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Zhang Y, Liang L, Li Z, Huang Y, Jiang M, Zou B, Xu Y. Polyadenosine diphosphate-ribose polymerase inhibitors: advances, implications, and challenges in tumor radiotherapy sensitization. Front Oncol 2023; 13:1295579. [PMID: 38111536 PMCID: PMC10726039 DOI: 10.3389/fonc.2023.1295579] [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: 09/16/2023] [Accepted: 11/22/2023] [Indexed: 12/20/2023] Open
Abstract
Polyadenosine diphosphate-ribose polymerase (PARP) is a key modifying enzyme in cells, which participates in single-strand break repair and indirectly affects double-strand break repair. PARP inhibitors have shown great potential in oncotherapy by exploiting DNA damage repair pathways, and several small molecule PARP inhibitors have been approved by the U.S. Food and Drug Administration for treating various tumor types. PARP inhibitors not only have significant antitumor effects but also have some synergistic effects when combined with radiotherapy; therefore they have potential as radiation sensitizers. Here, we reviewed the advances and implications of PARP inhibitors in tumor radiotherapy sensitization. First, we summarized the multiple functions of PARP and the mechanisms by which its inhibitors exert antitumor effects. Next, we discuss the immunomodulatory effects of PARP and its inhibitors in tumors. Then, we described the theoretical basis of using PARP inhibitors in combination with radiotherapy and outlined their importance in oncological radiotherapy. Finally, we reviewed the current challenges in this field and elaborated on the future applications of PARP inhibitors as radiation sensitizers. A comprehensive understanding of the mechanism, optimal dosing, long-term safety, and identification of responsive biomarkers remain key challenges to integrating PARP inhibition into the radiotherapy management of cancer patients. Therefore, extensive research in these areas would facilitate the development of precision radiotherapy using PARP inhibitors to improve patient outcomes.
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Affiliation(s)
- Yi Zhang
- Department of Radiation Oncology, Division of Thoracic Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, China
| | - Lijie Liang
- Division of Head & Neck Tumor Multimodality Treatment, Cancer Center, West China Hospital, Sichuan University, Chengdu, China
| | - Zheng Li
- Department of Radiation Oncology, Division of Thoracic Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, China
| | - Ying Huang
- College of Management, Sichuan Agricultural University, Chengdu, China
| | - Ming Jiang
- Division of Head & Neck Tumor Multimodality Treatment, Cancer Center, West China Hospital, Sichuan University, Chengdu, China
| | - Bingwen Zou
- Department of Radiation Oncology, Division of Thoracic Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, China
| | - Yong Xu
- Department of Radiation Oncology, Division of Thoracic Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, China
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2
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Netterfield TS, Ostheimer GJ, Tentner AR, Joughin BA, Dakoyannis AM, Sharma CD, Sorger PK, Janes KA, Lauffenburger DA, Yaffe MB. Biphasic JNK-Erk signaling separates the induction and maintenance of cell senescence after DNA damage induced by topoisomerase II inhibition. Cell Syst 2023; 14:582-604.e10. [PMID: 37473730 PMCID: PMC10627503 DOI: 10.1016/j.cels.2023.06.005] [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: 06/14/2022] [Revised: 03/24/2023] [Accepted: 06/13/2023] [Indexed: 07/22/2023]
Abstract
Genotoxic stress in mammalian cells, including those caused by anti-cancer chemotherapy, can induce temporary cell-cycle arrest, DNA damage-induced senescence (DDIS), or apoptotic cell death. Despite obvious clinical importance, it is unclear how the signals emerging from DNA damage are integrated together with other cellular signaling pathways monitoring the cell's environment and/or internal state to control different cell fates. Using single-cell-based signaling measurements combined with tensor partial least square regression (t-PLSR)/principal component analysis (PCA) analysis, we show that JNK and Erk MAPK signaling regulates the initiation of cell senescence through the transcription factor AP-1 at early times after doxorubicin-induced DNA damage and the senescence-associated secretory phenotype (SASP) at late times after damage. These results identify temporally distinct roles for signaling pathways beyond the classic DNA damage response (DDR) that control the cell senescence decision and modulate the tumor microenvironment and reveal fundamental similarities between signaling pathways responsible for oncogene-induced senescence (OIS) and senescence caused by topoisomerase II inhibition. A record of this paper's transparent peer review process is included in the supplemental information.
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Affiliation(s)
- Tatiana S Netterfield
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Gerard J Ostheimer
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Andrea R Tentner
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Brian A Joughin
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Alexandra M Dakoyannis
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Charvi D Sharma
- David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Computer Science and Molecular Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Peter K Sorger
- Laboratory of Systems Pharmacology, Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Kevin A Janes
- Department of Biomedical Engineering and Department of Biochemistry & Molecular Genetics, University of Virginia, Charlottesville, VA 22908, USA
| | - Douglas A Lauffenburger
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Michael B Yaffe
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Center for Precision Cancer Medicine, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Division of Acute Care Surgery, Trauma, and Surgical Critical Care, and Division of Surgical Oncology, Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
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3
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Farmanbar A, Kneller R, Firouzi S. Mutational signatures reveal mutual exclusivity of homologous recombination and mismatch repair deficiencies in colorectal and stomach tumors. Sci Data 2023; 10:423. [PMID: 37393385 PMCID: PMC10314920 DOI: 10.1038/s41597-023-02331-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 06/26/2023] [Indexed: 07/03/2023] Open
Abstract
Decomposing somatic mutation spectra into mutational signatures and their corresponding etiologies provides a powerful approach for investigating the mechanism of DNA damage and repair. Assessing microsatellite (in)stability (MSI/MSS) status and interpreting their clinical relevance in different malignancies offers significant diagnostic and prognostic value. However, little is known about microsatellite (in)stability and its interactions with other DNA repair mechanisms such as homologous recombination (HR) in different cancer types. Based on whole-genome/exome mutational signature analysis, we showed HR deficiency (HRd) and mismatch repair deficiency (MMRd) occur in a significantly mutually exclusive manner in stomach and colorectal adenocarcinomas. ID11 signature with currently unknown etiology was prevalent in MSS tumors, co-occurred with HRd and was mutually exclusive with MMRd. Apolipoprotein B mRNA editing enzyme, Catalytic polypeptide-like (APOBEC) signature co-occurred with HRd and was mutually exclusive with MMRd in stomach tumors. The HRd signature in MSS tumors and the MMRd signature in MSI tumors were the first or second dominant signatures wherever detected. HRd may drive a distinct subgroup of MSS tumors and lead to poor clinical outcome. These analyses offer insight into mutational signatures in MSI and MMS tumors and reveal opportunities for improved clinical diagnosis and personalized treatment of MSS tumors.
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Affiliation(s)
- Amir Farmanbar
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Tokyo, Japan
- Research Center for Advanced Science and Technology, University of Tokyo, Minato-ku, Tokyo, 153-8904, Japan
| | - Robert Kneller
- Research Center for Advanced Science and Technology, University of Tokyo, Minato-ku, Tokyo, 153-8904, Japan
| | - Sanaz Firouzi
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Tokyo, Japan.
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4
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Therapeutic targeting of the hypoxic tumour microenvironment. Nat Rev Clin Oncol 2021; 18:751-772. [PMID: 34326502 DOI: 10.1038/s41571-021-00539-4] [Citation(s) in RCA: 179] [Impact Index Per Article: 59.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/18/2021] [Indexed: 02/07/2023]
Abstract
Hypoxia is prevalent in human tumours and contributes to microenvironments that shape cancer evolution and adversely affect therapeutic outcomes. Historically, two different tumour microenvironment (TME) research communities have been discernible. One has focused on physicochemical gradients of oxygen, pH and nutrients in the tumour interstitium, motivated in part by the barrier that hypoxia poses to effective radiotherapy. The other has focused on cellular interactions involving tumour and non-tumour cells within the TME. Over the past decade, strong links have been established between these two themes, providing new insights into fundamental aspects of tumour biology and presenting new strategies for addressing the effects of hypoxia and other microenvironmental features that arise from the inefficient microvascular system in solid tumours. This Review provides a perspective on advances at the interface between these two aspects of the TME, with a focus on translational therapeutic opportunities relating to the elimination and/or exploitation of tumour hypoxia.
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5
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Mutations in conserved functional domains of human RecQ helicases are associated with diseases and cancer: A review. Biophys Chem 2020; 265:106433. [DOI: 10.1016/j.bpc.2020.106433] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 07/06/2020] [Accepted: 07/11/2020] [Indexed: 12/12/2022]
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Lee TW, Wong WW, Dickson BD, Lipert B, Cheng GJ, Hunter FW, Hay MP, Wilson WR. Radiosensitization of head and neck squamous cell carcinoma lines by DNA-PK inhibitors is more effective than PARP-1 inhibition and is enhanced by SLFN11 and hypoxia. Int J Radiat Biol 2019; 95:1597-1612. [PMID: 31490091 DOI: 10.1080/09553002.2019.1664787] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Background and purpose: Poly(ADP-ribose)polymerase-1 (PARP1) and DNA-dependent protein kinase (DNA-PK) play key roles in the repair of radiation-induced DNA double strand breaks, but it is unclear which is the preferred therapeutic target in radiotherapy. Here we compare small molecule inhibitors of both as radiosensitizers of head and neck squamous cell carcinoma (HNSCC) cell lines.Methods: Two PARP1 inhibitors (olaparib, veliparib) and two DNA-PK inhibitors (KU57788, IC87361) were tested in 14 HNSCC cell lines and two non-tumorigenic lines (HEK-293 and WI-38/Va-13), with drug exposure for 6 or 24 h post-irradiation, using regrowth assays. For three lines (UT-SCC-54C, -74B, -76B), radiosensitization was also assessed by clonogenic assay under oxia and acute (6 h) anoxia, and for 54C cells under chronic hypoxia (0.2% O2 for 48 h). Relationships between sensitizer enhancement ratios (SER) and gene expression, assessed by RNA sequencing, were evaluated.Results: The inhibitors were minimally cytotoxic in the absence of radiation, with 74B and 54C cells the most sensitive to both olaparib and KU57788. Median SER values for each inhibitor at 1.1 µM were 1.12 (range 1.02-1.24) for olaparib, 1.08 (1.04-1.13) for veliparib, 1.35 (1.10-1.64) for IC87361 and 1.77 (1.41-2.38) for KU57788. The higher SER values for the DNA-PK inhibitors were observed with all cell lines (except HEK-293) and all concentrations tested and were confirmed by clonogenic assay. Radiosensitization by the DNA-PK inhibitors correlated with expression of SLFN11 mRNA. Radiosensitization by IC87361 and olaparib was significantly enhanced under acute anoxia and chronic hypoxia.Conclusions: The DNA-PK inhibitors KU57788 and IC87361 are more effective radiosensitizers than the PARP-1 inhibitors olaparib and veliparib at non-cytotoxic concentrations in HNSCC cell cultures and their activity is enhanced by SLFN11 and hypoxia.
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Affiliation(s)
- Tet Woo Lee
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| | - Way Wua Wong
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Benjamin D Dickson
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Barbara Lipert
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Gary J Cheng
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand
| | - Francis W Hunter
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| | - Michael P Hay
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
| | - William R Wilson
- Auckland Cancer Society Research Centre, University of Auckland, Auckland, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, Auckland, New Zealand
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7
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Wang W, Zhan L, Guo D, Xiang Y, Zhang Y, Tian M, Han Z. Transcriptome analysis of pancreatic cancer cell response to treatment with grape seed proanthocyanidins. Oncol Lett 2018; 17:1741-1749. [PMID: 30675233 PMCID: PMC6341838 DOI: 10.3892/ol.2018.9807] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 10/25/2018] [Indexed: 01/09/2023] Open
Abstract
Grape seed proanthocyanidins (GSPs) have been demonstrated to exhibit potential chemotherapeutic efficacy against various cancer types. To determine the underlying molecular mechanisms involved in GSP-induced apoptosis, the present study prepared pancreatic cancer (PC) cells samples, S3, S12 and S24, which were treated with 20 µg/ml GSPs for 3, 12 and 24 h, respectively. Control cell samples, C3, C12 and C24, were also prepared. Using RNA-sequencing, transcriptome comparisons were performed, which identified 966, 3,543 and 4,944 differentially-expressed genes (DEGs) in S3 vs. C3, S12 vs. C12 and S24 vs. C24, respectively. Gene Ontology analysis of the DEGs, revealed that treatment with GSPs is associated with disruption of the cell cycle (CC) in PC cells. Additionally, disruption of transcription, DNA replication and DNA repair were associated with GSP-treatment in PC cells. Network analysis demonstrated that the common DEGs involved in the CC, transcription, DNA replication and DNA repair were integrated, and served essential roles in the control of CC progression in cancer cells. In summary, GSPs may exhibit a potential chemotherapeutic effect on PC cell proliferation.
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Affiliation(s)
- Weihua Wang
- Department of Food Science, College of Life Sciences, Tarim University, Alar, Xinjiang 843300, P.R. China.,Xinjiang Production and Construction Corps Key Laboratory of Deep Processing of Agricultural Products in South Xinjiang, Alar, Xinjiang 843300, P.R. China
| | - Leilei Zhan
- Center for Genome Analysis, ABLife Inc., Wuhan, Hubei 430075, P.R. China
| | - Dongqi Guo
- Department of Food Science, College of Life Sciences, Tarim University, Alar, Xinjiang 843300, P.R. China.,Xinjiang Production and Construction Corps Key Laboratory of Deep Processing of Agricultural Products in South Xinjiang, Alar, Xinjiang 843300, P.R. China
| | - Yanju Xiang
- Department of Food Science, College of Life Sciences, Tarim University, Alar, Xinjiang 843300, P.R. China.,Xinjiang Production and Construction Corps Key Laboratory of Deep Processing of Agricultural Products in South Xinjiang, Alar, Xinjiang 843300, P.R. China
| | - Yu Zhang
- Center for Genome Analysis, ABLife Inc., Wuhan, Hubei 430075, P.R. China
| | - Muxing Tian
- Department of Food Science, College of Life Sciences, Tarim University, Alar, Xinjiang 843300, P.R. China.,Xinjiang Production and Construction Corps Key Laboratory of Deep Processing of Agricultural Products in South Xinjiang, Alar, Xinjiang 843300, P.R. China
| | - Zhanjiang Han
- Department of Food Science, College of Life Sciences, Tarim University, Alar, Xinjiang 843300, P.R. China.,Xinjiang Production and Construction Corps Key Laboratory of Protection and Utilization of Biological Resources in Tarim Basin, Alar, Xinjiang 843300, P.R. China
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8
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Koo GB, Ji JH, Cho H, Morgan MJ, Kim YS. Nuclear TRADD prevents DNA damage-mediated death by facilitating non-homologous end-joining repair. Sci Rep 2017; 7:3332. [PMID: 28611389 PMCID: PMC5469829 DOI: 10.1038/s41598-017-03211-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 04/26/2017] [Indexed: 11/18/2022] Open
Abstract
TNF receptor-associated death domain (TRADD) is an essential mediator of TNF receptor signaling, and serves as an adaptor to recruit other effectors. TRADD has been shown to cycle between the cytoplasm and nucleus due to its nuclear localization (NLS) and export sequences (NES). However, the underlying function of nuclear TRADD is poorly understood. Here we demonstrate that cytoplasmic TRADD translocates to DNA double-strand break sites (DSBs) during the DNA damage response (DDR). Deficiency of TRADD or its sequestration in cytosol leads to accumulation of γH2AX-positive foci in response to DNA damage, which is reversed by nuclear TRADD expression. TRADD facilitates non-homologous end-joining (NHEJ) by recruiting NHEJ repair factors 53BP1 and Ku70/80 complex, whereas TRADD is dispensable for homologous recombination (HR) repair. Finally, an impaired nuclear localization of TRADD triggers cell death through the persistent activation of JNK and accumulation of reactive oxygen species (ROS). Thus, our findings suggest that translocation of TRADD to DSBs into the nucleus contributes to cell survival in response to DNA damage through an activation of DNA damage repair.
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Affiliation(s)
- Gi-Bang Koo
- Department of Biochemistry, Ajou University School of Medicine, Suwon, Gyeonggi, 16499, Republic of Korea.,Department of Biomedical Sciences, graduate School, Ajou University, Suwon, Gyeonggi, 16499, Republic of Korea
| | - Jae-Hoon Ji
- Genomic Instability Research Center, Ajou University School of Medicine, Suwon, Gyeonggi, 16499, Republic of Korea
| | - Hyeseong Cho
- Department of Biochemistry, Ajou University School of Medicine, Suwon, Gyeonggi, 16499, Republic of Korea.,Department of Biomedical Sciences, graduate School, Ajou University, Suwon, Gyeonggi, 16499, Republic of Korea.,Genomic Instability Research Center, Ajou University School of Medicine, Suwon, Gyeonggi, 16499, Republic of Korea
| | - Michael J Morgan
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, Colorado, 80045, USA
| | - You-Sun Kim
- Department of Biochemistry, Ajou University School of Medicine, Suwon, Gyeonggi, 16499, Republic of Korea. .,Department of Biomedical Sciences, graduate School, Ajou University, Suwon, Gyeonggi, 16499, Republic of Korea.
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9
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Repair of oxidatively induced DNA damage by DNA glycosylases: Mechanisms of action, substrate specificities and excision kinetics. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2017; 771:99-127. [PMID: 28342455 DOI: 10.1016/j.mrrev.2017.02.001] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Indexed: 02/07/2023]
Abstract
Endogenous and exogenous reactive species cause oxidatively induced DNA damage in living organisms by a variety of mechanisms. As a result, a plethora of mutagenic and/or cytotoxic products are formed in cellular DNA. This type of DNA damage is repaired by base excision repair, although nucleotide excision repair also plays a limited role. DNA glycosylases remove modified DNA bases from DNA by hydrolyzing the glycosidic bond leaving behind an apurinic/apyrimidinic (AP) site. Some of them also possess an accompanying AP-lyase activity that cleaves the sugar-phosphate chain of DNA. Since the first discovery of a DNA glycosylase, many studies have elucidated the mechanisms of action, substrate specificities and excision kinetics of these enzymes present in all living organisms. For this purpose, most studies used single- or double-stranded oligodeoxynucleotides with a single DNA lesion embedded at a defined position. High-molecular weight DNA with multiple base lesions has been used in other studies with the advantage of the simultaneous investigation of many DNA base lesions as substrates. Differences between the substrate specificities and excision kinetics of DNA glycosylases have been found when these two different substrates were used. Some DNA glycosylases possess varying substrate specificities for either purine-derived lesions or pyrimidine-derived lesions, whereas others exhibit cross-activity for both types of lesions. Laboratory animals with knockouts of the genes of DNA glycosylases have also been used to provide unequivocal evidence for the substrates, which had previously been found in in vitro studies, to be the actual substrates in vivo as well. On the basis of the knowledge gained from the past studies, efforts are being made to discover small molecule inhibitors of DNA glycosylases that may be used as potential drugs in cancer therapy.
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Tsai RYL. Balancing self-renewal against genome preservation in stem cells: How do they manage to have the cake and eat it too? Cell Mol Life Sci 2016; 73:1803-23. [PMID: 26886024 PMCID: PMC5040593 DOI: 10.1007/s00018-016-2152-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 01/18/2016] [Accepted: 01/28/2016] [Indexed: 01/22/2023]
Abstract
Stem cells are endowed with the awesome power of self-renewal and multi-lineage differentiation that allows them to be major contributors to tissue homeostasis. Owing to their longevity and self-renewal capacity, they are also faced with a higher risk of genomic damage compared to differentiated cells. Damage on the genome, if not prevented or repaired properly, will threaten the survival of stem cells and culminate in organ failure, premature aging, or cancer formation. It is therefore of paramount importance that stem cells remain genomically stable throughout life. Given their unique biological and functional requirement, stem cells are thought to manage genotoxic stress somewhat differently from non-stem cells. The focus of this article is to review the current knowledge on how stem cells escape the barrage of oxidative and replicative DNA damage to stay in self-renewal. A clear statement on this subject should help us better understand tissue regeneration, aging, and cancer.
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Affiliation(s)
- Robert Y L Tsai
- Center for Translational Cancer Research, Institute of Biosciences and Technology, Texas A&M University Health Science Center, 2121 W. Holcombe Blvd, Houston, TX, 77030, USA.
- Department of Molecular and Cellular Medicine, Texas A&M University Health Science Center, College Station, TX, 77843, USA.
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11
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Phase I study of LY2603618, a CHK1 inhibitor, in combination with gemcitabine in Japanese patients with solid tumors. Anticancer Drugs 2015; 26:1043-53. [PMID: 26288133 DOI: 10.1097/cad.0000000000000278] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This phase I trial evaluated LY2603618, a selective inhibitor of the DNA damage checkpoint kinase 1, in combination with gemcitabine. Japanese patients with advanced solid tumors were enrolled. All patients received gemcitabine (1000 mg/m on days 1, 8, and 15 every 28 days) and either 170 mg (cohort 1) or 230 mg (cohort 2) of LY2603618. The primary objective was assessment of safety/tolerability. Pharmacokinetic/pharmacodynamic marker profiles were secondary objectives. Of the 17 patients enrolled, dose-limiting toxicities were observed in one patient in cohort 1 (n=7) and in two patients in cohort 2 (n=10). The most common grade 3 or more drug-related treatment-emergent adverse events were hematological. Three patients discontinued because of adverse events. Dose-dependent decreases in LY2603618 exposure were observed, but the LY2603618 pharmacokinetics at each dose were consistent within and between cycles and did not influence gemcitabine pharmacokinetics. Circulating plasma DNA decreased from baseline in all four patients who achieved a partial response. Administration of 170 or 230 mg of LY2603618 following a standard dose of gemcitabine showed acceptable safety and tolerability in Japanese patients with solid tumors.
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12
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Reddy PT, Jaruga P, Nelson BC, Lowenthal MS, Jemth AS, Loseva O, Coskun E, Helleday T, Dizdaroglu M. Production, Purification, and Characterization of ¹⁵N-Labeled DNA Repair Proteins as Internal Standards for Mass Spectrometric Measurements. Methods Enzymol 2015; 566:305-32. [PMID: 26791985 DOI: 10.1016/bs.mie.2015.06.044] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Oxidatively induced DNA damage is caused in living organisms by a variety of damaging agents, resulting in the formation of a multiplicity of lesions, which are mutagenic and cytotoxic. Unless repaired by DNA repair mechanisms before DNA replication, DNA lesions can lead to genomic instability, which is one of the hallmarks of cancer. Oxidatively induced DNA damage is mainly repaired by base excision repair pathway with the involvement of a plethora of proteins. Cancer tissues develop greater DNA repair capacity than normal tissues by overexpressing DNA repair proteins. Increased DNA repair in tumors that removes DNA lesions generated by therapeutic agents before they became toxic is a major mechanism in the development of therapy resistance. Evidence suggests that DNA repair capacity may be a predictive biomarker of patient response. Thus, knowledge of DNA-protein expressions in disease-free and cancerous tissues may help predict and guide development of treatments and yield the best therapeutic response. Our laboratory has developed methodologies that use mass spectrometry with isotope dilution for the measurement of expression of DNA repair proteins in human tissues and cultured cells. For this purpose, full-length (15)N-labeled analogs of a number of human DNA repair proteins have been produced and purified to be used as internal standards for positive identification and accurate quantification. This chapter describes in detail the protocols of this work. The use of (15)N-labeled proteins as internal standards for the measurement of several DNA repair proteins in vivo is also presented.
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Affiliation(s)
- Prasad T Reddy
- Institute for Bioscience and Biotechnology Research, National Institute of Standards and Technology and the University of Maryland, Rockville, Maryland, USA.
| | - Pawel Jaruga
- Biochemical Measurement Division, National Institute of Standards and Technology, Gaithersburg, Maryland, USA
| | - Bryant C Nelson
- Biosystems and Biomaterials Division, National Institute of Standards and Technology, Gaithersburg, Maryland, USA
| | - Mark S Lowenthal
- Biochemical Measurement Division, National Institute of Standards and Technology, Gaithersburg, Maryland, USA
| | - Ann-Sofie Jemth
- Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Olga Loseva
- Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Erdem Coskun
- Biochemical Measurement Division, National Institute of Standards and Technology, Gaithersburg, Maryland, USA
| | - Thomas Helleday
- Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Miral Dizdaroglu
- Biochemical Measurement Division, National Institute of Standards and Technology, Gaithersburg, Maryland, USA.
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13
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Li B, Sun L, Cai J, Wang C, Wang M, Qiu H, Zuo Z. Modulation of the DNA repair system and ATR-p53 mediated apoptosis is relevant for tributyltin-induced genotoxic effects in human hepatoma G2 cells. J Environ Sci (China) 2015; 27:108-114. [PMID: 25597668 DOI: 10.1016/j.jes.2014.05.032] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 04/14/2014] [Accepted: 05/12/2014] [Indexed: 06/04/2023]
Abstract
The toxic effects of tributyltin (TBT) have been extensively documented in several types of cells, but the molecular mechanisms related to the genotoxic effects of TBT have still not been fully elucidated. Our study showed that exposure of human hepatoma G2 cells to 1-4 μmol/L TBT for 3 hr caused severe DNA damage in a concentration-dependent manner. Moreover, the expression levels of key DNA damage sensor genes such as the replication factor C, proliferating cell nuclear antigen and poly (ADP-ribose) polymerase-1 were inhabited in a concentration-dependent manner. We further demonstrated that TBT induced cell apoptosis via the p53-mediated pathway, which was most likely activated by the ataxia telangiectasia mutated and rad-3 related (ATR) protein kinase. The results also showed that cytochrome c, caspase-3, caspase-8, caspase-9, and the B-cell lymphoma 2 were involved in this process. Taken together, we demonstrated for the first time that the inhibition of the DNA repair system might be more responsible for TBT-induced genotoxic effects in cells. Then the generated DNA damage induced by TBT initiated ATR-p53-mediated apoptosis.
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Affiliation(s)
- Bowen Li
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361102, China.
| | - Lingbin Sun
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361102, China; Department of Gynaecology, The Affiliated Chenggong Hospital of Xiamen University, Xiamen 361002, China
| | - Jiali Cai
- Department of Gynaecology, The Affiliated Chenggong Hospital of Xiamen University, Xiamen 361002, China
| | - Chonggang Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Mengmeng Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Huiling Qiu
- Department of Gynaecology, The Affiliated Chenggong Hospital of Xiamen University, Xiamen 361002, China.
| | - Zhenghong Zuo
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen 361102, China.
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14
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Oxidatively induced DNA damage and its repair in cancer. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2014; 763:212-45. [PMID: 25795122 DOI: 10.1016/j.mrrev.2014.11.002] [Citation(s) in RCA: 179] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 11/03/2014] [Accepted: 11/04/2014] [Indexed: 12/28/2022]
Abstract
Oxidatively induced DNA damage is caused in living organisms by endogenous and exogenous reactive species. DNA lesions resulting from this type of damage are mutagenic and cytotoxic and, if not repaired, can cause genetic instability that may lead to disease processes including carcinogenesis. Living organisms possess DNA repair mechanisms that include a variety of pathways to repair multiple DNA lesions. Mutations and polymorphisms also occur in DNA repair genes adversely affecting DNA repair systems. Cancer tissues overexpress DNA repair proteins and thus develop greater DNA repair capacity than normal tissues. Increased DNA repair in tumors that removes DNA lesions before they become toxic is a major mechanism for development of resistance to therapy, affecting patient survival. Accumulated evidence suggests that DNA repair capacity may be a predictive biomarker for patient response to therapy. Thus, knowledge of DNA protein expressions in normal and cancerous tissues may help predict and guide development of treatments and yield the best therapeutic response. DNA repair proteins constitute targets for inhibitors to overcome the resistance of tumors to therapy. Inhibitors of DNA repair for combination therapy or as single agents for monotherapy may help selectively kill tumors, potentially leading to personalized therapy. Numerous inhibitors have been developed and are being tested in clinical trials. The efficacy of some inhibitors in therapy has been demonstrated in patients. Further development of inhibitors of DNA repair proteins is globally underway to help eradicate cancer.
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15
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Dean RA, Fam HK, An J, Choi K, Shimizu Y, Jones SJM, Boerkoel CF, Interthal H, Pfeifer TA. Identification of a putative Tdp1 inhibitor (CD00509) by in vitro and cell-based assays. ACTA ACUST UNITED AC 2014; 19:1372-82. [PMID: 25117203 DOI: 10.1177/1087057114546551] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Mutations of DNA repair pathways contribute to tumorigenesis and provide a therapeutic target for synthetic lethal interactions in tumor cells. Given that tyrosyl-DNA phosphodiesterase 1 (Tdp1) repairs stalled topoisomerase-I DNA complexes, we hypothesized that inhibition of Tdp1 has synthetic lethal effects in some cancers. To test this, we screened tumor arrays for Tdp1 expression and observed that Tdp1 is expressed in many tumors, including more than 90% of human breast tumors. Subsequent chemical screening identified putative Tdp1 inhibitors. Treatment of control human mammary epithelial cells and the breast cancer cell line MCF-7 with compound CD00509 preferentially sensitized MCF-7 cells to camptothecin and decreased cell proliferation 25% more than camptothecin treatment alone. This suggests that CD00509 specifically targeted Tdp1 in vitro, and CD00509 increased the sensitivity of wild-type murine embryonic fibroblasts (MEFs) to camptothecin to a degree comparable to that of Tdp1(-/-) MEFs. In addition, consistent with poly ADP-ribose polymerase-1 (PARP-1) collaborating with Tdp1 in DNA repair, combined Tdp1 and PARP-1 inhibition was more detrimental to MCF-7 cells than either treatment alone, whereas the combination was not additively harmful to control mammary cells. We conclude that targeting Tdp1 in anticancer therapy preferentially enhances the sensitivity of some breast cancer cells to camptothecin and may be an effective adjuvant for breast cancer therapy.
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Affiliation(s)
- Richard A Dean
- Centre for Drug Research and Development, Vancouver, BC, Canada
| | - Hok Khim Fam
- Child and Family Research Institute, University of British Columbia, Vancouver, BC, Canada Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Jianghong An
- Genome Sciences Centre, BC Cancer Agency, Vancouver, BC, Canada
| | - Kunho Choi
- Child and Family Research Institute, University of British Columbia, Vancouver, BC, Canada Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Yoko Shimizu
- Centre for Drug Research and Development, Vancouver, BC, Canada
| | - Steven J M Jones
- Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada Genome Sciences Centre, BC Cancer Agency, Vancouver, BC, Canada Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada
| | - Cornelius F Boerkoel
- Child and Family Research Institute, University of British Columbia, Vancouver, BC, Canada Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada
| | - Heidrun Interthal
- Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Tom A Pfeifer
- Centre for Drug Research and Development, Vancouver, BC, Canada
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16
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Lin T, Meng L, Lin TC, Wu LJ, Pederson T, Tsai RYL. Nucleostemin and GNL3L exercise distinct functions in genome protection and ribosome synthesis, respectively. J Cell Sci 2014; 127:2302-12. [PMID: 24610951 DOI: 10.1242/jcs.143842] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The mammalian nucleolar proteins nucleostemin and GNL3-like (GNL3L) are encoded by paralogous genes that arose from an ancestral invertebrate gene, GNL3. Invertebrate GNL3 has been implicated in ribosome biosynthesis, as has its mammalian descendent, GNL3L. The paralogous mammalian nucleostemin protein has, instead, been implicated in cell renewal. Here, we found that depletion of nucleostemin in a human breast carcinoma cell line triggers prompt and significant DNA damage in S-phase cells without perturbing the initial step of ribosomal (r)RNA synthesis and only mildly affects the total ribosome production. By contrast, GNL3L depletion markedly impairs ribosome production without inducing appreciable DNA damage. These results indicate that, during vertebrate evolution, GNL3L retained the role of the ancestral gene in ribosome biosynthesis, whereas the paralogous nucleostemin acquired a novel genome-protective function. Our results provide a coherent explanation for what had seemed to be contradictory findings about the functions of the invertebrate versus vertebrate genes and are suggestive of how the nucleolus was fine-tuned for a role in genome protection and cell-cycle control as the vertebrates evolved.
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Affiliation(s)
- Tao Lin
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA
| | - Lingjun Meng
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA
| | - Tsung-Chin Lin
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA
| | - Laura J Wu
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA
| | - Thoru Pederson
- Program in Cell and Developmental Dynamics, Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Robert Y L Tsai
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA
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17
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Lin T, Ibrahim W, Peng CY, Finegold MJ, Tsai RY. A novel role of nucleostemin in maintaining the genome integrity of dividing hepatocytes during mouse liver development and regeneration. Hepatology 2013; 58:2176-87. [PMID: 23813570 PMCID: PMC3844114 DOI: 10.1002/hep.26600] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Accepted: 06/17/2013] [Indexed: 01/04/2023]
Abstract
UNLABELLED During liver development and regeneration, hepatocytes undergo rapid cell division and face an increased risk of DNA damage associated with active DNA replication. The mechanism that protects proliferating hepatocytes from replication-induced DNA damage remains unclear. Nucleostemin (NS) is known to be up-regulated during liver regeneration, and loss of NS is associated with increased DNA damage in cancer cells. To determine whether NS is involved in protecting the genome integrity of proliferating hepatocytes, we created an albumin promoter-driven NS conditional-null (albNS(cko) ) mouse model. Livers of albNS(cko) mice begin to show loss of NS in developing hepatocytes from the first postnatal week and increased DNA damage and hepatocellular injury at 1-2 weeks of age. At 3-4 weeks, albNS(cko) livers develop bile duct hyperplasia and show increased apoptotic cells, necrosis, regenerative nodules, and evidence suggestive of hepatic stem/progenitor cell activation. CCl4 treatment enhances degeneration and DNA damage in NS-deleted hepatocytes and increases biliary hyperplasia and A6(+) cells in albNS(cko) livers. After 70% partial hepatectomy, albNS(cko) livers show increased DNA damage in parallel with a blunted and prolonged regenerative response. The DNA damage in NS-depleted hepatocytes is explained by the impaired recruitment of a core DNA repair enzyme, RAD51, to replication-induced DNA damage foci. CONCLUSION This work reveals a novel genome-protective role of NS in developing and regenerating hepatocytes.
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Affiliation(s)
- Tao Lin
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas 77030 USA
| | - Wessam Ibrahim
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas 77030 USA
| | - Cheng-Yuan Peng
- School of Medicine, China Medical University, Taichung, 40402, Taiwan, Division of Hepatogastroenterology, Department of Internal Medicine, China Medical University Hospital, Taichung, 40402, Taiwan
| | - Milton J Finegold
- Gastrointestinal & Hepatobiliary Pathology, Texas Children's Hospital Houston, Texas 77030 USA, Department of Pathology & Immunology, Baylor College of Medicine, Texas 77030 USA
| | - Robert Y.L. Tsai
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas 77030 USA
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18
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Abstract
Helicases have major roles in genome maintenance by unwinding structured nucleic acids. Their prominence is marked by various cancers and genetic disorders that are linked to helicase defects. Although considerable effort has been made to understand the functions of DNA helicases that are important for genomic stability and cellular homeostasis, the complexity of the DNA damage response leaves us with unanswered questions regarding how helicase-dependent DNA repair pathways are regulated and coordinated with cell cycle checkpoints. Further studies may open the door to targeting helicases in order to improve cancer treatments based on DNA-damaging chemotherapy or radiation.
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Affiliation(s)
- Robert M Brosh
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, NIH Biomedical Research Center, 251 Bayview Boulevard, Baltimore, Maryland 21224, USA.
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19
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Nucleostemin deletion reveals an essential mechanism that maintains the genomic stability of stem and progenitor cells. Proc Natl Acad Sci U S A 2013; 110:11415-20. [PMID: 23798389 DOI: 10.1073/pnas.1301672110] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Stem and progenitor cells maintain a robust DNA replication program during the tissue expansion phase of embryogenesis. The unique mechanism that protects them from the increased risk of replication-induced DNA damage, and hence permits self-renewal, remains unclear. To determine whether the genome integrity of stem/progenitor cells is safeguarded by mechanisms involving molecules beyond the core DNA repair machinery, we created a nucleostemin (a stem and cancer cell-enriched protein) conditional-null allele and showed that neural-specific knockout of nucleostemin predisposes embryos to spontaneous DNA damage that leads to severe brain defects in vivo. In cultured neural stem cells, depletion of nucleostemin triggers replication-dependent DNA damage and perturbs self-renewal, whereas overexpression of nucleostemin shows a protective effect against hydroxyurea-induced DNA damage. Mechanistic studies performed in mouse embryonic fibroblast cells showed that loss of nucleostemin triggers DNA damage and growth arrest independently of the p53 status or rRNA synthesis. Instead, nucleostemin is directly recruited to DNA damage sites and regulates the recruitment of the core repair protein, RAD51, to hydroxyurea-induced foci. This work establishes the primary function of nucleostemin in maintaining the genomic stability of actively dividing stem/progenitor cells by promoting the recruitment of RAD51 to stalled replication-induced DNA damage foci.
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20
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Peng G, Dai H, Zhang W, Hsieh HJ, Pan MR, Park YY, Tsai RYL, Bedrosian I, Lee JS, Ira G, Lin SY. Human nuclease/helicase DNA2 alleviates replication stress by promoting DNA end resection. Cancer Res 2012; 72:2802-13. [PMID: 22491672 DOI: 10.1158/0008-5472.can-11-3152] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
In precancerous and cancerous lesions, excessive growth signals resulting from activation of oncogenes or loss of tumor suppressor genes lead to intensive replication stress, which is recognized by a high level of replication-associated DNA double-strand breaks (DSB). However, the molecular mechanism by which cells alleviate excessive replication stress remains unclear. In this study, we report that the human nuclease/helicase DNA2 facilitates homologous recombination to repair replication-associated DNA DSBs, thereby providing cells with survival advantages under conditions of replication stress. The nuclease activity of DNA2 was required for DSB end resection, which allowed subsequent recruitment of RPA and RAD51 to repair DSBs and restart replication. More importantly, DNA2 expression was significantly increased in human cancers and its expression correlated with patient outcome. Our findings therefore indicate that enhanced activity of DSB resection likely constitutes one mechanism whereby precancerous and cancerous cells might alleviate replication stress.
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Affiliation(s)
- Guang Peng
- Department of Clinical Cancer Prevention, The University of Texas MD Anderson Cancer Center, Houston, Texas 77054, USA.
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21
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Dizdaroglu M. Oxidatively induced DNA damage: mechanisms, repair and disease. Cancer Lett 2012; 327:26-47. [PMID: 22293091 DOI: 10.1016/j.canlet.2012.01.016] [Citation(s) in RCA: 181] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Revised: 12/23/2011] [Accepted: 01/11/2012] [Indexed: 12/12/2022]
Abstract
Endogenous and exogenous sources cause oxidatively induced DNA damage in living organisms by a variety of mechanisms. The resulting DNA lesions are mutagenic and, unless repaired, lead to a variety of mutations and consequently to genetic instability, which is a hallmark of cancer. Oxidatively induced DNA damage is repaired in living cells by different pathways that involve a large number of proteins. Unrepaired and accumulated DNA lesions may lead to disease processes including carcinogenesis. Mutations also occur in DNA repair genes, destabilizing the DNA repair system. A majority of cancer cell lines have somatic mutations in their DNA repair genes. In addition, polymorphisms in these genes constitute a risk factor for cancer. In general, defects in DNA repair are associated with cancer. Numerous DNA repair enzymes exist that possess different, but sometimes overlapping substrate specificities for removal of oxidatively induced DNA lesions. In addition to the role of DNA repair in carcinogenesis, recent evidence suggests that some types of tumors possess increased DNA repair capacity that may lead to therapy resistance. DNA repair pathways are drug targets to develop DNA repair inhibitors to increase the efficacy of cancer therapy. Oxidatively induced DNA lesions and DNA repair proteins may serve as potential biomarkers for early detection, cancer risk assessment, prognosis and for monitoring therapy. Taken together, a large body of accumulated evidence suggests that oxidatively induced DNA damage and its repair are important factors in the development of human cancers. Thus this field deserves more research to contribute to the development of cancer biomarkers, DNA repair inhibitors and treatment approaches to better understand and fight cancer.
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Affiliation(s)
- Miral Dizdaroglu
- Biochemical Science Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
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22
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23
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Inhibition of helicase activity by a small molecule impairs Werner syndrome helicase (WRN) function in the cellular response to DNA damage or replication stress. Proc Natl Acad Sci U S A 2011; 108:1525-30. [PMID: 21220316 DOI: 10.1073/pnas.1006423108] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Modulation of DNA repair proteins by small molecules has attracted great interest. An in vitro helicase activity screen was used to identify molecules that modulate DNA unwinding by Werner syndrome helicase (WRN), mutated in the premature aging disorder Werner syndrome. A small molecule from the National Cancer Institute Diversity Set designated NSC 19630 [1-(propoxymethyl)-maleimide] was identified that inhibited WRN helicase activity but did not affect other DNA helicases [Bloom syndrome (BLM), Fanconi anemia group J (FANCJ), RECQ1, RecQ, UvrD, or DnaB). Exposure of human cells to NSC 19630 dramatically impaired growth and proliferation, induced apoptosis in a WRN-dependent manner, and resulted in elevated γ-H2AX and proliferating cell nuclear antigen (PCNA) foci. NSC 19630 exposure led to delayed S-phase progression, consistent with the accumulation of stalled replication forks, and to DNA damage in a WRN-dependent manner. Exposure to NSC 19630 sensitized cancer cells to the G-quadruplex-binding compound telomestatin or a poly(ADP ribose) polymerase (PARP) inhibitor. Sublethal dosage of NSC 19630 and the chemotherapy drug topotecan acted synergistically to inhibit cell proliferation and induce DNA damage. The use of this WRN helicase inhibitor molecule may provide insight into the importance of WRN-mediated pathway(s) important for DNA repair and the replicational stress response.
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24
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Tell G, Wilson DM. Targeting DNA repair proteins for cancer treatment. Cell Mol Life Sci 2010; 67:3569-72. [PMID: 20706767 PMCID: PMC2956794 DOI: 10.1007/s00018-010-0484-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2010] [Accepted: 07/28/2010] [Indexed: 01/23/2023]
Affiliation(s)
- Gianluca Tell
- Molecular Biology Section, Department of Biomedical Sciences and Technologies, School of Medicine, University of Udine, Piazzale Kolbe 4, 33100, Udine, Italy.
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25
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Human RECQ helicases: roles in DNA metabolism, mutagenesis and cancer biology. Semin Cancer Biol 2010; 20:329-39. [PMID: 20934517 DOI: 10.1016/j.semcancer.2010.10.002] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Accepted: 10/01/2010] [Indexed: 12/13/2022]
Abstract
Helicases use the energy of ATP hydrolysis to separate double-stranded nucleic acids to facilitate essential processes such as replication, recombination, transcription and repair. This article focuses on the human RECQ helicase gene and protein family. Loss of function of three different members has been shown to cause Bloom syndrome (BS), Werner syndrome (WS) and Rothmund-Thomson syndrome (RTS). This article outlines clinical and cellular features of these cancer predisposition syndromes, and discusses their pathogenesis in light of our understanding of RECQ helicase biochemical activities and in vivo functions. I also discuss the emerging role for RECQ helicases as predictors of disease risk and the response to therapy.
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26
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Darzynkiewicz Z, Traganos F, Wlodkowic D. Impaired DNA damage response--an Achilles' heel sensitizing cancer to chemotherapy and radiotherapy. Eur J Pharmacol 2009; 625:143-50. [PMID: 19836377 DOI: 10.1016/j.ejphar.2009.05.032] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2009] [Revised: 05/15/2009] [Accepted: 05/19/2009] [Indexed: 12/21/2022]
Abstract
Despite the progress in targeting particular molecular abnormalities specific to different cancers (targeted therapy), chemo- and radiotherapies are still the most effective of all anticancer modalities. Induction of DNA damage and inhibition of cell proliferation are the objects of most chemotherapeutic agents and radiation. Their effectiveness was initially thought to be due to the high rate of proliferation of cancer cells. However, normal cell proliferation rate in some tissues often exceeds that of curable tumors. Most tumors have impaired DNA damage response (DDR) and the evidence is forthcoming that this confers sensitivity to chemo- or radiotherapy. DDR is a complex set of events which elicits a plethora of molecular interactions engaging signaling pathways designed to: (a) halt cell cycle progression and division to prevent transfer of DNA damage to progeny cells; (b) increase the accessibility of the damaged sites to the DNA repair machinery; (c) engage DNA repair mechanisms and (d) activate the apoptotic pathway when DNA cannot be successfully repaired. A defective DDR makes cancer cells unable to effectively stop cell cycle progression, engage in DNA repair and/or trigger the apoptotic program when treated with DNA damaging drugs. With continued exposure to the drug, such cells accumulate DNA damage which leads to their reproductive death that may have features of cell senescence. Cancers with nonfunctional BRCA1 and BRCA2 are particularly sensitive to combined treatment with DNA damaging drugs and inhibitors of poly(ADP-ribose) polymerase. Antitumor strategies are being designed to treat cancers having particular defects in their DDR, concurrent with protecting normal cells.
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Affiliation(s)
- Zbigniew Darzynkiewicz
- Brander Cancer Research Institute and Department of Pathology, New York Medical College, Valhalla, NY, USA.
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27
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Aggarwal M, Brosh RM. Hitting the bull's eye: novel directed cancer therapy through helicase-targeted synthetic lethality. J Cell Biochem 2009; 106:758-63. [PMID: 19173305 DOI: 10.1002/jcb.22048] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Designing strategies for anti-cancer therapy have posed a significant challenge. One approach has been to inhibit specific DNA repair proteins and their respective pathways to enhance chemotherapy and radiation therapy used to treat cancer patients. Synthetic lethality represents an approach that exploits pre-existing DNA repair deficiencies in certain tumors to develop inhibitors of DNA repair pathways that compensate for the tumor-associated repair deficiency. Since helicases play critical roles in the DNA damage response and DNA repair, particularly in actively dividing and replicating cells, it is proposed that the identification and characterization of synthetic lethal relationships of DNA helicases will be of value in developing improved anti-cancer treatment strategies. In this review, we discuss this hypothesis and current evidence for synthetic lethal interactions of eukaryotic DNA helicases in model systems.
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Affiliation(s)
- Monika Aggarwal
- Laboratory of Molecular Gerontology, National Institute on Aging, NIH, NIH Biomedical Research Center, 251 Bayview Drive, Baltimore, Maryland 21224, USA
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28
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Singleton RS, Guise CP, Ferry DM, Pullen SM, Dorie MJ, Brown JM, Patterson AV, Wilson WR. DNA Cross-Links in Human Tumor Cells Exposed to the Prodrug PR-104A: Relationships to Hypoxia, Bioreductive Metabolism, and Cytotoxicity. Cancer Res 2009; 69:3884-91. [DOI: 10.1158/0008-5472.can-08-4023] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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