1
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Venu V, Roth C, Adikari SH, Small EM, Starkenburg SR, Sanbonmatsu KY, Steadman CR. Multi-omics analysis reveals the dynamic interplay between Vero host chromatin structure and function during vaccinia virus infection. Commun Biol 2024; 7:721. [PMID: 38862613 PMCID: PMC11166932 DOI: 10.1038/s42003-024-06389-x] [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: 01/03/2024] [Accepted: 05/27/2024] [Indexed: 06/13/2024] Open
Abstract
The genome folds into complex configurations and structures thought to profoundly impact its function. The intricacies of this dynamic structure-function relationship are not well understood particularly in the context of viral infection. To unravel this interplay, here we provide a comprehensive investigation of simultaneous host chromatin structural (via Hi-C and ATAC-seq) and functional changes (via RNA-seq) in response to vaccinia virus infection. Over time, infection significantly impacts global and local chromatin structure by increasing long-range intra-chromosomal interactions and B compartmentalization and by decreasing chromatin accessibility and inter-chromosomal interactions. Local accessibility changes are independent of broad-scale chromatin compartment exchange (~12% of the genome), underscoring potential independent mechanisms for global and local chromatin reorganization. While infection structurally condenses the host genome, there is nearly equal bidirectional differential gene expression. Despite global weakening of intra-TAD interactions, functional changes including downregulated immunity genes are associated with alterations in local accessibility and loop domain restructuring. Therefore, chromatin accessibility and local structure profiling provide impactful predictions for host responses and may improve development of efficacious anti-viral counter measures including the optimization of vaccine design.
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Affiliation(s)
- Vrinda Venu
- Climate, Ecology & Environment Group, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Cullen Roth
- Genomics & Bioanalytics Group, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Samantha H Adikari
- Biochemistry & Biotechnology Group, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Eric M Small
- Climate, Ecology & Environment Group, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Shawn R Starkenburg
- Genomics & Bioanalytics Group, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Karissa Y Sanbonmatsu
- Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, NM, USA
- New Mexico Consortium, Los Alamos, NM, USA
| | - Christina R Steadman
- Climate, Ecology & Environment Group, Los Alamos National Laboratory, Los Alamos, NM, USA.
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2
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Rea M, Kimmerer G, Mittendorf S, Xiong X, Green M, Chandler D, Saintilnord W, Blackburn J, Gao T, Fondufe-Mittendorf YN. A dynamic model of inorganic arsenic-induced carcinogenesis reveals an epigenetic mechanism for epithelial-mesenchymal plasticity. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 347:123586. [PMID: 38467368 PMCID: PMC11005477 DOI: 10.1016/j.envpol.2024.123586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 02/12/2024] [Accepted: 02/14/2024] [Indexed: 03/13/2024]
Abstract
Inorganic arsenic (iAs) causes cancer by initiating dynamic transitions between epithelial and mesenchymal cell phenotypes. These transitions transform normal cells into cancerous cells, and cancerous cells into metastatic cells. Most in vitro models assume that transitions between states are binary and complete, and do not consider the possibility that intermediate, stable cellular states might exist. In this paper, we describe a new, two-hit in vitro model of iAs-induced carcinogenesis that extends to 28 weeks of iAs exposure. Through week 17, the model faithfully recapitulates known and expected phenotypic, genetic, and epigenetic characteristics of iAs-induced carcinogenesis. By 28 weeks, however, exposed cells exhibit stable, intermediate phenotypes and epigenetic properties, and key transcription factor promoters (SNAI1, ZEB1) enter an epigenetically poised or bivalent state. These data suggest that key epigenetic transitions and cellular states exist during iAs-induced epithelial-to-mesenchymal transition (EMT), and that it is important for our in vitro models to encapsulate all aspects of EMT and the mesenchymal-to-epithelial transition (MET). In so doing, and by understanding the epigenetic systems controlling these transitions, we might find new, unexpected opportunities for developing targeted, cell state-specific therapeutics.
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Affiliation(s)
- Matthew Rea
- Department of Epigenetics, Van Andel Institute, Grand Rapids, MI, 49502, USA
| | - Greg Kimmerer
- Department of Biology, University of Kentucky, Lexington, KY, 40506, USA
| | - Shania Mittendorf
- Department of Biology, University of Kentucky, Lexington, KY, 40506, USA
| | - Xiaopeng Xiong
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, 40536, USA; Markey Cancer Center, University of Kentucky, Lexington, KY, 40536, USA
| | - Meghan Green
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, 40536, USA; Markey Cancer Center, University of Kentucky, Lexington, KY, 40536, USA
| | - Darrell Chandler
- Department of Epigenetics, Van Andel Institute, Grand Rapids, MI, 49502, USA
| | - Wesley Saintilnord
- Department of Epigenetics, Van Andel Institute, Grand Rapids, MI, 49502, USA; Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, 40536, USA
| | - Jessica Blackburn
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, 40536, USA; Markey Cancer Center, University of Kentucky, Lexington, KY, 40536, USA
| | - Tianyan Gao
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, 40536, USA; Markey Cancer Center, University of Kentucky, Lexington, KY, 40536, USA
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3
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O’Connor C, Keele GR, Martin W, Stodola T, Gatti D, Hoffman BR, Korstanje R, Churchill GA, Reinholdt LG. Unraveling the genetics of arsenic toxicity with cellular morphology QTL. PLoS Genet 2024; 20:e1011248. [PMID: 38662777 PMCID: PMC11075906 DOI: 10.1371/journal.pgen.1011248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 05/07/2024] [Accepted: 04/03/2024] [Indexed: 05/08/2024] Open
Abstract
The health risks that arise from environmental exposures vary widely within and across human populations, and these differences are largely determined by genetic variation and gene-by-environment (gene-environment) interactions. However, risk assessment in laboratory mice typically involves isogenic strains and therefore, does not account for these known genetic effects. In this context, genetically heterogenous cell lines from laboratory mice are promising tools for population-based screening because they provide a way to introduce genetic variation in risk assessment without increasing animal use. Cell lines from genetic reference populations of laboratory mice offer genetic diversity, power for genetic mapping, and potentially, predictive value for in vivo experimentation in genetically matched individuals. To explore this further, we derived a panel of fibroblast lines from a genetic reference population of laboratory mice (the Diversity Outbred, DO). We then used high-content imaging to capture hundreds of cell morphology traits in cells exposed to the oxidative stress-inducing arsenic metabolite monomethylarsonous acid (MMAIII). We employed dose-response modeling to capture latent parameters of response and we then used these parameters to identify several hundred cell morphology quantitative trait loci (cmQTL). Response cmQTL encompass genes with established associations with cellular responses to arsenic exposure, including Abcc4 and Txnrd1, as well as novel gene candidates like Xrcc2. Moreover, baseline trait cmQTL highlight the influence of natural variation on fundamental aspects of nuclear morphology. We show that the natural variants influencing response include both coding and non-coding variation, and that cmQTL haplotypes can be used to predict response in orthogonal cell lines. Our study sheds light on the major molecular initiating events of oxidative stress that are under genetic regulation, including the NRF2-mediated antioxidant response, cellular detoxification pathways, DNA damage repair response, and cell death trajectories.
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Affiliation(s)
- Callan O’Connor
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
- Graduate School of Biomedical Sciences, Tufts University, Boston, Massachusetts, United States of America
| | - Gregory R. Keele
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
- RTI International, Research Triangle Park, Durham, North Carolina, United States of America
| | - Whitney Martin
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | - Timothy Stodola
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | - Daniel Gatti
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | - Brian R. Hoffman
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | - Ron Korstanje
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
- Graduate School of Biomedical Sciences, Tufts University, Boston, Massachusetts, United States of America
| | - Gary A. Churchill
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
- Graduate School of Biomedical Sciences, Tufts University, Boston, Massachusetts, United States of America
| | - Laura G. Reinholdt
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
- Graduate School of Biomedical Sciences, Tufts University, Boston, Massachusetts, United States of America
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4
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O'Connor C, Keele GR, Martin W, Stodola T, Gatti D, Hoffman BR, Korstanje R, Churchill GA, Reinholdt LG. Cell morphology QTL reveal gene by environment interactions in a genetically diverse cell population. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.18.567597. [PMID: 38014303 PMCID: PMC10680806 DOI: 10.1101/2023.11.18.567597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Genetically heterogenous cell lines from laboratory mice are promising tools for population-based screening as they offer power for genetic mapping, and potentially, predictive value for in vivo experimentation in genetically matched individuals. To explore this further, we derived a panel of fibroblast lines from a genetic reference population of laboratory mice (the Diversity Outbred, DO). We then used high-content imaging to capture hundreds of cell morphology traits in cells exposed to the oxidative stress-inducing arsenic metabolite monomethylarsonous acid (MMAIII). We employed dose-response modeling to capture latent parameters of response and we then used these parameters to identify several hundred cell morphology quantitative trait loci (cmQTL). Response cmQTL encompass genes with established associations with cellular responses to arsenic exposure, including Abcc4 and Txnrd1, as well as novel gene candidates like Xrcc2. Moreover, baseline trait cmQTL highlight the influence of natural variation on fundamental aspects of nuclear morphology. We show that the natural variants influencing response include both coding and non-coding variation, and that cmQTL haplotypes can be used to predict response in orthogonal cell lines. Our study sheds light on the major molecular initiating events of oxidative stress that are under genetic regulation, including the NRF2-mediated antioxidant response, cellular detoxification pathways, DNA damage repair response, and cell death trajectories.
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Affiliation(s)
- Callan O'Connor
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
- Graduate School of Biomedical Sciences, Tufts University, Boston, MA 02111, USA
| | - Gregory R Keele
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
- RTI International, RTP, NC 27709, USA
| | | | | | - Daniel Gatti
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
| | | | | | | | - Laura G Reinholdt
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
- Graduate School of Biomedical Sciences, Tufts University, Boston, MA 02111, USA
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5
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Stößer S, Lumpp T, Fischer F, Gunesch S, Schumacher P, Hartwig A. Effect of Long-Term Low-Dose Arsenic Exposure on DNA Methylation and Gene Expression in Human Liver Cells. Int J Mol Sci 2023; 24:15238. [PMID: 37894918 PMCID: PMC10607230 DOI: 10.3390/ijms242015238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 09/30/2023] [Accepted: 10/13/2023] [Indexed: 10/29/2023] Open
Abstract
Millions of people around the world are exposed to elevated levels of arsenic through food or drinking water. Epidemiological studies have linked chronic arsenic exposure to an increased risk of several cancers, cardiovascular disease, central nervous system neuropathies, and genotoxic as well as immunotoxic effects. In addition to the induction of oxidative stress and inhibition of DNA repair processes, epigenetic effects, including altered DNA methylation patterns resulting in aberrant gene expression, may contribute to carcinogenicity. However, the underlying mechanisms by which chronic micromolar concentrations of arsenite affect the methylation status of DNA are not fully understood. In this study, human HepG2 hepatocarcinoma cells were treated with 0.5-10 μM sodium arsenite for 24 h, 10, or 20 days. During these periods, the effects on global DNA methylation, cell cycle phase distribution, and gene expression were investigated. While no impact on DNA methylation was seen after short-term exposure, global hypomethylation was observed at both long-term exposure periods, with concomitant induction of the DNA methyltransferase genes DNMT1 and DNMT3B, while DNMT3A was slightly down-regulated. Pronounced time- and concentration-dependent effects were also seen in the case of genes involved in DNA damage response and repair, inflammation, oxidative stress response, and metal homeostasis. These results suggest that chronic low-dose arsenite exposure can lead to global hypomethylation. As an underlying mechanism, the consistent down-regulation of DNA methyltransferase genes could be excluded; alternatively, interactions at the protein level could play an important role.
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Affiliation(s)
| | | | | | | | | | - Andrea Hartwig
- Department of Food Chemistry and Toxicology, Institute of Applied Biosciences (IAB), Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany
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6
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Illingworth EJ, Maertens A, Sillé FCM. Transcriptomic Effects of Low-Dose Inorganic Arsenic Exposure on Murine Bone Marrow-Derived Macrophages. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.26.550543. [PMID: 37546857 PMCID: PMC10402011 DOI: 10.1101/2023.07.26.550543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Both tissue-resident macrophages and monocytes recruited from the bone marrow that transform into tissue-resident cells play critical roles in mediating homeostasis as well as in the pathology of inflammatory diseases. Inorganic arsenic (iAs) is the most common drinking water contaminant worldwide and represents a major public health concern. Several diseases that macrophages have implicated involvement in are caused by iAs exposure, including cardiovascular disease, cancer, and increased risk of infectious disease. Therefore, understanding the effects of iAs exposure on macrophages can help us better grasp the full range of arsenic immunotoxicity and better design therapeutic targets for iAs-induced diseases particularly in exposed populations. In this study, we analyzed the transcriptome of low dose iAs-exposed male and female murine bone marrow-derived macrophages (BMDMs) with either M0, M1, or M2 stimulation. We identified differentially expressed genes by iAs in a sex- and stimulation-dependent manner and used bioinformatics tools to predict protein-protein interactions, transcriptional regulatory networks, and associated biological processes. Overall, our data suggest that M1-stimulated, especially female-derived, BMDMs are most susceptible to iAs exposure. Most notably, we observed significant downregulation of major proinflammatory transcription factors, like IRF8, and its downstream targets, as well as genes encoding proteins involved in pattern recognition and antigen presentation, such as TLR7, TLR8, and H2-D1, potentially providing causal insight regarding arsenic's role in perturbing immune responses to infectious diseases. We also observed significant downregulation of genes involved in processes crucial to coordinating a proinflammatory response including leukocyte migration, differentiation, and cytokine and chemokine production and response. Finally, we discovered that 24 X-linked genes were dysregulated in iAs-exposed female stimulation groups compared to only 3 across the iAs-exposed male stimulation groups. These findings elucidate the potential mechanisms underlying the sex-differential iAs-associated immune-related disease risk.
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7
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Sehar S, Adil MF, Askri SMH, Feng Q, Wei D, Sahito FS, Shamsi IH. Pan-transcriptomic Profiling Demarcates Serendipita Indica-Phosphorus Mediated Tolerance Mechanisms in Rice Exposed to Arsenic Toxicity. RICE (NEW YORK, N.Y.) 2023; 16:28. [PMID: 37354226 DOI: 10.1186/s12284-023-00645-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 06/10/2023] [Indexed: 06/26/2023]
Abstract
Inadvertent accumulation of arsenic (As) in rice (Oryza sativa L.) is a concern for people depending on it for their subsistence, as it verily causes epigenetic alterations across the genome as well as in specific cells. To ensure food safety, certain attempts have been made to nullify this highest health hazard encompassing physiological, chemical and biological methods. Albeit, the use of mycorrhizal association along with nutrient reinforcement strategy has not been explored yet. Mechanisms of response and resistance of two rice genotypes to As with or without phosphorus (P) nutrition and Serendipita indica (S. indica; S.i) colonization were explored by root transcriptome profiling in the present study. Results revealed that the resistant genotype had higher auxin content and root plasticity, which helped in keeping the As accumulation and P starvation response to a minimum under alone As stress. However, sufficient P supply and symbiotic relationship switched the energy resources towards plant's developmental aspects rather than excessive root proliferation. Higher As accumulating genotype (GD-6) displayed upregulation of ethylene signaling/biosynthesis, root stunting and senescence related genes under As toxicity. Antioxidant defense system and cytokinin biosynthesis/signaling of both genotypes were strengthened under As + S.i + P, while the upregulation of potassium (K) and zinc (Zn) transporters depicted underlying cross-talk with iron (Fe) and P. Differential expression of phosphate transporters, peroxidases and GSTs, metal detoxification/transport proteins, as well as phytohormonal metabolism were responsible for As detoxification. Taken together, S. indica symbiosis fortified with adequate P-fertilizer can prove to be effective in minimizing As acquisition and accumulation in rice plants.
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Affiliation(s)
- Shafaque Sehar
- Zhejiang Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Muhammad Faheem Adil
- Zhejiang Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Syed Muhammad Hassan Askri
- Zhejiang Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Qidong Feng
- Zhejiang Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Dongming Wei
- Zhejiang Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Falak Sehar Sahito
- Dow International Medical College, Dow University of Health Sciences, Karachi, 74200, Pakistan
| | - Imran Haider Shamsi
- Zhejiang Key Laboratory of Crop Germplasm Resource, Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou, 310058, China.
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8
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Li S, Dong X, Xu L, Wu Z. Nephroprotective Effects of Selenium Nanoparticles Against Sodium Arsenite-Induced Damages. Int J Nanomedicine 2023; 18:3157-3176. [PMID: 37333733 PMCID: PMC10276609 DOI: 10.2147/ijn.s413362] [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: 03/20/2023] [Accepted: 05/25/2023] [Indexed: 06/20/2023] Open
Abstract
Introduction The potential effects of selenium nanoparticles (SeNPs) administration on arsenic exposure-mediated nephrotoxicity by alleviating fibrosis, inflammation, oxidative stress-related damage, and apoptosis remains more detailed investigations. Methods After the synthesis of selenium nanoparticles (SeNPs) by sodium selenite (Na2SeO3) through a versatile and green procedure, the biosafety of SeNPs was assessed by assaying renal functions and inflammation in mice. Subsequently, nephroprotective effects of SeNPs against sodium arsenite (NaAsO2)-induced damages were confirmed by biochemical, molecular, and histopathological assays, including renal function, histological lesion, fibrosis, inflammation, oxidative stress-related damage, and apoptosis in mice renal tissues and renal tubular duct epithelial cells (HK2 cells). Results The excellent biocompatibility and safety of SeNPs prepared in this study were confirmed by the non-significant differences in the renal functions and inflammation levels in mice between the negative control (NC) and 1 mg/kg SeNPs groups (p>0.05). The results of biochemical, molecular, and histopathological assays confirmed that daily administration of 1 mg/kg SeNPs for 4 weeks not only ameliorated renal dysfunctions and injuries caused by NaAsO2 exposure but also inhibited the fibrosis, inflammation, oxidative stress-related damage, and apoptosis in the renal tissues of NaAsO2-exposed mice. In addition, altered viability, inflammation, oxidative stress-related damage, and apoptosis in the NaAsO2-exposed HK2 cells were effectively reversed after 100 μg/mL SeNPs supplementation. Conclusion Our findings authentically confirmed the biosafety and nephroprotective effects of SeNPs against NaAsO2 exposure-induced damages by alleviating inflammation, oxidative stress-related damage, and apoptosis.
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Affiliation(s)
- Shubin Li
- Department of Geriatric Medical Center, Inner Mongolia People’s Hospital, Hohhot, 010021, People’s Republic of China
| | - Xingna Dong
- Department of Geriatric Medical Center, Inner Mongolia People’s Hospital, Hohhot, 010021, People’s Republic of China
| | - Limeng Xu
- Department of Geriatric Medical Center, Inner Mongolia People’s Hospital, Hohhot, 010021, People’s Republic of China
| | - Zhenli Wu
- Department of Geriatric Medical Center, Inner Mongolia People’s Hospital, Hohhot, 010021, People’s Republic of China
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George S, Cassidy RN, Saintilnord WN, Fondufe-Mittendorf Y. Epigenomic reprogramming in iAs-mediated carcinogenesis. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2022; 96:319-365. [PMID: 36858778 DOI: 10.1016/bs.apha.2022.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
Abstract
Arsenic is a naturally occurring metal carcinogen found in the Earth's crust. Millions of people worldwide are chronically exposed to arsenic through drinking water and food. Exposure to inorganic arsenic has been implicated in many diseases ranging from acute toxicities to malignant transformations. Despite the well-known deleterious health effects of arsenic exposure, the molecular mechanisms in arsenic-mediated carcinogenesis are not fully understood. Since arsenic is non-mutagenic, the mechanism by which arsenic causes carcinogenesis is via alterations in epigenetic-regulated gene expression. There are two possible ways by which arsenic may modify the epigenome-indirectly through an arsenic-induced generation of reactive oxygen species which then impacts chromatin remodelers, or directly through interaction and modulation of chromatin remodelers. Whether directly or indirectly, arsenic modulates epigenetic gene regulation and our understanding of the direct effect of this modulation on chromatin structure is limited. In this chapter we will discuss the various ways by which inorganic arsenic affects the epigenome with consequences in health and disease.
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Affiliation(s)
- Smitha George
- Department of Epigenetics, Van Andel Institute, Grand Rapids, MI, United States
| | - Richard N Cassidy
- Department of Epigenetics, Van Andel Institute, Grand Rapids, MI, United States
| | - Wesley N Saintilnord
- Department of Epigenetics, Van Andel Institute, Grand Rapids, MI, United States; Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, United States
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10
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Ghosh A, Mukherjee S, Roy M. Black tea extract prevents inorganic arsenic induced uncontrolled proliferation, epithelial to mesenchymal transition and induction of metastatic properties in HaCaT keratinocytes - an in vitro study. Toxicol In Vitro 2022; 85:105478. [PMID: 36122807 DOI: 10.1016/j.tiv.2022.105478] [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: 07/11/2022] [Revised: 09/07/2022] [Accepted: 09/13/2022] [Indexed: 10/14/2022]
Abstract
A major global problem is chronic exposure to inorganic arsenic (iAs) which causes various health hazards including cancer. Escalation of reactive oxygen species (ROS) generation by chronic iAs exposure promotes Epithelial to Mesenchymal transition (EMT) which is followed by metastatic progression. In the present study, skin keratinocyte cells (HaCaT) were divided into three groups: (i) untreated, (ii) chronically iAs exposed, (iii) black tea extract (BTE) along with iAs treated. ROS was estimated by flowcytometry, expression of EMT markers were assessed by flowcytometry, western-blotting and Immunofluorescence. For metastatic studies, wound-healing assay, gelatin zymography, western-blot, transwell migration/invasion assay had been performed. Long term exposure of HaCaT cells to iAs causes excess generation of ROS. Morphological transformation and EMT were apparent at 210 days of exposure. Development of metastatic characteristics were observed at 240 days. Alterations in the parameters induced by iAs were found to be ameliorated by BTE. BTE was found to quench excess generation of ROS by iAs, subsequently inhibiting the chain of events like EMT and metastasis. Therefore, BTE may be considered as a potential phytochemical to prevent the deleterious effect of iAs. Skin carcinogenesis induced by iAs may thus be prevented by BTE via inhibition of EMT.
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Affiliation(s)
- Archismaan Ghosh
- Dept. Environmental Carcinogenesis & Toxicology, Chittaranjan National Cancer Institute, 37, S P Mukherjee Road, Kolkata 700019, India
| | - Sutapa Mukherjee
- Dept. Environmental Carcinogenesis & Toxicology, Chittaranjan National Cancer Institute, 37, S P Mukherjee Road, Kolkata 700019, India
| | - Madhumita Roy
- Dept. Environmental Carcinogenesis & Toxicology, Chittaranjan National Cancer Institute, 37, S P Mukherjee Road, Kolkata 700019, India.
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11
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Upamalika SWAM, Wannige CT, Vidanagamachchi SM, Gunasekara SC, Kolli RT, De Silva PMCS, Kulasiri D, Jayasundara N. A review of molecular mechanisms linked to potential renal injury agents in tropical rural farming communities. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2022; 92:103850. [PMID: 35301132 DOI: 10.1016/j.etap.2022.103850] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 03/09/2022] [Accepted: 03/11/2022] [Indexed: 06/14/2023]
Abstract
The chronic kidney disease of unknown etiology (CKDu) is a global health concern primarily impacting tropical farming communities. Although the precise etiology is debated, CKDu is associated with environmental exposures including heat stress and chemical contaminants such as fluoride, heavy metals, and herbicide glyphosate. However, a comprehensive synthesis is lacking on molecular networks underpinning renal damage induced by these factors. Addressing this gap, here we present key molecular events associated with heat and chemical exposures. We identified that caspase activation and lipid peroxidation are common endpoints of glyphosate exposure, while vasopressin and polyol pathways are associated with heat stress and dehydration. Heavy metal exposure is shown to induce lipid peroxidation and endoplasmic reticulum stress from ROS activated MAPK, NFĸB, and caspase. Collectively, we identify that environmental exposure induced increased cellular oxidative stress as a common mechanism mediating renal cell inflammation, apoptosis, and necrosis, likely contributing to CKDu initiation and progression.
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Affiliation(s)
| | | | | | | | - Ramya Tulasi Kolli
- Nicholas School of the Environment, Duke University, NC 27708, United States.
| | | | - Don Kulasiri
- Department of Molecular Biosciences, and Centre for Advanced Computational Solutions (C-fACS), Lincoln University, New Zealand.
| | - Nishad Jayasundara
- Nicholas School of the Environment, Duke University, NC 27708, United States.
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12
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Manić L, Wallace D, Onganer PU, Taalab YM, Farooqi AA, Antonijević B, Buha Djordjevic A. Epigenetic mechanisms in metal carcinogenesis. Toxicol Rep 2022; 9:778-787. [PMID: 36561948 PMCID: PMC9764177 DOI: 10.1016/j.toxrep.2022.03.037] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 02/16/2022] [Accepted: 03/26/2022] [Indexed: 12/25/2022] Open
Abstract
Many metals exhibit genotoxic and/or carcinogenic effects. These toxic metals can be found ubiquitously - in drinking water, food, air, general use products, in everyday and occupational settings. Exposure to such carcinogenic metals can result in serious health disorders, including cancer. Arsenic, cadmium, chromium, nickel, and their compounds have already been recognized as carcinogens by the International Agency for Research on Cancer. This review summarizes a wide range of epigenetic mechanisms contributing to carcinogenesis induced by these metals, primarily including, but not limited to, DNA methylation, miRNA regulation, and histone posttranslational modifications. The mechanisms are described and discussed both from a metal-centric and a mechanism-centric standpoint. The review takes a broad perspective, putting the mechanisms in the context of real-life exposure, and aims to assist in guiding future research, particularly with respect to the assessment and control of exposure to carcinogenic metals and novel therapy development.
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Affiliation(s)
- Luka Manić
- Department of Toxicology “Akademik Danilo Soldatović”, Faculty of Pharmacy, University of Belgrade, Belgrade, Serbia
| | - David Wallace
- School of Biomedical Science, Oklahoma State University Center for Health Sciences, Tulsa, United States
| | - Pinar Uysal Onganer
- Cancer Research Group, School of Life Sciences, University of Westminster, London, UK
| | - Yasmeen M. Taalab
- Institute of Forensic and Traffic Medicine, University of Heidelberg, Voßstraße 2, 69115 Heidelberg, Germany,Forensic Medicine and Clinical Toxicology Department, Faculty of Medicine, Mansoura University, Dakahlia Governate 35516, Egypt
| | - Ammad Ahmad Farooqi
- Laboratory for Translational Oncology and Personalized Medicine, RLMC, Lahore, Pakistan
| | - Biljana Antonijević
- Department of Toxicology “Akademik Danilo Soldatović”, Faculty of Pharmacy, University of Belgrade, Belgrade, Serbia
| | - Aleksandra Buha Djordjevic
- Department of Toxicology “Akademik Danilo Soldatović”, Faculty of Pharmacy, University of Belgrade, Belgrade, Serbia,Correspondence to: Department of Toxicology “Akademik Danilo Soldatović”, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11221 Belgrade, Serbia.
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13
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Ferragut Cardoso AP, Banerjee M, Al-Eryani L, Sayed M, Wilkey DW, Merchant ML, Park JW, States JC. Temporal Modulation of Differential Alternative Splicing in HaCaT Human Keratinocyte Cell Line Chronically Exposed to Arsenic for up to 28 Wk. ENVIRONMENTAL HEALTH PERSPECTIVES 2022; 130:17011. [PMID: 35072517 PMCID: PMC8785870 DOI: 10.1289/ehp9676] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
BACKGROUND Chronic arsenic exposure via drinking water is associated with an increased risk of developing cancer and noncancer chronic diseases. Pre-mRNAs are often subject to alternative splicing, generating mRNA isoforms encoding functionally distinct protein isoforms. The resulting imbalance in isoform species can result in pathogenic changes in critical signaling pathways. Alternative splicing as a mechanism of arsenic-induced toxicity and carcinogenicity is understudied. OBJECTIVE This study aimed to accurately profile differential alternative splicing events in human keratinocytes induced by chronic arsenic exposure that might play a role in carcinogenesis. METHODS Independent quadruplicate cultures of immortalized human keratinocytes (HaCaT) were maintained continuously for 28 wk with 0 or 100 nM sodium arsenite. RNA-sequencing (RNA-Seq) was performed with poly(A) RNA isolated from cells harvested at 7, 19, and 28 wk with subsequent replicate multivariate analysis of transcript splicing (rMATS) analysis to detect and quantify differential alternative splicing events. Reverse transcriptase-polymerase chain reaction (RT-PCR) for selected alternative splicing events was performed to validate RNA-Seq predictions. Functional enrichment was performed by gene ontology (GO) analysis of the differential alternative splicing event data set at each time point. RESULTS At least 600 differential alternative splicing events were detected at each time point tested, comprising all the five main types of alternative splicing and occurring in both open reading frames (ORFs) and untranslated regions (UTRs). Based on functional relevance ELK4, SHC1, and XRRA1 were selected for validation of predicted alternative splicing events at 7 wk by RT-PCR. Densitometric analysis of RT-PCR data corroborated the rMATS predicted alternative splicing for all three events. Protein expression validation of the selected alternative splicing events was challenging given that very few isoform-specific antibodies are available. GO analysis demonstrated that the enriched terms in differential alternatively spliced mRNAs changed dynamically with the time of exposure. Notably, RNA metabolism and splicing regulation pathways were enriched at the 7-wk time point, when the greatest number of differentially alternatively spliced mRNAs are detected. Our preliminary proteomic analysis demonstrated that the expression of the canonical isoforms of the splice regulators DDX42, RMB25, and SRRM2 were induced upon chronic arsenic exposure, corroborating the splicing predictions. DISCUSSION These results using cultures of HaCaT cells suggest that arsenic exposure disrupted an alternative splice factor network and induced time-dependent genome-wide differential alternative splicing that likely contributed to the changing proteomic landscape in arsenic-induced carcinogenesis. However, significant challenges remain in corroborating alternative splicing data at the proteomic level. https://doi.org/10.1289/EHP9676.
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Affiliation(s)
- Ana P. Ferragut Cardoso
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky, USA
| | - Mayukh Banerjee
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky, USA
| | - Laila Al-Eryani
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky, USA
| | - Mohammed Sayed
- Computer Science and Engineering, University of Louisville, Louisville, Kentucky, USA
| | - Daniel W. Wilkey
- Division of Nephrology & Hypertension, Department of Medicine, University of Louisville, Louisville, Kentucky, USA
| | - Michael L. Merchant
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky, USA
- Division of Nephrology & Hypertension, Department of Medicine, University of Louisville, Louisville, Kentucky, USA
| | - Juw W. Park
- Computer Science and Engineering, University of Louisville, Louisville, Kentucky, USA
- KY INBRE Bioinformatics Core, University of Louisville, Louisville, Kentucky, USA
| | - J. Christopher States
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky, USA
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14
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Saintilnord WN, Fondufe-Mittendorf Y. Arsenic-induced epigenetic changes in cancer development. Semin Cancer Biol 2021; 76:195-205. [PMID: 33798722 PMCID: PMC8481342 DOI: 10.1016/j.semcancer.2021.03.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 03/22/2021] [Accepted: 03/23/2021] [Indexed: 12/29/2022]
Abstract
Arsenic is a ubiquitous metalloid whose high levels of toxicity pose major health concerns to millions of people worldwide by increasing susceptibility to various cancers and non-cancer illnesses. Since arsenic is not a mutagen, the mechanism by which it causes changes in gene expression and disease pathogenesis is not clear. One possible mechanism is through generation of reactive oxygen species. Another equally important mechanism still very much in its infancy is epigenetic dysregulation. In this review, we discuss recent discoveries underlying arsenic-induced epigenetic changes in cancer development. Importantly, we highlight the proposed mechanisms targeted by arsenic to drive oncogenic gene expression.
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Affiliation(s)
- Wesley N Saintilnord
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, USA.
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15
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Stýblo M, Venkatratnam A, Fry RC, Thomas DJ. Origins, fate, and actions of methylated trivalent metabolites of inorganic arsenic: progress and prospects. Arch Toxicol 2021; 95:1547-1572. [PMID: 33768354 DOI: 10.1007/s00204-021-03028-w] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 03/11/2021] [Indexed: 12/16/2022]
Abstract
The toxic metalloid inorganic arsenic (iAs) is widely distributed in the environment. Chronic exposure to iAs from environmental sources has been linked to a variety of human diseases. Methylation of iAs is the primary pathway for metabolism of iAs. In humans, methylation of iAs is catalyzed by arsenic (+ 3 oxidation state) methyltransferase (AS3MT). Conversion of iAs to mono- and di-methylated species (MAs and DMAs) detoxifies iAs by increasing the rate of whole body clearance of arsenic. Interindividual differences in iAs metabolism play key roles in pathogenesis of and susceptibility to a range of disease outcomes associated with iAs exposure. These adverse health effects are in part associated with the production of methylated trivalent arsenic species, methylarsonous acid (MAsIII) and dimethylarsinous acid (DMAsIII), during AS3MT-catalyzed methylation of iAs. The formation of these metabolites activates iAs to unique forms that cause disease initiation and progression. Taken together, the current evidence suggests that methylation of iAs is a pathway for detoxification and for activation of the metalloid. Beyond this general understanding of the consequences of iAs methylation, many questions remain unanswered. Our knowledge of metabolic targets for MAsIII and DMAsIII in human cells and mechanisms for interactions between these arsenicals and targets is incomplete. Development of novel analytical methods for quantitation of MAsIII and DMAsIII in biological samples promises to address some of these gaps. Here, we summarize current knowledge of the enzymatic basis of MAsIII and DMAsIII formation, the toxic actions of these metabolites, and methods available for their detection and quantification in biomatrices. Major knowledge gaps and future research directions are also discussed.
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Affiliation(s)
- Miroslav Stýblo
- Department of Nutrition, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
| | - Abhishek Venkatratnam
- Department of Nutrition, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
- Department of Environmental Science and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Rebecca C Fry
- Department of Environmental Science and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - David J Thomas
- Chemical Characterization and Exposure Division, Center for Computational Toxicology and Exposure, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, 27709, USA.
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16
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Ferragut Cardoso AP, Udoh KT, States JC. Arsenic-induced changes in miRNA expression in cancer and other diseases. Toxicol Appl Pharmacol 2020; 409:115306. [PMID: 33127375 PMCID: PMC7772821 DOI: 10.1016/j.taap.2020.115306] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 10/20/2020] [Accepted: 10/26/2020] [Indexed: 02/06/2023]
Abstract
miRNAs (miRNA) are essential players regulating gene expression affecting cellular processes contributing to disease development. Dysregulated miRNA expression has been observed in numerous diseases including hepatitis, cardiovascular diseases and cancers. In cardiovascular diseases, several miRNAs function as mediators of pathogenic stress-related signaling pathways that may lead to an excessive extracellular matrix production and collagen deposition causing cardiac stress resulting in fibrosis. In cancers, many miRNAs function as oncogenes or tumor suppressors facilitating tumor growth, invasion and angiogenesis. Furthermore, the association between distinct miRNA profile and tumor development, progression and treatment response has identified miRNAs as potential biomarkers for disease diagnosis and prognosis. Growing evidence demonstrates changes in miRNA expression levels in experimental settings or observational studies associated with environmental chemical exposures such as arsenic. Arsenic is one of the most well-known human carcinogens. Long-term exposure through drinking water increases risk of developing skin, lung and urinary bladder cancers, as well as cardiovascular disease. The mechanism(s) by which arsenic causes disease remains elusive. Proposed mechanisms include miRNA dysregulation. Epidemiological studies identified differential miRNA expression between arsenic-exposed and non-exposed individuals from India, Bangladesh, China and Mexico. In vivo and in vitro studies have shown that miRNAs are critically involved in arsenic-induced malignant transformation. Few studies analyzed miRNAs in other diseases associated with arsenic exposure. Importantly, there is no consensus on a consistent miRNA profile for arsenic-induced cancers because most studies analyze only particular miRNAs. Identifying miRNA expression changes common among humans, rodents and cell lines might guide future miRNA investigations.
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Affiliation(s)
- Ana P Ferragut Cardoso
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY 40202, USA
| | - Karen T Udoh
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY 40202, USA
| | - J Christopher States
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY 40202, USA.
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17
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Abstract
Metal exposure is pervasive and not limited to sporadic poisoning events or toxic waste sites. Hundreds of millions of people around the globe are affected by chronic metal exposure, which is associated with serious health concerns, including cancer, as demonstrated in a variety of studies at the molecular, systemic, and epidemiologic levels. Metal-induced toxicity and carcinogenicity are sophisticated and complex in nature. This review provides a broad context and holistic view of currently available studies on the mechanisms of metal-induced carcinogenesis. Specifically, we focus on the five most prevalent carcinogenic metals, arsenic, nickel, cadmium, chromium, and beryllium, and their potential to drive carcinogenesis in humans. A comprehensive understanding of the mechanisms behind the development of metal-induced cancer can provide valuable insights for therapeutic intervention involving molecular targets in metal-induced carcinogenesis.
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Affiliation(s)
- Qiao Yi Chen
- Departments of Environmental Medicine, and Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10010, USA;
| | - Thomas DesMarais
- Departments of Environmental Medicine, and Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10010, USA;
| | - Max Costa
- Departments of Environmental Medicine, and Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10010, USA;
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18
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Banerjee M, Ferragut Cardoso AP, Lykoudi A, Wilkey DW, Pan J, Watson WH, Garbett NC, Rai SN, Merchant ML, States JC. Arsenite Exposure Displaces Zinc from ZRANB2 Leading to Altered Splicing. Chem Res Toxicol 2020; 33:1403-1417. [PMID: 32274925 DOI: 10.1021/acs.chemrestox.9b00515] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Exposure to arsenic, a class I carcinogen, affects 200 million people globally. Skin is the major target organ, but the molecular etiology of arsenic-induced skin carcinogenesis remains unclear. Arsenite (As3+)-induced disruption of alternative splicing could be involved, but the mechanism is unknown. Zinc finger proteins play key roles in alternative splicing. As3+ can displace zinc (Zn2+) from C3H1 and C4 zinc finger motifs (zfm's), affecting protein function. ZRANB2, an alternative splicing regulator with two C4 zfm's integral to its structure and splicing function, was chosen as a candidate for this study. We hypothesized that As3+ could displace Zn2+ from ZRANB2, altering its structure, expression, and splicing function. As3+/Zn2+ binding and mutual displacement experiments were performed with synthetic apo-peptides corresponding to each ZRANB2 zfm, employing a combination of intrinsic fluorescence, ultraviolet spectrophotometry, zinc colorimetric assay, and liquid chromatography-tandem mass spectrometry. ZRANB2 expression in HaCaT cells acutely exposed to As3+ (0 or 5 μM, 0-72 h; or 0-5 μM, 6 h) was examined by RT-qPCR and immunoblotting. ZRANB2-dependent splicing of TRA2B mRNA, a known ZRANB2 target, was monitored by reverse transcription-polymerase chain reaction. As3+ bound to, as well as displaced Zn2+ from, each zfm. Also, Zn2+ displaced As3+ from As3+-bound zfm's acutely, albeit transiently. As3+ exposure induced ZRANB2 protein expression between 3 and 24 h and at all exposures tested but not ZRANB2 mRNA expression. ZRANB2-directed TRA2B splicing was impaired between 3 and 24 h post-exposure. Furthermore, ZRANB2 splicing function was also compromised at all As3+ exposures, starting at 100 nm. We conclude that As3+ exposure displaces Zn2+ from ZRANB2 zfm's, changing its structure and compromising splicing of its targets, and increases ZRANB2 protein expression as a homeostatic response both at environmental/toxicological exposures and therapeutically relevant doses.
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Affiliation(s)
- Mayukh Banerjee
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202, United States
| | - Ana P Ferragut Cardoso
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202, United States
| | - Angeliki Lykoudi
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202, United States
| | - Daniel W Wilkey
- Division of Nephrology & Hypertension, Department of Medicine, University of Louisville, Louisville, Kentucky 40202, United States
| | - Jianmin Pan
- Biostatistics and Bioinformatics Facility, James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky 40202, United States
| | - Walter H Watson
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202, United States.,Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, University of Louisville, Louisville, Kentucky 40202, United States
| | - Nichola C Garbett
- Division of Medical Oncology and Hematology, Department of Medicine, University of Louisville, Louisville, Kentucky 40202, United States.,James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky 40202, United States
| | - Shesh N Rai
- Biostatistics and Bioinformatics Facility, James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky 40202, United States.,Department of Bioinformatics and Biostatistics, University of Louisville, Louisville, Kentucky 40202, United States
| | - Michael L Merchant
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202, United States.,Division of Nephrology & Hypertension, Department of Medicine, University of Louisville, Louisville, Kentucky 40202, United States
| | - J Christopher States
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202, United States
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19
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Rinfret Robert C, McManus FP, Lamoliatte F, Thibault P. Interplay of Ubiquitin-Like Modifiers Following Arsenic Trioxide Treatment. J Proteome Res 2020; 19:1999-2010. [PMID: 32223133 DOI: 10.1021/acs.jproteome.9b00807] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Arsenic trioxide (ATO) is a therapeutic agent used to treat acute promyelocytic leukemia (APL), a disease caused by a chromosomal translocation of the retinoic acid receptor α (RARα) gene that can occur reciprocally with the promyelocytic leukemia (PML) gene. The mechanisms through which ATO exerts its effects on cells are not fully characterized though they involve the SUMOylation, the ubiquitylation, and the degradation of the PML/RARα oncoprotein through the PML moiety. To better understand the mechanisms that underlie the cytotoxicity induced with increasing ATO levels, we profiled the changes in protein SUMOylation, phosphorylation, and ubiquitylation on HEK293 cells following exposure to low (1 μM) or elevated (10 μM) ATO for 4 h. Our analyses revealed that a low dose of ATO resulted in the differential modification of selected substrates including the SUMOylation (K380, K394, K490, and K497) and ubiquitylation (K337, K401) of PML. These experiments also highlighted a number of unexpected SUMOylated substrates involved in DNA damage response (e.g., PCNA, YY1, and poly[ADP-ribose] polymerase 1 (PARP1)) and messenger RNA (mRNA) splicing (e.g., ACIN1, USP39, and SART1) that were regulated at higher ATO concentrations. Interestingly, additional enzymatic assays revealed that SUMOylation of PARP1 impeded its proteolytic cleavage by caspase-3, suggesting that SUMOylation could have a protective role in delaying cell apoptosis.
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Affiliation(s)
- Clémence Rinfret Robert
- Institute for Research in Immunology and Cancer, Montreal, Québec H3T 1J4, Canada.,Department of Biochemistry, University of Montréal, Montreal, Québec H3T 1J4, Canada
| | - Francis P McManus
- Institute for Research in Immunology and Cancer, Montreal, Québec H3T 1J4, Canada
| | - Frédéric Lamoliatte
- Institute for Research in Immunology and Cancer, Montreal, Québec H3T 1J4, Canada.,Department of Chemistry, University of Montréal, P.O. Box 6128, Station Centre-Ville, Montreal, Québec H3T 1J4, Canada
| | - Pierre Thibault
- Institute for Research in Immunology and Cancer, Montreal, Québec H3T 1J4, Canada.,Department of Biochemistry, University of Montréal, Montreal, Québec H3T 1J4, Canada.,Department of Chemistry, University of Montréal, P.O. Box 6128, Station Centre-Ville, Montreal, Québec H3T 1J4, Canada
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20
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Sphingosine kinase and p38 MAP kinase signaling promote resistance to arsenite-induced lethality in Caenorhabditis elegan. Mol Cell Toxicol 2019. [DOI: 10.1007/s13273-019-0045-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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21
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Cardoso APF, Al-Eryani L, States JC. Arsenic-Induced Carcinogenesis: The Impact of miRNA Dysregulation. Toxicol Sci 2019; 165:284-290. [PMID: 29846715 DOI: 10.1093/toxsci/kfy128] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Arsenic is a toxic metalloid widely present in the earth's crust, and is a proven human carcinogen. Chronic arsenic exposure mainly through drinking water causes skin, lung, and urinary bladder cancers, and is associated with liver, prostate, and kidney cancers, cardiovascular and neurological disorders, and diabetes. Several modes of action have been suggested in arsenic carcinogenesis. However, the molecular etiology of arsenic-induced cancer remains unclear. Recent evidence clearly indicates that gene expression modifications induced by arsenic may involve epigenetic alterations, including miRNA dysregulation. Many miRNAs have been implicated in different human cancers as a consequence of losses and or gains of miRNA function that contribute to cancer development. Progress in identifying miRNA dysregulation induced by arsenic has been made using different approaches and models. The present review discusses the recent data regarding dysregulated expression of miRNA in arsenic-induced malignant transformation in vitro, gaps in current understanding and deficiencies in current models for arsenic-induced carcinogenesis, and future directions of research that would improve our knowledge regarding the mechanisms involved in arsenic-induced carcinogenesis.
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Affiliation(s)
- Ana P Ferragut Cardoso
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202
| | - Laila Al-Eryani
- DNA Repair Section, Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4262
| | - J Christopher States
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky 40202
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22
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Sinha D, Prasad P. Health effects inflicted by chronic low-level arsenic contamination in groundwater: A global public health challenge. J Appl Toxicol 2019; 40:87-131. [PMID: 31273810 DOI: 10.1002/jat.3823] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 04/28/2019] [Indexed: 01/23/2023]
Abstract
Groundwater arsenic (As) contamination is a global public health concern. The high level of As exposure (100-1000 μg/L or even higher) through groundwater has been frequently associated with serious public health hazards, e.g., skin disorders, cardiovascular diseases, respiratory problems, complications of gastrointestinal tract, liver and splenic ailments, kidney and bladder disorders, reproductive failure, neurotoxicity and cancer. However, reviews on low-level As exposure and the imperative health effects are far less documented. The World Health Organization (WHO) and the United States Environmental Protection Agency (USEPA) has set the permissible standard of As in drinking water at 10 μg/L. Considering the WHO and USEPA guidelines, most of the developed countries have established standards at or below this guideline. Worldwide many countries including India have millions of aquifers with low-level As contamination (≤50 μg/L). The exposed population of these areas might not show any As-related skin lesions (hallmark of As toxicity particularly in a population consuming As contaminated groundwater >300 μg/L) but might be subclinically affected. This review has attempted to encompass the wide range of health effects associated with chronic low-level As exposure ≤50 μg/L and the probable mechanisms that might provide a better insight regarding the underlying cause of these clinical manifestations. Therefore, there is an urgent need to create mass awareness about the health effects of chronic low-level As exposure and planning of proper mitigation strategies.
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Affiliation(s)
- Dona Sinha
- Receptor Biology and Tumor Metastasis, Chittaranjan National Cancer Institute, Kolkata, India
| | - Priyanka Prasad
- Receptor Biology and Tumor Metastasis, Chittaranjan National Cancer Institute, Kolkata, India
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23
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Wei S, Zhang H, Tao S. A review of arsenic exposure and lung cancer. Toxicol Res (Camb) 2019; 8:319-327. [PMID: 31160966 PMCID: PMC6505385 DOI: 10.1039/c8tx00298c] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 01/22/2019] [Indexed: 12/27/2022] Open
Abstract
As a well-established human carcinogen, arsenic has increased the risk of lung cancer over the past decades. Wide exposure to arsenic in the environment has attracted the attention of scientists. Its carcinogenicity at early life stages has been observed in certain animal studies already, yet current evidence is insufficient to extrapolate this to humans. Although the mechanisms of lung cancer induced by arsenic remain unclear, most of them are related to the biotransformation of arsenic, which would further provide target sites for precaution and therapy. This review comprehensively summarizes current studies associated to arsenic exposure and lung cancer and the mechanism of its carcinogenesis in lung cancer in three sections, namely, epidemiological studies, experimental studies, and mechanistic studies. In addition, prevention and treatment strategies as well as directions for future studies are discussed.
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Affiliation(s)
- Shuhui Wei
- School of Public Health , Medical College of Soochow University , 199 Ren'ai Road , Suzhou 215123 , Jiangsu , China . ; ; Tel: +86-512-65698540
| | - Hong Zhang
- School of Public Health , Medical College of Soochow University , 199 Ren'ai Road , Suzhou 215123 , Jiangsu , China . ; ; Tel: +86-512-65698540
| | - Shasha Tao
- School of Public Health , Medical College of Soochow University , 199 Ren'ai Road , Suzhou 215123 , Jiangsu , China . ; ; Tel: +86-512-65698540
- Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Disease , School of Public Health , Soochow University , Suzhou , 215123 , PR China
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24
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Histone stress: an unexplored source of chromosomal instability in cancer? Curr Genet 2019; 65:1081-1088. [DOI: 10.1007/s00294-019-00967-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 02/27/2019] [Accepted: 04/03/2019] [Indexed: 01/24/2023]
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25
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Selmin OI, Donovan MG, Skovan B, Paine-Murieta GD, Romagnolo DF. Arsenic‑induced BRCA1 CpG promoter methylation is associated with the downregulation of ERα and resistance to tamoxifen in MCF7 breast cancer cells and mouse mammary tumor xenografts. Int J Oncol 2019; 54:869-878. [PMID: 30664189 PMCID: PMC6365020 DOI: 10.3892/ijo.2019.4687] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 12/03/2018] [Indexed: 02/07/2023] Open
Abstract
A significant percentage (~30%) of estrogen receptor-α (ERα)-positive tumors become refractory to endocrine therapies; however, the mechanisms responsible for this resistance remain largely unknown. Chronic exposure to arsenic through foods and contaminated water has been linked to an increased incidence of several tumors and long-term health complications. Preclinical and population studies have indicated that arsenic exposure may interfere with endocrine regulation and increase the risk of breast tumorigenesis. In this study, we examined the effects of sodium arsenite (NaAsIII) exposure in ERα-positive breast cancer cells in vitro and in mammary tumor xenografts. The results revealed that acute (within 4 days) and long-term (10 days to 7 weeks) in vitro exposure to environmentally relevant doses reduced breast cancer 1 (BRCA1) and ERα expression associated with the gain of cyclin D1 (CCND1) and folate receptor 1 (FOLR1), and the loss of methylenetetrahydrofolate reductase (MTHFR) expression. Furthermore, long-term exposure to NaAsIII induced the proliferation and compromised the response of MCF7 cells to tamoxifen (TAM). The in vitro exposure to NaAsIII induced BRCA1 CpG methylation associated with the increased recruitment of DNA methyltransferase 1 (DNMT1) and the loss of RNA polymerase II (PolII) at the BRCA1 gene. Xenografts of NaAsIII-preconditioned MCF7 cells (MCF7NaAsIII) into the mammary fat pads of nude mice produced a larger tumor volume compared to tumors from control MCF7 cells and were more refractory to TAM in association with the reduced expression of BRCA1 and ERα, CpG hypermethylation of estrogen receptor 1 (ESR1) and BRCA1, and the increased expression of FOLR1. These cumulative data support the hypothesis that exposure to AsIII may contribute to reducing the efficacy of endocrine therapy against ERα-positive breast tumors by hampering the expression of ERα and BRCA1 via CpG methylation, respectively of ESR1 and BRCA1.
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Affiliation(s)
- Ornella I Selmin
- The University of Arizona Cancer Center, The University of Arizona, Tucson, AZ 85724, USA
| | - Micah G Donovan
- Cancer Biology Graduate Interdisciplinary Program, The University of Arizona, Tucson, AZ 85724, USA
| | - Bethany Skovan
- The University of Arizona Cancer Center, The University of Arizona, Tucson, AZ 85724, USA
| | | | - Donato F Romagnolo
- The University of Arizona Cancer Center, The University of Arizona, Tucson, AZ 85724, USA
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26
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Ramos-Treviño J, Bassol-Mayagoitia S, Hernández-Ibarra JA, Ruiz-Flores P, Nava-Hernández MP. Toxic Effect of Cadmium, Lead, and Arsenic on the Sertoli Cell: Mechanisms of Damage Involved. DNA Cell Biol 2018; 37:600-608. [PMID: 29746152 DOI: 10.1089/dna.2017.4081] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Over the past decades, an increase has been described in exposure to environmental toxins; consequently, a series of studies has been carried out with the aim of identifying problems associated with health. One of the main risk factors is exposure to heavy metals. The adverse effects that these compounds exert on health are quite complex and difficult to elucidate, in that they act at different levels and there are various signaling pathways that are implicated in the mechanisms of damage. The Sertoli cells plays a role of vital importance during the process of spermatogenesis, and it has been identified as one of the principal targets of heavy metals. In the present review, cadmium, lead, and arsenic are broached as altering the physiology of the Sertoli cells, citing mechanisms that have been cited in the literature.
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Affiliation(s)
- Juan Ramos-Treviño
- 1 Department of Reproductive Biology, Biomedical Research Center, Faculty of Medicine, Autonomous University of Coahuila (UAdeC) , Torreón, Coahuila, Mexico
| | - Susana Bassol-Mayagoitia
- 1 Department of Reproductive Biology, Biomedical Research Center, Faculty of Medicine, Autonomous University of Coahuila (UAdeC) , Torreón, Coahuila, Mexico
| | - José Anselmo Hernández-Ibarra
- 1 Department of Reproductive Biology, Biomedical Research Center, Faculty of Medicine, Autonomous University of Coahuila (UAdeC) , Torreón, Coahuila, Mexico
| | - Pablo Ruiz-Flores
- 2 Department of Genetics and Molecular Medicine, Biomedical Research Center, Faculty of Medicine, Autonomous University of Coahuila (UAdeC) , Torreón, Coahuila, Mexico
| | - Martha P Nava-Hernández
- 1 Department of Reproductive Biology, Biomedical Research Center, Faculty of Medicine, Autonomous University of Coahuila (UAdeC) , Torreón, Coahuila, Mexico
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27
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Maya Miles D, Peñate X, Sanmartín Olmo T, Jourquin F, Muñoz Centeno MC, Mendoza M, Simon MN, Chavez S, Geli V. High levels of histones promote whole-genome-duplications and trigger a Swe1 WEE1-dependent phosphorylation of Cdc28 CDK1. eLife 2018; 7:35337. [PMID: 29580382 PMCID: PMC5871333 DOI: 10.7554/elife.35337] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 03/05/2018] [Indexed: 12/13/2022] Open
Abstract
Whole-genome duplications (WGDs) have played a central role in the evolution of genomes and constitute an important source of genome instability in cancer. Here, we show in Saccharomyces cerevisiae that abnormal accumulations of histones are sufficient to induce WGDs. Our results link these WGDs to a reduced incorporation of the histone variant H2A.Z to chromatin. Moreover, we show that high levels of histones promote Swe1WEE1 stabilisation thereby triggering the phosphorylation and inhibition of Cdc28CDK1 through a mechanism different of the canonical DNA damage response. Our results link high levels of histones to a specific type of genome instability that is quite frequently observed in cancer and uncovers a new mechanism that might be able to respond to high levels of histones.
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Affiliation(s)
- Douglas Maya Miles
- Marseille Cancer Research Center (CRCM), U1068 Inserm, UMR7258 CNRS, Aix-Marseille Université, Institut Paoli-Calmettes, Equipe Labellisée Ligue, Marseille, France
| | - Xenia Peñate
- Instituto de Biomedicina de Sevilla, Hospital Virgen del Rocío-CSIC-Universidad de Sevilla, Sevilla, Spain
| | - Trinidad Sanmartín Olmo
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain.,Universitat Pompeu Fabra, Barcelona, Spain
| | - Frederic Jourquin
- Marseille Cancer Research Center (CRCM), U1068 Inserm, UMR7258 CNRS, Aix-Marseille Université, Institut Paoli-Calmettes, Equipe Labellisée Ligue, Marseille, France
| | - Maria Cruz Muñoz Centeno
- Instituto de Biomedicina de Sevilla, Hospital Virgen del Rocío-CSIC-Universidad de Sevilla, Sevilla, Spain
| | - Manuel Mendoza
- Centre for Genomic Regulation, Barcelona Institute of Science and Technology, Barcelona, Spain.,Universitat Pompeu Fabra, Barcelona, Spain
| | - Marie-Noelle Simon
- Marseille Cancer Research Center (CRCM), U1068 Inserm, UMR7258 CNRS, Aix-Marseille Université, Institut Paoli-Calmettes, Equipe Labellisée Ligue, Marseille, France
| | - Sebastian Chavez
- Instituto de Biomedicina de Sevilla, Hospital Virgen del Rocío-CSIC-Universidad de Sevilla, Sevilla, Spain
| | - Vincent Geli
- Marseille Cancer Research Center (CRCM), U1068 Inserm, UMR7258 CNRS, Aix-Marseille Université, Institut Paoli-Calmettes, Equipe Labellisée Ligue, Marseille, France
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28
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Minatel BC, Sage AP, Anderson C, Hubaux R, Marshall EA, Lam WL, Martinez VD. Environmental arsenic exposure: From genetic susceptibility to pathogenesis. ENVIRONMENT INTERNATIONAL 2018; 112:183-197. [PMID: 29275244 DOI: 10.1016/j.envint.2017.12.017] [Citation(s) in RCA: 127] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 11/15/2017] [Accepted: 12/12/2017] [Indexed: 05/21/2023]
Abstract
More than 200 million people in 70 countries are exposed to arsenic through drinking water. Chronic exposure to this metalloid has been associated with the onset of many diseases, including cancer. Epidemiological evidence supports its carcinogenic potential, however, detailed molecular mechanisms remain to be elucidated. Despite the global magnitude of this problem, not all individuals face the same risk. Susceptibility to the toxic effects of arsenic is influenced by alterations in genes involved in arsenic metabolism, as well as biological factors, such as age, gender and nutrition. Moreover, chronic arsenic exposure results in several genotoxic and epigenetic alterations tightly associated with the arsenic biotransformation process, resulting in an increased cancer risk. In this review, we: 1) review the roles of inter-individual DNA-level variations influencing the susceptibility to arsenic-induced carcinogenesis; 2) discuss the contribution of arsenic biotransformation to cancer initiation; 3) provide insights into emerging research areas and the challenges in the field; and 4) compile a resource of publicly available arsenic-related DNA-level variations, transcriptome and methylation data. Understanding the molecular mechanisms of arsenic exposure and its subsequent health effects will support efforts to reduce the worldwide health burden and encourage the development of strategies for managing arsenic-related diseases in the era of personalized medicine.
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Affiliation(s)
- Brenda C Minatel
- Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, British Columbia, Canada
| | - Adam P Sage
- Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, British Columbia, Canada
| | - Christine Anderson
- Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, British Columbia, Canada
| | - Roland Hubaux
- Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, British Columbia, Canada
| | - Erin A Marshall
- Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, British Columbia, Canada
| | - Wan L Lam
- Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, British Columbia, Canada
| | - Victor D Martinez
- Department of Integrative Oncology, British Columbia Cancer Research Centre, Vancouver, British Columbia, Canada.
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29
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Rea M, Gripshover T, Fondufe-Mittendorf Y. Selective inhibition of CTCF binding by iAs directs TET-mediated reprogramming of 5-hydroxymethylation patterns in iAs-transformed cells. Toxicol Appl Pharmacol 2018; 338:124-133. [PMID: 29175454 PMCID: PMC5738917 DOI: 10.1016/j.taap.2017.11.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 11/17/2017] [Accepted: 11/19/2017] [Indexed: 12/22/2022]
Abstract
Methylation at cytosine (5mC) is a fundamental epigenetic DNA modification recently associated with iAs-mediated carcinogenesis. In contrast, the role of 5-hydroxymethylcytosine (5hmC), the oxidation product of 5mC in iAs-mediated carcinogenesis is unknown. Here we assess the hydroxymethylome in iAs-transformed cells, showing that dynamic modulation of hydroxymethylated DNA is associated with specific transcriptional networks. Moreover, this pathologic iAs-mediated carcinogenesis is characterized by a shift toward a higher hydroxymethylation pattern genome-wide. At specific promoters, hydroxymethylation correlated with increased gene expression. Furthermore, this increase in hydroxymethylation occurs concurrently with an upregulation of ten-eleven translocation (TET) enzymes that oxidize 5-methylcytosine (5mC) in DNA. To gain an understanding into how iAs might impact TET expression, we found that iAs inhibits the binding of CTCF at the proximal, weak CTCF binding sites of the TET1 and TET2 gene promoters and enhances CTCF binding at the stronger distal binding site. Further analyses suggest that this distal site acts as an enhancer, thus high CTCF occupancy at the enhancer region of TET1 and TET2 possibly drives their high expression in iAs-transformed cells. These results have major implications in understanding the impact of differential CTCF binding, genome architecture and its consequences in iAs-mediated pathogenesis.
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Affiliation(s)
- Matthew Rea
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | - Tyler Gripshover
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA; Eastern Kentucky University, Richmond, KY 40475, USA
| | - Yvonne Fondufe-Mittendorf
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA.
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30
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Eckstein M, Rea M, Fondufe-Mittendorf YN. Transient and permanent changes in DNA methylation patterns in inorganic arsenic-mediated epithelial-to-mesenchymal transition. Toxicol Appl Pharmacol 2017; 331:6-17. [PMID: 28336213 PMCID: PMC5747965 DOI: 10.1016/j.taap.2017.03.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 03/16/2017] [Indexed: 12/12/2022]
Abstract
Chronic low dose inorganic arsenic exposure causes cells to take on an epithelial-to-mesenchymal phenotype, which is a crucial process in carcinogenesis. Inorganic arsenic is not a mutagen and thus epigenetic alterations have been implicated in this process. Indeed, during the epithelial-to-mesenchymal transition, morphologic changes to cells correlate with changes in chromatin structure and gene expression, ultimately driving this process. However, studies on the effects of inorganic arsenic exposure/withdrawal on the epithelial-to-mesenchymal transition and the impact of epigenetic alterations in this process are limited. In this study we used high-resolution microarray analysis to measure the changes in DNA methylation in cells undergoing inorganic arsenic-induced epithelial-to-mesenchymal transition, and on the reversal of this process, after removal of the inorganic arsenic exposure. We found that cells exposed to chronic, low-dose inorganic arsenic exposure showed 30,530 sites were differentially methylated, and with inorganic arsenic withdrawal several differential methylated sites were reversed, albeit not completely. Furthermore, these changes in DNA methylation mainly correlated with changes in gene expression at most sites tested but not at all. This study suggests that DNA methylation changes on gene expression are not clear-cut and provide a platform to begin to uncover the relationship between DNA methylation and gene expression, specifically within the context of inorganic arsenic treatment.
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Affiliation(s)
- Meredith Eckstein
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | - Matthew Rea
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
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31
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Scanlon SE, Scanlon CD, Hegan DC, Sulkowski PL, Glazer PM. Nickel induces transcriptional down-regulation of DNA repair pathways in tumorigenic and non-tumorigenic lung cells. Carcinogenesis 2017; 38:627-637. [PMID: 28472268 DOI: 10.1093/carcin/bgx038] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 04/22/2017] [Indexed: 11/14/2022] Open
Abstract
The heavy metal nickel is a known carcinogen, and occupational exposure to nickel compounds has been implicated in human lung and nasal cancers. Unlike many other environmental carcinogens, however, nickel does not directly induce DNA mutagenesis, and the mechanism of nickel-related carcinogenesis remains incompletely understood. Cellular nickel exposure leads to signaling pathway activation, transcriptional changes and epigenetic remodeling, processes also impacted by hypoxia, which itself promotes tumor growth without causing direct DNA damage. One of the mechanisms by which hypoxia contributes to tumor growth is the generation of genomic instability via down-regulation of high-fidelity DNA repair pathways. Here, we find that nickel exposure similarly leads to down-regulation of DNA repair proteins involved in homology-dependent DNA double-strand break repair (HDR) and mismatch repair (MMR) in tumorigenic and non-tumorigenic human lung cells. Functionally, nickel induces a defect in HDR capacity, as determined by plasmid-based host cell reactivation assays, persistence of ionizing radiation-induced DNA double-strand breaks and cellular hypersensitivity to ionizing radiation. Mechanistically, we find that nickel, in contrast to the metalloid arsenic, acutely induces transcriptional repression of HDR and MMR genes as part of a global transcriptional pattern similar to that seen with hypoxia. Finally, we find that exposure to low-dose nickel reduces the activity of the MLH1 promoter, but only arsenic leads to long-term MLH1 promoter silencing. Together, our data elucidate novel mechanisms of heavy metal carcinogenesis and contribute to our understanding of the influence of the microenvironment on the regulation of DNA repair pathways.
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Affiliation(s)
- Susan E Scanlon
- Department of Therapeutic Radiology and.,Department of Experimental Pathology, Yale University School of Medicine, New Haven, CT 06520-8040, USA
| | - Christine D Scanlon
- Department of Therapeutic Radiology and.,Department of Chemistry, Miss Porter's School, Farmington, CT 06032, USA and
| | - Denise C Hegan
- Department of Therapeutic Radiology and.,Department of Genetics, Yale University School of Medicine, New Haven, CT 06520-8040, USA
| | - Parker L Sulkowski
- Department of Therapeutic Radiology and.,Department of Genetics, Yale University School of Medicine, New Haven, CT 06520-8040, USA
| | - Peter M Glazer
- Department of Therapeutic Radiology and.,Department of Genetics, Yale University School of Medicine, New Haven, CT 06520-8040, USA
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32
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Chen QY, Costa M. A comprehensive review of metal-induced cellular transformation studies. Toxicol Appl Pharmacol 2017; 331:33-40. [DOI: 10.1016/j.taap.2017.05.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 04/30/2017] [Accepted: 05/05/2017] [Indexed: 01/07/2023]
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33
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Eckstein M, Rea M, Fondufe-Mittendorf YN. Microarray dataset of transient and permanent DNA methylation changes in HeLa cells undergoing inorganic arsenic-mediated epithelial-to-mesenchymal transition. Data Brief 2017; 13:6-9. [PMID: 28589171 PMCID: PMC5443927 DOI: 10.1016/j.dib.2017.05.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 04/04/2017] [Accepted: 05/03/2017] [Indexed: 11/25/2022] Open
Abstract
The novel dataset presented here represents the results of the changing pattern of DNA methylation profiles in HeLa cells exposed to chronic low dose (0.5 µM) sodium arsenite, resulting in epithelial-to-mesenchymal transition, as well as DNA methylation patterns in cells where inorganic arsenic has been removed. Inorganic arsenic is a known carcinogen, though not mutagenic. Several mechanisms have been proposed as to how inorganic arsenic drives carcinogenesis such as regulation of the cell׳s redox potential and/or epigenetics. In fact, there are gene specific studies and limited genome-wide studies that have implicated epigenetic factors such as DNA methylation in inorganic arsenic-mediated epithelial-to-mesenchymal transition (EMT). However, genome-wide studies about the impact of 1) chronic, low-dose inorganic arsenic exposure on DNA methylation patterns during inorganic arsenic-induced epithelial-to-mesenchymal transition, and 2) the removal inorganic arsenic (reversal) on DNA methylation patterns, is lacking. For this dataset, two replicates were performed with each of the samples - non-treated, inorganic arsenic-treated, and reverse-treated cells. We provide normalized and processed data, and log2 fold change in DNA methylation. The raw microarray data are available through NCBI GEO, accession number GSE95232 and a related research paper has been accepted for published in Toxicology and Applied Pharmacology (Eckstein et al., 2017) [1].
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34
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Eckstein M, Eleazer R, Rea M, Fondufe-Mittendorf Y. Epigenomic reprogramming in inorganic arsenic-mediated gene expression patterns during carcinogenesis. REVIEWS ON ENVIRONMENTAL HEALTH 2017; 32:93-103. [PMID: 27701139 DOI: 10.1515/reveh-2016-0025] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 08/08/2016] [Indexed: 05/22/2023]
Abstract
Arsenic is a ubiquitous metalloid that is not mutagenic but is carcinogenic. The mechanism(s) by which arsenic causes cancer remain unknown. To date, several mechanisms have been proposed, including the arsenic-induced generation of reactive oxygen species (ROS). However, it is also becoming evident that inorganic arsenic (iAs) may exert its carcinogenic effects by changing the epigenome, and thereby modifying chromatin structure and dynamics. These epigenetic changes alter the accessibility of gene regulatory factors to DNA, resulting in specific changes in gene expression both at the levels of transcription initiation and gene splicing. In this review, we discuss recent literature reports describing epigenetic changes induced by iAs exposure and the possible epigenetic mechanisms underlying these changes.
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35
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Holcomb N, Goswami M, Han SG, Scott T, D'Orazio J, Orren DK, Gairola CG, Mellon I. Inorganic arsenic inhibits the nucleotide excision repair pathway and reduces the expression of XPC. DNA Repair (Amst) 2017; 52:70-80. [PMID: 28237621 DOI: 10.1016/j.dnarep.2017.02.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 01/11/2017] [Accepted: 02/12/2017] [Indexed: 11/17/2022]
Abstract
Chronic exposure to arsenic, most often through contaminated drinking water, has been linked to several types of cancer in humans, including skin and lung cancer. However, the mechanisms underlying its role in causing cancer are not well understood. There is evidence that exposure to arsenic can enhance the carcinogenicity of UV light in inducing skin cancers and may enhance the carcinogenicity of tobacco smoke in inducing lung cancers. The nucleotide excision repair (NER) pathway removes different types of DNA damage including those produced by UV light and components of tobacco smoke. The aim of the present study was to investigate the effect of sodium arsenite on the NER pathway in human lung fibroblasts (IMR-90 cells) and primary mouse keratinocytes. To measure NER, we employed a slot-blot assay to quantify the introduction and removal of UV light-induced 6-4 photoproducts (6-4 PP) and cyclobutane pyrimidine dimers (CPDs). We find a concentration-dependent inhibition of the removal of 6-4 PPs and CPDs in both cell types treated with arsenite. Treatment of both cell types with arsenite resulted in a significant reduction in the abundance of XPC, a protein that is critical for DNA damage recognition in NER. The abundance of RNA expressed from several key NER genes was also significantly reduced by treatment of IMR-90 cells with arsenite. Finally, treatment of IMR-90 cells with MG-132 abrogated the reduction in XPC protein, suggesting an involvement of the proteasome in the reduction of XPC protein produced by treatment of cells with arsenic. The inhibition of NER by arsenic may reflect one mechanism underlying the role of arsenic exposure in enhancing cigarette smoke-induced lung carcinogenesis and UV light-induced skin cancer, and it may provide some insights into the emergence of arsenic trioxide as a chemotherapeutic agent.
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Affiliation(s)
- Nathaniel Holcomb
- Department of Toxicology and Cancer Biology, The Markey Cancer Center, University of Kentucky, Lexington, KY, United States
| | - Mamta Goswami
- Department of Toxicology and Cancer Biology, The Markey Cancer Center, University of Kentucky, Lexington, KY, United States
| | - Sung Gu Han
- Toxicology Laboratory, Department of Food Science and Biotechnology of Animal Resources, College of Animal Bioscience and Technology, Konkuk University, Seoul 05029, Republic of Korea
| | - Tim Scott
- Department of Toxicology and Cancer Biology, The Markey Cancer Center, University of Kentucky, Lexington, KY, United States
| | - John D'Orazio
- Department of Toxicology and Cancer Biology, The Markey Cancer Center, University of Kentucky, Lexington, KY, United States
| | - David K Orren
- Department of Toxicology and Cancer Biology, The Markey Cancer Center, University of Kentucky, Lexington, KY, United States
| | - C Gary Gairola
- Department of Toxicology and Cancer Biology, The Markey Cancer Center, University of Kentucky, Lexington, KY, United States
| | - Isabel Mellon
- Department of Toxicology and Cancer Biology, The Markey Cancer Center, University of Kentucky, Lexington, KY, United States.
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36
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Rea M, Eckstein M, Eleazer R, Smith C, Fondufe-Mittendorf YN. Genome-wide DNA methylation reprogramming in response to inorganic arsenic links inhibition of CTCF binding, DNMT expression and cellular transformation. Sci Rep 2017; 7:41474. [PMID: 28150704 PMCID: PMC5288714 DOI: 10.1038/srep41474] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 12/20/2016] [Indexed: 12/31/2022] Open
Abstract
Chronic low dose inorganic arsenic (iAs) exposure leads to changes in gene expression and epithelial-to-mesenchymal transformation. During this transformation, cells adopt a fibroblast-like phenotype accompanied by profound gene expression changes. While many mechanisms have been implicated in this transformation, studies that focus on the role of epigenetic alterations in this process are just emerging. DNA methylation controls gene expression in physiologic and pathologic states. Several studies show alterations in DNA methylation patterns in iAs-mediated pathogenesis, but these studies focused on single genes. We present a comprehensive genome-wide DNA methylation analysis using methyl-sequencing to measure changes between normal and iAs-transformed cells. Additionally, these differential methylation changes correlated positively with changes in gene expression and alternative splicing. Interestingly, most of these differentially methylated genes function in cell adhesion and communication pathways. To gain insight into how genomic DNA methylation patterns are regulated during iAs-mediated carcinogenesis, we show that iAs probably targets CTCF binding at the promoter of DNA methyltransferases, regulating their expression. These findings reveal how CTCF binding regulates DNA methyltransferase to reprogram the methylome in response to an environmental toxin.
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Affiliation(s)
- Matthew Rea
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | - Meredith Eckstein
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | - Rebekah Eleazer
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | - Caroline Smith
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA.,Bellarmine University, Louisville, KY 40205, USA
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37
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Kobayashi T. Understanding the biology of urothelial cancer metastasis. Asian J Urol 2016; 3:211-222. [PMID: 29264189 PMCID: PMC5730871 DOI: 10.1016/j.ajur.2016.09.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2016] [Revised: 09/02/2016] [Accepted: 09/08/2016] [Indexed: 12/29/2022] Open
Abstract
Management of unresectable urothelial cancer (UC) has been a clinical challenge for decades. While drug resistance is a key issue, precise understanding of biology of UC metastasis is another challenge for the improvement of treatment outcome of UC patients. Introduction of the cell biology concepts including epithelial-mesenchymal transition (EMT) and cancer stemness seems to explain UC metastasis. Molecular genetics based on gene expression profiling, next generation sequencing, and explosion of non-coding RNA world has opened the door to intrinsic molecular subtyping of UC. Next steps include, based on the recently accumulated understanding, the establishment of novel disease models representing UC metastasis in various experimental platforms, particularly in vivo animal systems. Indeed, novel knowledge molecular genetics has not been fully linked to the modeling of UC metastasis. Further understanding of bladder carcinogenesis is needed particularly with regard to cell of origin related to tumor characteristics including driver gene alterations, pathological differentiations, and metastatic ability. Then we will be able to establish better disease models, which will consequently lead us to further understanding of biology and eventually the development of novel therapeutic strategies for UC metastasis.
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38
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Abstract
DNA methylation alterations are common in urothelial carcinoma, a prevalent cancer worldwide caused predominantly by chemical carcinogens. Recent studies have proposed sets of hypermethylated genes as promising diagnostic and prognostic biomarkers from urine or tissue samples, which require validation. Other studies have revealed intriguing links between specific carcinogens and DNA methylation alterations in cancer tissues or blood that might clarify carcinogenesis mechanisms and aid prevention. Like DNA methylation alterations, mutations in chromatin regulators are frequent, underlining the importance of epigenetic changes. However, the relations between the two changes and their functions in urothelial carcinogenesis remain unclear. Transcription factor genes with altered methylation deserve particular interest. Elucidating the functional impact of methylation changes is a prerequisite for their therapeutic targeting.
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Affiliation(s)
- Wolfgang A Schulz
- Department of Urology, Medical Faculty, Heinrich Heine University Duesseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Wolfgang Goering
- Department of Pathology, Medical Faculty, Heinrich Heine University Duesseldorf, Germany
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39
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Ganapathy S, Li P, Fagman J, Yu T, Lafontant J, Zhang G, Chen C. Low doses of arsenic, via perturbing p53, promotes tumorigenesis. Toxicol Appl Pharmacol 2016; 306:98-104. [DOI: 10.1016/j.taap.2016.07.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 07/12/2016] [Accepted: 07/13/2016] [Indexed: 11/27/2022]
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40
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Rea M, Jiang T, Eleazer R, Eckstein M, Marshall AG, Fondufe-Mittendorf YN. Quantitative Mass Spectrometry Reveals Changes in Histone H2B Variants as Cells Undergo Inorganic Arsenic-Mediated Cellular Transformation. Mol Cell Proteomics 2016; 15:2411-22. [PMID: 27169413 PMCID: PMC4937513 DOI: 10.1074/mcp.m116.058412] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 05/09/2016] [Indexed: 11/06/2022] Open
Abstract
Exposure to inorganic arsenic, a ubiquitous environmental toxic metalloid, leads to carcinogenesis. However, the mechanism is unknown. Several studies have shown that inorganic arsenic exposure alters specific gene expression patterns, possibly through alterations in chromatin structure. While most studies on understanding the mechanism of chromatin-mediated gene regulation have focused on histone post-translational modifications, the role of histone variants remains largely unknown. Incorporation of histone variants alters the functional properties of chromatin. To understand the global dynamics of chromatin structure and function in arsenic-mediated carcinogenesis, analysis of the histone variants incorporated into the nucleosome and their covalent modifications is required. Here we report the first global mass spectrometric analysis of histone H2B variants as cells undergo arsenic-mediated epithelial to mesenchymal transition. We used electron capture dissociation-based top-down tandem mass spectrometry analysis validated with quantitative reverse transcription real-time polymerase chain reaction to identify changes in the expression levels of H2B variants in inorganic arsenic-mediated epithelial-mesenchymal transition. We identified changes in the expression levels of specific histone H2B variants in two cell types, which are dependent on dose and length of exposure of inorganic arsenic. In particular, we found increases in H2B variants H2B1H/1K/1C/1J/1O and H2B2E/2F, and significant decreases in H2B1N/1D/1B as cells undergo inorganic arsenic-mediated epithelial-mesenchymal transition. The analysis of these histone variants provides a first step toward an understanding of the functional significance of the diversity of histone structures, especially in inorganic arsenic-mediated gene expression and carcinogenesis.
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Affiliation(s)
- Matthew Rea
- From the ‡Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky 40536
| | - Tingting Jiang
- §Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306
| | - Rebekah Eleazer
- From the ‡Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky 40536
| | - Meredith Eckstein
- From the ‡Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky 40536
| | - Alan G Marshall
- §Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306; ¶Ion Cyclotron Resonance Program, National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310
| | - Yvonne N Fondufe-Mittendorf
- From the ‡Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky 40536;
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McCoy CR, Stadelman BS, Brumaghim JL, Liu JT, Bain LJ. Arsenic and Its Methylated Metabolites Inhibit the Differentiation of Neural Plate Border Specifier Cells. Chem Res Toxicol 2015; 28:1409-21. [PMID: 26024302 DOI: 10.1021/acs.chemrestox.5b00036] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Exposure to arsenic in food and drinking water has been correlated with adverse developmental outcomes, such as reductions in birth weight and neurological deficits. Additionally, studies have shown that arsenic suppresses sensory neuron formation and skeletal muscle myogenesis, although the reason why arsenic targets both of these cell types in unclear. Thus, P19 mouse embryonic stem cells were used to investigate the mechanisms by which arsenic could inhibit cellular differentiation. P19 cells were exposed to 0, 0.1, or 0.5 μM sodium arsenite and induced to form embryoid bodies over a period of 5 days. The expression of transcription factors necessary to form neural plate border specifier (NPBS) cells, neural crest cells and their progenitors, and myocytes and their progenitors were examined. Early during differentiation, arsenic significantly reduced the transcript and protein expression of Msx1 and Pax3, both needed for NPBS cell formation. Arsenic also significantly reduced the protein expression of Sox 10, needed for neural crest progenitor cell production, by 31-50%, and downregulated the protein and mRNA levels of NeuroD1, needed for neural crest cell differentiation, in a time- and dose-dependent manner. While the overall protein expression of transcription factors in the skeletal muscle lineage was not changed, arsenic did alter their nuclear localization. MyoD nuclear translocation was significantly reduced on days 2-5 between 15 and 70%. At a 10-fold lower concentration, monomethylarsonous acid (MMA III) appeared to be just as potent as inorganic arsenic at reducing the mRNA levels Pax3 (79% vs84%), Sox10 (49% vs 65%), and Msx1 (56% vs 56%). Dimethylarsinous acid (DMA III) also reduced protein and transcript expression, but the changes were less dramatic than those with MMA or arsenite. All three arsenic species reduced the nuclear localization of MyoD and NeuroD1 in a similar manner. The early changes in the differentiation of neural plate border specifier cells may provide a mechanism for arsenic to suppress both neurogenesis and myogenesis.
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Affiliation(s)
- Christopher R McCoy
- †Department of Biological Sciences, Clemson University, 132 Long Hall, Clemson, South Carolina 29634, United States
| | - Bradley S Stadelman
- ‡Department of Chemistry, Clemson University, 219 Hunter Laboratories, Clemson, South Carolina 29634, United States
| | - Julia L Brumaghim
- ‡Department of Chemistry, Clemson University, 219 Hunter Laboratories, Clemson, South Carolina 29634, United States
| | - Jui-Tung Liu
- §Environmental Toxicology Graduate Program, Clemson University, 132 Long Hall, Clemson, South Carolina 29634, United States
| | - Lisa J Bain
- †Department of Biological Sciences, Clemson University, 132 Long Hall, Clemson, South Carolina 29634, United States.,§Environmental Toxicology Graduate Program, Clemson University, 132 Long Hall, Clemson, South Carolina 29634, United States
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