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Duda J, Thomas SN. Interactions of Histone Deacetylase 6 with DNA Damage Repair Factors Strengthen its Utility as a Combination Drug Target in High-Grade Serous Ovarian Cancer. ACS Pharmacol Transl Sci 2023; 6:1924-1933. [PMID: 38107255 PMCID: PMC10723650 DOI: 10.1021/acsptsci.3c00215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 10/23/2023] [Accepted: 10/25/2023] [Indexed: 12/19/2023]
Abstract
High-grade serous ovarian cancer (HGSOC) is the deadliest gynecologic malignancy in women. The low survival rate is largely due to drug resistance. Approximately 80% of patients who initially respond to treatment relapse and become drug-resistant. The lack of effective second-line therapeutics remains a substantial challenge for BRCA-1/2 wild-type HGSOC patients. Histone Deacetylases (HDACs) are promising targets in HGSOC treatment; however, the mechanism and efficacy of HDAC inhibitors are understudied in HGSOC. In order to consider HDACs as a treatment target, an improved understanding of their function within HGSOC is required. This includes elucidating HDAC6-specific protein-protein interactions. In this study, we carried out substrate trapping followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) to elucidate HDAC6 catalytic domain (CD)-specific interactors in the context of BRCA-1/2 wild-type HGSOC. Overall, this study identified new HDAC6 substrates that may be unique to HGSOC. The HDAC6-CD1 mutant condition contained the largest number of significant proteins compared to the CD2 mutant and the CD1/2 mutant conditions, suggesting the HDAC6-CD1 domain has catalytic activity that is independent of CD2. Among the identified substrates were proteins involved in DNA damage repair including PARP proteins. These findings further justify the use of HDAC inhibitors as a combination treatment with platinum chemotherapy agents and PARP inhibitors in HGSOC.
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Affiliation(s)
- Jolene
M. Duda
- Department
of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Stefani N. Thomas
- Department
of Laboratory Medicine and Pathology, University
of Minnesota, Minneapolis, Minnesota 55455, United States
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Hung MH, Chang CW, Wang KC, Chaisaingmongkol J, Ruchirawat M, Greten TF, Wang XW. Purine anabolism creates therapeutic vulnerability in hepatocellular carcinoma through m 6 A-mediated epitranscriptomic regulation. Hepatology 2023; 78:1462-1477. [PMID: 37094826 PMCID: PMC10593095 DOI: 10.1097/hep.0000000000000420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 04/10/2023] [Indexed: 04/26/2023]
Abstract
BACKGROUND AND AIMS Purines are building blocks for the cellular genome, and excessive purine nucleotides are seen in tumors. However, how purine metabolism is dysregulated in tumors, and impacting tumorigenesis remains elusive. APPROACH AND RESULTS Transcriptomic and metabolomic analyses of purine biosynthesis and purine degradation pathways were performed in the tumor and associated nontumor liver tissues obtained from 62 patients with HCC, one of the most lethal cancers worldwide. We found that most genes in purine synthesis are upregulated, while genes in purine degradation are inhibited in HCC tumors. High purine anabolism is associated with unique somatic mutational signatures linked to patient prognosis. Mechanistically, we discover that increasing purine anabolism promotes epitranscriptomic dysregulation of DNA damage repairing (DDR) machinery through upregulating RNA N6-methyladenosine (m 6 A) modification. High purine anabolic HCC is sensitive to DDR-targeting agents but not to standard HCC treatments, correlating with the clinical outcomes in 5 independent HCC cohorts containing 724 patients. We further showed that high purine anabolism determines the sensitivity to DDR-targeting agents in 5 HCC cell lines in vitro and in vivo . CONCLUSIONS Our results reveal a central role of purine anabolism in regulating DDR, which could be therapeutically exploited in HCC.
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Affiliation(s)
- Man Hsin Hung
- Laboratory of Human Carcinogenesis, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Ching Wen Chang
- Laboratory of Human Carcinogenesis, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Kathy Cheng Wang
- Laboratory of Human Carcinogenesis, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Jittiporn Chaisaingmongkol
- Laboratory of Chemical Carcinogenesis, Chulabhorn Research Institute, Bangkok 10210, Thailand
- Center of Excellence on Environmental Health and Toxicology (EHT), OPS, MHESI, Thailand
| | - Mathuros Ruchirawat
- Laboratory of Chemical Carcinogenesis, Chulabhorn Research Institute, Bangkok 10210, Thailand
- Center of Excellence on Environmental Health and Toxicology (EHT), OPS, MHESI, Thailand
| | - Tim F. Greten
- Thoracic and Gastrointestinal Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
- Liver Cancer Program, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Xin Wei Wang
- Laboratory of Human Carcinogenesis, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
- Liver Cancer Program, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
- Lead contact
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Park JC, Kim YJ, Han JH, Kim D, Park MJ, Kim J, Jang HK, Bae S, Cha HJ. MutSα and MutSβ as size-dependent cellular determinants for prime editing in human embryonic stem cells. Mol Ther Nucleic Acids 2023; 32:914-922. [PMCID: PMC10280094 DOI: 10.1016/j.omtn.2023.05.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 05/10/2023] [Indexed: 06/22/2023]
Abstract
Precise genome editing in human pluripotent stem cells (hPSCs) has potential applications in isogenic disease modeling and ex vivo stem cell therapy, necessitating diverse genome editing tools. However, unlike differentiated somatic cells, hPSCs have unique cellular properties that maintain genome integrity, which largely determine the overall efficiency of an editing tool. Considering the high demand for prime editors (PEs), it is imperative to characterize the key molecular determinants of PE outcomes in hPSCs. Through homozygous knockout (KO) of MMR pathway key proteins MSH2, MSH3, and MSH6, we reveal that MutSα and MutSβ determine PE efficiency in an editing size-dependent manner. Notably, MSH2 perturbation disrupted both MutSα and MutSβ complexes, dramatically escalating PE efficiency from base mispair to 10 bases, up to 50 folds. Similarly, impaired MutSα by MSH6 KO improved editing efficiency from single to three base pairs, while defective MutSβ by MSH3 KO heightened efficiency from three to 10 base pairs. Thus, the size-dependent effect of MutSα and MutSβ on prime editing implies that MMR is a vital PE efficiency determinant in hPSCs and highlights the distinct roles of MutSα and MutSβ in its outcome.
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Affiliation(s)
- Ju-Chan Park
- College of Pharmacy, Seoul National University, Seoul, Republic of Korea
| | - Yun-Jeong Kim
- College of Pharmacy, Seoul National University, Seoul, Republic of Korea
| | - Jun Hee Han
- Department of Chemistry, Hanyang University, Seoul, Republic of Korea
| | - Dayeon Kim
- College of Pharmacy, Seoul National University, Seoul, Republic of Korea
| | - Mihn Jeong Park
- College of Pharmacy, Seoul National University, Seoul, Republic of Korea
| | - Jumee Kim
- College of Pharmacy, Seoul National University, Seoul, Republic of Korea
| | - Hyeon-Ki Jang
- Division of Chemical Engineering and Bioengineering, College of Art Culture and Engineering, Kangwon National University, Chuncheon, South Korea
| | - Sangsu Bae
- College of Medicine, Seoul National University, Seoul, Republic of Korea
| | - Hyuk-Jin Cha
- College of Pharmacy, Seoul National University, Seoul, Republic of Korea
- Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Republic of Korea
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Schweizer MT, Gulati R, Yezefski T, Cheng HH, Mostaghel E, Haffner MC, Patel RA, De Sarkar N, Ha G, Dumpit R, Woo B, Lin A, Panlasigui P, McDonald N, Lai M, Nega K, Hammond J, Grivas P, Hsieh A, Montgomery B, Nelson PS, Yu EY. Bipolar androgen therapy plus olaparib in men with metastatic castration-resistant prostate cancer. Prostate Cancer Prostatic Dis 2023; 26:194-200. [PMID: 36564459 PMCID: PMC10286318 DOI: 10.1038/s41391-022-00636-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 12/07/2022] [Accepted: 12/13/2022] [Indexed: 12/24/2022]
Abstract
BACKGROUND Bipolar androgen therapy (BAT) results in rapid fluctuation of testosterone (T) between near-castrate and supraphysiological levels and has shown promise in metastatic castration-resistant prostate cancer (mCRPC). Its clinical effects may be mediated through induction of DNA damage, and preclinical studies suggest synergy with PARP inhibitors. PATIENTS AND METHODS This was a single-center, Phase II trial testing olaparib plus BAT (T cypionate/enanthate 400 mg every 28 days) with ongoing androgen deprivation. Planned recruitment was 30 subjects (equal proportions with/without homologous recombination repair [HRR] gene mutations) with mCRPC post abiraterone and/or enzalutamide. The primary objective was to determine PSA50 response (PSA decline ≥50% from baseline) rate at 12-weeks. The primary analysis utilized the entire (intent-to-treat [ITT]) cohort, with those dropping out early counted as non-responders. Secondary/exploratory analyses were in those treated beyond 12-weeks (response-evaluable cohort). RESULTS Thirty-six patients enrolled and 6 discontinued prior to response assessment. In the ITT cohort, PSA50 response rate at 12-weeks was 11/36 (31%; 95% CI 17-48%), and 16/36 (44%, 95% CI 28-62%) had a PSA50 response at any time on-study. After a median follow-up of 19 months, the median clinical/radiographic progression-free survival in the ITT cohort was 13.0 months (95% CI 7-17). Clinical outcomes were similar regardless of HRR gene mutational status. CONCLUSIONS BAT plus olaparib is associated with high response rates and long PFS. Clinical benefit was observed regardless of HRR gene mutational status.
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Affiliation(s)
- Michael T Schweizer
- Department of Medicine, University of Washington, Seattle, WA, USA.
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, USA.
| | - Roman Gulati
- Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Todd Yezefski
- Department of Medicine, University of Washington, Seattle, WA, USA
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Heather H Cheng
- Department of Medicine, University of Washington, Seattle, WA, USA
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Elahe Mostaghel
- Department of Medicine, University of Washington, Seattle, WA, USA
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
- VA Puget Sound Health Care System, Seattle, WA, USA
| | - Michael C Haffner
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA
| | - Radhika A Patel
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Navonil De Sarkar
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Gavin Ha
- Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Ruth Dumpit
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Brianna Woo
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Aaron Lin
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Patrick Panlasigui
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Nerina McDonald
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Michael Lai
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Katie Nega
- Department of Medicine, University of Washington, Seattle, WA, USA
| | - Jeannette Hammond
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Petros Grivas
- Department of Medicine, University of Washington, Seattle, WA, USA
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Andrew Hsieh
- Department of Medicine, University of Washington, Seattle, WA, USA
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Bruce Montgomery
- Department of Medicine, University of Washington, Seattle, WA, USA
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
- VA Puget Sound Health Care System, Seattle, WA, USA
| | - Peter S Nelson
- Department of Medicine, University of Washington, Seattle, WA, USA
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Evan Y Yu
- Department of Medicine, University of Washington, Seattle, WA, USA
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA, USA
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Shakyawar SK, Mishra NK, Vellichirammal NN, Cary L, Helikar T, Powers R, Oberley-Deegan RE, Berkowitz DB, Bayles KW, Singh VK, Guda C. A Review of Radiation-Induced Alterations of Multi-Omic Profiles, Radiation Injury Biomarkers, and Countermeasures. Radiat Res 2023; 199:89-111. [PMID: 36368026 PMCID: PMC10279411 DOI: 10.1667/rade-21-00187.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 10/24/2022] [Indexed: 11/13/2022]
Abstract
Increasing utilization of nuclear power enhances the risks associated with industrial accidents, occupational hazards, and the threat of nuclear terrorism. Exposure to ionizing radiation interferes with genomic stability and gene expression resulting in the disruption of normal metabolic processes in cells and organs by inducing complex biological responses. Exposure to high-dose radiation causes acute radiation syndrome, which leads to hematopoietic, gastrointestinal, cerebrovascular, and many other organ-specific injuries. Altered genomic variations, gene expression, metabolite concentrations, and microbiota profiles in blood plasma or tissue samples reflect the whole-body radiation injuries. Hence, multi-omic profiles obtained from high-resolution omics platforms offer a holistic approach for identifying reliable biomarkers to predict the radiation injury of organs and tissues resulting from radiation exposures. In this review, we performed a literature search to systematically catalog the radiation-induced alterations from multi-omic studies and radiation countermeasures. We covered radiation-induced changes in the genomic, transcriptomic, proteomic, metabolomic, lipidomic, and microbiome profiles. Furthermore, we have covered promising multi-omic biomarkers, FDA-approved countermeasure drugs, and other radiation countermeasures that include radioprotectors and radiomitigators. This review presents an overview of radiation-induced alterations of multi-omics profiles and biomarkers, and associated radiation countermeasures.
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Affiliation(s)
- Sushil K Shakyawar
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Nitish K Mishra
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Neetha N Vellichirammal
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Lynnette Cary
- Division of Radioprotectants, Department of Pharmacology and Molecular Therapeutics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
- Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Tomáš Helikar
- Department of Biochemistry, University of Nebraska-Lincoln, Lincoln NE 65888, USA
| | - Robert Powers
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln NE 65888, USA
- Nebraska Center for Integrated Biomolecular Communication, University of Nebraska-Lincoln, Lincoln NE 68588, USA
| | - Rebecca E Oberley-Deegan
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - David B Berkowitz
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln NE 65888, USA
| | - Kenneth W Bayles
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Vijay K Singh
- Division of Radioprotectants, Department of Pharmacology and Molecular Therapeutics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
- Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Chittibabu Guda
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Center for Biomedical Informatics Research and Innovation, University of Nebraska Medical Center, Omaha, NE 68198, USA
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6
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Reiss KA, Mick R, Teitelbaum U, O'Hara M, Schneider C, Massa R, Karasic T, Tondon R, Onyiah C, Gosselin MK, Donze A, Domchek SM, Vonderheide RH. Niraparib plus nivolumab or niraparib plus ipilimumab in patients with platinum-sensitive advanced pancreatic cancer: a randomised, phase 1b/2 trial. Lancet Oncol 2022; 23:1009-1020. [PMID: 35810751 PMCID: PMC9339497 DOI: 10.1016/s1470-2045(22)00369-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 05/26/2022] [Accepted: 05/30/2022] [Indexed: 12/13/2022]
Abstract
BACKGROUND Establishing alternatives to lifelong chemotherapy for patients with advanced pancreatic cancer has been proposed to address chemotherapy resistance and cumulative toxicity. Poly(ADP-ribose) polymerase (PARP) inhibitors have shown efficacy in this setting, and concurrent immune checkpoint blockade could offer synergistic tumour control. The aim of this study was to test the safety and antitumour activity of maintenance with PARP inhibition combined with immune checkpoint blockade in patients with advanced pancreatic cancer who had a stable response to platinum-based chemotherapy. METHODS We conducted an open-label, randomised, phase 1b/2 study of niraparib plus anti-PD-1 (nivolumab) or anti-CTLA-4 (ipilimumab) therapy for patients with advanced pancreatic cancer whose cancer had not progressed after at least 16 weeks of platinum-based therapy. Patients were randomly assigned (1:1) via permuted block randomisation (block sizes 2 and 4) to niraparib 200 mg orally per day plus either nivolumab 240 mg intravenously every 2 weeks (later changed to 480 mg intravenously every 4 weeks based on manufacturer update) or ipilimumab 3 mg/kg intravenously every 4 weeks for four doses. The primary endpoints were safety and progression-free survival at 6 months. Treatment groups were not compared for activity, which was assessed in each group against a clinically meaningful progression-free survival at 6 months of 44% (null hypothesis). Superiority of a treatment regimen could be declared if 6-month progression-free survival was 60%, and inferiority if 6-month progression-free survival was 27%. All patients who received at least one dose of study treatment and had at least one post-treatment assessment of response according to Response Evaluation Criteria in Solid Tumours version 1.1 were included in the efficacy population. The safety population consisted of all patients who received at least one dose of study treatment. This study is registered with ClinicalTrials.gov, NCT03404960, and enrolment is completed and follow-up is ongoing. FINDINGS 91 patients were enrolled between Feb 7, 2018, and Oct 5, 2021 and were randomly assigned to niraparib plus nivolumab (n=46) or niraparib plus ipilimumab (n=45). Of these patients, 84 were evaluable for the progression-free survival endpoint (niraparib plus nivolumab=44; niraparib plus ipilimumab=40). Median follow-up was 23·0 months (IQR 15·0-31·5). 6-month progression-free survival was 20·6% (95% CI 8·3-32·9; p=0·0002 vs the null hypothesis of 44%) in the niraparib plus nivolumab group; and 59·6% (44·3-74·9; p=0·045) in the niraparib plus ipilimumab group. Ten (22%) of 46 patients in the niraparib plus nivolumab group and 23 (50%) of 45 patients in the niraparib plus ipilimumab group had a grade 3 or worse treatment-related adverse event. The most common grade 3 or worse adverse events in the niraparib plus nivolumab group were hypertension (in four [8%] patients), anaemia (two [4%]), and thrombocytopenia (two [4%]) whereas in the niraparib plus ipilimumab group these were fatigue (in six [14%]), anaemia (five [11%]), and hypertension (four [9%]). There were no treatment-related deaths. INTERPRETATION The primary endpoint of 6-month progression-free survival was met in the niraparib plus ipilimumab maintenance group, whereas niraparib plus nivolumab yielded inferior progression-free survival. These findings highlight the potential for non-cytotoxic maintenance therapies in patients with advanced pancreatic cancer. FUNDING Bristol Myers Squibb, GlaxoSmithKline, the Basser Center Young Leadership Council, The Konner Foundation, The Pearl and Philip Basser Innovation Research Award, the Anonymous Foundation, and the US National Institutes of Health.
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Affiliation(s)
- Kim A Reiss
- Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, PA, USA; Department of Medicine, University of Pennsylvania, PA, USA.
| | - Rosemarie Mick
- Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, PA, USA; Department of Biostatistics, Epidemiology and Informatics, University of Pennsylvania, PA, USA
| | - Ursina Teitelbaum
- Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, PA, USA; Department of Medicine, University of Pennsylvania, PA, USA
| | - Mark O'Hara
- Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, PA, USA; Department of Medicine, University of Pennsylvania, PA, USA
| | - Charles Schneider
- Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, PA, USA; Department of Medicine, University of Pennsylvania, PA, USA
| | - Ryan Massa
- Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, PA, USA; Department of Medicine, University of Pennsylvania, PA, USA
| | - Thomas Karasic
- Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, PA, USA; Department of Medicine, University of Pennsylvania, PA, USA
| | - Rashmi Tondon
- Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, PA, USA; Department of Pathology, University of Pennsylvania, PA, USA
| | - Chioma Onyiah
- Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, PA, USA; Department of Medicine, University of Pennsylvania, PA, USA
| | - Mary Kate Gosselin
- Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, PA, USA; Department of Medicine, University of Pennsylvania, PA, USA
| | - Alyssa Donze
- Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, PA, USA; Department of Medicine, University of Pennsylvania, PA, USA
| | - Susan M Domchek
- Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, PA, USA; Department of Medicine, University of Pennsylvania, PA, USA
| | - Robert H Vonderheide
- Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, PA, USA; Department of Medicine, University of Pennsylvania, PA, USA
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Kornepati AV, Boyd JT, Murray CE, Saifetiarova J, de la Peña Avalos B, Rogers CM, Bai H, Padron AS, Liao Y, Ontiveros C, Svatek RS, Hromas R, Li R, Hu Y, Conejo-Garcia JR, Vadlamudi RK, Zhao W, Dray E, Sung P, Curiel TJ. Tumor Intrinsic PD-L1 Promotes DNA Repair in Distinct Cancers and Suppresses PARP Inhibitor-Induced Synthetic Lethality. Cancer Res 2022; 82:2156-2170. [PMID: 35247877 PMCID: PMC9987177 DOI: 10.1158/0008-5472.can-21-2076] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 11/10/2021] [Accepted: 02/16/2022] [Indexed: 11/16/2022]
Abstract
BRCA1-mediated homologous recombination is an important DNA repair mechanism that is the target of FDA-approved PARP inhibitors, yet details of BRCA1-mediated functions remain to be fully elucidated. Similarly, immune checkpoint molecules are targets of FDA-approved cancer immunotherapies, but the biological and mechanistic consequences of their application are incompletely understood. We show here that the immune checkpoint molecule PD-L1 regulates homologous recombination in cancer cells by promoting BRCA1 nuclear foci formation and DNA end resection. Genetic depletion of tumor PD-L1 reduced homologous recombination, increased nonhomologous end joining, and elicited synthetic lethality to PARP inhibitors olaparib and talazoparib in vitro in some, but not all, BRCA1 wild-type tumor cells. In vivo, genetic depletion of tumor PD-L1 rendered olaparib-resistant tumors sensitive to olaparib. In contrast, anti-PD-L1 immune checkpoint blockade neither enhanced olaparib synthetic lethality nor improved its efficacy in vitro or in wild-type mice. Tumor PD-L1 did not alter expression of BRCA1 or its cofactor BARD1 but instead coimmunoprecipitated with BARD1 and increased BRCA1 nuclear accumulation. Tumor PD-L1 depletion enhanced tumor CCL5 expression and TANK-binding kinase 1 activation in vitro, similar to known immune-potentiating effects of PARP inhibitors. Collectively, these data define immune-dependent and immune-independent effects of PARP inhibitor treatment and genetic tumor PD-L1 depletion. Moreover, they implicate a tumor cell-intrinsic, immune checkpoint-independent function of PD-L1 in cancer cell BRCA1-mediated DNA damage repair with translational potential, including as a treatment response biomarker. SIGNIFICANCE PD-L1 upregulates BRCA1-mediated homologous recombination, and PD-L1-deficient tumors exhibit BRCAness by manifesting synthetic lethality in response to PARP inhibitors, revealing an exploitable therapeutic vulnerability and a candidate treatment response biomarker. See related commentary by Hanks, p. 2069.
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Affiliation(s)
- Anand V.R Kornepati
- Graduate School of Biomedical Science, University of Texas Health, San Antonio, Texas
| | - Jacob T. Boyd
- Graduate School of Biomedical Science, University of Texas Health, San Antonio, Texas
| | - Clare E. Murray
- Graduate School of Biomedical Science, University of Texas Health, San Antonio, Texas
| | | | | | - Cody M. Rogers
- Department of Biochemistry and Structural Biology, University of Texas Health, San Antonio, Texas
| | - Haiyan Bai
- Department of Medicine, University of Texas Health, San Antonio, Texas
| | - Alvaro S. Padron
- Department of Medicine, University of Texas Health, San Antonio, Texas
| | - Yiji Liao
- Department of Medicine, University of Texas Health, San Antonio, Texas
| | - Carlos Ontiveros
- Graduate School of Biomedical Science, University of Texas Health, San Antonio, Texas
| | - Robert S. Svatek
- Department of Biochemistry and Structural Biology, University of Texas Health, San Antonio, Texas
| | - Robert Hromas
- Department of Medicine, University of Texas Health, San Antonio, Texas
- UT Health Mays Cancer Center, University of Texas Health, San Antonio, Texas
| | - Rong Li
- Department of Medicine, University of Texas Health, San Antonio, Texas
- Department of Molecular Medicine, University of Texas Health, San Antonio, Texas
| | - Yanfen Hu
- Department of Medicine, University of Texas Health, San Antonio, Texas
- Department of Molecular Medicine, University of Texas Health, San Antonio, Texas
| | | | | | - Weixing Zhao
- Department of Biochemistry and Structural Biology, University of Texas Health, San Antonio, Texas
| | - Eloïse Dray
- Department of Biochemistry and Structural Biology, University of Texas Health, San Antonio, Texas
| | - Patrick Sung
- Department of Biochemistry and Structural Biology, University of Texas Health, San Antonio, Texas
| | - Tyler J. Curiel
- Graduate School of Biomedical Science, University of Texas Health, San Antonio, Texas
- Department of Medicine, University of Texas Health, San Antonio, Texas
- UT Health Mays Cancer Center, University of Texas Health, San Antonio, Texas
- to whom correspondence should addressed, STRF MC 8252, 8403 Floyd Curl Drive, San Antonio, TX, 78229. Phone: 210-562-4083; Fax: 210-450-1234, Corresponding author contact information: Tyler Curiel, MD, MPH, 8403 Floyd Curl Drive MC 8252, San Antonio, TX 78229, Telephone: 210-288-6446 33 Fax: 210-562-4084
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Shaverdian N, Shepherd AF, Li X, Offin M, Lengel HB, Gelblum DY, Wu AJ, Simone CB 2nd, Rimner A, Jones DR, Chaft JE, Riaz N, Gomez DR. Effects of Tumor Mutational Burden and Gene Alterations Associated with Radiation Response on Outcomes of Postoperative Radiation Therapy in Non-Small Cell Lung Cancer. Int J Radiat Oncol Biol Phys 2022; 113:335-44. [PMID: 35157996 DOI: 10.1016/j.ijrobp.2022.02.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 01/31/2022] [Accepted: 02/06/2022] [Indexed: 01/19/2023]
Abstract
PURPOSE Postoperative radiation therapy (PORT) in resected non-small cell lung cancer (NSCLC) improves locoregional outcomes, but recent randomized data do not support its unselected use. We assessed if tumor mutational burden (TMB) and mutations in genes associated with radiation sensitivity can select patients for PORT. METHODS AND MATERIALS Patients with resected NSCLC treated with and without PORT who underwent tumor genomic profiling were examined. The incidence of locoregional failures (LRFs) in patients with deleterious mutations in DNA damage response and repair (DDR) genes and genes associated with radiation resistance (KEAP1/NFE2L2/STK11/PIK3CA) were investigated. Cox modeling and receiver operating characteristic curve (ROC) analysis assessed the relationship between TMB and locoregional control (LRC). RESULTS Eighty-nine patients with NSCLC treated with PORT were analyzed, with a 2-year LRF rate of 19% (95% confidence interval, 10%-27%). Among patients treated with PORT, those with mutations in radiation resistance genes (n = 16 [18%]) had significantly more LRFs than patients without mutations (2-year LRF rate: 60% vs 11%; P < .001). On multivariate analysis, radiation-resistance mutations were associated with LRF after PORT (hazard ratio, 7.42; P < .001). Patients with mutations identified in DDR genes (n = 15 [17%]) had significantly improved LRC (P = .048) and no LRF events after PORT. On multivariate analysis, a higher TMB was associated with improved LRC after PORT (hazard ratio, 0.86; P = .01), and TMB was associated with PORT outcomes (area under ROC curve, 0.67-0.77). These genomic markers were not similarly associated with LRF in patients not treated with PORT. CONCLUSIONS The data suggest that patients with radiation-resistance gene alterations may derive minimal benefit from PORT, whereas patients with high TMB and/or alterations in DDR genes may benefit from PORT and be suited for future precision-RT strategies. Prospective studies are necessary to validate these findings.
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Abstract
PURPOSE OF REVIEW comprehensive molecular characterization of adrenocortical carcinoma (ACC) through next-generation sequencing and bioinformatics analyses is expanding the number of targets with potential prognostic and therapeutic value. We performed a critical review of recent published literature on genotyping of ACC. RECENT FINDINGS 423 studies were published between 2019 and 2021. After manual curation we summarized selected evidence in two thematic areas: germline deoxyribonucleic acid (DNA) variations, genomic alterations and prognosis. SUMMARY the evolving genomic landscape of ACC requires target validation in terms of prognostic and predictive value within scientific consortia. Although the existing multiple driver genes are difficult targets in the perspective of precision oncology, alterations in DNA damage repair genes or in promoter hypermethylation could open new venues for repurposing of existing drugs in ACC.
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Affiliation(s)
- Salvatore Grisanti
- Medical Oncology Unit, Department of Medical and Surgical Specialties, Radiological Sciences, and Public Health, University of Brescia, ASST Spedali Civili
| | - Deborah Cosentini
- Medical Oncology Unit, Department of Medical and Surgical Specialties, Radiological Sciences, and Public Health, University of Brescia, ASST Spedali Civili
| | - Sandra Sigala
- Section of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Alfredo Berruti
- Medical Oncology Unit, Department of Medical and Surgical Specialties, Radiological Sciences, and Public Health, University of Brescia, ASST Spedali Civili
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10
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Abstract
ABSTRACT Despite representing only 5% of all annual cancer diagnoses in the United States, pancreatic cancer is projected to become the second leading cause of cancer-related death within the next 10 years. Progress in the treatment of advanced pancreatic cancer has been slow. Systemic therapies rely on combination cytotoxic agents, with limited options at progression. Recently, poly(ADP-ribose) polymerase inhibitors have demonstrated clinical activity in patients with advanced pancreatic cancer and pathogenic variants in BRCA1, BRCA2, and PALB2. In this review, we discuss the development of poly(ADP-ribose) polymerase inhibitors in pancreatic cancer, relevant clinical trials, and future directions.
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Affiliation(s)
- Timothy J Brown
- Abramson Cancer Center, The University of Pennsylvania, Philadelphia, PA 19121
| | - Kim A Reiss
- Abramson Cancer Center, The University of Pennsylvania, Philadelphia, PA 19121
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11
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Anurag M, Punturi N, Hoog J, Bainbridge MN, Ellis MJ, Haricharan S. Comprehensive Profiling of DNA Repair Defects in Breast Cancer Identifies a Novel Class of Endocrine Therapy Resistance Drivers. Clin Cancer Res 2018; 24:4887-4899. [PMID: 29793947 PMCID: PMC6822623 DOI: 10.1158/1078-0432.ccr-17-3702] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 04/30/2018] [Accepted: 05/18/2018] [Indexed: 12/20/2022]
Abstract
Purpose: This study was undertaken to conduct a comprehensive investigation of the role of DNA damage repair (DDR) defects in poor outcome ER+ disease.Experimental Design: Expression and mutational status of DDR genes in ER+ breast tumors were correlated with proliferative response in neoadjuvant aromatase inhibitor therapy trials (discovery dataset), with outcomes in METABRIC, TCGA, and Loi datasets (validation datasets), and in patient-derived xenografts. A causal relationship between candidate DDR genes and endocrine treatment response, and the underlying mechanism, was then tested in ER+ breast cancer cell lines.Results: Correlations between loss of expression of three genes: CETN2 (P < 0.001) and ERCC1 (P = 0.01) from the nucleotide excision repair (NER) and NEIL2 (P = 0.04) from the base excision repair (BER) pathways were associated with endocrine treatment resistance in discovery dataset, and subsequently validated in independent patient cohorts. Complementary mutation analysis supported associations between mutations in NER and BER genes and reduced endocrine treatment response. A causal role for CETN2, NEIL2, and ERCC1 loss in intrinsic endocrine resistance was experimentally validated in ER+ breast cancer cell lines, and in ER+ patient-derived xenograft models. Loss of CETN2, NEIL2, or ERCC1 induced endocrine treatment resistance by dysregulating G1-S transition, and therefore, increased sensitivity to CDK4/6 inhibitors. A combined DDR signature score was developed that predicted poor outcome in multiple patient cohorts.Conclusions: This report identifies DDR defects as a new class of endocrine treatment resistance drivers and indicates new avenues for predicting efficacy of CDK4/6 inhibition in the adjuvant treatment setting. Clin Cancer Res; 24(19); 4887-99. ©2018 AACR.
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Affiliation(s)
- Meenakshi Anurag
- Department of Medicine, Baylor College of Medicine, Houston, Texas
- Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, Texas
| | - Nindo Punturi
- Department of Medicine, Baylor College of Medicine, Houston, Texas
- Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, Texas
| | - Jeremy Hoog
- Siteman Cancer Center Breast Cancer Program, Washington University School of Medicine, St. Louis, Missouri
| | - Matthew N Bainbridge
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
- Rady Children's Institute for Genomic Medicine, San Diego, California
| | - Matthew J Ellis
- Department of Medicine, Baylor College of Medicine, Houston, Texas.
- Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, Texas
| | - Svasti Haricharan
- Department of Medicine, Baylor College of Medicine, Houston, Texas.
- Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, Texas
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12
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Abstract
PURPOSE OF REVIEW The article presents the rationale, clinical development, and current status of poly (ADP ribose) polymerase inhibitors (PARPis) as anticancer agents. RECENT FINDINGS The recent approval of olaparib in heavily pretreated patients with advanced ovarian cancer carrying a BRCA1/2 mutation represents a significant therapeutic advance for patients with this difficult to treat disease. Though olaparib is the first agent in this class to be approved, multiple PARPis are in various stages of clinical development, including in combination with other treatment modalities such as radiation, antiangiogenic agents, and cytotoxic chemotherapies. SUMMARY Clinical benefit has been observed with PARPis in patients with advanced BRCA1/2 mutant ovarian and breast cancers. Various PARPis, either as single agents or in combination, are being evaluated in the neoadjuvant, adjuvant, and metastatic settings.
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Affiliation(s)
| | - Alice Chen
- National Cancer Institute, National Institutes of Health, Bethesda, MD
| | - Shivaani Kummar
- Division of Medical Oncology, Department of Medicine, Stanford University, Stanford, CA
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13
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Kummar S, Oza AM, Fleming GF, Sullivan DM, Gandara DR, Naughton MJ, Villalona-Calero MA, Morgan RJ, Szabo PM, Youn A, Chen AP, Ji J, Allen DE, Lih CJ, Mehaffey MG, Walsh WD, McGregor PM, Steinberg SM, Williams PM, Kinders RJ, Conley BA, Simon RM, Doroshow JH. Randomized Trial of Oral Cyclophosphamide and Veliparib in High-Grade Serous Ovarian, Primary Peritoneal, or Fallopian Tube Cancers, or BRCA-Mutant Ovarian Cancer. Clin Cancer Res 2015; 21:1574-82. [PMID: 25589624 PMCID: PMC4383665 DOI: 10.1158/1078-0432.ccr-14-2565] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 01/07/2015] [Indexed: 11/16/2022]
Abstract
PURPOSE Veliparib, a PARP inhibitor, demonstrated clinical activity in combination with oral cyclophosphamide in patients with BRCA-mutant solid tumors in a phase I trial. To define the relative contribution of PARP inhibition to the observed clinical activity, we conducted a randomized phase II trial to determine the response rate of veliparib in combination with cyclophosphamide compared with cyclophosphamide alone in patients with pretreated BRCA-mutant ovarian cancer or in patients with pretreated primary peritoneal, fallopian tube, or high-grade serous ovarian cancers (HGSOC). EXPERIMENTAL DESIGN Adult patients were randomized to receive cyclophosphamide alone (50 mg orally once daily) or with veliparib (60 mg orally once daily) in 21-day cycles. Crossover to the combination was allowed at disease progression. RESULTS Seventy-five patients were enrolled and 72 were evaluable for response; 38 received cyclophosphamide alone and 37 the combination as their initial treatment regimen. Treatment was well tolerated. One complete response was observed in each arm, with three partial responses (PR) in the combination arm and six PRs in the cyclophosphamide alone arm. Genetic sequence and expression analyses were performed for 211 genes involved in DNA repair; none of the detected genetic alterations were significantly associated with treatment benefit. CONCLUSION This is the first trial that evaluated single-agent, low-dose cyclophosphamide in HGSOC, peritoneal, fallopian tube, and BRCA-mutant ovarian cancers. It was well tolerated and clinical activity was observed; the addition of veliparib at 60 mg daily did not improve either the response rate or the median progression-free survival.
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Affiliation(s)
- Shivaani Kummar
- National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Amit M Oza
- Princess Margaret Hospital, University of Toronto, Ontario, Canada
| | - Gini F Fleming
- The University of Chicago Medical Center, Chicago, Illinois
| | | | - David R Gandara
- University of California Davis Cancer Center, Davis, California
| | | | - Miguel A Villalona-Calero
- The Ohio State University Comprehensive Cancer Center, James Cancer Hospital and Solove Research Institute, Columbus, Ohio
| | - Robert J Morgan
- City of Hope Comprehensive Cancer Center, Duarte, California
| | - Peter M Szabo
- National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Ahrim Youn
- National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Alice P Chen
- National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Jiuping Ji
- Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland
| | - Deborah E Allen
- National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Chih-Jian Lih
- Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland
| | - Michele G Mehaffey
- Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland
| | - William D Walsh
- Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland
| | - Paul M McGregor
- Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland
| | - Seth M Steinberg
- National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - P Mickey Williams
- Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland
| | - Robert J Kinders
- Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland
| | - Barbara A Conley
- National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Richard M Simon
- National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - James H Doroshow
- National Cancer Institute, National Institutes of Health, Bethesda, Maryland.
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14
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Cellini F, Morganti AG, Genovesi D, Silvestris N, Valentini V. Role of microRNA in response to ionizing radiations: evidences and potential impact on clinical practice for radiotherapy. Molecules 2014; 19:5379-401. [PMID: 24879584 PMCID: PMC6271831 DOI: 10.3390/molecules19045379] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 04/17/2014] [Accepted: 04/23/2014] [Indexed: 01/06/2023] Open
Abstract
MicroRNAs (miRNA) are small, non-coding, RNAs with gene expression regulator roles. As an important class of regulators of many cellular pathways, miRNAs are involved in many signaling pathways and DNA damage repair processes, affecting cellular radiosensitivity. Their role has led to interest in oncological implications to improve treatment results. MiRNAs represent a great opportunity to enhance the efficacy of radiotherapy treatments-they can be used to profile the radioresistance of tumors before radiotherapy, monitor their response throughout the treatment, thus helping to select intensification strategies, and also to define the final response to therapy along with risks of recurrence or metastatization. Even though many interesting studies support such potential, nowadays most studies on patient data are limited to experiments profiling tumor aggressiveness and response to radiotherapy. Moreover many studies report different although not conflicting results on the miRNAs evaluated for each tumor type. Without doubt, the clinical potential of such molecules for radiotherapy is striking and of high interest.
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Affiliation(s)
- Francesco Cellini
- Radiation Oncology Department, Policlinico Universitario Campus Bio-Medico; Via Álvaro del Portillo 200, 00144 Rome, Italy.
| | - Alessio G Morganti
- Radiotherapy Department, Università Cattolica del Sacro Cuore; Fondazione di Ricerca e Cura "Giovanni Paolo II", Largo Agostino Gemelli 1, 86100 Campobasso, Italy.
| | - Domenico Genovesi
- Radiation Oncology Department, Università "G. D'Annunzio"; Via dei Vestini 31, 66100 Chieti, Italy.
| | - Nicola Silvestris
- Medical Oncology Unit - Cancer Institute "Giovanni Paolo II"; Viale Orazio Flacco, 65, 70124 Bari, Italy.
| | - Vincenzo Valentini
- Radiation Oncology Department, Università Cattolica del Sacro Cuore; L.go Francesco Vito 1, 00168 Roma, Italy.
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15
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Abstract
An intricate network regulates the activities of SIRT1 and PARP1 proteins and continues to be uncovered. Both SIRT1 and PARP1 share a common co-factor nicotinamide adenine dinucleotide (NAD+) and several common substrates, including regulators of DNA damage response and circadian rhythms. We review this complex network using an interactive Molecular Interaction Map (MIM) to explore the interplay between these two proteins. Here we discuss how NAD + competition and post-transcriptional/translational feedback mechanisms create a regulatory network sensitive to environmental cues, such as genotoxic stress and metabolic states, and examine the role of those interactions in DNA repair and ultimately, cell fate decisions.
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Affiliation(s)
- Augustin Luna
- Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
- Bioinformatics Program, Boston University, Boston, MA 02215, USA
| | - Mirit I Aladjem
- Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Kurt W Kohn
- Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
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Bikle DD, Elalieh H, Welsh J, Oh D, Cleaver J, Teichert A. Protective role of vitamin D signaling in skin cancer formation. J Steroid Biochem Mol Biol 2013; 136:271-9. [PMID: 23059470 PMCID: PMC3596439 DOI: 10.1016/j.jsbmb.2012.09.021] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 09/18/2012] [Accepted: 09/19/2012] [Indexed: 12/26/2022]
Abstract
Vitamin D sufficiency is associated with protection against malignancy in a number of tissues clinically, and a strong body of evidence from animal and cell culture studies supports this protective role. Cancers in the skin differ, however, in that higher serum levels of 25OHD are associated with increased basal cell carcinomas (BCC), the most common form of epidermal malignancy. This result may be interpreted as indicating the role of UVR (spectrum 280-320) in producing vitamin D in the skin as well as causing those DNA mutations and proliferative changes that lead to epidermal malignancies. Recent animal studies have shown that mice lacking the vitamin D receptor (VDR) are predisposed to developing skin tumors either from chemical carcinogens such as 7,12-dimethylbenzanthracene (DMBA) or chronic UVR exposure. Such studies suggest that vitamin D production and subsequent signaling through the VDR in the skin may have evolved in part as a protective mechanism against UVR induced epidermal cancer formation. In this manuscript we provide evidence indicating that vitamin D signaling protects the skin from cancer formation by controlling keratinocyte proliferation and differentiation, facilitating DNA repair, and suppressing activation of the hedgehog (Hh) pathway following UVR exposure. This article is part of a Special Issue entitled 'Vitamin D Workshop'.
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Affiliation(s)
- Daniel D Bikle
- Department of Medicine, San Francisco VA Medical Center and University of California, San Francisco, CA, USA.
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17
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Nasto LA, Seo HY, Robinson AR, Tilstra JS, Clauson CL, Sowa GA, Ngo K, Dong Q, Pola E, Lee JY, Niedernhofer LJ, Kang JD, Robbins PD, Vo NV. ISSLS prize winner: inhibition of NF-κB activity ameliorates age-associated disc degeneration in a mouse model of accelerated aging. Spine (Phila Pa 1976) 2012; 37:1819-25. [PMID: 22343279 DOI: 10.1097/BRS.0b013e31824ee8f7] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN NF-κB activity was pharmacologically and genetically blocked in an accelerated aging mouse model to mitigate age-related disc degenerative changes. OBJECTIVE To study the mediatory role of NF-κB-signaling pathway in age-dependent intervertebral disc degeneration. SUMMARY OF BACKGROUND DATA Aging is a major contributor to intervertebral disc degeneration (IDD), but the molecular mechanism behind this process is poorly understood. NF-κB is a family of transcription factors that play a central role in mediating cellular response to damage, stress, and inflammation. Growing evidence implicates chronic NF-κB activation as a culprit in many aging-related diseases, but its role in aging-related IDD has not been adequately explored. We studied the effects of NF-κB inhibition on IDD, using a DNA repair-deficient mouse model of accelerated aging (Ercc1 mice) previously been reported to exhibit age-related IDD. METHODS Systemic inhibition of NF-κB activation was achieved either genetically by deletion of 1 allele of the NF-κB subunit p65 (Ercc1p65 mice) or pharmacologically by chronic intraperitoneal administration of the Nemo Binding Domain (8K-NBD) peptide to block the formation of the upstream activator of NF-κB, IκB Inducible Kinase (IKK), in Ercc1 mice. Disc cellularity, total proteoglycan content and proteoglycan synthesis of treated mice, and untreated controls were assessed. RESULTS.: Decreased disc matrix proteoglycan content, a hallmark feature of IDD, and elevated disc NF-κB activity were observed in discs of progeroid Ercc1 mice and naturally aged wild-type mice compared with young wild-type mice. Systemic inhibition of NF-κB by the 8K-NBD peptide in Ercc1 mice increased disc proteoglycan synthesis and ameriolated loss of disc cellularity and matrix proteoglycan. These results were confirmed genetically by using the p65 haploinsufficient Ercc1p65 mice. CONCLUSION These findings demonstrate that the IKK/NF-κB signaling pathway is a key mediator of age-dependent IDD and represents a therapeutic target for mitigating disc degenerative diseases associated with aging.
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Kou Y, Chang Y, Li X, Xiao J, Wang S. The rice RAD51C gene is required for the meiosis of both female and male gametocytes and the DNA repair of somatic cells. J Exp Bot 2012; 63:5323-35. [PMID: 22859673 PMCID: PMC3431001 DOI: 10.1093/jxb/ers190] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The RecA/RAD51 family of rice (Oryza sativa) consists of at least 13 members. However, the functions of most of these members are unknown. Here the functional characterization of one member of this family, RAD51C, is reported. Knockout (KO) of RAD51C resulted in both female and male sterility in rice. Transferring RAD51C to the RAD51C-KO line restored fertility. Cytological analyses showed that the sterility of RAD51C-KO plants was associated with abnormal early meiotic processes in both megasporocytes and pollen mother cells (PMCs). PMCs had an absence of normal pachytene chromosomes and had abnormal chromosome fragments. The RAD51C-KO line showed no obvious difference from wild-type plants in mitosis in the anther wall cells, which was consistent with the observation that the RAD51C-KO line did not have obviously abnormal morphology during vegetative development. However, the RAD51C-KO line was sensitive to different DNA-damaging agents. These results suggest that RAD51C is essential for reproductive development by regulating meiosis as well as for DNA damage repair in somatic cells.
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MESH Headings
- Agrobacterium/genetics
- Chromosomes, Plant/drug effects
- Chromosomes, Plant/metabolism
- Chromosomes, Plant/radiation effects
- DNA Fragmentation/drug effects
- DNA Fragmentation/radiation effects
- DNA Repair/drug effects
- DNA Repair/radiation effects
- DNA, Bacterial/genetics
- Gene Knockout Techniques
- Genes, Plant
- Genetic Complementation Test
- Germ Cells, Plant/drug effects
- Germ Cells, Plant/growth & development
- Germ Cells, Plant/radiation effects
- Meiosis/drug effects
- Meiosis/radiation effects
- Mitosis/drug effects
- Mitosis/radiation effects
- Molecular Sequence Data
- Mutagens/pharmacology
- Oryza/cytology
- Oryza/drug effects
- Oryza/genetics
- Oryza/growth & development
- Phylogeny
- Plant Infertility
- Plant Proteins/genetics
- Plant Proteins/metabolism
- Plants, Genetically Modified
- Pollen/drug effects
- Pollen/growth & development
- Pollen/radiation effects
- Rad51 Recombinase/genetics
- Rad51 Recombinase/metabolism
- Sequence Analysis, DNA
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Affiliation(s)
- Yanjun Kou
- National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan), Huazhong Agricultural UniversityWuhan 430070China
| | - Yuxiao Chang
- National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan), Huazhong Agricultural UniversityWuhan 430070China
| | - Xianghua Li
- National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan), Huazhong Agricultural UniversityWuhan 430070China
| | - Jinghua Xiao
- National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan), Huazhong Agricultural UniversityWuhan 430070China
| | - Shiping Wang
- National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan), Huazhong Agricultural UniversityWuhan 430070China
- To whom correspondence should be addressed. E-mail:
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Li X, Kaplun A, Lonardo F, Heath E, Sarkar FH, Irish J, Sakr W, Sheng S. HDAC1 inhibition by maspin abrogates epigenetic silencing of glutathione S-transferase pi in prostate carcinoma cells. Mol Cancer Res 2011; 9:733-45. [PMID: 21622623 PMCID: PMC3612175 DOI: 10.1158/1541-7786.mcr-10-0505] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Both maspin and glutathione S-transferase pi (GSTp) are implicated as tumor suppressors and downregulated in human prostate cancer. It is well established that GSTp downregulation is through DNA methylation-based silencing. We report here that maspin expression in prostate cancer cell line DU145 reversed GSTp DNA methylation, as measured by methylation- specific PCR, MethyLight assay, and bisulfite sequencing. The effect of maspin on GSTp expression was similar to that of the combination of a synthetic histone deacetylase (HDAC) inhibitor and DNA methylation inhibitor 5-aza-2'-deoxycytidine. Maspin expression also led to an increased level of acetylated histone 3, decreased level of methyl transferase, and methyl-CpG-binding domain proteins at the site of demethylated GSTp promoter DNA. Earlier, we have shown that maspin inhibits HDAC1. In PC3 cells, where both maspin and GSTp are expressed at a reduced level, maspin knockdown led to a significant reduction in GSTp expression, whereas dual knockdown of maspin and HDAC1 barely increased the level of GSTp expression. Thus, HDAC1 may play an essential role in cellular response to maspin-mediated GSTp desilencing. Maspin has been shown to increase tumor cell sensitivity to drug-induced apoptosis. Interestingly, GSTp reexpression in the absence of maspin expression perturbation blocked the phosphorylation of histone 2A.X, the induction of hypoxia-induced factor 1α (HIF-1α), and cell death of LNCaP cells under oxidative stress. Because DNA hypermethylation-based silencing may couple with and depend on histone deacetylation, our study suggests that endogenous HDAC inhibition by maspin may prevent pathologic gene silencing in prostate tumor progression.
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Affiliation(s)
- Xiaohua Li
- Department of Pathology, The Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, 540 East Canfield Avenue, Detroit, MI 48201
| | - Alexander Kaplun
- Department of Pathology, The Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, 540 East Canfield Avenue, Detroit, MI 48201
| | - Fulvio Lonardo
- Department of Pathology, The Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, 540 East Canfield Avenue, Detroit, MI 48201
| | - Elisabeth Heath
- Department of Internal Medicine, The Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, 540 East Canfield Avenue, Detroit, MI 48201
| | - Fazlul H. Sarkar
- Department of Pathology, The Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, 540 East Canfield Avenue, Detroit, MI 48201
| | - Jonathan Irish
- Department of Pathology, The Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, 540 East Canfield Avenue, Detroit, MI 48201
| | - Wael Sakr
- Department of Pathology, The Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, 540 East Canfield Avenue, Detroit, MI 48201
| | - Shijie Sheng
- Department of Pathology, The Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, 540 East Canfield Avenue, Detroit, MI 48201
- Address correspondence to: 313-993-4112 (Tel);313-993-4112 (Fax);
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Bogomazova AN, Lagarkova MA, Tskhovrebova LV, Shutova MV, Kiselev SL. Error-prone nonhomologous end joining repair operates in human pluripotent stem cells during late G2. Aging (Albany NY) 2011; 3:584-96. [PMID: 21685510 PMCID: PMC3164367 DOI: 10.18632/aging.100336] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Genome stability of human embryonic stem cells (hESC) is an important issue because even minor genetic alterations can negatively impact cell functionality and safety. The incorrect repair of DNA double-stranded breaks (DSBs) is the ultimate cause of the formation of chromosomal aberrations. Using G2 radiosensitivity assay, we analyzed chromosomal aberrations in pluripotent stem cells and somatic cells. The chromatid exchange aberration rates in hESCs increased manifold 2 hours after irradiation as compared with their differentiated derivatives, but the frequency of radiation-induced chromatid breaks was similar. The rate of radiation-induced chromatid exchanges in hESCs and differentiated cells exhibited a quadratic dose response, revealing two-hit mechanism of exchange formation suggesting that a non-homologous end joining (NHEJ) repair may contribute to their formation. Inhibition of DNA-PK, a key NHEJ component, by NU7026 resulted in a significant decrease in radiation-induced chromatid exchanges in hESCs but not in somatic cells. In contrast, NU7026 treatment increased the frequency of radiation-induced breaks to a similar extent in pluripotent and somatic cells. Thus, DNA-PK dependent NHEJ efficiently participates in the elimination of radiation-induced chromatid breaks during the late G2 in both cell types and DNA-PK activity leads to a high level of misrejoining specifically in pluripotent cells.
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Machida K, McNamara G, Cheng KTH, Huang J, Wang CH, Comai L, Ou JHJ, Lai MMC. Hepatitis C virus inhibits DNA damage repair through reactive oxygen and nitrogen species and by interfering with the ATM-NBS1/Mre11/Rad50 DNA repair pathway in monocytes and hepatocytes. J Immunol 2010; 185:6985-98. [PMID: 20974981 PMCID: PMC3101474 DOI: 10.4049/jimmunol.1000618] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Hepatitis C virus (HCV) infection is associated with the development of hepatocellular carcinoma and putatively also non-Hodgkin's B cell lymphoma. In this study, we demonstrated that PBMCs obtained from HCV-infected patients showed frequent chromosomal aberrations and that HCV infection of B cells in vitro induced enhanced chromosomal breaks and sister chromatid exchanges. HCV infection hypersensitized cells to ionizing radiation and bleomycin and inhibited nonhomologous end-joining repair. The viral core and nonstructural protein 3 proteins were shown to be responsible for the inhibition of DNA repair, mediated by NO and reactive oxygen species. Stable expression of core protein induced frequent chromosome translocations in cultured cells and in transgenic mice. HCV core protein binds to the NBS1 protein and inhibits the formation of the Mre11/NBS1/Rad50 complex, thereby affecting ATM activation and inhibiting DNA binding of repair enzymes. Taken together, these data indicate that HCV infection inhibits multiple DNA repair processes to potentiate chromosome instability in both monocytes and hepatocytes. These effects may explain the oncogenicity and immunological perturbation of HCV infection.
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Affiliation(s)
- Keigo Machida
- Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.
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Wang RH, Sengupta K, Li C, Kim HS, Cao L, Xiao C, Kim S, Xu X, Zheng Y, Chilton B, Jia R, Zheng ZM, Appella E, Wang XW, Ried T, Deng CX. Impaired DNA damage response, genome instability, and tumorigenesis in SIRT1 mutant mice. Cancer Cell 2008; 14:312-23. [PMID: 18835033 PMCID: PMC2643030 DOI: 10.1016/j.ccr.2008.09.001] [Citation(s) in RCA: 606] [Impact Index Per Article: 37.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2008] [Revised: 06/13/2008] [Accepted: 09/04/2008] [Indexed: 01/05/2023]
Abstract
In lower eukaryotes, Sir2 serves as a histone deacetylase and is implicated in chromatin silencing, longevity, and genome stability. Here we mutated the Sirt1 gene, a homolog of yeast Sir2, in mice to study its function. We show that a majority of SIRT1 null embryos die between E9.5 and E14.5, displaying altered histone modification, impaired DNA damage response, and reduced ability to repair DNA damage. We demonstrate that Sirt1(+/-);p53(+/-) mice develop tumors in multiple tissues, whereas activation of SIRT1 by resveratrol treatment reduces tumorigenesis. Finally, we show that many human cancers exhibit reduced levels of SIRT1 compared to normal controls. Thus, SIRT1 may act as a tumor suppressor through its role in DNA damage response and genome integrity.
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MESH Headings
- Animals
- Anticarcinogenic Agents/pharmacology
- Cell Cycle/genetics
- Cell Transformation, Neoplastic/drug effects
- Cell Transformation, Neoplastic/genetics
- Cell Transformation, Neoplastic/metabolism
- Cell Transformation, Neoplastic/radiation effects
- Cells, Cultured
- Chromosomal Instability
- DNA Damage
- DNA Repair
- Down-Regulation
- Embryo, Mammalian/metabolism
- Embryo, Mammalian/pathology
- Female
- Gene Expression Regulation, Developmental
- Gene Expression Regulation, Neoplastic
- Genomic Instability
- Gestational Age
- Heterochromatin/metabolism
- Histones/metabolism
- Humans
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mitosis/genetics
- Mutation
- Neoplasms/enzymology
- Neoplasms/genetics
- Neoplasms/prevention & control
- Resveratrol
- Sirtuin 1
- Sirtuins/analysis
- Sirtuins/deficiency
- Sirtuins/genetics
- Sirtuins/metabolism
- Stilbenes/pharmacology
- Time Factors
- Tumor Suppressor Proteins/deficiency
- Tumor Suppressor Proteins/genetics
- Tumor Suppressor Proteins/metabolism
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Affiliation(s)
- Rui-Hong Wang
- Genetics of Development and Disease Branch, 10/9N105, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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Qin XJ, Hudson LG, Liu W, Timmins GS, Liu KJ. Low concentration of arsenite exacerbates UVR-induced DNA strand breaks by inhibiting PARP-1 activity. Toxicol Appl Pharmacol 2008; 232:41-50. [PMID: 18619636 PMCID: PMC2584354 DOI: 10.1016/j.taap.2008.05.019] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2008] [Revised: 05/15/2008] [Accepted: 05/16/2008] [Indexed: 11/23/2022]
Abstract
Epidemiological studies have associated arsenic exposure with many types of human cancers. Arsenic has also been shown to act as a co-carcinogen even at low concentrations. However, the precise mechanism of its co-carcinogenic action is unknown. Recent studies indicate that arsenic can interfere with DNA-repair processes. Poly(ADP-ribose) polymerase (PARP)-1 is a zinc-finger DNA-repair protein, which can promptly sense DNA strand breaks and initiate DNA-repair pathways. In the present study, we tested the hypothesis that low concentrations of arsenic could inhibit PAPR-1 activity and so exacerbate levels of ultraviolet radiation (UVR)-induced DNA strand breaks. HaCat cells were treated with arsenite and/or UVR, and then DNA strand breaks were assessed by comet assay. Low concentrations of arsenite (
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Affiliation(s)
- Xu-Jun Qin
- Program of Toxicology, College of Pharmacy, University of New Mexico, Albuquerque, New Mexico 87131-0001, USA
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24
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Abstract
Arsenic is a recognized human carcinogen, but the mechanism of carcinogenesis is not well understood. Oxidative stress and inhibition of DNA damage repair have been postulated as potential carcinogenic actions of arsenic. The present study tests the hypothesis that arsenite not only induces oxidative stress but also inhibits the activity of the DNA base excision repair protein, poly(ADP-ribose) polymerase-1 (PARP-1), leading to exacerbation of the oxidative DNA damage induced by arsenic. HaCat cells were treated with arsenite for 24 h before measuring 8-hydroxyl-2'-deoxyguanosine (8-OHdG), PARP-1 activity, and reactive oxygen species (ROS). Zinc supplementation and PARP-1 siRNA were used to increase or decrease, respectively, the PARP-1 protein's physiological function. At high concentrations (10 microM or higher), arsenite greatly induced oxidative DNA damage, as indicated by 8-OHdG formation. At lower concentrations (1 microM), arsenite did not produce detectable 8-OHdG, but was still able to effectively inhibit PARP-1 activity. Zinc supplementation reduced the formation of 8-OHdG, restored the PARP-1 activity inhibited by arsenite, but did not decrease ROS production. SiRNA knockdown of PARP-1 did not affect the 8-OHdG level induced by arsenic, while it greatly increased the 8-OHdG level produced by hydrogen peroxide indicating that PARP-1 is a molecular target of arsenite. Our findings demonstrate that in addition to inducing oxidative stress at higher concentrations, arsenite can also inhibit the function of a key DNA repair protein, PARP-1, even at very low concentrations, thus exacerbating the overall oxidative DNA damage produced by arsenite, and potentially, by other oxidants as well.
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Affiliation(s)
- Xu-Jun Qin
- Program of Toxicology, College of Pharmacy, University of New Mexico, Albuquerque, New Mexico, 87131, USA
- Department of Toxicology, The Fourth Military Medical University, Xi’an, Shaanxi, 710032, China
| | - Laurie G. Hudson
- Program of Toxicology, College of Pharmacy, University of New Mexico, Albuquerque, New Mexico, 87131, USA
| | - Wenlan Liu
- Program of Toxicology, College of Pharmacy, University of New Mexico, Albuquerque, New Mexico, 87131, USA
| | - Wei Ding
- Program of Toxicology, College of Pharmacy, University of New Mexico, Albuquerque, New Mexico, 87131, USA
| | - Karen L. Cooper
- Program of Toxicology, College of Pharmacy, University of New Mexico, Albuquerque, New Mexico, 87131, USA
| | - Ke Jian Liu
- Program of Toxicology, College of Pharmacy, University of New Mexico, Albuquerque, New Mexico, 87131, USA
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