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Lu H, Toyoda JH, Wise SS, Browning CL, Speer RM, Croom-Pérez TJ, Bolt A, Meaza I, Wise JP. A whale of a tale: whale cells evade the driving mechanism for hexavalent chromium-induced chromosome instability. Toxicol Sci 2024; 199:49-62. [PMID: 38539048 PMCID: PMC11057468 DOI: 10.1093/toxsci/kfae030] [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] [Indexed: 04/26/2024] Open
Abstract
Chromosome instability, a hallmark of lung cancer, is a driving mechanism for hexavalent chromium [Cr(VI)] carcinogenesis in humans. Cr(VI) induces structural and numerical chromosome instability in human lung cells by inducing DNA double-strand breaks and inhibiting homologous recombination repair and causing spindle assembly checkpoint (SAC) bypass and centrosome amplification. Great whales are long-lived species with long-term exposures to Cr(VI) and accumulate Cr in their tissue, but exhibit a low incidence of cancer. Data show Cr(VI) induces fewer chromosome aberrations in whale cells after acute Cr(VI) exposure suggesting whale cells can evade Cr(VI)-induced chromosome instability. However, it is unknown if whales can evade Cr(VI)-induced chromosome instability. Thus, we tested the hypothesis that whale cells resist Cr(VI)-induced loss of homologous recombination repair activity and increased SAC bypass and centrosome amplification. We found Cr(VI) induces similar amounts of DNA double-strand breaks after acute (24 h) and prolonged (120 h) exposures in whale lung cells, but does not inhibit homologous recombination repair, SAC bypass, or centrosome amplification, and does not induce chromosome instability. These data indicate whale lung cells resist Cr(VI)-induced chromosome instability, the major driver for Cr(VI) carcinogenesis at a cellular level, consistent with observations that whales are resistant to cancer.
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Affiliation(s)
- Haiyan Lu
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40292, USA
| | - Jennifer H Toyoda
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40292, USA
| | - Sandra S Wise
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40292, USA
| | - Cynthia L Browning
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40292, USA
| | - Rachel M Speer
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40292, USA
| | - Tayler J Croom-Pérez
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40292, USA
| | - Alicia Bolt
- Department of Pharmaceutical Sciences, College of Pharmacy, The University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - Idoia Meaza
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40292, USA
| | - John Pierce Wise
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40292, USA
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2
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Wise JTF, Lu H, Meaza I, Wise SS, Williams AR, Wise JY, Mason MD, Wise JP. Prolonged Particulate Hexavalent Chromium Exposure Induces DNA Double-Strand Breaks and Inhibits Homologous Recombination Repair in Primary Rodent Lung Cells. Biol Trace Elem Res 2024:10.1007/s12011-024-04136-1. [PMID: 38499919 DOI: 10.1007/s12011-024-04136-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 02/28/2024] [Indexed: 03/20/2024]
Abstract
Hexavalent chromium [Cr(VI)] is a known lung carcinogen and a driving mechanism in human lung cells for Cr(VI)-induced lung cancer is chromosome instability, caused by prolonged Cr(VI) exposure inducing DNA double-strand breaks, while simultaneously inhibiting the repair of these breaks. In North Atlantic right whales, Cr(VI) induces breaks but does not inhibit repair. It is unclear if this repair inhibition is specific to human lung cells or occurs in other species, as it has only been considered in humans and North Atlantic right whales. We evaluated these outcomes in rodent cells, as rodents are an experimental model for metal-induced lung carcinogenesis. We used a guinea pig lung fibroblast cell line, JH4 Clone 1, and rat lung fibroblasts. Cells were exposed to two different particulate Cr(VI) compounds, ranging from 0 to 0.5 ug/cm2, for 24 or 120 h and assessed for cytotoxicity, DNA double-strand breaks, and DNA double-strand break repair. Both particulate Cr(VI) compounds induced a concentration-dependent increase in cytotoxicity and DNA double-strand breaks after acute and prolonged exposures. Notably, while the repair of Cr(VI)-induced DNA double-strand breaks increased after acute exposure, the repair of these breaks was inhibited after prolonged exposure. These results are consistent with outcomes in human lung cells indicating rodent cells respond like human cells, while whale cells have a markedly different response.
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Affiliation(s)
- James T F Wise
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, 40292, USA
- Wise Laboratory of Nutritional Toxicology and Metabolism, School of Nutrition and Food Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA, 70803, USA
- School of Nutrition and Food Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA, 70803, USA
| | - Haiyan Lu
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, 40292, USA
| | - Idoia Meaza
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, 40292, USA
| | - Sandra S Wise
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, 40292, USA
| | - Aggie R Williams
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, 40292, USA
| | - Jamie Young Wise
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, 40292, USA
| | - Michael D Mason
- Department of Chemical and Biological Engineering and the Institute for Molecular Biophysics, University of Maine, Orono, ME, 04469, USA
| | - John Pierce Wise
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, 40292, USA.
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Randolph ME, Afifi M, Gorthi A, Weil R, Wilky BA, Weinreb J, Ciero P, Hoeve NT, van Diest PJ, Raman V, Bishop AJ, Loeb DM. RNA helicase DDX3 regulates RAD51 localization and DNA damage repair in Ewing sarcoma. iScience 2024; 27:108925. [PMID: 38323009 PMCID: PMC10844834 DOI: 10.1016/j.isci.2024.108925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 12/09/2023] [Accepted: 01/12/2024] [Indexed: 02/08/2024] Open
Abstract
We previously demonstrated that RNA helicase DDX3X (DDX3) can be a therapeutic target in Ewing sarcoma (EWS), but its role in EWS biology remains unclear. The present work demonstrates that DDX3 plays a unique role in DNA damage repair (DDR). We show that DDX3 interacts with several proteins involved in homologous recombination, including RAD51, RECQL1, RPA32, and XRCC2. In particular, DDX3 colocalizes with RAD51 and RNA:DNA hybrid structures in the cytoplasm of EWS cells. Inhibition of DDX3 RNA helicase activity increases cytoplasmic RNA:DNA hybrids, sequestering RAD51 in the cytoplasm, which impairs nuclear translocation of RAD51 to sites of double-stranded DNA breaks, thus increasing sensitivity of EWS to radiation treatment, both in vitro and in vivo. This discovery lays the foundation for exploring new therapeutic approaches directed at manipulating DDR protein localization in solid tumors.
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Affiliation(s)
- Matthew E. Randolph
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, USA
- Department of Pediatrics, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Marwa Afifi
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Aparna Gorthi
- Greehey Children’s Cancer Research Institute and Department of Cell Systems & Anatomy, UT Health San Antonio, San Antonio, TX, USA
| | - Rachel Weil
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Breelyn A. Wilky
- Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, MD, USA
| | - Joshua Weinreb
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Paul Ciero
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, USA
- Department of Pediatrics, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Natalie ter Hoeve
- Department of Pathology, University Medical Centre Utrecht, Utrecht, the Netherlands
| | - Paul J. van Diest
- Department of Pathology, University Medical Centre Utrecht, Utrecht, the Netherlands
| | - Venu Raman
- Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, MD, USA
- Department of Radiology, Johns Hopkins University, Baltimore, MD, USA
- Department of Pharmacology, Johns Hopkins University, Baltimore, MD, USA
| | - Alexander J.R. Bishop
- Greehey Children’s Cancer Research Institute and Department of Cell Systems & Anatomy, UT Health San Antonio, San Antonio, TX, USA
| | - David M. Loeb
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, USA
- Department of Pediatrics, Albert Einstein College of Medicine, Bronx, NY, USA
- Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, MD, USA
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Meaza I, Williams AR, Lu H, Kouokam JC, Toyoda JH, Croom-Perez TJ, Wise SS, Aboueissa AEM, Wise JP. Prolonged particulate hexavalent chromium exposure induces RAD51 foci inhibition and cytoplasmic accumulation in immortalized and primary human lung bronchial epithelial cells. Toxicol Appl Pharmacol 2023; 479:116711. [PMID: 37805091 PMCID: PMC10841504 DOI: 10.1016/j.taap.2023.116711] [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: 08/16/2023] [Revised: 10/04/2023] [Accepted: 10/04/2023] [Indexed: 10/09/2023]
Abstract
Hexavalent chromium [Cr(VI)] is a human lung carcinogen with widespread exposure risks. Cr(VI) causes DNA double strand breaks that if unrepaired, progress into chromosomal instability (CIN), a key driving outcome in Cr(VI)-induced tumors. The ability of Cr(VI) to cause DNA breaks and inhibit repair is poorly understood in human lung epithelial cells, which are extremely relevant since pathology data show Cr(VI)-induced tumors originate from bronchial epithelial cells. In the present study, we considered immortalized and primary human bronchial epithelial cells. Cells were treated with zinc chromate at concentrations ranging 0.05 to 0.4μg/cm2 for acute (24 h) and prolonged (120 h) exposures. DNA double strand breaks (DSBs) were measured by neutral comet assay and the status of homologous recombination repair, the main pathway to fix Cr(VI)-induced DSBs, was measured by RAD51 foci formation with immunofluorescence, RAD51 localization with confocal microscopy and sister chromatid exchanges. We found acute and prolonged Cr(VI) exposure induced DSBs. Acute exposure induced homologous recombination repair, but prolonged exposure inhibited it resulting in chromosome instability in immortalized and primary human bronchial epithelial cells.
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Affiliation(s)
- Idoia Meaza
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston Street, Building 55A, Room 1422, Louisville, KY 40292, United States of America
| | - Aggie R Williams
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston Street, Building 55A, Room 1422, Louisville, KY 40292, United States of America
| | - Haiyan Lu
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston Street, Building 55A, Room 1422, Louisville, KY 40292, United States of America
| | - J Calvin Kouokam
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston Street, Building 55A, Room 1422, Louisville, KY 40292, United States of America
| | - Jennifer H Toyoda
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston Street, Building 55A, Room 1422, Louisville, KY 40292, United States of America
| | - Tayler J Croom-Perez
- Burnett School of Biomedical Sciences, University of Central Florida College of Medicine, 6900 Lake Nona Blvd., Orlando, FL 32827, United States of America
| | - Sandra S Wise
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston Street, Building 55A, Room 1422, Louisville, KY 40292, United States of America
| | | | - John Pierce Wise
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston Street, Building 55A, Room 1422, Louisville, KY 40292, United States of America.
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5
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Murthy MK, Khandayataray P, Padhiary S, Samal D. A review on chromium health hazards and molecular mechanism of chromium bioremediation. REVIEWS ON ENVIRONMENTAL HEALTH 2023; 38:461-478. [PMID: 35537040 DOI: 10.1515/reveh-2021-0139] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 04/19/2022] [Indexed: 05/13/2023]
Abstract
Living beings have been devastated by environmental pollution, which has reached its peak. The disastrous pollution of the environment is in large part due to industrial wastes containing toxic pollutants. The widespread use of chromium (Cr (III)/Cr (VI)) in industries, especially tanneries, makes it one of the most dangerous environmental pollutants. Chromium pollution is widespread due to ineffective treatment methods. Bioremediation of chromium (Cr) using bacteria is very thoughtful due to its eco-friendly and cost-effective outcome. In order to counter chromium toxicity, bacteria have numerous mechanisms, such as the ability to absorb, reduce, efflux, or accumulate the metal. In this review article, we focused on chromium toxicity on human and environmental health as well as its bioremediation mechanism.
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Affiliation(s)
| | | | - Samprit Padhiary
- Department of Biotechnology, Academy of Management and Information Technology, Khordha, India
| | - Dibyaranjan Samal
- Department of Biotechnology, Academy of Management and Information Technology, Khordha, India
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6
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Haberland VMM, Magin S, Iliakis G, Hartwig A. Impact of Manganese and Chromate on Specific DNA Double-Strand Break Repair Pathways. Int J Mol Sci 2023; 24:10392. [PMID: 37373538 DOI: 10.3390/ijms241210392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 06/01/2023] [Accepted: 06/05/2023] [Indexed: 06/29/2023] Open
Abstract
Manganese is an essential trace element; nevertheless, on conditions of overload, it becomes toxic, with neurotoxicity being the main concern. Chromate is a well-known human carcinogen. The underlying mechanisms seem to be oxidative stress as well as direct DNA damage in the case of chromate, but also interactions with DNA repair systems in both cases. However, the impact of manganese and chromate on DNA double-strand break (DSB) repair pathways is largely unknown. In the present study, we examined the induction of DSB as well as the effect on specific DNA DSB repair mechanisms, namely homologous recombination (HR), non-homologous end joining (NHEJ), single strand annealing (SSA), and microhomology-mediated end joining (MMEJ). We applied DSB repair pathway-specific reporter cell lines, pulsed field gel electrophoresis as well as gene expression analysis, and investigated the binding of specific DNA repair proteins via immunoflourescence. While manganese did not seem to induce DNA DSB and had no impact on NHEJ and MMEJ, HR and SSA were inhibited. In the case of chromate, the induction of DSB was further supported. Regarding DSB repair, no inhibition was seen in the case of NHEJ and SSA, but HR was diminished and MMEJ was activated in a pronounced manner. The results indicate a specific inhibition of error-free HR by manganese and chromate, with a shift towards error-prone DSB repair mechanisms in both cases. These observations suggest the induction of genomic instability and may explain the microsatellite instability involved in chromate-induced carcinogenicity.
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Affiliation(s)
- Vivien M M Haberland
- Department of Food Chemistry and Toxicology, Institute for Applied Biosciences, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany
| | - Simon Magin
- Institute of Medical Radiation Biology, Medical School, University of Duisburg-Essen, 45122 Essen, Germany
| | - George Iliakis
- Institute of Medical Radiation Biology, Medical School, University of Duisburg-Essen, 45122 Essen, Germany
| | - Andrea Hartwig
- Department of Food Chemistry and Toxicology, Institute for Applied Biosciences, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany
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7
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Randolph ME, Afifi M, Gorthi A, Weil R, Wilky BA, Weinreb J, Ciero P, ter Hoeve N, van Diest PJ, Raman V, Bishop AJR, Loeb DM. RNA Helicase DDX3 Regulates RAD51 Localization and DNA Damage Repair in Ewing Sarcoma. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.10.544474. [PMID: 37333164 PMCID: PMC10274875 DOI: 10.1101/2023.06.10.544474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
We previously demonstrated that RNA helicase DDX3X (DDX3) can be a therapeutic target in Ewing sarcoma (EWS), but its role in EWS biology remains unclear. The present work demonstrates that DDX3 plays a unique role in DNA damage repair (DDR). We show that DDX3 interacts with several proteins involved in homologous recombination, including RAD51, RECQL1, RPA32, and XRCC2. In particular, DDX3 colocalizes with RAD51 and RNA:DNA hybrid structures in the cytoplasm of EWS cells. Inhibition of DDX3 RNA helicase activity increases cytoplasmic RNA:DNA hybrids, sequestering RAD51 in the cytoplasm, which impairs nuclear translocation of RAD51 to sites of double-stranded DNA breaks thus increasing sensitivity of EWS to radiation treatment, both in vitro and in vivo. This discovery lays the foundation for exploring new therapeutic approaches directed at manipulating DDR protein localization in solid tumors.
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Affiliation(s)
- Matthew E. Randolph
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY
- Department of Pediatrics, Albert Einstein College of Medicine, Bronx, NY
| | - Marwa Afifi
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, MD
| | - Aparna Gorthi
- Greehey Children’s Cancer Research Institute and Department of Cell Systems & Anatomy, UT Health San Antonio, San Antonio, TX
| | - Rachel Weil
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY
| | - Breelyn A. Wilky
- Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, MD
| | - Joshua Weinreb
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY
| | - Paul Ciero
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY
- Department of Pediatrics, Albert Einstein College of Medicine, Bronx, NY
| | - Natalie ter Hoeve
- Department of Pathology, University Medical Centre Utrecht, The Netherlands
| | - Paul J. van Diest
- Department of Pathology, University Medical Centre Utrecht, The Netherlands
| | - Venu Raman
- Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, MD
- Department of Radiology, Johns Hopkins University, Baltimore, MD
- Department of Pharmacology, Johns Hopkins University, Baltimore, MD
| | - Alexander J. R. Bishop
- Greehey Children’s Cancer Research Institute and Department of Cell Systems & Anatomy, UT Health San Antonio, San Antonio, TX
| | - David M. Loeb
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY
- Department of Pediatrics, Albert Einstein College of Medicine, Bronx, NY
- Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, MD
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8
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Wise SS, Lu H, Speer RM, Wise JP, Young J, Toyoda JH, Meaza I, Croom-Perez TJ, Kouokam JC, Specht A, Liu KJ, Hoyle GW, Wise JP. Chromium distribution in an oropharyngeal aspiration model for hexavalent chromium in rats. Toxicol Appl Pharmacol 2022; 457:116294. [PMID: 36283442 PMCID: PMC10121970 DOI: 10.1016/j.taap.2022.116294] [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: 07/22/2022] [Revised: 10/05/2022] [Accepted: 10/19/2022] [Indexed: 11/06/2022]
Abstract
Hexavalent chromium [Cr(VI)] is a well-known and widespread environmental contaminant associated with a variety of adverse health effects, in particular lung cancer. The primary route of exposure in humans is through inhalation. Particulate forms of Cr(VI) are the most potent but in vivo studies are difficult. Intratracheal instillation requires highly trained surgical procedures which also limits the number of repeated exposures possible and thus requires high doses. Inhalation studies can deliver lower more chronic doses but are expensive and generate dangerous aerosols. We evaluated an oropharyngeal aspiration exposure route for zinc chromate particles in Wistar rats. Animals were treated once per week for 90 days. We found chromium accumulated in the lungs, blood, and reproductive tissues of all treated animals. Additionally, we found inflammatory indicators in the lung were elevated and circulating lymphocytes had increased chromosomal damage. These results show oropharyngeal aspiration provides a practicable exposure route for chronic and sub-chronic exposures of Cr(VI) particles.
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Affiliation(s)
- Sandra S Wise
- Wise Laboratory of Environmental and Genetic Toxicology, University of Louisville, 500 S. Preston St, HSC55A Rm 1422, United States of America; Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, United States of America
| | - Haiyan Lu
- Wise Laboratory of Environmental and Genetic Toxicology, University of Louisville, 500 S. Preston St, HSC55A Rm 1422, United States of America; Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, United States of America
| | - Rachel M Speer
- Wise Laboratory of Environmental and Genetic Toxicology, University of Louisville, 500 S. Preston St, HSC55A Rm 1422, United States of America; Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, United States of America; Department of Pharmaceutical Sciences, University of New Mexico, Albuquerque, NM, United States of America
| | - John Pierce Wise
- Pediatric Research Institute, Department of Pediatrics, University of Louisville, Louisville, KY, United States of America
| | - Jamie Young
- Wise Laboratory of Environmental and Genetic Toxicology, University of Louisville, 500 S. Preston St, HSC55A Rm 1422, United States of America; Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, United States of America
| | - Jennifer H Toyoda
- Wise Laboratory of Environmental and Genetic Toxicology, University of Louisville, 500 S. Preston St, HSC55A Rm 1422, United States of America; Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, United States of America
| | - Idoia Meaza
- Wise Laboratory of Environmental and Genetic Toxicology, University of Louisville, 500 S. Preston St, HSC55A Rm 1422, United States of America; Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, United States of America
| | - Tayler J Croom-Perez
- Wise Laboratory of Environmental and Genetic Toxicology, University of Louisville, 500 S. Preston St, HSC55A Rm 1422, United States of America; Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, United States of America
| | - J Calvin Kouokam
- Wise Laboratory of Environmental and Genetic Toxicology, University of Louisville, 500 S. Preston St, HSC55A Rm 1422, United States of America; Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, United States of America
| | - Aaron Specht
- School of Health Sciences, Purdue University, West Lafayette, IN, United States of America
| | - Ke Jian Liu
- Department of Pharmaceutical Sciences, University of New Mexico, Albuquerque, NM, United States of America
| | - Gary W Hoyle
- Department of Environmental and Occupational Health, School of Public Health and Information Sciences University of Louisville, Louisville, KY, United States of America
| | - John Pierce Wise
- Wise Laboratory of Environmental and Genetic Toxicology, University of Louisville, 500 S. Preston St, HSC55A Rm 1422, United States of America; Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, United States of America.
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Speer RM, Meaza I, Toyoda JH, Lu Y, Xu Q, Walter RB, Kong M, Lu H, Kouokam JC, Wise JP. Particulate hexavalent chromium alters microRNAs in human lung cells that target key carcinogenic pathways. Toxicol Appl Pharmacol 2022; 438:115890. [PMID: 35101437 PMCID: PMC8938933 DOI: 10.1016/j.taap.2022.115890] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 12/20/2021] [Accepted: 01/17/2022] [Indexed: 10/19/2022]
Abstract
Hexavalent chromium [Cr(VI)] is a global environmental pollutant and human lung carcinogen. However, the mechanisms of Cr(VI) carcinogenesis are not well defined. Cr(VI)-altered gene expression has been reported in the literature and is implicated in numerous mechanisms of Cr(VI) carcinogenesis. MicroRNAs (miRNAs) play a key role in controlling gene expression and are associated with carcinogenic mechanisms. To date no studies have evaluated global changes in miRNA expression in human cells after Cr(VI) exposure. We used RNA sequencing to evaluate how a particulate Cr(VI) compound (zinc chromate), the most potent form of Cr(VI), alters global miRNA expression after acute (24 h) or prolonged (72 and 120 h) exposure to 0.1, 0.2 and 0.3 μg/cm2 zinc chromate in an immortalized, non-cancerous human lung cell line (WTHBF-6). Particulate Cr(VI) significantly affected expression of miRNAs at all time points and concentrations tested. We also found the number of significantly downregulated miRNAs increased in a time- and concentration-dependent manner and many miRNAs were upregulated after 24 h exposure at the intermediate concentration tested. Pathway analyses of the differentially expressed miRNAs predicted miRNAs target pathways of Cr(VI) carcinogenesis in a time- and concentration-dependent manner. These data are the first to evaluate global changes in miRNA expression in human lung cells after Cr(VI) exposure and indicate miRNAs may play a key role in pathways of Cr(VI) carcinogenesis.
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Affiliation(s)
- Rachel M. Speer
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston St, Rm 1422, Louisville, KY, USA
| | - Idoia Meaza
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston St, Rm 1422, Louisville, KY, USA
| | - Jennifer H. Toyoda
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston St, Rm 1422, Louisville, KY, USA
| | - Yuan Lu
- Xiphophorus Genetic Stock Center, Texas State University, 601 University Dr. San Marcos, TX, USA
| | - Qian Xu
- Department of Bioinformatics and Biostatistics, University of Louisville, 485 E. Gray St., Louisville, KY, USA
| | - Ronald B. Walter
- Xiphophorus Genetic Stock Center, Texas State University, 601 University Dr. San Marcos, TX, USA
| | - Maiying Kong
- Department of Bioinformatics and Biostatistics, University of Louisville, 485 E. Gray St., Louisville, KY, USA
| | - Haiyan Lu
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston St, Rm 1422, Louisville, KY, USA
| | - J. Calvin Kouokam
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston St, Rm 1422, Louisville, KY, USA
| | - John Pierce Wise
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston St, Rm 1422, Louisville, KY, USA.
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Wise JP, Young JL, Cai J, Cai L. Current understanding of hexavalent chromium [Cr(VI)] neurotoxicity and new perspectives. ENVIRONMENT INTERNATIONAL 2022; 158:106877. [PMID: 34547640 PMCID: PMC8694118 DOI: 10.1016/j.envint.2021.106877] [Citation(s) in RCA: 68] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 09/08/2021] [Accepted: 09/09/2021] [Indexed: 05/21/2023]
Abstract
Hexavalent chromium [Cr(VI)] is a global environmental pollutant that increases risk for several types of cancers and is increasingly being recognized as a neurotoxicant. Traditionally, the brain has been viewed as a largely post-mitotic organ due to its specialized composition of neurons, and consequently, clastogenic effects were not considered in neurotoxicology. Today, we understand the brain is composed of at least eight distinct cell types - most of which continue mitotic activity throughout lifespan. We have learned these dividing cells play essential roles in brain and body health. This review focuses on Cr(VI), a potent clastogen and known human carcinogen, as a potentially neurotoxic agent targeting mitotic cells of the brain. Despite its well-established role as a human carcinogen, Cr(VI) neurotoxicity studies have failed to find a significant link to brain cancers. In the few studies that did find a link, Cr(VI) was identified as a risk for gliomas. Instead, in the human brain, Cr(VI) appears to have more subtle deleterious effects that can impair childhood learning and attention development, olfactory function, social memory, and may contribute to motor neuron diseases. Studies of Cr(VI) neurotoxicity with animal and cell culture models have demonstrated elevated markers of oxidative damage and redox stress, with widespread neurodegeneration. One study showed mice exposed to Cr(VI)-laden tannery effluent exhibited longer periods of aggressive behavior toward an "intruder" mouse and took longer to recognize mice previously encountered, recapitulating the social memory deficits observed in humans. Here we conducted a critical review of the available literature on Cr(VI) neurotoxicity and synthesize the collective observations to thoroughly evaluate Cr(VI) neurotoxicity - much remains to be understood and recognized.
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Affiliation(s)
- John P Wise
- Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40292, USA; Pediatric Research Institute, The Department of Pediatrics, University of Louisville School of Medicine, Louisville, KY 40292, USA.
| | - Jamie L Young
- Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40292, USA; Pediatric Research Institute, The Department of Pediatrics, University of Louisville School of Medicine, Louisville, KY 40292, USA
| | - Jun Cai
- Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40292, USA; Pediatric Research Institute, The Department of Pediatrics, University of Louisville School of Medicine, Louisville, KY 40292, USA
| | - Lu Cai
- Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40292, USA; Pediatric Research Institute, The Department of Pediatrics, University of Louisville School of Medicine, Louisville, KY 40292, USA
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11
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Quezada-Maldonado EM, Sánchez-Pérez Y, Chirino YI, García-Cuellar CM. Airborne particulate matter induces oxidative damage, DNA adduct formation and alterations in DNA repair pathways. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 287:117313. [PMID: 34022687 DOI: 10.1016/j.envpol.2021.117313] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 04/12/2021] [Accepted: 05/02/2021] [Indexed: 06/12/2023]
Abstract
Air pollution, which includes particulate matter (PM), is classified in group 1 as a carcinogen to humans by the International Agency for Research in Cancer. Specifically, PM exposure has been associated with lung cancer in patients living in highly polluted cities. The precise mechanism by which PM is linked to cancer has not been completely described, and the genotoxicity induced by PM exposure plays a relevant role in cell damage. In this review, we aimed to analyze the types of DNA damage and alterations in DNA repair pathways induced by PM exposure, from both epidemiological and toxicological studies, to comprehend the contribution of PM exposure to carcinogenesis. Scientific evidence supports that PM exposure mainly causes oxidative stress by reactive oxygen species (ROS) and the formation of DNA adducts, specifically by polycyclic aromatic hydrocarbons (PAH). PM exposure also induces double-strand breaks (DSBs) and deregulates the expression of some proteins in DNA repair pathways, precisely, base and nucleotide excision repairs and homologous repair. Furthermore, specific polymorphisms of DNA repair genes could lead to an adverse response in subjects exposed to PM. Nevertheless, information about the effects of PM on DNA repair pathways is still limited, and it has not been possible to conclude which pathways are the most affected by exposure to PM or if DNA damage is repaired properly. Therefore, deepening the study of genotoxic damage and alterations of DNA repair pathways is needed for a more precise understanding of the carcinogenic mechanism of PM.
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Affiliation(s)
- Ericka Marel Quezada-Maldonado
- Subdirección de Investigación Básica, Instituto Nacional de Cancerología, San Fernando No. 22, Tlalpan, CP 14080, CDMX, Mexico; Programa de Doctorado en Ciencias Biomédicas, Universidad Nacional Autónoma de México, Unidad de Posgrado Edificio B, Primer Piso, Ciudad Universitaria, Coyoacán, CP 04510, Ciudad de México, Mexico
| | - Yesennia Sánchez-Pérez
- Subdirección de Investigación Básica, Instituto Nacional de Cancerología, San Fernando No. 22, Tlalpan, CP 14080, CDMX, Mexico
| | - Yolanda I Chirino
- Unidad de Biomedicina, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Los Reyes Iztacala, Tlalnepantla de Baz, CP 54090, Estado de México, Mexico
| | - Claudia M García-Cuellar
- Subdirección de Investigación Básica, Instituto Nacional de Cancerología, San Fernando No. 22, Tlalpan, CP 14080, CDMX, Mexico.
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Speer RM, Toyoda JH, Croom-Perez TJ, Liu KJ, Wise JP. Particulate Hexavalent Chromium Inhibits E2F1 Leading to Reduced RAD51 Nuclear Foci Formation in Human Lung Cells. Toxicol Sci 2021; 181:35-46. [PMID: 33677506 DOI: 10.1093/toxsci/kfab019] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Lung cancer is the leading cause of cancer death; however, the mechanisms of lung carcinogens are poorly understood. Metals, including hexavalent chromium [Cr(VI)], induce chromosome instability, an early event in lung cancer. Failure of homologous recombination repair is a key mechanism for chromosome instability. Particulate Cr(VI) causes DNA double-strand breaks and prolonged exposure impairs homologous recombination targeting a key effector protein in this pathway, RAD51. Reduced RAD51 protein is a key endpoint of particulate Cr(VI) exposure. It is currently unknown how Cr(VI) reduces RAD51 protein. E2F1 is the predominant transcription factor for RAD51. This study sought to identify if E2F1 modulates the RAD51 response to particulate Cr(VI). Particulate Cr(VI) reduced RAD51 protein and mRNA levels but had a minimal effect on RAD51 half-life. E2F1 protein and mRNA were also inhibited by particulate Cr(VI) exposure. To connect these two outcomes, we tested if modulating E2F1 affects RAD51 outcomes after particulate Cr(VI) exposure. E2F1 knockdown inhibited RAD51 nuclear foci formation after acute particulate Cr(VI) exposure. These data indicate reduced RAD51 protein levels after prolonged particulate Cr(VI) exposure are predominantly due to inhibited expression. Particulate Cr(VI) also inhibits E2F1 expression. However, although loss of E2F1 does not modulate RAD51 expression after particulate Cr(VI) exposure, RAD51 nuclear foci formation is inhibited. These findings suggest E2F1 is important for RAD51 localization to double-strand breaks, but not expression after particulate Cr(VI) exposure in human lung cells.
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Affiliation(s)
- Rachel M Speer
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40292, USA
| | - Jennifer H Toyoda
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40292, USA
| | - Tayler J Croom-Perez
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40292, USA
| | - Ke Jian Liu
- Department of Pharmaceutical Sciences, University of New Mexico, Albuquerque, New Mexico, USA
| | - John Pierce Wise
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40292, USA
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Atlı Şekeroğlu Z, Şekeroğlu V, Kontaş Yedier S, İlkun E, Liou LS. Increased DNA strand breaks and neoplastic transformation in human bladder cells treated with pioglitazone. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2021; 62:143-154. [PMID: 33496997 DOI: 10.1002/em.22424] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 01/19/2021] [Accepted: 01/22/2021] [Indexed: 06/12/2023]
Abstract
Pioglitazone (PIO), an oral hypoglycemic agent, is used in the treatment of type 2 diabetes. Some studies have suggested that an increased risk of bladder cancer with PIO exposure, while the others reported there is no such relationship. Therefore, it is doubtful whether PIO can increase the risk of bladder cancer. The effects of PIO on DNA damage and/or transformation of human bladder cells are not fully known. We investigated the effects of PIO on cytotoxicity, DNA single and double strand breaks and repair and neoplastic transformation in human bladder cells (hTU1) treated with 10, 20, and 40 μM PIO for 24, 48 and 72 hr. PIO decreased cell viability in a concentration-dependent manner. Increased levels of comet parameters showed that PIO and its metabolites can significantly induce DNA double strand breaks at all concentrations tested. PIO also significantly induced the formation of phosphorylated H2AX and p53 binding protein 1 foci. DNA damage was not repaired in a 24 hr recovery period. PIO can also induce malignant transformation of human bladder cells exhibiting loss of contact inhibition and anchorage independent growth. This is the first study to indicate that PIO can induce DNA damage and malignant transformation, reduce or alter the DNA repair capacity in human bladder cells. From these results, we suggest that patients with diabetes treated with PIO may have an increased risk of bladder cancer.
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Affiliation(s)
- Zülal Atlı Şekeroğlu
- Department of Molecular Biology and Genetics, Faculty of Science and Letters, Ordu University, Ordu, Turkey
| | - Vedat Şekeroğlu
- Department of Molecular Biology and Genetics, Faculty of Science and Letters, Ordu University, Ordu, Turkey
| | - Seval Kontaş Yedier
- Department of Molecular Biology and Genetics, Faculty of Science and Letters, Ordu University, Ordu, Turkey
| | - Emre İlkun
- Department of Molecular Biology and Genetics, Faculty of Science and Letters, Ordu University, Ordu, Turkey
| | - Louis S Liou
- Department of Urology, Cambridge Health Alliance, Cambridge, Massachusetts, USA
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VonHandorf A, Zablon HA, Biesiada J, Zhang X, Medvedovic M, Puga A. Hexavalent chromium promotes differential binding of CTCF to its cognate sites in Euchromatin. Epigenetics 2021; 16:1361-1376. [PMID: 33319643 DOI: 10.1080/15592294.2020.1864168] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Hexavalent chromium compounds are well-established respiratory carcinogens to which humans are commonly exposed in industrial and occupational settings. In addition, natural and anthropogenic sources of these compounds contribute to the exposure of global populations through multiple routes, including dermal, ingestion and inhalation that elevate the risk of cancer by largely unresolved mechanisms. Cr(VI) has genotoxic properties that include ternary adduct formation with DNA, increases in DNA damage, mostly by double-strand break formation, and altered transcriptional responses. Our previous work using ATAC-seq showed that CTCF motifs were enriched in Cr(VI)-dependent differentially accessible chromatin, suggesting that CTCF, a key transcription factor responsible for the regulation of the transcriptome, might be a chromium target. To test this hypothesis, we investigated the effect of Cr(VI) treatment on the binding of CTCF to its cognate sites and ensuing changes in transcription-related histone modifications. Differentially bound CTCF sites were enriched by Cr(VI) treatment within transcription-related regions, specifically transcription start sites and upstream genic regions. Functional annotation of the affected genes highlighted biological processes previously associated with Cr(VI) exposure. Notably, we found that differentially bound CTCF sites proximal to the promoters of this subset of genes were frequently associated with the active histone marks H3K27ac, H3K4me3, and H3K36me3, in agreement with the concept that Cr(VI) targets CTCF in euchromatic regions of the genome. Our results support the conclusion that Cr(VI) treatment promotes the differential binding of CTCF to its cognate sites in genes near transcription-active boundaries, targeting these genes for dysregulation.
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Affiliation(s)
- Andrew VonHandorf
- Department of Environmental and Public Health Sciences and Center for Environmental Genetics University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Hesbon A Zablon
- Department of Environmental and Public Health Sciences and Center for Environmental Genetics University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Jacek Biesiada
- Department of Environmental and Public Health Sciences and Center for Environmental Genetics University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Xiang Zhang
- Department of Environmental and Public Health Sciences and Center for Environmental Genetics University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Mario Medvedovic
- Department of Environmental and Public Health Sciences and Center for Environmental Genetics University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Alvaro Puga
- Department of Environmental and Public Health Sciences and Center for Environmental Genetics University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
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Chen Z, Zhong J, Ren X, Liu W, Wu D, Chen C, Huang H, Huang X, Liu Y, Liu J. Involvement of a novel regulatory cascade consisting of SET-H3K18ac/H3K27ac-53BP1 in Cr(VI)-induced malignant transformation of 16HBE cells. Toxicol Lett 2020; 339:70-77. [PMID: 33370592 DOI: 10.1016/j.toxlet.2020.12.017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 12/09/2020] [Accepted: 12/21/2020] [Indexed: 12/20/2022]
Abstract
Hexavalent chromium (Cr(VI)) is a well-established human carcinogen with DNA damaging effects. Recently we established a Cr(VI)-induced malignant transformation model from a human bronchial epithelial (16HBE) cell line, and in the transformed (16HBE-T) cells reduced levels of 53BP1 (critical for DNA repair) and the acetylated histone H3K18/27 (H3K18/27ac) were observed. In 16HBE-T cells SET (a multifunctional protein) was elevated by Cr(VI) through quantitative proteomics analysis. In the present study, we further explore the involvement of SET in the H3K18/27ac/53BP1 cascade in the 16HBE-T model, primarily by knockdown of SET. Bioinformatic analysis of the differentially expressed proteins indicated enrichment in histone modifications, in which SET was a major regulator. In 16HBE cells SET expression was enhanced by Cr(VI) in a concentration- and exposure duration-dependent manner. In 16HBE-T cells, SET knockdown showed the following effects: reversal of H3K18/27ac and 53BP1 levels, enhanced enrichment H3K18/27ac in 53BP1's promotor region, increase rate of apoptosis and cell cycle G0/G1 arrest (with or without Cr(VI) treatment), and reduced colony-forming efficiency. Finally, In comparison with benzo(a)pyrene-transformed (malignant, 16HBE-B) cells from 16HBE where no changes in H3K18/27ac, 53BP1 or SET were observed, while the H3K18/27ac/53BP1 cascade was downregulated and SET upregulated in 16HBE-T cells, as compared with the parental 16HBE cells; thus the changes in 16HBE-T might be a specific effect of Cr(VI). In conclusion, our results suggest that SET may be involved in the malignant cell transformation, through inhibiting the H3K18/27ac/53BP1 cascade, at least in the 16HBE cell model.
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Affiliation(s)
- Zhihong Chen
- Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou, China; Shenzhen Key Laboratory of Modern Toxicology, Shenzhen Medical Key Discipline of Health Toxicology (2020-2024), Shenzhen Center for Disease Control and Prevention, Shenzhen, China, 518055
| | - Jiacheng Zhong
- Shenzhen Key Laboratory of Modern Toxicology, Shenzhen Medical Key Discipline of Health Toxicology (2020-2024), Shenzhen Center for Disease Control and Prevention, Shenzhen, China, 518055
| | - Xiaohu Ren
- Shenzhen Key Laboratory of Modern Toxicology, Shenzhen Medical Key Discipline of Health Toxicology (2020-2024), Shenzhen Center for Disease Control and Prevention, Shenzhen, China, 518055
| | - Wei Liu
- Shenzhen Key Laboratory of Modern Toxicology, Shenzhen Medical Key Discipline of Health Toxicology (2020-2024), Shenzhen Center for Disease Control and Prevention, Shenzhen, China, 518055
| | - Desheng Wu
- Shenzhen Key Laboratory of Modern Toxicology, Shenzhen Medical Key Discipline of Health Toxicology (2020-2024), Shenzhen Center for Disease Control and Prevention, Shenzhen, China, 518055
| | - Chongyang Chen
- Shenzhen Key Laboratory of Modern Toxicology, Shenzhen Medical Key Discipline of Health Toxicology (2020-2024), Shenzhen Center for Disease Control and Prevention, Shenzhen, China, 518055
| | - Haiyan Huang
- Shenzhen Key Laboratory of Modern Toxicology, Shenzhen Medical Key Discipline of Health Toxicology (2020-2024), Shenzhen Center for Disease Control and Prevention, Shenzhen, China, 518055
| | - Xinfeng Huang
- Shenzhen Key Laboratory of Modern Toxicology, Shenzhen Medical Key Discipline of Health Toxicology (2020-2024), Shenzhen Center for Disease Control and Prevention, Shenzhen, China, 518055
| | - Yungang Liu
- Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou, China
| | - Jianjun Liu
- Department of Toxicology, School of Public Health, Southern Medical University, Guangzhou, China; Shenzhen Key Laboratory of Modern Toxicology, Shenzhen Medical Key Discipline of Health Toxicology (2020-2024), Shenzhen Center for Disease Control and Prevention, Shenzhen, China, 518055.
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Meaza I, Speer RM, Toyoda JH, Lu H, Wise SS, Croom-Perez TJ, Aboueissa AEM, Wise JP. Prolonged exposure to particulate Cr(VI) is cytotoxic and genotoxic to fin whale cells. J Trace Elem Med Biol 2020; 62:126562. [PMID: 32570008 PMCID: PMC7655514 DOI: 10.1016/j.jtemb.2020.126562] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 05/13/2020] [Accepted: 05/20/2020] [Indexed: 01/04/2023]
Abstract
BACKGROUND Hexavalent chromium [Cr(VI)] is a human lung carcinogen and global marine pollutant. High Cr concentrations, resembling the ones observed in occupationally exposed workers, have been observed in fin whales (Balaenoptera physalus) in the Gulf of Maine. This outcome suggests Cr might be disrupting the health of fin whale populations. Indeed, Cr in acute (24 h) exposure does cause toxicity in fin whale cells. However, human cell culture data indicate prolonged exposures (120 h) induce a higher amount of toxicity compared to 24 h exposure due to an inhibition of homologous recombination repair. However, whether prolonged exposure causes similar outcomes in fin whale cells is unknown. OBJECTIVE Due to the importance of assessing prolonged exposure toxicity, this study focuses on characterizing acute and prolonged exposure of Cr(VI) in male and female fin whale cells. METHODS Cytotoxicity was measured by the clonogenic assay, also known as colony forming assay, which measures the ability of cells to proliferate and form colonies after the treatment. DNA double strand breaks were analyzed by neutral comet assay. Clastogenicity was measured using the chromosome aberration assay. Intracellular Cr levels were measured with Graphite Furnace Atomic Absorption Spectrometry (GFAAS) with Syngistix Software. RESULTS In this study, we demonstrate that particulate Cr(VI) induces cytotoxicity and genotoxicity in a treatment-dependent manner after 24 h and 120 h exposures. Cytotoxicity levels were generally low with relative survival above 64 %. DNA double strand break data and chromosome aberration data were elevated after a 24 h exposure, but decreased after a 120 h exposure. While cytotoxicity was similar after 24 h and 120 h exposures, less DNA double strand breaks and chromosomal instability occurred with prolonged exposure. CONCLUSION Particulate Cr(VI) is cytotoxic and genotoxic to fin whale cells after acute and prolonged exposures. The reduction of genotoxicity we have observed after 120 h exposure may be partly explained by lower intracellular Cr levels after 120 h. However, the decrease in intracellular levels is not reflected by a similar decrease in chromosome aberrations suggesting other mechanisms may be at play. Male fin whale cells appear to be more susceptible to the genotoxic effects of particulate Cr(VI) while female cells are less susceptible possibly due to increased cell death of damaged cells, but more work is needed to clarify if this outcome reflects a sex difference or interindividual variability. Overall, the study shows particulate Cr(VI) does induce toxicity at both acute and prolonged exposures in fin whales cells indicating Cr(VI) exposure is a health risk for this species.
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Affiliation(s)
- Idoia Meaza
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston St, Rm 1422, Louisville, KY, United States
| | - Rachel M Speer
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston St, Rm 1422, Louisville, KY, United States
| | - Jennifer H Toyoda
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston St, Rm 1422, Louisville, KY, United States
| | - Haiyan Lu
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston St, Rm 1422, Louisville, KY, United States
| | - Sandra S Wise
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston St, Rm 1422, Louisville, KY, United States
| | - Tayler J Croom-Perez
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston St, Rm 1422, Louisville, KY, United States
| | | | - John Pierce Wise
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston St, Rm 1422, Louisville, KY, United States.
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Vaiopoulou E, Gikas P. Regulations for chromium emissions to the aquatic environment in Europe and elsewhere. CHEMOSPHERE 2020; 254:126876. [PMID: 32957286 DOI: 10.1016/j.chemosphere.2020.126876] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 04/20/2020] [Accepted: 04/21/2020] [Indexed: 05/26/2023]
Abstract
Chromium is a controversial element, since it has been classified as essential trace element, to chemically and biologically inert compound, to potent intoxicator. Concerns have been risen for chromium effects on human and aquatic life because chromium has been accused for genotoxicity and carcinogenesis. Metals and their ions or complexes (and thus chromium substances) are included in the indicative list of main pollutants (Annex VIII of the Water Framework Directive (2000/60/EC)). Biological effects of chromium are strongly depended on chromium speciation. No universal CrIII or CrVI discharge limits to the aquatic environment have been suggested by the EU. International bodies within the EU, such as the Helsinki Commission and the Oslo-Paris Convention, have issued recommendations on chromium discharge levels. National CrVI and CrIII discharge limits vary in each EU Member State with respect to the receiving water body (marine water, lake, river, sewer system). The maximum discharge limit to the aquatic environment in EU is 1 and 5 mg L-1 for CrVI and Crtotal, respectively. The present work summarizes EU legislation, with respect to the discharge limits to the aquatic environment for CrVI and CrIII. EU national limits that are currently effective are presented and compared to the limits in other parts of the world, such as Australia, Asia, USA, Latin America and South Africa. It is wise that future perspective of chromium policy should differentiate between CrIII and CrVI discharge limits to the aquatic environment, as analytical techniques become more sensitive and chromium speciation specific, and environmental awareness rises.
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Affiliation(s)
- Eleni Vaiopoulou
- Concawe, Environmental Science for the European Refining Industry, Boulevard Du Souverain 165, 1160, Brussels, Belgium.
| | - Petros Gikas
- Design of Environmental Processes Laboratory, School of Environmental Engineering, Technical University of Crete, 73100, Chania, Greece.
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Chen QY, Murphy A, Sun H, Costa M. Molecular and epigenetic mechanisms of Cr(VI)-induced carcinogenesis. Toxicol Appl Pharmacol 2019; 377:114636. [PMID: 31228494 DOI: 10.1016/j.taap.2019.114636] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 06/17/2019] [Accepted: 06/18/2019] [Indexed: 12/11/2022]
Abstract
Chromium (Cr) is a naturally occurring metallic element found in the Earth's crust. While trivalent chromium ([Cr(III)] is considered non-carcinogenic, hexavalent chromium [Cr(VI)] has long been established as an IARC class I human carcinogen, known to induce cancers of the lung. Current literature suggests that Cr(VI) is capable of inducing carcinogenesis through both genetic and epigenetic mechanisms. Although much has been learned about the molecular etiology of Cr(VI)-induced lung carcinogenesis, more remains to be explored. In particular, the explicit epigenetic alterations induced by Cr(VI) in lung cancer including histone modifications and miRNAs, remain understudied. Through comprehensive review of available literature found between 1973 and 2019, this article provides a summary of updated understanding of the molecular mechanisms of Cr(VI)-carcinogenesis. In addition, this review identifies potential research gaps in the areas of histone modifications and miRNAs, which may prompt new niches for future research.
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Affiliation(s)
- Qiao Yi Chen
- Department of Environmental Medicine, New York University School of Medicine, 341 East 25 Street, New York, NY 10016, United States of America.
| | - Anthony Murphy
- Department of Environmental Medicine, New York University School of Medicine, 341 East 25 Street, New York, NY 10016, United States of America.
| | - Hong Sun
- Department of Environmental Medicine, New York University School of Medicine, 341 East 25 Street, New York, NY 10016, United States of America.
| | - Max Costa
- Department of Environmental Medicine, New York University School of Medicine, 341 East 25 Street, New York, NY 10016, United States of America.
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Speer RM, Wise SS, Croom-Perez TJ, Aboueissa AM, Martin-Bras M, Barandiaran M, Bermúdez E, Wise JP. A comparison of particulate hexavalent chromium cytotoxicity and genotoxicity in human and leatherback sea turtle lung cells from a one environmental health perspective. Toxicol Appl Pharmacol 2019; 376:70-81. [PMID: 31108106 DOI: 10.1016/j.taap.2019.05.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 05/09/2019] [Accepted: 05/14/2019] [Indexed: 10/26/2022]
Abstract
Evaluating health risks of environmental contaminants can be better achieved by considering toxic impacts across species. Hexavalent chromium [Cr(VI)] is a marine pollutant and global environmental contaminant. While Cr(VI) has been identified as a human lung carcinogen, health effects in marine species are poorly understood. Little is known about how Cr(VI) might impact humans and marine species differently. This study used a One Environmental Health Approach to compare the cytotoxicity and genotoxicity of particulate Cr(VI) in human and leatherback sea turtle (Dermochelys coriacea) lung fibroblasts. Leatherbacks may experience prolonged exposures to environmental contaminants and provide insight to how environmental exposures affect health across species. Since humans and leatherbacks may experience prolonged exposure to Cr(VI), and prolonged Cr(VI) exposure leads to carcinogenesis in humans, in this study we considered both acute and prolonged exposures. We found particulate Cr(VI) induced cytotoxicity in leatherback cells comparable to human cell data supporting current research that shows Cr(VI) impacts health across species. To better understand mechanisms of Cr(VI) toxicity we assessed the genotoxic effects of particulate Cr(VI) in human and leatherback cells. Particulate Cr(VI) induced similar genotoxicity in both cell lines, however, human cells arrested at lower concentrations than leatherback cells. We also measured intracellular Cr ion concentrations and found after prolonged exposure human cells accumulated more Cr than leatherback cells. These data indicate Cr(VI) is a health concern for humans and leatherbacks. The data also suggest humans and leatherbacks respond to chemical exposure differently, possibly leading to the discovery of species-specific protective mechanisms.
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Affiliation(s)
- Rachel M Speer
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston St, Rm 1422, Louisville, KY 40202, United States of America
| | - Sandra S Wise
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston St, Rm 1422, Louisville, KY 40202, United States of America
| | - Tayler J Croom-Perez
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston St, Rm 1422, Louisville, KY 40202, United States of America
| | | | - Mark Martin-Bras
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston St, Rm 1422, Louisville, KY 40202, United States of America; Vieques Conservation and Historical Trust, 138 Calle Flamboyan, Vieques 00765, Puerto Rico
| | - Mike Barandiaran
- U.S. Fish and Wildlife Service, State Rd 997 km 3.2, Vieques 00765, Puerto Rico
| | - Erick Bermúdez
- U.S. Fish and Wildlife Service, State Rd 997 km 3.2, Vieques 00765, Puerto Rico
| | - John Pierce Wise
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville, 500 S Preston St, Rm 1422, Louisville, KY 40202, United States of America.
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Long C, Liu J, Hu G, Feng H, Zhou D, Wang J, Zhai X, Zhao Z, Yu S, Wang T, Jia G. Modulation of homologous recombination repair gene polymorphisms on genetic damage in chromate exposed workers. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2019; 66:126-132. [PMID: 30677706 DOI: 10.1016/j.etap.2019.01.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 12/29/2018] [Accepted: 01/16/2019] [Indexed: 06/09/2023]
Abstract
Hexavalent chromium [Cr(VI)] is one of the most common environmental carcinogens, which is associated with DNA damage, genetic instability and increase the risk of cancer development. However, the mechanisms of genetic damage induced by Cr(VI) remains to be thoroughly illustrated. A molecular epidemiological study was conducted on 120 chromate exposed workers and 97 controls. Results indicated that,the rs12432907 of XRCC3 carrying T allele, the rs144848 of BRCA2 with C allele and the rs1805800 of NBS1 with genotype(TT) of individuals were associated with lower genetic damage, while the rs2295152 of XRCC3 carrying T allele, the rs13312986 (CC and CT genotypes) and the rs2697679 of NBS1 with A allele were associated with higher genetic damage in workers exposed to chromate. The interaction of chromate exposure with rs2295152 of XRCC3 had a significant effect on micronuclei frequency (MNF). The gene polymorphisms in homologous recombination repair pathway could modulate chromate-induced genetic damage.
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Affiliation(s)
- Changmao Long
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Jiaxing Liu
- Department of Medical Record, Third Hospital of Peking University, Beijing, 100191, PR China
| | - Guiping Hu
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Huimin Feng
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Di Zhou
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Jing Wang
- Yima Center for Disease Control and Prevention, Sanmenxia City, Henan Province, 472300, PR China
| | - Xinxia Zhai
- Yima Center for Disease Control and Prevention, Sanmenxia City, Henan Province, 472300, PR China
| | - Zuchang Zhao
- Sanmenxia Municipal Center for Disease Control and Prevention, Sanmenxia, Henan Province, 472000, PR China
| | - Shanfa Yu
- Institute of Occupational Disease Prevention, Zhengzhou City, Henan Province, 450052, PR China
| | - Tiancheng Wang
- Department of Clinical Laboratories, Third Hospital of Peking University, Beijing 100191, PR China
| | - Guang Jia
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, 100191, PR China.
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Krishnaraj J, Baba AB, Viswanathan P, Veeravarmal V, Balasubramanian V, Nagini S. Impact of stainless-steel welding fumes on proteins and non-coding RNAs regulating DNA damage response in the respiratory tract of Sprague-Dawley rats. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2018; 81:1231-1245. [PMID: 30507362 DOI: 10.1080/15287394.2018.1550027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Substantial evidence has established the negative impact of inhalation exposure to welding fumes on respiratory functions. The aim of the present study was to investigate the effect of welding fume inhalation on expression of molecules that function as sensors, transducers and effectors of DNA damage response (DDR) in the respiratory tract of male Sprague-Dawley rats. Animals were exposed to 50 mg/m3 stainless steel welding fumes for 1 h/d for 4, 8, and 12 weeks, respectively. Histological examination demonstrated preneoplastic changes in trachea and bronchi with focal atelectasis and accumulation of chromium (Cr) in the lungs. This was associated with elevated levels of DNA damage markers (8-oxodG, γH2AX), ATM phosphorylation, cell cycle arrest, apoptosis induction, activation of homologous recombination (HR), non-homologous end joining (NHEJ), and Nrf2 signaling, as well as altered expression of noncoding RNAs (ncRNAs). However, after 12 weeks of exposure, DDR was compromised as reflected by resumption of the cell cycle, repair inhibition, and failure of apoptosis. Data demonstrate that exposure to welding fumes influences two crucial layers of DDR regulation, phosphorylation of key proteins in NHEJ and HR, as well as the ncRNAs that epigenetically modulate DDR. Evidence indicates that marked DNA damage coupled with non-productive DNA repair and apoptosis avoidance may be involved in neoplastic transformation.
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Affiliation(s)
- Jayaraman Krishnaraj
- a Department of Biochemistry and Biotechnology, Faculty of Science , Annamalai University , Annamalainagar , TN , India
| | - Abdul Basit Baba
- a Department of Biochemistry and Biotechnology, Faculty of Science , Annamalai University , Annamalainagar , TN , India
| | - Periasamy Viswanathan
- b Division of Pathology, Rajah Muthiah Medical College & Hospital , Annamalai University , Annamalinagar , TN , India
| | - Veeran Veeravarmal
- c Division of Oral Pathology, Rajah Muthiah Dental College & Hospital , Annamalai University , Annamalinagar , TN , India
| | - Viswalingam Balasubramanian
- d Department of Manufacturing Engineering, Faculty of Engineering and Technology , Annamalai University , Annamalainagar , TN , India
| | - Siddavaram Nagini
- a Department of Biochemistry and Biotechnology, Faculty of Science , Annamalai University , Annamalainagar , TN , India
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Tdp1 processes chromate-induced single-strand DNA breaks that collapse replication forks. PLoS Genet 2018; 14:e1007595. [PMID: 30148840 PMCID: PMC6128646 DOI: 10.1371/journal.pgen.1007595] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 09/07/2018] [Accepted: 07/26/2018] [Indexed: 01/20/2023] Open
Abstract
Hexavalent chromium [Cr(VI)] damages DNA and causes cancer, but it is unclear which DNA damage responses (DDRs) most critically protect cells from chromate toxicity. Here, genome-wide quantitative functional profiling, DDR measurements and genetic interaction assays in Schizosaccharomyces pombe reveal a chromate toxicogenomic profile that closely resembles the cancer chemotherapeutic drug camptothecin (CPT), which traps Topoisomerase 1 (Top1)-DNA covalent complex (Top1cc) at the 3’ end of single-stand breaks (SSBs), resulting in replication fork collapse. ATR/Rad3-dependent checkpoints that detect stalled and collapsed replication forks are crucial in Cr(VI)-treated cells, as is Mus81-dependent sister chromatid recombination (SCR) that repairs single-ended double-strand breaks (seDSBs) at broken replication forks. Surprisingly, chromate resistance does not require base excision repair (BER) or interstrand crosslink (ICL) repair, nor does co-elimination of XPA-dependent nucleotide excision repair (NER) and Rad18-mediated post-replication repair (PRR) confer chromate sensitivity in fission yeast. However, co-elimination of Tdp1 tyrosyl-DNA phosphodiesterase and Rad16-Swi10 (XPF-ERCC1) NER endonuclease synergistically enhances chromate toxicity in top1Δ cells. Pnk1 polynucleotide kinase phosphatase (PNKP), which restores 3’-hydroxyl ends to SSBs processed by Tdp1, is also critical for chromate resistance. Loss of Tdp1 ameliorates pnk1Δ chromate sensitivity while enhancing the requirement for Mus81. Thus, Tdp1 and PNKP, which prevent neurodegeneration in humans, repair an important class of Cr-induced SSBs that collapse replication forks. Hexavalent chromium is a carcinogen that is found at toxic waste sites and in some groundwater supplies. Cellular metabolism converts chromium into DNA-damaging chromate, but it is unclear which types of chromate-DNA lesions are most dangerous, and which cellular mechanisms most critically prevent chromium toxicity. This study uses whole-genome profiling to identify DNA repair pathways that are crucial for chromate resistance in fission yeast. The resulting ‘toxicogenomic’ profile of chromate closely matches camptothecin, a natural product representing a class of chemotherapeutic drugs that cause replication fork collapse by poisoning Topoisomerase 1 (Top1), which relaxes supercoiled DNA by creating and resealing single-strand breaks (SSBs). Genetic interaction analyses uncover important roles for Tdp1 tyrosyl-DNA phosphodiesterase and Pnk1 polynucleotide 5’-kinase 3’-phosphatase (PNKP), which repair camptothecin-induced SSBs and prevent neurological disease in humans. However, chromium toxicity does not involve Top1. As Tdp1 and Pnk1 repair SSBs with 3’-blocked termini, these data suggest that Top1-independent 3’-blocked SSBs contribute to the carcinogenic and mutagenic properties of chromium.
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23
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Li J, Svilar D, McClellan S, Kim JH, Ahn EYE, Vens C, Wilson DM, Sobol RW. DNA Repair Molecular Beacon assay: a platform for real-time functional analysis of cellular DNA repair capacity. Oncotarget 2018; 9:31719-31743. [PMID: 30167090 PMCID: PMC6114979 DOI: 10.18632/oncotarget.25859] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 07/12/2018] [Indexed: 12/15/2022] Open
Abstract
Numerous studies have shown that select DNA repair enzyme activities impact response and/or toxicity of genotoxins, suggesting a requirement for enzyme functional analyses to bolster precision medicine or prevention. To address this need, we developed a DNA Repair Molecular Beacon (DRMB) platform that rapidly measures DNA repair enzyme activity in real-time. The DRMB assay is applicable for discovery of DNA repair enzyme inhibitors, for the quantification of enzyme rates and is sufficiently sensitive to differentiate cellular enzymatic activity that stems from variation in expression or effects of amino acid substitutions. We show activity measures of several different base excision repair (BER) enzymes, including proteins with tumor-identified point mutations, revealing lesion-, lesion-context- and cell-type-specific repair dependence; suggesting application for DNA repair capacity analysis of tumors. DRMB measurements using lysates from isogenic control and APE1-deficient human cells suggests the major mechanism of base lesion removal by most DNA glycosylases may be mono-functional base hydrolysis. In addition, development of a microbead-conjugated DRMB assay amenable to flow cytometric analysis further advances its application. Our studies establish an analytical platform capable of evaluating the enzyme activity of select DNA repair proteins in an effort to design and guide inhibitor development and precision cancer therapy options.
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Affiliation(s)
- Jianfeng Li
- University of South Alabama Mitchell Cancer Institute, Mobile, AL, USA
| | - David Svilar
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.,University of Pittsburgh Cancer Institute, Hillman Cancer Center, Pittsburgh, PA, USA
| | - Steven McClellan
- University of South Alabama Mitchell Cancer Institute, Mobile, AL, USA
| | - Jung-Hyun Kim
- University of South Alabama Mitchell Cancer Institute, Mobile, AL, USA
| | | | - Conchita Vens
- The Netherlands Cancer Institute, Division of Cell Biology, Amsterdam, The Netherlands
| | - David M Wilson
- Laboratory of Molecular Gerontology, National Institute on Aging, IRP, NIH Baltimore, MD, USA
| | - Robert W Sobol
- University of South Alabama Mitchell Cancer Institute, Mobile, AL, USA.,Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.,University of Pittsburgh Cancer Institute, Hillman Cancer Center, Pittsburgh, PA, USA
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24
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Wise SS, Aboueissa AEM, Martino J, Wise JP. Hexavalent Chromium-Induced Chromosome Instability Drives Permanent and Heritable Numerical and Structural Changes and a DNA Repair-Deficient Phenotype. Cancer Res 2018; 78:4203-4214. [PMID: 29880483 PMCID: PMC6072558 DOI: 10.1158/0008-5472.can-18-0531] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 05/03/2018] [Accepted: 06/04/2018] [Indexed: 11/16/2022]
Abstract
A key hypothesis for how hexavalent chromium [Cr(VI)] causes cancer is that it drives chromosome instability (CIN), which leads to neoplastic transformation. Studies show chronic Cr(VI) can affect DNA repair and induce centrosome amplification, which can lead to structural and numerical CIN. However, no studies have considered whether these outcomes are transient or permanent. In this study, we exposed human lung cells to particulate Cr(VI) for three sequential 24-hour periods, each separated by about a month. After each treatment, cells were seeded at colony-forming density, cloned, expanded, and retreated, creating three generations of clonal cell lines. Each generation of clones was tested for chromium sensitivity, chromosome complement, DNA repair capacity, centrosome amplification, and the ability to grow in soft agar. After the first treatment, Cr(VI)-treated clones exhibited a normal chromosome complement, but some clones showed a repair-deficient phenotype and amplified centrosomes. After the second exposure, more than half of the treated clones acquired an abnormal karyotype including numerical and structural alterations, with many exhibiting deficient DNA double-strand break repair and amplified centrosomes. The third treatment produced new abnormal clones, with previously abnormal clones acquiring additional abnormalities and most clones exhibiting repair deficiency. CIN, repair deficiency, and amplified centrosomes were all permanent and heritable phenotypes of repeated Cr(VI) exposure. These outcomes support the hypothesis that CIN is a key mechanism of Cr(VI)-induced carcinogenesis.Significance: Chromium, a major public health concern and human lung carcinogen, causes fundamental changes in chromosomes and DNA repair in human lung cells. Cancer Res; 78(15); 4203-14. ©2018 AACR.
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Affiliation(s)
- Sandra S Wise
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, Kentucky
| | | | - Julieta Martino
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, Kentucky
| | - John Pierce Wise
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, Kentucky.
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25
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Hu G, Li P, Cui X, Li Y, Zhang J, Zhai X, Yu S, Tang S, Zhao Z, Wang J, Jia G. Cr(VI)-induced methylation and down-regulation of DNA repair genes and its association with markers of genetic damage in workers and 16HBE cells. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 238:833-843. [PMID: 29627753 DOI: 10.1016/j.envpol.2018.03.046] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Revised: 12/15/2017] [Accepted: 03/14/2018] [Indexed: 06/08/2023]
Abstract
To examine the mechanism of hexavalent chromium [Cr(VI)]-induced carcinogenesis, a cross-sectional study in workers with or without exposure to Cr(VI) as well as in vitro administration of Cr(VI) in 16HBE cells was conducted. We explored the associations between Cr(VI) exposure, methylation modification of DNA repair genes and their expression levels, and genetic damage. Results showed that hypermethylation of CpG sites were observed in both occupationally exposed workers and 16HBE cells administrated Cr(VI). DNA damage markers including 8-hydroxydeoxyguanosine (8-OHdG) and micronucleus frequency in Cr(VI)-exposed workers were significantly higher than the control group. Among workers, blood Cr concentration was positively correlaed with the methylation level of CpG sites in DNA repair genes including CpG6,7, CpG8, CpG9,10,11 of MGMT, CpG11 of HOGG1; CpG15,16,17, CpG19 of RAD51, and genetic damage markers including 8-OHdG and micronucleus frequency. Significant negative association between methylation levels of CpG sites in DNA repair genes and corresponding mRNA was also observed in 16HBE cells. This indicated that Cr(VI) exposure can down-regulate DNA repair gene expression by hypermethylation, which leads to enhanced genetic damage. The methylation level of these CpG sites of DNA repair genes can be potential epigenetic markers for Cr(VI)-induced DNA damage.
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Affiliation(s)
- Guiping Hu
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, 100191, China
| | - Ping Li
- Laboratory of Nutrition, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Xiaoxing Cui
- Nicholas School of the Environment, Duke University, Box 90328, Durham, NC, USA
| | - Yang Li
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, 100191, China; Beijing Key Laboratory of Occupational Safety and Health, Beijing, 100054, China
| | - Ji Zhang
- Jinan Center for Disease Control and Prevention, Jinan, Shandong Province, 250021, China
| | - Xinxiao Zhai
- Yima Center for Disease Control and Prevention, Sanmenxia City, Henan Province, 472300, China
| | - Shanfa Yu
- Institute of Occupational Disease Prevention, Zhengzhou City, Henan Province, 450052, China
| | - Shichuan Tang
- Beijing Key Laboratory of Occupational Safety and Health, Beijing, 100054, China
| | - Zuchang Zhao
- Sanmenxia Municipal Center for Disease Control and Prevention, Sanmenxia, Henan Province, 472000, China
| | - Jing Wang
- Yima Center for Disease Control and Prevention, Sanmenxia City, Henan Province, 472300, China
| | - Guang Jia
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, 100191, China.
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VonHandorf A, Sánchez-Martín FJ, Biesiada J, Zhang H, Zhang X, Medvedovic M, Puga A. Chromium disrupts chromatin organization and CTCF access to its cognate sites in promoters of differentially expressed genes. Epigenetics 2018; 13:363-375. [PMID: 29561703 PMCID: PMC6140807 DOI: 10.1080/15592294.2018.1454243] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 03/12/2018] [Accepted: 03/13/2018] [Indexed: 01/22/2023] Open
Abstract
Hexavalent chromium compounds are well-established respiratory carcinogens used in industrial processes. While inhalation exposure constitutes an occupational risk affecting mostly chromium workers, environmental exposure from drinking water is a widespread gastrointestinal cancer risk, affecting millions of people throughout the world. Cr(VI) is genotoxic, forming protein-Cr-DNA adducts and silencing tumor suppressor genes, but its mechanism of action at the molecular level is poorly understood. Our prior work using FAIRE showed that Cr(VI) disrupted the binding of transcription factors CTCF and AP-1 to their cognate chromatin sites. Here, we used two complementary approaches to test the hypothesis that chromium perturbs chromatin organization and dynamics. DANPOS2 analyses of MNase-seq data identified several chromatin alterations induced by Cr(VI) affecting nucleosome architecture, including occupancy changes at specific genome locations; position shifts of 10 nucleotides or more; and changes in position amplitude or fuzziness. ATAC-seq analysis revealed that Cr(VI) disrupted the accessibility of chromatin regions enriched for CTCF and AP-1 binding motifs, with a significant co-occurrence of binding sites for both factors in the same region. Cr(VI)-enriched CTCF sites were confirmed by ChIP-seq and found to correlate with evolutionarily conserved sites occupied by CTCF in vivo, as determined by comparison with ENCODE-validated CTCF datasets from mouse liver. In addition, more than 30% of the Cr(VI)-enriched CTCF sites were located in promoters of genes differentially expressed from chromium treatment. Our results support the conclusion that Cr(VI) exposure promotes broad changes in chromatin accessibility and suggest that the subsequent effects on transcription regulation may result from disruption of CTCF binding and nucleosome spacing, implicating transcription regulatory mechanisms as primary Cr(VI) targets.
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Affiliation(s)
- Andrew VonHandorf
- Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United State
| | - Francisco Javier Sánchez-Martín
- Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United State
| | - Jacek Biesiada
- Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United State
| | - Hongxia Zhang
- Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United State
| | - Xiang Zhang
- Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United State
| | - Mario Medvedovic
- Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United State
| | - Alvaro Puga
- Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United State
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Browning CL, Wise JP. Prolonged exposure to particulate chromate inhibits RAD51 nuclear import mediator proteins. Toxicol Appl Pharmacol 2017; 331:101-107. [PMID: 28554658 PMCID: PMC5568470 DOI: 10.1016/j.taap.2017.05.030] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 05/19/2017] [Accepted: 05/24/2017] [Indexed: 12/21/2022]
Abstract
Particulate hexavalent chromium (Cr(VI)) is a human lung carcinogen and a human health concern. The induction of structural chromosome instability is considered to be a driving mechanism of Cr(VI)-induced carcinogenesis. Homologous recombination repair protects against Cr(VI)-induced chromosome damage, due to its highly accurate repair of Cr(VI)-induced DNA double strand breaks. However, recent studies demonstrate Cr(VI) inhibits homologous recombination repair through the misregulation of RAD51. RAD51 is an essential protein in HR repair that facilitates the search for a homologous sequence. Recent studies show prolonged Cr(VI) exposure prevents proper RAD51 subcellular localization, causing it to accumulate in the cytoplasm. Since nuclear import of RAD51 is crucial to its function, this study investigated the effect of Cr(VI) on the RAD51 nuclear import mediators, RAD51C and BRCA2. We show acute (24h) Cr(VI) exposure induces the proper localization of RAD51C and BRCA2. In contrast, prolonged (120h) exposure increased the cytoplasmic localization of both proteins, although RAD51C localization was more severely impaired. These results correlate temporally with the previously reported Cr(VI)-induced RAD51 cytoplasmic accumulation. In addition, we found Cr(VI) does not inhibit interaction between RAD51 and its nuclear import mediators. Altogether, our results suggest prolonged Cr(VI) exposure inhibits the nuclear import of RAD51C, and to a lesser extent, BRCA2, which results in the cytoplasmic accumulation of RAD51. Cr(VI)-induced inhibition of nuclear import may play a key role in its carcinogenic mechanism since the nuclear import of many tumor suppressor proteins and DNA repair proteins is crucial to their function.
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Affiliation(s)
- Cynthia L Browning
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40292, United States; Graduate School of Biomedical Science and Engineering, University of Maine, Orono, ME 04469, United States.
| | - John Pierce Wise
- Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40292, United States; Graduate School of Biomedical Science and Engineering, University of Maine, Orono, ME 04469, United States.
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28
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Prolonged particulate chromate exposure does not inhibit homologous recombination repair in North Atlantic right whale (Eubalaena glacialis) lung cells. Toxicol Appl Pharmacol 2017; 331:18-23. [PMID: 28411036 DOI: 10.1016/j.taap.2017.04.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 04/06/2017] [Accepted: 04/07/2017] [Indexed: 01/28/2023]
Abstract
Chromosome instability is a common feature of cancers that forms due to the misrepair of DNA double strand breaks. Homologous recombination (HR) repair is a high fidelity DNA repair pathway that utilizes a homologous DNA sequence to accurately repair such damage and protect the genome. Prolonged exposure (>72h) to the human lung carcinogen, particulate hexavalent chromium (Cr(VI)), inhibits HR repair, resulting in increased chromosome instability in human cells. Comparative studies have shown acute Cr(VI) exposure induces less chromosome damage in whale cells than human cells, suggesting investigating the effect of this carcinogen in other species may inform efforts to prevent Cr(VI)-induced chromosome instability. Thus, the goal of this study was to determine the effect of prolonged Cr(VI) exposure on HR repair and clastogenesis in North Atlantic right whale (Eubalaena glacialis) lung cells. We show particulate Cr(VI) induces HR repair activity after both acute (24h) and prolonged (120h) exposure in North Atlantic right whale cells. Although the RAD51 response was lower following prolonged Cr(VI) exposure compared to acute exposure, the response was sufficient for HR repair to occur. In accordance with active HR repair, no increase in Cr(VI)-induced clastogenesis was observed with increased exposure time. These results suggest prolonged Cr(VI) exposure affects HR repair and genomic stability differently in whale and human lung cells. Future investigation of the differences in how human and whale cells respond to chemical carcinogens may provide valuable insight into mechanisms of preventing chemical carcinogenesis.
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Browning CL, Qin Q, Kelly DF, Prakash R, Vanoli F, Jasin M, Wise JP. Prolonged Particulate Hexavalent Chromium Exposure Suppresses Homologous Recombination Repair in Human Lung Cells. Toxicol Sci 2016; 153:70-8. [PMID: 27449664 DOI: 10.1093/toxsci/kfw103] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Genomic instability is one of the primary models of carcinogenesis and a feature of almost all cancers. Homologous recombination (HR) repair protects against genomic instability by maintaining high genomic fidelity during the repair of DNA double strand breaks. The defining step of HR repair is the formation of the Rad51 nucleofilament, which facilitates the search for a homologous sequence and invasion of the template DNA strand. Particulate hexavalent chromium (Cr(VI)), a human lung carcinogen, induces DNA double strand breaks and chromosome instability. Since the loss of HR repair increases Cr(VI)-induced chromosome instability, we investigated the effect of extended Cr(VI) exposure on HR repair. We show acute (24 h) Cr(VI) exposure induces a normal HR repair response. In contrast, prolonged (120 h) exposure to particulate Cr(VI) inhibited HR repair and Rad51 nucleofilament formation. Prolonged Cr(VI) exposure had a profound effect on Rad51, evidenced by reduced protein levels and Rad51 mislocalization to the cytoplasm. The response of proteins involved in Rad51 nuclear import and nucleofilament formation displayed varying responses to prolonged Cr(VI) exposure. BRCA2 formed nuclear foci after prolonged Cr(VI) exposure, while Rad51C foci formation was suppressed. These results suggest that particulate Cr(VI), a major chemical carcinogen, inhibits HR repair by targeting Rad51, causing DNA double strand breaks to be repaired by a low fidelity, Rad51-independent repair pathway. These results further enhance our understanding of the underlying mechanism of Cr(VI)-induced chromosome instability and thus, carcinogenesis.
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Affiliation(s)
- Cynthia L Browning
- *Wise Laboratory of Environmental and Genetic Toxicology, Portland, Maine 04104 Graduate School of Biomedical Science and Engineering, University of Maine, Orono, Maine 04469
| | - Qin Qin
- *Wise Laboratory of Environmental and Genetic Toxicology, Portland, Maine 04104 Virginia Tech Carilion Research Institute, Roanoke, Virginia 24016
| | - Deborah F Kelly
- Virginia Tech Carilion Research Institute, Roanoke, Virginia 24016
| | - Rohit Prakash
- Memorial Sloan Kettering Cancer Center, New York 10065, New York
| | - Fabio Vanoli
- Memorial Sloan Kettering Cancer Center, New York 10065, New York
| | - Maria Jasin
- Memorial Sloan Kettering Cancer Center, New York 10065, New York
| | - John Pierce Wise
- *Wise Laboratory of Environmental and Genetic Toxicology, Portland, Maine 04104 Graduate School of Biomedical Science and Engineering, University of Maine, Orono, Maine 04469
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30
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Li Y, Hu G, Li P, Tang S, Zhang J, Jia G. miR-3940-5p enhances homologous recombination after DSB in Cr(VI) exposed 16HBE cell. Toxicology 2016; 344-346:1-6. [DOI: 10.1016/j.tox.2016.02.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 02/04/2016] [Accepted: 02/05/2016] [Indexed: 12/11/2022]
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31
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Martino J, Holmes AL, Xie H, Wise SS, Wise JP. Chronic Exposure to Particulate Chromate Induces Premature Centrosome Separation and Centriole Disengagement in Human Lung Cells. Toxicol Sci 2015; 147:490-9. [PMID: 26293554 PMCID: PMC4635651 DOI: 10.1093/toxsci/kfv146] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Particulate hexavalent chromium (Cr(VI)) is a well-established human lung carcinogen. Lung tumors are characterized by structural and numerical chromosome instability. Centrosome amplification is a phenotype commonly found in solid tumors, including lung tumors, which strongly correlates with chromosome instability. Human lung cells exposed to Cr(VI) exhibit centrosome amplification but the underlying phenotypes and mechanisms remain unknown. In this study, we further characterize the phenotypes of Cr(VI)-induced centrosome abnormalities. We show that Cr(VI)-induced centrosome amplification correlates with numerical chromosome instability. We also show chronic exposure to particulate Cr(VI) induces centrosomes with supernumerary centrioles and acentriolar centrosomes in human lung cells. Moreover, chronic exposure to particulate Cr(VI) affects the timing of important centriolar events. Specifically, chronic exposure to particulate Cr(VI) causes premature centriole disengagement in S and G2 phase cells. It also induces premature centrosome separation in interphase. Altogether, our data suggest that chronic exposure to particulate Cr(VI) targets the protein linkers that hold centrioles together. These centriolar linkers are important for key events of the centrosome cycle and their premature disruption might underlie Cr(VI)-induced centrosome amplification.
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Affiliation(s)
- Julieta Martino
- *Wise Laboratory of Environmental and Genetic Toxicology and Department of Applied Medical Sciences, Maine Center for Toxicology and Environmental Health, University of Southern Maine, Portland, Maine 04104; and
| | - Amie L Holmes
- *Wise Laboratory of Environmental and Genetic Toxicology and Department of Applied Medical Sciences, Maine Center for Toxicology and Environmental Health, University of Southern Maine, Portland, Maine 04104; and
| | - Hong Xie
- *Wise Laboratory of Environmental and Genetic Toxicology and Department of Applied Medical Sciences, Maine Center for Toxicology and Environmental Health, University of Southern Maine, Portland, Maine 04104; and
| | - Sandra S Wise
- *Wise Laboratory of Environmental and Genetic Toxicology and Department of Applied Medical Sciences, Maine Center for Toxicology and Environmental Health, University of Southern Maine, Portland, Maine 04104; and Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40068
| | - John Pierce Wise
- *Wise Laboratory of Environmental and Genetic Toxicology and Department of Applied Medical Sciences, Maine Center for Toxicology and Environmental Health, University of Southern Maine, Portland, Maine 04104; and Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40068
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