TAS 7005, Australia.
| | - Stephen Myers
- College of Health and Medicine, School of Health Sciences, University of Tasmania, TAS 7005, Australia.
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13
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Li H, Zhang J, Niswander L. Zinc deficiency causes neural tube defects through attenuation of p53 ubiquitylation. Development 2018; 145:145/24/dev169797. [PMID: 30545932 DOI: 10.1242/dev.169797] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 11/15/2018] [Indexed: 12/15/2022]
Abstract
Micronutrition is essential for neural tube closure, and zinc deficiency is associated with human neural tube defects. Here, we modeled zinc deficiency in mouse embryos, and used live imaging and molecular studies to determine how zinc deficiency affects neural tube closure. Embryos cultured with the zinc chelator TPEN failed to close the neural tube and showed excess apoptosis. TPEN-induced p53 protein stabilization in vivo and in neuroepithelial cell cultures and apoptosis was dependent on p53. Mechanistically, zinc deficiency resulted in disrupted interaction between p53 and the zinc-dependent E3 ubiquitin ligase Mdm2, and greatly reduced p53 ubiquitylation. Overexpression of human CHIP, a zinc-independent E3 ubiquitin ligase that targets p53, relieved TPEN-induced p53 stabilization and reduced apoptosis. Expression of p53 pro-apoptotic target genes was upregulated by zinc deficiency. Correspondingly, embryos cultured with p53 transcriptional activity inhibitor pifithrin-α could overcome TPEN-induced apoptosis and failure of neural tube closure. Our studies indicate that zinc deficiency disrupts neural tube closure through decreased p53 ubiquitylation, increased p53 stabilization and excess apoptosis.
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Affiliation(s)
- Huili Li
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Children's Hospital Colorado, Aurora, CO 80045, USA.,Department of Molecular, Cellular and Development Biology, University of Colorado Boulder, Boulder, CO 80309, USA
| | - Jing Zhang
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Children's Hospital Colorado, Aurora, CO 80045, USA.,Department of Molecular, Cellular and Development Biology, University of Colorado Boulder, Boulder, CO 80309, USA
| | - Lee Niswander
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Children's Hospital Colorado, Aurora, CO 80045, USA .,Department of Molecular, Cellular and Development Biology, University of Colorado Boulder, Boulder, CO 80309, USA
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14
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Luwang JW, Natesh R. Phosphomimetic Mutation Destabilizes the Central Core Domain of Human p53. IUBMB Life 2018; 70:1023-1031. [DOI: 10.1002/iub.1914] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Revised: 06/07/2018] [Accepted: 06/12/2018] [Indexed: 01/07/2023]
Affiliation(s)
- Johnson Wahengbam Luwang
- School of Biology; Indian Institute of Science Education and Research Thiruvananthapuram; Thiruvananthapuram-695551 Kerala India
| | - Ramanathan Natesh
- School of Biology; Indian Institute of Science Education and Research Thiruvananthapuram; Thiruvananthapuram-695551 Kerala India
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15
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Hacohen N, Ip CJX, Gordon R. Analysis of Egg White Protein Composition with Double Nanohole Optical Tweezers. ACS OMEGA 2018; 3:5266-5272. [PMID: 31458737 PMCID: PMC6641915 DOI: 10.1021/acsomega.8b00651] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 05/03/2018] [Indexed: 05/21/2023]
Abstract
We use a double nanohole optical tweezer to analyze the protein composition of egg white through analysis of many individual protein trapping events. The proteins are grouped by mass based on two metrics: standard deviation of the trapping laser intensity fluctuations from the protein diffusion and the time constant of these fluctuations coming from the autocorrelation. Quantitative analysis is demonstrated for artificial samples, and then, the approach is applied to real egg white. The composition found from real egg white corresponds well to past reports using gel electrophoresis. This approach differs from past works by allowing for individual protein analysis in heterogeneous solutions without the need for denaturing, labeling, or tethering.
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16
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Morita A, Takahashi I, Sasatani M, Aoki S, Wang B, Ariyasu S, Tanaka K, Yamaguchi T, Sawa A, Nishi Y, Teraoka T, Ujita S, Kawate Y, Yanagawa C, Tanimoto K, Enomoto A, Nenoi M, Kamiya K, Nagata Y, Hosoi Y, Inaba T. A Chemical Modulator of p53 Transactivation that Acts as a Radioprotective Agonist. Mol Cancer Ther 2017; 17:432-442. [PMID: 28939557 DOI: 10.1158/1535-7163.mct-16-0554] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 05/22/2017] [Accepted: 08/23/2017] [Indexed: 11/16/2022]
Abstract
Inhibiting p53-dependent apoptosis by inhibitors of p53 is an effective strategy for preventing radiation-induced damage in hematopoietic lineages, while p53 and p21 also play radioprotective roles in the gastrointestinal epithelium. We previously identified some zinc(II) chelators, including 8-quinolinol derivatives, that suppress apoptosis in attempts to discover compounds that target the zinc-binding site in p53. We found that 5-chloro-8-quinolinol (5CHQ) has a unique p53-modulating activity that shifts its transactivation from proapoptotic to protective responses, including enhancing p21 induction and suppressing PUMA induction. This p53-modulating activity also influenced p53 and p53-target gene expression in unirradiated cells without inducing DNA damage. The specificity of 5CHQ for p53 and p21 was demonstrated by silencing the expression of each protein. These effects seem to be attributable to the sequence-specific alteration of p53 DNA-binding, as evaluated by chromatin immunoprecipitation and electrophoretic mobility shift assays. In addition, 5-chloro-8-methoxyquinoline itself had no antiapoptotic activity, indicating that the hydroxyl group at the 8-position is required for its antiapoptotic activity. We applied this remarkable agonistic activity to protecting the hematopoietic and gastrointestinal system in mouse irradiation models. The dose reduction factors of 5CHQ in total-body and abdominally irradiated mice were about 1.2 and 1.3, respectively. 5CHQ effectively protected mouse epithelial stem cells from a lethal dose of abdominal irradiation. Furthermore, the specificity of 5CHQ for p53 in reducing the lethality induced by abdominal irradiation was revealed in Trp53-KO mice. These results indicate that the pharmacologic upregulation of radioprotective p53 target genes is an effective strategy for addressing the gastrointestinal syndrome. Mol Cancer Ther; 17(2); 432-42. ©2017 AACRSee all articles in this MCT Focus section, "Developmental Therapeutics in Radiation Oncology."
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Affiliation(s)
- Akinori Morita
- Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan. .,Department of Biomedical Science and Technology, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Ippei Takahashi
- Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan.,Department of Radiation Oncology, Hiroshima University, Hiroshima, Japan
| | - Megumi Sasatani
- Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
| | - Shin Aoki
- Department of Medicinal and Life Science, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Chiba, Japan.,Center for Technologies against Cancer, Tokyo University of Science, Chiba, Japan
| | - Bing Wang
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Shinya Ariyasu
- Center for Technologies against Cancer, Tokyo University of Science, Chiba, Japan
| | - Kaoru Tanaka
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Tetsuji Yamaguchi
- Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
| | - Akiko Sawa
- Department of Medicinal and Life Science, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Chiba, Japan
| | - Yurie Nishi
- Department of Medicinal and Life Science, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Chiba, Japan
| | - Tatsuro Teraoka
- Department of Medicinal and Life Science, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Chiba, Japan
| | - Shohei Ujita
- Department of Biomedical Science and Technology, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Yosuke Kawate
- Department of Biomedical Science and Technology, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Chihiro Yanagawa
- Department of Biomedical Science and Technology, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan
| | - Keiji Tanimoto
- Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
| | - Atsushi Enomoto
- Laboratory of Molecular Radiology, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Mitsuru Nenoi
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Kenji Kamiya
- Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
| | - Yasushi Nagata
- Department of Radiation Oncology, Hiroshima University, Hiroshima, Japan
| | - Yoshio Hosoi
- Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan.,Department of Radiation Biology, Graduate School of Medicine, Tohoku University, Sendai, Japan
| | - Toshiya Inaba
- Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
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17
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Jabrani A, Makamte S, Moreau E, Gharbi Y, Plessis A, Bruzzone L, Sanial M, Biou V. Biophysical characterisation of the novel zinc binding property in Suppressor of Fused. Sci Rep 2017; 7:11139. [PMID: 28894158 PMCID: PMC5593987 DOI: 10.1038/s41598-017-11203-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 08/21/2017] [Indexed: 01/09/2023] Open
Abstract
Suppressor of Fused (SUFU) is a highly conserved protein that acts as a negative regulator of the Hedgehog (HH) signalling pathway, a major determinant of cell differentiation and proliferation. Therefore, SUFU deletion in mammals has devastating effects on embryo development. SUFU is part of a multi-protein cytoplasmic signal-transducing complex. Its partners include the Gli family of transcription factors that function either as repressors, or as transcription activators according to the HH activation state. The crystal structure of SUFU revealed a two-domain arrangement, which undergoes a closing movement upon binding a peptide from Gli1. There remains however, much to be discovered about SUFU’s behaviour. To this end, we expressed recombinant, full-length SUFU from Drosophila, Zebrafish and Human. Guided by a sequence analysis that revealed a conserved potential metal binding site, we discovered that SUFU binds zinc. This binding was found to occur with a nanomolar affinity to SUFU from all three species. Mutation of one histidine from the conserved motif induces a moderate decrease in affinity for zinc, while circular dichroism indicates that the mutant remains structured. Our results reveal new metal binding affinity characteristics about SUFU that could be of importance for its regulatory function in HH.
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Affiliation(s)
- Amira Jabrani
- Laboratoire de Biologie Physico-Chimique des Protéines Membranaires, UMR 7099 CNRS, Université Paris Diderot, Sorbonne Paris Cité, PSL Research University, Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005, Paris, France
| | - Staëlle Makamte
- Laboratoire de Biologie Physico-Chimique des Protéines Membranaires, UMR 7099 CNRS, Université Paris Diderot, Sorbonne Paris Cité, PSL Research University, Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005, Paris, France
| | - Emilie Moreau
- Laboratoire de Biologie Physico-Chimique des Protéines Membranaires, UMR 7099 CNRS, Université Paris Diderot, Sorbonne Paris Cité, PSL Research University, Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005, Paris, France
| | - Yasmine Gharbi
- Laboratoire de Biologie Physico-Chimique des Protéines Membranaires, UMR 7099 CNRS, Université Paris Diderot, Sorbonne Paris Cité, PSL Research University, Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005, Paris, France
| | - Anne Plessis
- Institut Jacques Monod UMR 7592, CNRS, Université Paris Diderot, Sorbonne Paris Cité, F-75205, Paris, France
| | - Lucia Bruzzone
- Institut Jacques Monod UMR 7592, CNRS, Université Paris Diderot, Sorbonne Paris Cité, F-75205, Paris, France
| | - Matthieu Sanial
- Institut Jacques Monod UMR 7592, CNRS, Université Paris Diderot, Sorbonne Paris Cité, F-75205, Paris, France
| | - Valérie Biou
- Laboratoire de Biologie Physico-Chimique des Protéines Membranaires, UMR 7099 CNRS, Université Paris Diderot, Sorbonne Paris Cité, PSL Research University, Institut de Biologie Physico-Chimique, 13 rue Pierre et Marie Curie, 75005, Paris, France.
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18
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19
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Yu X, Blanden A, Tsang AT, Zaman S, Liu Y, Gilleran J, Bencivenga AF, Kimball SD, Loh SN, Carpizo DR. Thiosemicarbazones Functioning as Zinc Metallochaperones to Reactivate Mutant p53. Mol Pharmacol 2017; 91:567-575. [PMID: 28320780 DOI: 10.1124/mol.116.107409] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Accepted: 03/16/2017] [Indexed: 12/21/2022] Open
Abstract
Small-molecule restoration of wild-type structure and function to mutant p53 (so-called mutant reactivation) is a highly sought-after goal in cancer drug development. We previously discovered that small-molecule zinc chelators called zinc metallochaperones (ZMCs) reactivate mutant p53 by restoring zinc binding to zinc-deficient p53 mutants. The lead compound identified from the NCI-60 human tumor cell lines screen, NSC319726 (ZMC1), belongs to the thiosemicarbazone (TSC) class of metal ion chelators that bind iron, copper, magnesium, zinc, and other transition metals. Here, we have investigated the other TSCs, NSC319725 and NSC328784, identified in the same screen, as well as the more well studied TSC, 3-AP (Triapine), to determine whether they function as ZMCs. We measured the zinc Kd zinc ionophore activity, ability to restore zinc to purified p53 DNA binding domain (DBD), and ability to restore site-specific DNA binding to purified R175H-DBD in vitro. We tested all four TSCs in a number of cell-based assays to examine mutant p53 reactivation and the generation of reactive oxygen species (ROS). We found that NSC319725 and NSC328784 behave similarly to ZMC1 in both biophysical and cell-based assays and are heretofore named ZMC2 (NSC319725) and ZMC3 (NSC328784). 3-AP generates a ROS signal similar to ZMC1-3, but it fails to function as a ZMC both in vitro and in cells and ultimately does not reactivate p53. These findings indicate that not all TSCs function as ZMCs, and much of their activity can be predicted by their affinity for zinc.
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Affiliation(s)
- Xin Yu
- Rutgers Cancer Institute of New Jersey (X.Y., A.T.T., S.Z., Y.L., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., A.T.T, Y.L., D.R.C.), Rutgers Translational Sciences, Department of Chemistry and Chemical Biology (S.D.K.), Department of Medicinal Chemistry, Rutgers Ernest Mario School of Pharmacy (J.G., A.F.B., S.D.K.), Rutgers University, New Brunswick, New Jersey; Department of Biochemistry and Molecular Biology, State University of New York (SUNY) Upstate Medical University, Syracuse, New York (A.B., S.N.L.); and Mount Sinai St. Luke's Roosevelt General Surgery Residency Program, New York, New York (A.T.T.)
| | - Adam Blanden
- Rutgers Cancer Institute of New Jersey (X.Y., A.T.T., S.Z., Y.L., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., A.T.T, Y.L., D.R.C.), Rutgers Translational Sciences, Department of Chemistry and Chemical Biology (S.D.K.), Department of Medicinal Chemistry, Rutgers Ernest Mario School of Pharmacy (J.G., A.F.B., S.D.K.), Rutgers University, New Brunswick, New Jersey; Department of Biochemistry and Molecular Biology, State University of New York (SUNY) Upstate Medical University, Syracuse, New York (A.B., S.N.L.); and Mount Sinai St. Luke's Roosevelt General Surgery Residency Program, New York, New York (A.T.T.)
| | - Ashley T Tsang
- Rutgers Cancer Institute of New Jersey (X.Y., A.T.T., S.Z., Y.L., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., A.T.T, Y.L., D.R.C.), Rutgers Translational Sciences, Department of Chemistry and Chemical Biology (S.D.K.), Department of Medicinal Chemistry, Rutgers Ernest Mario School of Pharmacy (J.G., A.F.B., S.D.K.), Rutgers University, New Brunswick, New Jersey; Department of Biochemistry and Molecular Biology, State University of New York (SUNY) Upstate Medical University, Syracuse, New York (A.B., S.N.L.); and Mount Sinai St. Luke's Roosevelt General Surgery Residency Program, New York, New York (A.T.T.)
| | - Saif Zaman
- Rutgers Cancer Institute of New Jersey (X.Y., A.T.T., S.Z., Y.L., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., A.T.T, Y.L., D.R.C.), Rutgers Translational Sciences, Department of Chemistry and Chemical Biology (S.D.K.), Department of Medicinal Chemistry, Rutgers Ernest Mario School of Pharmacy (J.G., A.F.B., S.D.K.), Rutgers University, New Brunswick, New Jersey; Department of Biochemistry and Molecular Biology, State University of New York (SUNY) Upstate Medical University, Syracuse, New York (A.B., S.N.L.); and Mount Sinai St. Luke's Roosevelt General Surgery Residency Program, New York, New York (A.T.T.)
| | - Yue Liu
- Rutgers Cancer Institute of New Jersey (X.Y., A.T.T., S.Z., Y.L., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., A.T.T, Y.L., D.R.C.), Rutgers Translational Sciences, Department of Chemistry and Chemical Biology (S.D.K.), Department of Medicinal Chemistry, Rutgers Ernest Mario School of Pharmacy (J.G., A.F.B., S.D.K.), Rutgers University, New Brunswick, New Jersey; Department of Biochemistry and Molecular Biology, State University of New York (SUNY) Upstate Medical University, Syracuse, New York (A.B., S.N.L.); and Mount Sinai St. Luke's Roosevelt General Surgery Residency Program, New York, New York (A.T.T.)
| | - John Gilleran
- Rutgers Cancer Institute of New Jersey (X.Y., A.T.T., S.Z., Y.L., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., A.T.T, Y.L., D.R.C.), Rutgers Translational Sciences, Department of Chemistry and Chemical Biology (S.D.K.), Department of Medicinal Chemistry, Rutgers Ernest Mario School of Pharmacy (J.G., A.F.B., S.D.K.), Rutgers University, New Brunswick, New Jersey; Department of Biochemistry and Molecular Biology, State University of New York (SUNY) Upstate Medical University, Syracuse, New York (A.B., S.N.L.); and Mount Sinai St. Luke's Roosevelt General Surgery Residency Program, New York, New York (A.T.T.)
| | - Anthony F Bencivenga
- Rutgers Cancer Institute of New Jersey (X.Y., A.T.T., S.Z., Y.L., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., A.T.T, Y.L., D.R.C.), Rutgers Translational Sciences, Department of Chemistry and Chemical Biology (S.D.K.), Department of Medicinal Chemistry, Rutgers Ernest Mario School of Pharmacy (J.G., A.F.B., S.D.K.), Rutgers University, New Brunswick, New Jersey; Department of Biochemistry and Molecular Biology, State University of New York (SUNY) Upstate Medical University, Syracuse, New York (A.B., S.N.L.); and Mount Sinai St. Luke's Roosevelt General Surgery Residency Program, New York, New York (A.T.T.)
| | - S David Kimball
- Rutgers Cancer Institute of New Jersey (X.Y., A.T.T., S.Z., Y.L., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., A.T.T, Y.L., D.R.C.), Rutgers Translational Sciences, Department of Chemistry and Chemical Biology (S.D.K.), Department of Medicinal Chemistry, Rutgers Ernest Mario School of Pharmacy (J.G., A.F.B., S.D.K.), Rutgers University, New Brunswick, New Jersey; Department of Biochemistry and Molecular Biology, State University of New York (SUNY) Upstate Medical University, Syracuse, New York (A.B., S.N.L.); and Mount Sinai St. Luke's Roosevelt General Surgery Residency Program, New York, New York (A.T.T.)
| | - Stewart N Loh
- Rutgers Cancer Institute of New Jersey (X.Y., A.T.T., S.Z., Y.L., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., A.T.T, Y.L., D.R.C.), Rutgers Translational Sciences, Department of Chemistry and Chemical Biology (S.D.K.), Department of Medicinal Chemistry, Rutgers Ernest Mario School of Pharmacy (J.G., A.F.B., S.D.K.), Rutgers University, New Brunswick, New Jersey; Department of Biochemistry and Molecular Biology, State University of New York (SUNY) Upstate Medical University, Syracuse, New York (A.B., S.N.L.); and Mount Sinai St. Luke's Roosevelt General Surgery Residency Program, New York, New York (A.T.T.)
| | - Darren R Carpizo
- Rutgers Cancer Institute of New Jersey (X.Y., A.T.T., S.Z., Y.L., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., A.T.T, Y.L., D.R.C.), Rutgers Translational Sciences, Department of Chemistry and Chemical Biology (S.D.K.), Department of Medicinal Chemistry, Rutgers Ernest Mario School of Pharmacy (J.G., A.F.B., S.D.K.), Rutgers University, New Brunswick, New Jersey; Department of Biochemistry and Molecular Biology, State University of New York (SUNY) Upstate Medical University, Syracuse, New York (A.B., S.N.L.); and Mount Sinai St. Luke's Roosevelt General Surgery Residency Program, New York, New York (A.T.T.)
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20
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Thayer KM, Quinn TR. p53 R175H hydrophobic patch and H-bond reorganization observed by MD simulation. Biopolymers 2016; 105:176-85. [PMID: 26566695 DOI: 10.1002/bip.22766] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 11/06/2015] [Accepted: 11/10/2015] [Indexed: 01/28/2023]
Abstract
Molecular dynamics simulations probe the origins of aberrant functionality of R175H p53, which normally prevent tumorigenesis. This hotspot mutation exhibits loss of its essential zinc cofactor, aggregation, and activation of gain of function promoters, characteristics contributing to the loss of normal p53 activity. This study provided molecular level insight into the reorganization of the hydrogen bonding network and the formation of a hydrophobic patch on the surface of the protein. The hydrogen bonding network globally redistributes at the expense of the stability of the β-sandwich structure, and surface residues reorganize to expose a 250 Å(2) hydrophobic patch of residues covering approximately 2% of the solvent accessible surface. These changes could both stabilize the protein in the conformation exposing the patch to solvent to mediate the reported aggregation, and cause a destabilization in the area associated with DNA binding residues to affect the specificity. The development of the patch prior to loss of zinc indicates that stabilizing the patch quickly may prevent zinc loss. Considerations for rational design of small molecule therapeutics in light of the structural insight has been discussed and it suggest the positive ring around the hydrophobic patch and conserved residues may constitute a druggable site.
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Affiliation(s)
- Kelly M Thayer
- Department of Chemistry, Vassar College, 124 Raymond Ave, Poughkeepsie, NY, 12604.,Department of Chemistry, Hall-Atwater Laboratories, Wesleyan University, Middletown, CT, 06459
| | - Taylor R Quinn
- Department of Chemistry, Vassar College, 124 Raymond Ave, Poughkeepsie, NY, 12604.,Department of Chemistry, University of Notre Dame, Notre Dame, IN, 46556
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21
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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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22
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Dissecting protein architecture with communication blocks and communicating segment pairs. BMC Bioinformatics 2016; 17 Suppl 2:13. [PMID: 26823083 PMCID: PMC4959365 DOI: 10.1186/s12859-015-0855-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Proteins adapt to environmental conditions by changing their shape and motions. Characterising protein conformational dynamics is increasingly recognised as necessary to understand how proteins function. Given a conformational ensemble, computational tools are needed to extract in a systematic way pertinent and comprehensive biological information. RESULTS Here, we present a method, Communication Mapping (COMMA), to decipher the dynamical architecture of a protein. The method first extracts residue-based dynamic properties from all-atom molecular dynamics simulations. Then, it integrates them in a graph theoretic framework, where it identifies groups of residues or protein regions that mediate short- and long-range communication. COMMA introduces original concepts to contrast the different roles played by these regions, namely communication blocks and communicating segment pairs, and evaluates the connections and communication strengths between them. We show the utility and capabilities of COMMA by applying it to three archetypal proteins, namely protein A, the tyrosine kinase KIT and the tumour suppressor p53. CONCLUSION Our method permits to compare in a direct way the dynamical behaviour either of proteins with different characteristics or of the same protein in different conditions. It is useful to identify residues playing a key role in protein allosteric regulation and to explain the effects of deleterious mutations in a mechanistic way. COMMA is a fully automated tool with broad applicability. It is freely available to the community at www.lcqb.upmc.fr/COMMA .
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23
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Improved cytotoxicity of pyridyl-substituted thiosemicarbazones against MCF-7 when used as metal ionophores. Biometals 2015; 29:157-70. [DOI: 10.1007/s10534-015-9905-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 12/10/2015] [Indexed: 01/06/2023]
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Yu X, Blanden AR, Narayanan S, Jayakumar L, Lubin D, Augeri D, Kimball SD, Loh SN, Carpizo DR. Small molecule restoration of wildtype structure and function of mutant p53 using a novel zinc-metallochaperone based mechanism. Oncotarget 2015; 5:8879-92. [PMID: 25294809 PMCID: PMC4253404 DOI: 10.18632/oncotarget.2432] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
NSC319726 (ZMC1) is a small molecule that reactivates mutant p53 by restoration of WT structure/function to the most common p53 missense mutant (p53-R175H). We investigated the mechanism by which ZMC1 reactivates p53-R175H and provide evidence that ZMC1: 1) restores WT structure by functioning as a zinc-metallochaperone, providing an optimal concentration of zinc to facilitate proper folding; and 2) increases cellular reactive oxygen species that transactivate the newly conformed p53-R175H (via post-translational modifications), inducing an apoptotic program. We not only demonstrate that this zinc metallochaperone function is possessed by other zinc-binding small molecules, but that it can reactivate other p53 mutants with impaired zinc binding. This represents a novel mechanism for an anti-cancer drug and a new pathway to drug mutant p53. Significance: We have elucidated a novel mechanism to restore wild-type structure/function to mutant p53 using small molecules functioning as zinc-metallochaperones. The pharmacologic delivery of a metal ion to restore proper folding of a mutant protein is unique to medicinal chemistry and represents a new pathway to drug mutant p53.
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Affiliation(s)
- Xin Yu
- Rutgers Cancer Institute of New Jersey, New Jersey. Department of Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, New Jersey. These authors contributed equally to this work
| | - Adam R Blanden
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, New York. These authors contributed equally to this work
| | - Sumana Narayanan
- Department of Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, New Jersey
| | - Lalithapriya Jayakumar
- Department of Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, New Jersey
| | - David Lubin
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, New York
| | - David Augeri
- Department of Medicinal Chemistry, Rutgers Ernest Mario School of Pharmacy, Piscataway, New Jersey
| | - S David Kimball
- Department of Medicinal Chemistry, Rutgers Ernest Mario School of Pharmacy, Piscataway, New Jersey
| | - Stewart N Loh
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, New York
| | - Darren R Carpizo
- Rutgers Cancer Institute of New Jersey, New Jersey. Department of Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, New Jersey
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25
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Reactivating mutant p53 using small molecules as zinc metallochaperones: awakening a sleeping giant in cancer. Drug Discov Today 2015. [PMID: 26205328 DOI: 10.1016/j.drudis.2015.07.006] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Tumor protein p53 (TP53) is the most commonly mutated gene in human cancer. The majority of mutations are missense, and generate a defective protein that is druggable. Yet, for decades, the small-molecule restoration of wild-type (WT) p53 function in mutant p53 tumors (so-called p53 mutant 'reactivation') has been elusive to researchers. The p53 protein requires the binding of a single zinc ion for proper folding, and impairing zinc binding is a major mechanism for loss of function in missense mutant p53. Here, we describe recent work defining a new class of drugs termed zinc metallochaperones that restore WT p53 structure and function by restoring Zn(2+) to Zn(2+)-deficient mutant p53.
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Blanden AR, Yu X, Wolfe AJ, Gilleran JA, Augeri DJ, O'Dell RS, Olson EC, Kimball SD, Emge TJ, Movileanu L, Carpizo DR, Loh SN. Synthetic metallochaperone ZMC1 rescues mutant p53 conformation by transporting zinc into cells as an ionophore. Mol Pharmacol 2015; 87:825-31. [PMID: 25710967 DOI: 10.1124/mol.114.097550] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
p53 is a Zn(2+)-dependent tumor suppressor inactivated in >50% of human cancers. The most common mutation, R175H, inactivates p53 by reducing its affinity for the essential zinc ion, leaving the mutant protein unable to bind the metal in the low [Zn(2+)]free environment of the cell. The exploratory cancer drug zinc metallochaperone-1 (ZMC1) was previously demonstrated to reactivate this and other Zn(2+)-binding mutants by binding Zn(2+) and buffering it to a level such that Zn(2+) can repopulate the defective binding site, but how it accomplishes this in the context of living cells and organisms is unclear. In this study, we demonstrated that ZMC1 increases intracellular [Zn(2+)]free by functioning as a Zn(2+) ionophore, binding Zn(2+) in the extracellular environment, diffusing across the plasma membrane, and releasing it intracellularly. It raises intracellular [Zn(2+)]free in cancer (TOV112D) and noncancer human embryonic kidney cell line 293 to 15.8 and 18.1 nM, respectively, with half-times of 2-3 minutes. These [Zn(2+)]free levels are predicted to result in ∼90% saturation of p53-R175H, thus accounting for its observed reactivation. This mechanism is supported by the X-ray crystal structure of the [Zn(ZMC1)2] complex, which demonstrates structural and chemical features consistent with those of known metal ionophores. These findings provide a physical mechanism linking zinc metallochaperone-1 in both in vitro and in vivo activities and define the remaining critical parameter necessary for developing synthetic metallochaperones for clinical use.
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Affiliation(s)
- Adam R Blanden
- Department of Biochemistry and Molecular Biology (A.R.B.,S.N.L.) and Department of Neuroscience and Physiology (R.S.O., E.C.O.), State University of New York Upstate Medical University, Syracuse, New York; Rutgers Cancer Institute of New Jersey (X.Y., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., D.R.C.), Office of Translational Sciences (J.A.G., D.J.A., S.D.K.), and Department of Chemistry and Chemical Biology (T.J.E.), Rutgers University, New Brunswick, New Jersey; and Department of Physics, Syracuse University, Syracuse, New York (A.J.W., L.M.)
| | - Xin Yu
- Department of Biochemistry and Molecular Biology (A.R.B.,S.N.L.) and Department of Neuroscience and Physiology (R.S.O., E.C.O.), State University of New York Upstate Medical University, Syracuse, New York; Rutgers Cancer Institute of New Jersey (X.Y., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., D.R.C.), Office of Translational Sciences (J.A.G., D.J.A., S.D.K.), and Department of Chemistry and Chemical Biology (T.J.E.), Rutgers University, New Brunswick, New Jersey; and Department of Physics, Syracuse University, Syracuse, New York (A.J.W., L.M.)
| | - Aaron J Wolfe
- Department of Biochemistry and Molecular Biology (A.R.B.,S.N.L.) and Department of Neuroscience and Physiology (R.S.O., E.C.O.), State University of New York Upstate Medical University, Syracuse, New York; Rutgers Cancer Institute of New Jersey (X.Y., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., D.R.C.), Office of Translational Sciences (J.A.G., D.J.A., S.D.K.), and Department of Chemistry and Chemical Biology (T.J.E.), Rutgers University, New Brunswick, New Jersey; and Department of Physics, Syracuse University, Syracuse, New York (A.J.W., L.M.)
| | - John A Gilleran
- Department of Biochemistry and Molecular Biology (A.R.B.,S.N.L.) and Department of Neuroscience and Physiology (R.S.O., E.C.O.), State University of New York Upstate Medical University, Syracuse, New York; Rutgers Cancer Institute of New Jersey (X.Y., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., D.R.C.), Office of Translational Sciences (J.A.G., D.J.A., S.D.K.), and Department of Chemistry and Chemical Biology (T.J.E.), Rutgers University, New Brunswick, New Jersey; and Department of Physics, Syracuse University, Syracuse, New York (A.J.W., L.M.)
| | - David J Augeri
- Department of Biochemistry and Molecular Biology (A.R.B.,S.N.L.) and Department of Neuroscience and Physiology (R.S.O., E.C.O.), State University of New York Upstate Medical University, Syracuse, New York; Rutgers Cancer Institute of New Jersey (X.Y., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., D.R.C.), Office of Translational Sciences (J.A.G., D.J.A., S.D.K.), and Department of Chemistry and Chemical Biology (T.J.E.), Rutgers University, New Brunswick, New Jersey; and Department of Physics, Syracuse University, Syracuse, New York (A.J.W., L.M.)
| | - Ryan S O'Dell
- Department of Biochemistry and Molecular Biology (A.R.B.,S.N.L.) and Department of Neuroscience and Physiology (R.S.O., E.C.O.), State University of New York Upstate Medical University, Syracuse, New York; Rutgers Cancer Institute of New Jersey (X.Y., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., D.R.C.), Office of Translational Sciences (J.A.G., D.J.A., S.D.K.), and Department of Chemistry and Chemical Biology (T.J.E.), Rutgers University, New Brunswick, New Jersey; and Department of Physics, Syracuse University, Syracuse, New York (A.J.W., L.M.)
| | - Eric C Olson
- Department of Biochemistry and Molecular Biology (A.R.B.,S.N.L.) and Department of Neuroscience and Physiology (R.S.O., E.C.O.), State University of New York Upstate Medical University, Syracuse, New York; Rutgers Cancer Institute of New Jersey (X.Y., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., D.R.C.), Office of Translational Sciences (J.A.G., D.J.A., S.D.K.), and Department of Chemistry and Chemical Biology (T.J.E.), Rutgers University, New Brunswick, New Jersey; and Department of Physics, Syracuse University, Syracuse, New York (A.J.W., L.M.)
| | - S David Kimball
- Department of Biochemistry and Molecular Biology (A.R.B.,S.N.L.) and Department of Neuroscience and Physiology (R.S.O., E.C.O.), State University of New York Upstate Medical University, Syracuse, New York; Rutgers Cancer Institute of New Jersey (X.Y., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., D.R.C.), Office of Translational Sciences (J.A.G., D.J.A., S.D.K.), and Department of Chemistry and Chemical Biology (T.J.E.), Rutgers University, New Brunswick, New Jersey; and Department of Physics, Syracuse University, Syracuse, New York (A.J.W., L.M.)
| | - Thomas J Emge
- Department of Biochemistry and Molecular Biology (A.R.B.,S.N.L.) and Department of Neuroscience and Physiology (R.S.O., E.C.O.), State University of New York Upstate Medical University, Syracuse, New York; Rutgers Cancer Institute of New Jersey (X.Y., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., D.R.C.), Office of Translational Sciences (J.A.G., D.J.A., S.D.K.), and Department of Chemistry and Chemical Biology (T.J.E.), Rutgers University, New Brunswick, New Jersey; and Department of Physics, Syracuse University, Syracuse, New York (A.J.W., L.M.)
| | - Liviu Movileanu
- Department of Biochemistry and Molecular Biology (A.R.B.,S.N.L.) and Department of Neuroscience and Physiology (R.S.O., E.C.O.), State University of New York Upstate Medical University, Syracuse, New York; Rutgers Cancer Institute of New Jersey (X.Y., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., D.R.C.), Office of Translational Sciences (J.A.G., D.J.A., S.D.K.), and Department of Chemistry and Chemical Biology (T.J.E.), Rutgers University, New Brunswick, New Jersey; and Department of Physics, Syracuse University, Syracuse, New York (A.J.W., L.M.)
| | - Darren R Carpizo
- Department of Biochemistry and Molecular Biology (A.R.B.,S.N.L.) and Department of Neuroscience and Physiology (R.S.O., E.C.O.), State University of New York Upstate Medical University, Syracuse, New York; Rutgers Cancer Institute of New Jersey (X.Y., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., D.R.C.), Office of Translational Sciences (J.A.G., D.J.A., S.D.K.), and Department of Chemistry and Chemical Biology (T.J.E.), Rutgers University, New Brunswick, New Jersey; and Department of Physics, Syracuse University, Syracuse, New York (A.J.W., L.M.)
| | - Stewart N Loh
- Department of Biochemistry and Molecular Biology (A.R.B.,S.N.L.) and Department of Neuroscience and Physiology (R.S.O., E.C.O.), State University of New York Upstate Medical University, Syracuse, New York; Rutgers Cancer Institute of New Jersey (X.Y., D.R.C.), Department of Surgery, Rutgers Robert Wood Johnson Medical School (X.Y., D.R.C.), Office of Translational Sciences (J.A.G., D.J.A., S.D.K.), and Department of Chemistry and Chemical Biology (T.J.E.), Rutgers University, New Brunswick, New Jersey; and Department of Physics, Syracuse University, Syracuse, New York (A.J.W., L.M.)
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27
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Phatak VM, Muller PAJ. Metal toxicity and the p53 protein: an intimate relationship. Toxicol Res (Camb) 2015. [DOI: 10.1039/c4tx00117f] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The relationship between p53, ROS and transition metals.
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Eldar A, Rozenberg H, Diskin-Posner Y, Rohs R, Shakked Z. Structural studies of p53 inactivation by DNA-contact mutations and its rescue by suppressor mutations via alternative protein-DNA interactions. Nucleic Acids Res 2013; 41:8748-59. [PMID: 23863845 PMCID: PMC3794590 DOI: 10.1093/nar/gkt630] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
A p53 hot-spot mutation found frequently in human cancer is the replacement of R273 by histidine or cysteine residues resulting in p53 loss of function as a tumor suppressor. These mutants can be reactivated by the incorporation of second-site suppressor mutations. Here, we present high-resolution crystal structures of the p53 core domains of the cancer-related proteins, the rescued proteins and their complexes with DNA. The structures show that inactivation of p53 results from the incapacity of the mutated residues to form stabilizing interactions with the DNA backbone, and that reactivation is achieved through alternative interactions formed by the suppressor mutations. Detailed structural and computational analysis demonstrates that the rescued p53 complexes are not fully restored in terms of DNA structure and its interface with p53. Contrary to our previously studied wild-type (wt) p53-DNA complexes showing non-canonical Hoogsteen A/T base pairs of the DNA helix that lead to local minor-groove narrowing and enhanced electrostatic interactions with p53, the current structures display Watson-Crick base pairs associated with direct or water-mediated hydrogen bonds with p53 at the minor groove. These findings highlight the pivotal role played by R273 residues in supporting the unique geometry of the DNA target and its sequence-specific complex with p53.
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Affiliation(s)
- Amir Eldar
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel and Molecular and Computational Biology Program, University of Southern California, Los Angeles, CA 90089, USA
| | - Haim Rozenberg
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel and Molecular and Computational Biology Program, University of Southern California, Los Angeles, CA 90089, USA
| | - Yael Diskin-Posner
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel and Molecular and Computational Biology Program, University of Southern California, Los Angeles, CA 90089, USA
| | - Remo Rohs
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel and Molecular and Computational Biology Program, University of Southern California, Los Angeles, CA 90089, USA
| | - Zippora Shakked
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel and Molecular and Computational Biology Program, University of Southern California, Los Angeles, CA 90089, USA,*To whom correspondence should be addressed. Tel: +972 8 934 2672; Fax: +972 8 934 6278;
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29
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Abstract
Rescuing the function of mutant p53 protein is an attractive cancer therapeutic strategy. Using the National Cancer Institute's anticancer drug screen data, we identified two compounds from the thiosemicarbazone family that manifest increased growth inhibitory activity in mutant p53 cells, particularly for the p53(R175) mutant. Mechanistic studies reveal that NSC319726 restores WT structure and function to the p53(R175) mutant. This compound kills p53(R172H) knockin mice with extensive apoptosis and inhibits xenograft tumor growth in a 175-allele-specific mutant p53-dependent manner. This activity depends upon the zinc ion chelating properties of the compound as well as redox changes. These data identify NSC319726 as a p53(R175) mutant reactivator and as a lead compound for p53-targeted drug development.
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30
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Yu X, Vazquez A, Levine AJ, Carpizo DR. Allele-specific p53 mutant reactivation. Cancer Cell 2012; 21:614-625. [PMID: 22624712 PMCID: PMC3366694 DOI: 10.1016/j.ccr.2012.03.042] [Citation(s) in RCA: 250] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Revised: 01/05/2012] [Accepted: 03/12/2012] [Indexed: 10/28/2022]
Abstract
Rescuing the function of mutant p53 protein is an attractive cancer therapeutic strategy. Using the National Cancer Institute's anticancer drug screen data, we identified two compounds from the thiosemicarbazone family that manifest increased growth inhibitory activity in mutant p53 cells, particularly for the p53(R175) mutant. Mechanistic studies reveal that NSC319726 restores WT structure and function to the p53(R175) mutant. This compound kills p53(R172H) knockin mice with extensive apoptosis and inhibits xenograft tumor growth in a 175-allele-specific mutant p53-dependent manner. This activity depends upon the zinc ion chelating properties of the compound as well as redox changes. These data identify NSC319726 as a p53(R175) mutant reactivator and as a lead compound for p53-targeted drug development.
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Affiliation(s)
- Xin Yu
- The Cancer Institute of New Jersey, New Brunswick, NJ 08903, USA; Division of Surgical Oncology, Department of Surgery, University of Medicine and Dentistry of New Jersey, New Brunswick, NJ 08903, USA
| | - Alexei Vazquez
- The Cancer Institute of New Jersey, New Brunswick, NJ 08903, USA; Institute for Advanced Study, Princeton, NJ 08540, USA; Department of Radiation Oncology and Center for Systems Biology, University of Medicine and Dentistry of New Jersey, New Brunswick, NJ 08903, USA
| | - Arnold J Levine
- The Cancer Institute of New Jersey, New Brunswick, NJ 08903, USA; Institute for Advanced Study, Princeton, NJ 08540, USA; Department of Pediatrics, University of Medicine and Dentistry of New Jersey, New Brunswick, NJ 08903, USA
| | - Darren R Carpizo
- The Cancer Institute of New Jersey, New Brunswick, NJ 08903, USA; Division of Surgical Oncology, Department of Surgery, University of Medicine and Dentistry of New Jersey, New Brunswick, NJ 08903, USA.
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31
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Maret W. New perspectives of zinc coordination environments in proteins. J Inorg Biochem 2011; 111:110-6. [PMID: 22196021 DOI: 10.1016/j.jinorgbio.2011.11.018] [Citation(s) in RCA: 124] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Revised: 10/21/2011] [Accepted: 11/08/2011] [Indexed: 11/24/2022]
Abstract
Zinc is more widely used as a cofactor in proteins than any other transition metal ion. In addition to catalytic and structural functions, zinc(II) ions have a role in information transfer and cellular control. They bind transiently when proteins regulate zinc concentrations and re-distribute zinc and when proteins are regulated by zinc. Transient zinc-binding sites employ the same donors of amino acid side chains as catalytic and structural sites but differ in their coordination chemistry that can modulate zinc affinities over at least ten orders of magnitude. Redox activity of the cysteine ligands, multiple binding modes of the oxygen, sulfur and nitrogen donors, and protein conformational changes induce coordination dynamics in zinc sites and zinc ion mobility. Functional annotations of the remarkable variation of coordination environments in zinc proteomes need to consider how the primary coordination spheres interact with protein structure and dynamics, and the adaptation of coordination properties to the biological context in extracellular, cellular, or subcellular locations.
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Affiliation(s)
- Wolfgang Maret
- Metal Metabolism Group, Diabetes and Nutritional Sciences Division, School of Medicine, King's College London, London, UK
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32
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Wang T, Shao X, Cai W, Xue Y, Wang S, Feng X. Predicting the coordination geometry for Mg2+ in the p53 DNA-binding domain: insights from computational studies. Phys Chem Chem Phys 2010; 13:1140-51. [PMID: 21076775 DOI: 10.1039/c0cp00678e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Zn(2+) in the tumor-suppressor protein p53 DNA-binding domain (DBD) is essential for its structural stability and DNA-binding specificity. Mg(2+) has also been recently reported to bind to the p53DBD and influence its DNA-binding activity. In this contribution, the binding geometry of Mg(2+) in the p53DBD and the mechanism of how Mg(2+) affects its DNA-binding activity were investigated using density functional theory (DFT) calculations and molecular dynamics (MD) simulations. Various possible coordination geometries of Mg(2+) binding to histidines (His), cysteines (Cys), and water molecules were studied at the B3LYP/6-311+g** level of theory. The protonation state of Cys and the environment were taken into account to explore the factors governing the coordination geometry. The free energy of the reaction to form the Mg(2+) complexes was estimated, suggesting that the favorable binding mode changes from a four- to six-coordinated geometry as the number of the protonated Cys increases. Furthermore, MD simulations were employed to explore the binding modes of Mg(2+) in the active site of the p53DBD. The simulation results of the Mg(2+) system and the native Zn(2+) system show that the binding affinity of Mg(2+)to the p53DBD is weaker than that of Zn(2+), in agreement with the DFT calculation results and experiments. In addition, the two metal ions are found to make a significant contribution to maintain a favorable orientation for Arg248 to interact with putative DNA, which is critically important to the sequence-specific DNA-binding activity of the p53DBD. However, the effect of Mg(2+) is less marked. Additionally, analysis of the natural bond orbital (NBO) charge transfer reveals that Mg(2+) has a higher net positive charge than Zn(2+), leading to a stronger electrostatic attractive interaction between Mg(2+) and putative DNA. This may partly explain the higher sequence-independent DNA-binding affinity of p53DBD-Mg(2+) compared to p53DBD-Zn(2+) observed in experiment.
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Affiliation(s)
- Teng Wang
- College of Chemistry, Nankai University, Tianjin, 300071, PR China
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Azmi AS, Philip PA, Beck FWJ, Wang Z, Banerjee S, Wang S, Yang D, Sarkar FH, Mohammad RM. MI-219-zinc combination: a new paradigm in MDM2 inhibitor-based therapy. Oncogene 2010; 30:117-26. [PMID: 20818437 PMCID: PMC3000878 DOI: 10.1038/onc.2010.403] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Zinc plays a crucial role in the biology of p53 in that p53 binds to DNA through a structurally complex domain stabilized by zinc atom. The p53 negative regulator MDM2 protein also carries a C-terminal RING domain that coordinates two zinc atoms which are responsible for p53 nuclear export and proteasomal degradation. In this clinically translatable study, we explored the critical role of zinc on p53 re-activation by MDM2-inhibitor MI-219 in colon and breast cancer cells. ZnCl2 enhanced MI-219 activity (MTT, apoptosis and colony formation), and chelation of zinc not only blocked the activity of MI-219, it also suppressed re-activation of the p53 and its downstream effector molecules p21WAF1 and Bax. TPEN, a specific zinc chelator but not Bapta-AM, a calcium chelator, blocked MI-219-induced apoptosis. Nuclear localization is a pre-requisite for proper functioning of p53 and our results confirm that TPEN and not Bapta-AM could abrogate p53 nuclear localization and interfered with p53 transcriptional activation. Addition of zinc suppressed the known p53 feedback MDM2 activation which could be restored by TPEN. Co-immunoprecipitation studies verified that MI-219-mediated MDM2-p53 disruption could be suppressed by TPEN and restored by zinc. As such, single agent therapies that target MDM2 inhibition, without supplemental zinc, may not be optimal in certain patients due to the less recognized mild zinc deficiency among the “at risk population” as in the elderly which are more prone to cancers. Therefore, use of supplemental zinc with MI-219 will benefit the overall efficacy of MDM2 inhibitors and this potent combination warrants further investigation.
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Affiliation(s)
- A S Azmi
- Department of Pathology, Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI 48201, USA
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Abstract
The p53 tumor suppressor is a transcription factor that contains a single zinc ion near its DNA binding interface. Zn(2+) is required for site-specific DNA binding and proper transcriptional activation. In addition to its functional significance, zinc plays a dominant role in determining whether p53 folds productively or misfolds. Insufficient zinc and excess zinc cause p53 to misfold by distinct mechanisms which both result in functional loss. The zinc-binding status of p53 in the cell is impacted significantly by the presence of tumorigenic mutations and by metal ion homeostasis. This review discusses mechanisms by which zinc modulates folding and misfolding of p53, how improper metal binding and release leads to loss of function and cancer, and how misfolding can be rescued by metallochaperones.
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Affiliation(s)
- Stewart N Loh
- Department of Biochemistry & Molecular Biology, State University of New York Upstate Medical University, 750 East Adams Street, Syracuse, NY 13210, USA
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35
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Affiliation(s)
- Wolfgang Maret
- Department of Preventive Medicine & Community Health, The University of Texas Medical Branch, Galveston, Texas 77555-1109, USA.
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36
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Lubin DJ, Butler JS, Loh SN. Folding of tetrameric p53: oligomerization and tumorigenic mutations induce misfolding and loss of function. J Mol Biol 2009; 395:705-16. [PMID: 19913028 DOI: 10.1016/j.jmb.2009.11.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Revised: 10/29/2009] [Accepted: 11/05/2009] [Indexed: 10/20/2022]
Abstract
The physiologically active form of p53 consists of a tetramer of four identical 393-amino-acid subunits associated via their tetramerization domains (TDs; residues 325-355). One in two human tumors contains a point mutation in the DNA binding domain (DBD) of p53 (residues 94-312). Most existing studies on the effects of these mutations on p53 structure and function have been carried out on the isolated DBD fragment, which is monomeric. Recent structural evidence, however, suggests that DBDs may interact with each other in full-length tetrameric forms of p53. Here, we investigate the effects of tumorigenic DBD mutations on the folding of p53 in its tetrameric form. We employ the construct consisting of DBD and TD (amino acids 94-360). We characterize the stability and conformational state of the tumorigenic DBD mutants R248Q, R249S, and R282Q using equilibrium denaturation and functional assays. Destabilizing mutations cause DBD to misfold when it is part of the p53 tetramer, but not when it is monomeric. This conformation is populated under moderately destabilizing conditions (10 degrees C in 2 M urea, and at physiological temperature in the absence of denaturant). Under those same conditions, it is not present in the isolated DBD fragment or in the presence of the TD mutation L344P, which abolishes tetramerization. Misfolding appears to involve intramolecular DBD-DBD association within a single tetrameric molecule. This association is promoted by destabilization of DBD (caused by mutation or elevated temperature) and by the high local DBD concentration enforced by tetramerization of TD. Disrupting the nonnative DBD-DBD interaction or transiently inhibiting tetramerization and allowing p53 to fold as a monomer may be potential strategies for pharmacological intervention in cancer.
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Affiliation(s)
- David J Lubin
- Department of Biochemistry and Molecular Biology, State University of New York Upstate Medical University, 750 East Adams Street, Syracuse, NY 13210, USA
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37
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Cabreiro F, Picot CR, Perichon M, Friguet B, Petropoulos I. Overexpression of methionine sulfoxide reductases A and B2 protects MOLT-4 cells against zinc-induced oxidative stress. Antioxid Redox Signal 2009; 11:215-25. [PMID: 18715149 DOI: 10.1089/ars.2008.2102] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Among the amino acids, methionine is the most susceptible to oxidation, and methionine sulfoxide can be catalytically reduced within proteins by methionine sulfoxide reductase A (MsrA) and B (MsrB). As one of the very few repair systems for oxidized proteins, MsrA and MsrB enzymes play a major role in protein homeostasis during aging and have also been involved in cellular defenses against oxidative stress, by scavenging reactive oxygen species. To elucidate the role of zinc on the Msr system, the effects of zinc treatment on control and stably overexpressing MsrA and MsrB2 MOLT-4 leukemia cells have been analyzed. Here we show that zinc treatment has a pro-antioxidant effect in MOLT-4 cells by inducing the transcription of metallothioneins and positively modulating the activity of the Msr enzymes. In contrast, due to its pro-oxidant effect, zinc also led to increased cell death, reactive oxygen species production, and protein damage. Our results indicate that overexpression of the Msr enzymes, due to their antioxidant properties, counteracts the pro-oxidant effects of zinc treatment, which lead to a cellular protection against protein oxidative damage and cell death, by reducing the production of reactive oxygen species.
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Affiliation(s)
- Filipe Cabreiro
- Laboratoire de Biologie et Biochimie Cellulaire du vieillissement, Université Paris-Diderot-Paris, Paris, France
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38
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Affiliation(s)
- Alessandro Borgia
- Department of Chemistry, Cambridge University, Medical Research Council Centre for Protein Engineering, Cambridge, CB2 1EW, United Kingdom; ,
| | - Philip M. Williams
- Laboratory of Biophysics and Surface Analysis, School of Pharmacy, University of Nottingham, Nottingham NG7 2RD, United Kingdom;
| | - Jane Clarke
- Department of Chemistry, Cambridge University, Medical Research Council Centre for Protein Engineering, Cambridge, CB2 1EW, United Kingdom; ,
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Puca R, Nardinocchi L, Gal H, Rechavi G, Amariglio N, Domany E, Notterman DA, Scarsella M, Leonetti C, Sacchi A, Blandino G, Givol D, D'Orazi G. Reversible Dysfunction of Wild-Type p53 following Homeodomain-Interacting Protein Kinase-2 Knockdown. Cancer Res 2008; 68:3707-14. [DOI: 10.1158/0008-5472.can-07-6776] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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40
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Maret W. Metallothionein redox biology in the cytoprotective and cytotoxic functions of zinc. Exp Gerontol 2008; 43:363-9. [DOI: 10.1016/j.exger.2007.11.005] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2007] [Revised: 11/16/2007] [Accepted: 11/19/2007] [Indexed: 10/22/2022]
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41
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Borgia A, Gianni S, Brunori M, Travaglini-Allocatelli C. Fast folding kinetics and stabilization of apo-cytochrome c. FEBS Lett 2008; 582:1003-7. [PMID: 18307988 DOI: 10.1016/j.febslet.2008.02.046] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2008] [Revised: 02/19/2008] [Accepted: 02/20/2008] [Indexed: 11/25/2022]
Abstract
It is generally accepted that in the c-type cytochromes the covalently bound heme plays a primary role in the acquisition of the folded state. Here, we show that a stabilized site-directed variant of apo-cyt c551 from Pseudomonas aeruginosa (Pa-apocyt F7A/W77F) retains native-like features in the presence of sodium sulfate even in the absence of heme. By time-resolved intrinsic fluorescence, we have evidence that Pa-apocyt F7A/W77F may acquire a compact, native-like conformation within microseconds. These results challenge current thinking about the role of the heme group in the folding of c-type cytochromes.
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Affiliation(s)
- Alessandro Borgia
- Dipartimento di Scienze Biochimiche, A. Rossi Fanelli, Sapienza, Università di Roma, Piazzale A. Moro 5, 00185 Rome, Italy
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Krezel A, Maret W. Dual nanomolar and picomolar Zn(II) binding properties of metallothionein. J Am Chem Soc 2007; 129:10911-21. [PMID: 17696343 DOI: 10.1021/ja071979s] [Citation(s) in RCA: 214] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Each of the seven Zn(II) ions in the Zn(3)S(9) and Zn(4)S(11) clusters of human metallothionein is in a tetrathiolate coordination environment. Yet analysis of Zn(II) association with thionein, the apoprotein, and analysis of Zn(II) dissociation from metallothionein using the fluorescent chelating agents FluoZin-3 and RhodZin-3 reveal at least three classes of sites with affinities that differ by 4 orders of magnitude. Four Zn(II) ions are bound with an apparent average log K of 11.8, and with the methods employed, their binding is indistinguishable. This binding property makes thionein a strong chelating agent. One Zn(II) ion is relatively weakly bound, with a log K of 7.7, making metallothionein a zinc donor in the absence of thionein. The binding data demonstrate that Zn(II) binds with at least four species: Zn(4)T, Zn(5)T, Zn(6)T, and Zn(7)T. Zn(5)T and Zn(6)T bind Zn(II) with a log K of approximately 10 and are the predominant species at micromolar concentrations of metallothionein in cells. Central to the function of the protein is the reactivity of its cysteine side chains in the absence and presence of Zn(II). Chelating agents, such as physiological ligands with moderate affinities for Zn(II), cause dissociation of Zn(II) ions from metallothionein at pH 7.4 (Zn(7)T <==> Zn(7-n)T + nZn(2+)), thereby affecting the reactivity of its thiols. Thus, the rate of thiol oxidation increases in the presence of Zn(II) acceptors but decreases if more free Zn(II) becomes available. Thionein is such an acceptor. It regulates the reactivity and availability of free Zn(II) from metallothionein. At thionein/metallothionein ratios > 0.75, free Zn(II) ions are below a pZn (-log[Zn(2+)](free)) of 11.8, and at ratios < 0.75, relatively large fluctuations of free Zn(II) ions are possible (pZn between 7 and 11). These chemical characteristics match cellular requirements for Zn(II) and suggest how the molecular structures and redox chemistries of metallothionein and thionein determine Zn(II) availability for biological processes.
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Affiliation(s)
- Artur Krezel
- Department of Preventive Medicine and Community Health, The University of Texas Medical Branch, Galveston, Texas 77555, USA
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