1
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Ye M, Fang Y, Chen L, Song Z, Bao Q, Wang F, Huang H, Xu J, Wang Z, Xiao R, Han M, Gao S, Liu H, Jiang B, Qing G. Therapeutic targeting nudix hydrolase 1 creates a MYC-driven metabolic vulnerability. Nat Commun 2024; 15:2377. [PMID: 38493213 PMCID: PMC10944511 DOI: 10.1038/s41467-024-46572-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 02/28/2024] [Indexed: 03/18/2024] Open
Abstract
Tumor cells must rewire nucleotide synthesis to satisfy the demands of unbridled proliferation. Meanwhile, they exhibit augmented reactive oxygen species (ROS) production which paradoxically damages DNA and free deoxy-ribonucleoside triphosphates (dNTPs). How these metabolic processes are integrated to fuel tumorigenesis remains to be investigated. MYC family oncoproteins coordinate nucleotide synthesis and ROS generation to drive the development of numerous cancers. We herein perform a Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-based functional screen targeting metabolic genes and identified nudix hydrolase 1 (NUDT1) as a MYC-driven dependency. Mechanistically, MYC orchestrates the balance of two metabolic pathways that act in parallel, the NADPH oxidase 4 (NOX4)-ROS pathway and the Polo like kinase 1 (PLK1)-NUDT1 nucleotide-sanitizing pathway. We describe LC-1-40 as a potent, on-target degrader that depletes NUDT1 in vivo. Administration of LC-1-40 elicits excessive nucleotide oxidation, cytotoxicity and therapeutic responses in patient-derived xenografts. Thus, pharmacological targeting of NUDT1 represents an actionable MYC-driven metabolic liability.
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Affiliation(s)
- Minhui Ye
- Department of Urology, Medical Research Institute, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, 430071, China
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, 430071, China
| | - Yingzhe Fang
- Department of Urology, Medical Research Institute, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, 430071, China
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, 430071, China
| | - Lu Chen
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, 430071, China
| | - Zemin Song
- TaiKang Center for Life and Medical Sciences, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China
| | - Qing Bao
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, 430071, China
| | - Fei Wang
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Hao Huang
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, 430071, China
| | - Jin Xu
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, 430071, China
| | - Ziwen Wang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060, China
| | - Ruijing Xiao
- TaiKang Center for Life and Medical Sciences, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China
| | - Meng Han
- Protein Chemistry and Proteomics Facility, Tsinghua University Technology Center for Protein Research, Beijing, 10084, China
| | - Song Gao
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, 510060, China
| | - Hudan Liu
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, 430071, China
| | - Baishan Jiang
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, 430071, China.
| | - Guoliang Qing
- Department of Urology, Medical Research Institute, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, 430071, China.
- Frontier Science Center for Immunology and Metabolism, Wuhan University, Wuhan, 430071, China.
- TaiKang Center for Life and Medical Sciences, School of Basic Medical Sciences, Wuhan University, Wuhan, 430071, China.
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2
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Ding Y, Liu Q. Targeting the nucleic acid oxidative damage repair enzyme MTH1: a promising therapeutic option. Front Cell Dev Biol 2024; 12:1334417. [PMID: 38357002 PMCID: PMC10864502 DOI: 10.3389/fcell.2024.1334417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Accepted: 01/17/2024] [Indexed: 02/16/2024] Open
Abstract
The accumulation of reactive oxygen species (ROS) plays a pivotal role in the development of various diseases, including cancer. Elevated ROS levels cause oxidative stress, resulting in detrimental effects on organisms and enabling tumors to develop adaptive responses. Targeting these enhanced oxidative stress protection mechanisms could offer therapeutic benefits with high specificity, as normal cells exhibit lower dependency on these pathways. MTH1 (mutT homolog 1), a homolog of Escherichia coli's MutT, is crucial in this context. It sanitizes the nucleotide pool, preventing incorporation of oxidized nucleotides, thus safeguarding DNA integrity. This study explores MTH1's potential as a therapeutic target, particularly in cancer treatment, providing insights into its structure, function, and role in disease progression.
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Affiliation(s)
| | - Qingquan Liu
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Gannan Medical University, Jiangxi, China
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3
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Lukaszewicz M, Ferenc-Mrozek A, Kokosza J, Stefaniuk A, Stepinski J, Bojarska E, Darzynkiewicz E. Mammalian Nudt15 hydrolytic and binding activity on methylated guanosine mononucleotides. EUROPEAN BIOPHYSICS JOURNAL : EBJ 2023; 52:487-495. [PMID: 37644211 PMCID: PMC10618335 DOI: 10.1007/s00249-023-01678-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 07/06/2023] [Accepted: 08/14/2023] [Indexed: 08/31/2023]
Abstract
The Nudt15 enzyme of the NUDIX protein family is the subject of extensive study due to its action on thiopurine drugs used in the treatment of cancer and inflammatory diseases. In addition to thiopurines, Nudt15 is enzymatically active in vitro on several nucleotide substrates. It has also been suggested that this enzyme may play a role in 5'RNA turnover by hydrolyzing m7GDP, a product of mRNA decapping. However, no detailed studies on this substrate with Nudt15 are available. Here, we analyzed the enzymatic activity of Nudt15 with m7GDP, its triphosphate form m7GTP, and the trimethylated counterparts (m32,2,7GDP and m32,2,7GTP). Kinetic data revealed a moderate activity of Nudt15 toward these methylated mononucleotides compared to the dGTP substrate. However m7GDP and m32,2,7GDP showed a distinct stabilization of Nudt15 upon ligand binding, in the same range as dGTP, and thus these two mononucleotides may be used as leading structures in the design of small molecule binders of Nudt15.
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Affiliation(s)
- Maciej Lukaszewicz
- Department of Biophysics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093, Warsaw, Poland.
| | - Aleksandra Ferenc-Mrozek
- Department of Biophysics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093, Warsaw, Poland
| | - Julia Kokosza
- Department of Biophysics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093, Warsaw, Poland
| | - Anna Stefaniuk
- Department of Biophysics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093, Warsaw, Poland
| | - Janusz Stepinski
- Department of Biophysics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093, Warsaw, Poland
| | - Elzbieta Bojarska
- Department of Biophysics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093, Warsaw, Poland
| | - Edward Darzynkiewicz
- Department of Biophysics, Faculty of Physics, University of Warsaw, Pasteura 5, 02-093, Warsaw, Poland
- Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097, Warsaw, Poland
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4
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Karonudib has potent anti-tumor effects in preclinical models of B-cell lymphoma. Sci Rep 2021; 11:6317. [PMID: 33737576 PMCID: PMC7973795 DOI: 10.1038/s41598-021-85613-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 02/23/2021] [Indexed: 11/08/2022] Open
Abstract
Chemo-immunotherapy has improved survival in B-cell lymphoma patients, but refractory/relapsed diseases still represent a major challenge, urging for development of new therapeutics. Karonudib (TH1579) was developed to inhibit MTH1, an enzyme preventing oxidized dNTP-incorporation in DNA. MTH1 is highly upregulated in tumor biopsies from patients with diffuse large B-cell lymphoma (DLBCL) and Burkitt lymphoma, hence confirming a rationale for targeting MTH1. Here, we tested the efficacy of karonudib in vitro and in preclinical B-cell lymphoma models. Using a range of B-cell lymphoma cell lines, karonudib strongly reduced viability at concentrations well tolerated by activated normal B cells. In B-cell lymphoma cells, karonudib increased incorporation of 8-oxo-dGTP into DNA, and prominently induced prometaphase arrest and apoptosis due to failure in spindle assembly. MTH1 knockout cell lines were less sensitive to karonudib-induced apoptosis, but were displaying cell cycle arrest phenotype similar to the wild type cells, indicating a dual inhibitory role of the drug. Karonudib was highly potent as single agent in two different lymphoma xenograft models, including an ABC DLBCL patient derived xenograft, leading to prolonged survival and fully controlled tumor growth. Together, our preclinical findings provide a rationale for further clinical testing of karonudib in B-cell lymphoma.
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Chao MR, Evans MD, Hu CW, Ji Y, Møller P, Rossner P, Cooke MS. Biomarkers of nucleic acid oxidation - A summary state-of-the-art. Redox Biol 2021; 42:101872. [PMID: 33579665 PMCID: PMC8113048 DOI: 10.1016/j.redox.2021.101872] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 01/12/2021] [Accepted: 01/15/2021] [Indexed: 12/12/2022] Open
Abstract
Oxidatively generated damage to DNA has been implicated in the pathogenesis of a wide variety of diseases. Increasingly, interest is also focusing upon the effects of damage to the other nucleic acids, RNA and the (2′-deoxy-)ribonucleotide pools, and evidence is growing that these too may have an important role in disease. LC-MS/MS has the ability to provide absolute quantification of specific biomarkers, such as 8-oxo-7,8-dihydro-2′-deoxyGuo (8-oxodG), in both nuclear and mitochondrial DNA, and 8-oxoGuo in RNA. However, significant quantities of tissue are needed, limiting its use in human biomonitoring studies. In contrast, the comet assay requires much less material, and as little as 5 μL of blood may be used, offering a minimally invasive means of assessing oxidative stress in vivo, but this is restricted to nuclear DNA damage only. Urine is an ideal matrix in which to non-invasively study nucleic acid-derived biomarkers of oxidative stress, and considerable progress has been made towards robustly validating these measurements, not least through the efforts of the European Standards Committee on Urinary (DNA) Lesion Analysis. For urine, LC-MS/MS is considered the gold standard approach, and although there have been improvements to the ELISA methodology, this is largely limited to 8-oxodG. Emerging DNA adductomics approaches, which either comprehensively assess the totality of adducts in DNA, or map DNA damage across the nuclear and mitochondrial genomes, offer the potential to considerably advance our understanding of the mechanistic role of oxidatively damaged nucleic acids in disease. Oxidatively damaged nucleic acids are implicated in the pathogenesis of disease. LC-MS/MS, comet assay and ELISA are often used to study oxidatively damaged DNA. Urinary oxidatively damaged nucleic acids non-invasively reflect oxidative stress. DNA adductomics will aid understanding the role of ROS damaged DNA in disease.
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Affiliation(s)
- Mu-Rong Chao
- Department of Occupational Safety and Health, Chung Shan Medical University, Taichung, 402, Taiwan; Department of Occupational Medicine, Chung Shan Medical University Hospital, Taichung, 402, Taiwan
| | - Mark D Evans
- Leicester School of Allied Health Sciences, Faculty of Health & Life Sciences, De Montfort University, The Gateway, Leicester, LE1 9BH, United Kingdom
| | - Chiung-Wen Hu
- Department of Public Health, Chung Shan Medical University, Taichung, 402, Taiwan
| | - Yunhee Ji
- Department of Environmental Health Sciences, Florida International University, Miami, FL, 33199, USA
| | - Peter Møller
- Section of Environmental Health, Department of Public Health, University of Copenhagen, Øster Farimagsgade 5A, DK, 1014, Copenhagen K, Denmark
| | - Pavel Rossner
- Department of Nanotoxicology and Molecular Epidemiology, Institute of Experimental Medicine of the CAS, 142 20, Prague, Czech Republic
| | - Marcus S Cooke
- Oxidative Stress Group, Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL, 33620, USA.
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Liang S, Ezerskyte M, Wang J, Pelechano V, Dreij K. Transcriptional mutagenesis dramatically alters genome-wide p53 transactivation landscape. Sci Rep 2020; 10:13513. [PMID: 32782319 PMCID: PMC7419513 DOI: 10.1038/s41598-020-70412-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 07/27/2020] [Indexed: 11/29/2022] Open
Abstract
The transcriptional error rate can be significantly increased by the presence of DNA lesions that instruct mis-insertion during transcription; a process referred to as transcriptional mutagenesis (TM) that can result in altered protein function. Herein, we determined the effect of O6-methylguanine (O6-meG) on transcription and subsequent transactivation activity of p53 in human lung H1299 cells. Levels of TM and effects on transactivation were determined genome wide by RNA-seq. Results showed that 47% of all p53 transcripts contained an uridine misincorporation opposite the lesion at 6 h post transfection, which was decreased to 18% at 24 h. TM at these levels reduced DNA binding activity of p53 to 21% and 80% compared to wild type p53, respectively. Gene expression data were analysed to identify differentially expressed genes due to TM of p53. We show a temporal repression of transactivation of > 100 high confidence p53 target genes including regulators of the cell cycle, DNA damage response and apoptosis. In addition, TM repressed the transcriptional downregulation by p53 of several negative regulators of proliferation and differentiation. Our work demonstrates that TM, even when restricting its effect to an individual transcription factor, has the potential to alter gene expression programs and diversify cellular phenotypes.
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Affiliation(s)
- Shuo Liang
- Unit of Biochemical Toxicology, Institute of Environmental Medicine, Karolinska Institutet, 171 77, Stockholm, Sweden
| | - Monika Ezerskyte
- Unit of Biochemical Toxicology, Institute of Environmental Medicine, Karolinska Institutet, 171 77, Stockholm, Sweden.
| | - Jingwen Wang
- Science for Life Laboratory, Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, 171 77, Stockholm, Sweden
| | - Vicent Pelechano
- Science for Life Laboratory, Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, 171 77, Stockholm, Sweden
| | - Kristian Dreij
- Unit of Biochemical Toxicology, Institute of Environmental Medicine, Karolinska Institutet, 171 77, Stockholm, Sweden.
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7
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Current perspectives on the clinical implications of oxidative RNA damage in aging research: challenges and opportunities. GeroScience 2020; 43:487-505. [PMID: 32529593 PMCID: PMC8110629 DOI: 10.1007/s11357-020-00209-w] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 05/28/2020] [Indexed: 02/05/2023] Open
Abstract
Ribonucleic acid (RNA) molecules can be easily attacked by reactive oxygen species (ROS), which are produced during normal cellular metabolism and under various oxidative stress conditions. Numerous findings report that the amount of cellular 8-oxoG, the most abundant RNA damage biomarker, is a promising target for the sensitive measurement of oxidative stress and aging-associated diseases, including neuropsychiatric disorders. Most importantly, available data suggest that RNA oxidation has important implications for various signaling pathways and gene expression regulation in aging-related diseases, highlighting the necessity of using combinations of RNA oxidation adducts in both experimental studies and clinical trials. In this review, we primarily describe evidence for the effect of oxidative stress on RNA integrity modulation and possible quality control systems. Additionally, we discuss the profiles and clinical implications of RNA oxidation products that have been under intensive investigation in several aging-associated medical disorders.
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Scaletti ER, Vallin KS, Bräutigam L, Sarno A, Warpman Berglund U, Helleday T, Stenmark P, Jemth AS. MutT homologue 1 (MTH1) removes N6-methyl-dATP from the dNTP pool. J Biol Chem 2020; 295:4761-4772. [PMID: 32144205 PMCID: PMC7152754 DOI: 10.1074/jbc.ra120.012636] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 03/02/2020] [Indexed: 12/17/2022] Open
Abstract
MutT homologue 1 (MTH1) removes oxidized nucleotides from the nucleotide pool and thereby prevents their incorporation into the genome and thereby reduces genotoxicity. We previously reported that MTH1 is an efficient catalyst of O6-methyl-dGTP hydrolysis suggesting that MTH1 may also sanitize the nucleotide pool from other methylated nucleotides. We here show that MTH1 efficiently catalyzes the hydrolysis of N6-methyl-dATP to N6-methyl-dAMP and further report that N6-methylation of dATP drastically increases the MTH1 activity. We also observed MTH1 activity with N6-methyl-ATP, albeit at a lower level. We show that N6-methyl-dATP is incorporated into DNA in vivo, as indicated by increased N6-methyl-dA DNA levels in embryos developed from MTH1 knock-out zebrafish eggs microinjected with N6-methyl-dATP compared with noninjected embryos. N6-methyl-dATP activity is present in MTH1 homologues from distantly related vertebrates, suggesting evolutionary conservation and indicating that this activity is important. Of note, N6-methyl-dATP activity is unique to MTH1 among related NUDIX hydrolases. Moreover, we present the structure of N6-methyl-dAMP-bound human MTH1, revealing that the N6-methyl group is accommodated within a hydrophobic active-site subpocket explaining why N6-methyl-dATP is a good MTH1 substrate. N6-methylation of DNA and RNA has been reported to have epigenetic roles and to affect mRNA metabolism. We propose that MTH1 acts in concert with adenosine deaminase-like protein isoform 1 (ADAL1) to prevent incorporation of N6-methyl-(d)ATP into DNA and RNA. This would hinder potential dysregulation of epigenetic control and RNA metabolism via conversion of N6-methyl-(d)ATP to N6-methyl-(d)AMP, followed by ADAL1-catalyzed deamination producing (d)IMP that can enter the nucleotide salvage pathway.
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Affiliation(s)
- Emma Rose Scaletti
- Department of Biochemistry and Biophysics, Stockholm University S-106 91, Stockholm, Sweden
- Department of Experimental Medical Science, Lund University, Lund 221 00, Sweden
| | - Karl S Vallin
- Science for Life Laboratory, Department of Oncology-Pathology, Karolinska Institutet, S-171 76 Stockholm, Sweden
| | - Lars Bräutigam
- Science for Life Laboratory, Department of Oncology-Pathology, Karolinska Institutet, S-171 76 Stockholm, Sweden
| | - Antonio Sarno
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, 7491 Trondheim, Norway
- Department of Pathology, St. Olavs Hospital, 7006 Trondheim, Norway
| | - Ulrika Warpman Berglund
- Science for Life Laboratory, Department of Oncology-Pathology, Karolinska Institutet, S-171 76 Stockholm, Sweden
| | - Thomas Helleday
- Science for Life Laboratory, Department of Oncology-Pathology, Karolinska Institutet, S-171 76 Stockholm, Sweden
- Weston Park Cancer Centre, Department of Oncology and Metabolism, University of Sheffield, Sheffield S10 2RX, United Kingdom
| | - Pål Stenmark
- Department of Biochemistry and Biophysics, Stockholm University S-106 91, Stockholm, Sweden
- Department of Experimental Medical Science, Lund University, Lund 221 00, Sweden
| | - Ann-Sofie Jemth
- Science for Life Laboratory, Department of Oncology-Pathology, Karolinska Institutet, S-171 76 Stockholm, Sweden
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Abstract
7,8-Dihydro-8-oxoguanine (oxoG) is the most abundant oxidative DNA lesion with dual coding properties. It forms both Watson–Crick (anti)oxoG:(anti)C and Hoogsteen (syn)oxoG:(anti)A base pairs without a significant distortion of a B-DNA helix. DNA polymerases bypass oxoG but the accuracy of nucleotide incorporation opposite the lesion varies depending on the polymerase-specific interactions with the templating oxoG and incoming nucleotides. High-fidelity replicative DNA polymerases read oxoG as a cognate base for A while treating oxoG:C as a mismatch. The mutagenic effects of oxoG in the cell are alleviated by specific systems for DNA repair and nucleotide pool sanitization, preventing mutagenesis from both direct DNA oxidation and oxodGMP incorporation. DNA translesion synthesis could provide an additional protective mechanism against oxoG mutagenesis in cells. Several human DNA polymerases of the X- and Y-families efficiently and accurately incorporate nucleotides opposite oxoG. In this review, we address the mutagenic potential of oxoG in cells and discuss the structural basis for oxoG bypass by different DNA polymerases and the mechanisms of the recognition of oxoG by DNA glycosylases and dNTP hydrolases.
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Rai P, Sobol RW. Mechanisms of MTH1 inhibition-induced DNA strand breaks: The slippery slope from the oxidized nucleotide pool to genotoxic damage. DNA Repair (Amst) 2019; 77:18-26. [PMID: 30852368 DOI: 10.1016/j.dnarep.2019.03.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 02/28/2019] [Accepted: 03/01/2019] [Indexed: 12/14/2022]
Abstract
Unlike normal tissues, tumor cells possess a propensity for genomic instability, resulting from elevated oxidant levels produced by oncogenic signaling and aberrant cellular metabolism. Thus, targeting mechanisms that protect cancer cells from the tumor-inhibitory consequences of their redox imbalance and spontaneous DNA-damaging events is expected to have broad-spectrum efficacy and a high therapeutic index. One critical mechanism for tumor cell protection from oxidant stress is the hydrolysis of oxidized nucleotides. Human MutT homolog 1 (MTH1), the mammalian nudix (nucleoside diphosphate X) pyrophosphatase (NUDT1), protects tumor cells from oxidative stress-induced genomic DNA damage by cleansing the nucleotide pool of oxidized purine nucleotides. Depletion or pharmacologic inhibition of MTH1 results in genomic DNA strand breaks in many cancer cells. However, the mechanisms underlying how oxidized nucleotides, thought mainly to be mutagenic rather than genotoxic, induce DNA strand breaks are largely unknown. Given the recent therapeutic interest in targeting MTH1, a better understanding of such mechanisms is crucial to its successful translation into the clinic and in identifying the molecular contexts under which its inhibition is likely to be beneficial. Here we provide a comprehensive perspective on MTH1 function and its importance in protecting genome integrity, in the context of tumor-associated oxidative stress and the mechanisms that likely lead to irreparable DNA strand breaks as a result of MTH1 inhibition.
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Affiliation(s)
- Priyamvada Rai
- Department of Medicine/Division of Medical Oncology, University of Miami Miller School of Medicine, Miami, FL, 33136, United States; Sylvester Comprehensive Cancer Center, Miami, FL, 33136, United States.
| | - Robert W Sobol
- Mitchell Cancer Institute, University of South Alabama, 1660 Springhill Avenue, Mobile, AL, 36604, United States.
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