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Fischer F, Stößer S, Wegmann L, Veh E, Lumpp T, Parsdorfer M, Schumacher P, Hartwig A. Chromate Affects Gene Expression and DNA Methylation in Long-Term In Vitro Experiments in A549 Cells. Int J Mol Sci 2024; 25:10129. [PMID: 39337613 PMCID: PMC11431867 DOI: 10.3390/ijms251810129] [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: 08/14/2024] [Revised: 09/14/2024] [Accepted: 09/17/2024] [Indexed: 09/30/2024] Open
Abstract
Chromate has been shown to dysregulate epigenetic mechanisms such as DNA methylation, leading to changes in gene expression and genomic instability. However, most in vitro studies are limited to short incubation periods, although chronic exposure may be more relevant for both environmental and occupational exposure. In this study, human adenocarcinoma A549 cells were treated with 1, 2 or 5 µM chromate for 24 h and compared with incubations with 0.2, 0.5 or 1 µM chromate for 1 to 5 weeks. Chromium accumulated in a pronounced time- and concentration-dependent manner after short-term treatment, whereas a plateau of intracellular chromium content was observed after long-term treatment. While short-term treatment induced a G2 arrest of the cell cycle, this effect was not observed after long-term treatment at lower concentrations. The opposite was observed for global DNA methylation: while short-term treatment showed no effect of chromate, significant dose-dependent hypomethylation was observed in the long-term experiments. Time-dependent effects were also observed in a high-throughput RT-qPCR gene expression analysis, particularly in genes related to the inflammatory response and DNA damage response. Taken together, the results suggest specific differences in toxicity profiles when comparing short-term and long-term exposure to chromate in A549 cells.
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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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2
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Islam S, Sarkar O, Mukherjee S, Kamila S, Bhowmik AD, Chattopadhyay A. Chronic low-dose chromium VI exposure induces oxidative stress and apoptosis with altered expressions of DNA repair genes and promoter hypermethylation in the liver of Swiss albino mice. J Appl Toxicol 2024; 44:1014-1027. [PMID: 38523572 DOI: 10.1002/jat.4600] [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: 02/06/2024] [Revised: 02/23/2024] [Accepted: 03/04/2024] [Indexed: 03/26/2024]
Abstract
The present investigation dealt with harmful effects of hexavalent chromium (Cr [VI]) on liver of Swiss albino mice. This variant exhibited cytotoxicity, mutagenicity, and carcinogenicity. Our study focused on elucidating the hepatotoxic effects of chronic low-dose exposure to Cr (VI) (2, 5, and 10 ppm) administered via drinking water for 4 and 8 months. The observed elevation in SGPT, ALP, and SGOT and increased oxidative stress markers unequivocally confirmed the severe disruption of liver homeostasis at these low treatment doses. Noteworthy alterations in histoarchitecture, body weight, and water intake provided further evidences of the harmful effects of Cr (VI). Production of reactive oxygen species (ROS) during metabolism led to DNA damages. Immunohistochemistry and qRT-PCR analyses revealed that chronic low-dose exposure of Cr (VI) induced apoptosis in liver tissue. Our study exhibited alterations in the expression pattern of DNA repair genes (Rad51, Mutyh, Mlh1, and Ogg1), coupled with promoter hypermethylation of Mutyh and Rad51, leading to transcriptional inhibition. Our findings underscored the potential of low-dose Cr (VI) exposure on hepatotoxicity by the intricate interplay between apoptosis induction and epigenetic alterations of DNA repair genes.
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Affiliation(s)
- Shehnaz Islam
- Department of Zoology, Visva-Bharati, Santiniketan, West Bengal, India
| | - Olivia Sarkar
- Department of Zoology, Visva-Bharati, Santiniketan, West Bengal, India
| | - Sunanda Mukherjee
- Department of Zoology, Visva-Bharati, Santiniketan, West Bengal, India
| | - Sreejata Kamila
- Department of Zoology, Visva-Bharati, Santiniketan, West Bengal, India
| | - Arpan Dey Bhowmik
- Department of Zoology, Visva-Bharati, Santiniketan, West Bengal, India
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3
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Wang PS, Liu Z, Sweef O, Saeed AF, Kluz T, Costa M, Shroyer KR, Kondo K, Wang Z, Yang C. Hexavalent chromium exposure activates the non-canonical nuclear factor kappa B pathway to promote immune checkpoint protein programmed death-ligand 1 expression and lung carcinogenesis. Cancer Lett 2024; 589:216827. [PMID: 38527692 PMCID: PMC11375691 DOI: 10.1016/j.canlet.2024.216827] [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: 12/12/2023] [Revised: 03/07/2024] [Accepted: 03/20/2024] [Indexed: 03/27/2024]
Abstract
Lung cancer is the leading cause of cancer-related death worldwide; however, the mechanism of lung carcinogenesis has not been clearly defined. Chronic exposure to hexavalent chromium [Cr(VI)], a common environmental and occupational pollutant, causes lung cancer, representing an important lung cancer etiology factor. The mechanism of how chronic Cr(VI) exposure causes lung cancer remains largely unknown. By using cell culture and mouse models and bioinformatics analyses of human lung cancer gene expression profiles, this study investigated the mechanism of Cr(VI)-induced lung carcinogenesis. A new mouse model of Cr(VI)-induced lung carcinogenesis was developed as evidenced by the findings showing that a 16-week Cr(VI) exposure (CaCrO4, 100 μg per mouse once per week) via oropharyngeal aspiration induced lung adenocarcinomas in male and female A/J mice, whereas none of the sham-exposed control mice had lung tumors. Mechanistic studies revealed that chronic Cr(VI) exposure activated the non-canonical NFκB pathway through the long non-coding RNA (lncRNA) ABHD11-AS1/deubiquitinase USP15-mediated tumor necrosis factor receptor-associated factor 3 (TRAF3) down-regulation. The non-canonical NFκB pathway activation increased the interleukin 6 (IL-6)/Janus kinase (Jak)/signal transducer and activator of transcription 3 (Stat3) signaling. The activation of the IL-6/Jak signaling axis by Cr(VI) exposure not only promoted inflammation but also stabilized the immune checkpoint molecule programmed death-ligand 1 (PD-L1) protein in the lungs, reducing T lymphocyte infiltration to the lungs. Given the well-recognized critical role of PD-L1 in inhibiting anti-tumor immunity, these findings suggested that the lncRNA ABHD11-AS1-mediated non-canonical NFκB pathway activation and PD-L1 up-regulation may play important roles in Cr(VI)-induced lung carcinogenesis.
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Affiliation(s)
- Po-Shun Wang
- Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY, USA
| | - Zulong Liu
- Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY, USA
| | - Osama Sweef
- Division of Cancer Biology, Department of Medicine, MetroHealth Medical Center, Case Western Reserve University School of Medicine, Cleveland, OH, USA
| | - Abdullah Farhan Saeed
- Division of Cancer Biology, Department of Medicine, MetroHealth Medical Center, Case Western Reserve University School of Medicine, Cleveland, OH, USA
| | - Thomas Kluz
- Department of Environment Medicine, New York University School of Medicine, New York, NY, USA
| | - Max Costa
- Department of Environment Medicine, New York University School of Medicine, New York, NY, USA
| | - Kenneth R Shroyer
- Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY, USA; Department of Pathology, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY, USA
| | - Kazuya Kondo
- Department of Oncological Medical Services, Graduate School of Biomedical Sciences, Tokushima University Graduate School, Tokushima City, 770-8509, Japan
| | - Zhishan Wang
- Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY, USA; Department of Pathology, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY, USA
| | - Chengfeng Yang
- Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY, USA; Department of Pathology, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY, USA.
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4
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Wang Z, Liu Z, Wang PS, Lin HP, Rea M, Kondo K, Yang C. Epigenetic downregulation of O 6-methylguanine-DNA methyltransferase contributes to chronic hexavalent chromium exposure-caused genotoxic effect and cell transformation. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 341:122978. [PMID: 37995958 PMCID: PMC11372728 DOI: 10.1016/j.envpol.2023.122978] [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: 06/25/2023] [Revised: 10/07/2023] [Accepted: 11/15/2023] [Indexed: 11/25/2023]
Abstract
Hexavalent chromium [Cr(VI)] is a common environmental pollutant and chronic exposure to Cr(VI) causes lung cancer and other types of cancer in humans, although the mechanism of Cr(VI) carcinogenesis remains elusive. Cr(VI) has been considered as a genotoxic carcinogen, but accumulating evidence indicates that Cr(VI) also causes various epigenetic toxic effects that play important roles in Cr(VI) carcinogenesis. However, it is not clear how Cr(VI)-caused epigenetic dysregulations contributes to Cr(VI) carcinogenesis. This study investigates whether Cr(VI) epigenetic toxic effect has an impact on its genotoxic effect. It was found that chronic low dose of Cr(VI) exposure time-dependently down-regulates the expression of a critical DNA damage repair protein O6-methylguanine-DNA methyltransferase (MGMT), leading to the increases of the levels of the highly mutagenic and carcinogenic DNA lesion O6-methylguanine (O6-MeG) in human bronchial epithelial BEAS-2B cells. Moreover, the levels of MGMT and O6-MeG in chronic Cr(VI) exposure-caused human lung cancer tissues are also significantly lower and higher than that in the adjacent normal lung tissues, respectively. It was further determined that chronic low dose of Cr(VI) exposure-transformed BEAS-2B cells display impaired DNA damage repair capacity and a high sensitivity to the toxicity of the alkylating chemotherapeutic drug Temozolomide. In contrast, stably overexpressing MGMT in parental BEAS-2B cells reverses chronic low dose of Cr(VI) exposure-caused DNA damage repair deficiency and significantly reduces cell transformation by Cr(VI). Further mechanistical studies revealed that chronic low dose of Cr(VI) exposure down-regulates MGMT expression through epigenetic mechanisms by increasing DNA methylation and histone H3 repressive modifications. Taken together, these findings suggest that epigenetic down-regulation of a crucial DNA damage repair protein MGMT contributes significantly to the genotoxic effect and cell transformation caused by chronic low dose of Cr(VI) exposure.
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Affiliation(s)
- Zhishan Wang
- Stony Brook Cancer Center, Stony Brook University, Lauterbur Drive, Stony Brook, NY 11794, USA; Department of Pathology, Renaissance School of Medicine, Stony Brook University, 101 Nicolls Road, Stony Brook, NY 11794, USA.
| | - Zulong Liu
- Stony Brook Cancer Center, Stony Brook University, Lauterbur Drive, Stony Brook, NY 11794, USA
| | - Po-Shun Wang
- Stony Brook Cancer Center, Stony Brook University, Lauterbur Drive, Stony Brook, NY 11794, USA
| | - Hsuan-Pei Lin
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY 40536, USA
| | - Matthew Rea
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40536, USA
| | - Kazuya Kondo
- Department of Oncological Medical Services, Graduate School of Biomedical Sciences, Tokushima University Graduate School, Tokushima City 770-8509, Japan
| | - Chengfeng Yang
- Stony Brook Cancer Center, Stony Brook University, Lauterbur Drive, Stony Brook, NY 11794, USA; Department of Pathology, Renaissance School of Medicine, Stony Brook University, 101 Nicolls Road, Stony Brook, NY 11794, USA
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5
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Toyoda JH, Martino J, Speer RM, Meaza I, Lu H, Williams AR, Bolt AM, Kouokam JC, Aboueissa AEM, Wise JP. Hexavalent Chromium Targets Securin to Drive Numerical Chromosome Instability in Human Lung Cells. Int J Mol Sci 2023; 25:256. [PMID: 38203427 PMCID: PMC10778806 DOI: 10.3390/ijms25010256] [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: 11/18/2023] [Revised: 12/14/2023] [Accepted: 12/15/2023] [Indexed: 01/12/2024] Open
Abstract
Hexavalent chromium [Cr(VI)] is a known human lung carcinogen with widespread exposure in environmental and occupational settings. Despite well-known cancer risks, the molecular mechanisms of Cr(VI)-induced carcinogenesis are not well understood, but a major driver of Cr(VI) carcinogenesis is chromosome instability. Previously, we reported Cr(VI) induced numerical chromosome instability, premature centriole disengagement, centrosome amplification, premature centromere division, and spindle assembly checkpoint bypass. A key regulator of these events is securin, which acts by regulating the cleavage ability of separase. Thus, in this study we investigated securin disruption by Cr(VI) exposure. We exposed human lung cells to a particulate Cr(VI) compound, zinc chromate, for acute (24 h) and prolonged (120 h) time points. We found prolonged Cr(VI) exposure caused marked decrease in securin levels and function. After prolonged exposure at the highest concentration, securin protein levels were decreased to 15.3% of control cells, while securin mRNA quantification was 7.9% relative to control cells. Additionally, loss of securin function led to increased separase activity manifested as enhanced cleavage of separase substrates; separase, kendrin, and SCC1. These data show securin is targeted by prolonged Cr(VI) exposure in human lung cells. Thus, a new mechanistic model for Cr(VI)-induced carcinogenesis emerges with centrosome and centromere disruption as key components of numerical chromosome instability, a key driver in Cr(VI) carcinogenesis.
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Affiliation(s)
- Jennifer H. Toyoda
- Wise Laboratory for Environmental and Genetic Toxicology, University of Louisville, 500 S Preston Street, Building 55A, Room 1422, Louisville, KY 40292, USA (R.M.S.); (H.L.); (J.C.K.)
| | - Julieta Martino
- Wise Laboratory for Environmental and Genetic Toxicology, University of Louisville, 500 S Preston Street, Building 55A, Room 1422, Louisville, KY 40292, USA (R.M.S.); (H.L.); (J.C.K.)
| | - Rachel M. Speer
- Wise Laboratory for Environmental and Genetic Toxicology, University of Louisville, 500 S Preston Street, Building 55A, Room 1422, Louisville, KY 40292, USA (R.M.S.); (H.L.); (J.C.K.)
| | - Idoia Meaza
- Wise Laboratory for Environmental and Genetic Toxicology, University of Louisville, 500 S Preston Street, Building 55A, Room 1422, Louisville, KY 40292, USA (R.M.S.); (H.L.); (J.C.K.)
| | - Haiyan Lu
- Wise Laboratory for Environmental and Genetic Toxicology, University of Louisville, 500 S Preston Street, Building 55A, Room 1422, Louisville, KY 40292, USA (R.M.S.); (H.L.); (J.C.K.)
| | - Aggie R. Williams
- Wise Laboratory for Environmental and Genetic Toxicology, University of Louisville, 500 S Preston Street, Building 55A, Room 1422, Louisville, KY 40292, USA (R.M.S.); (H.L.); (J.C.K.)
| | - Alicia M. Bolt
- Department of Pharmaceutical Sciences, The University of New Mexico College of Pharmacy, Albuquerque, NM 87131, USA;
| | - Joseph Calvin Kouokam
- Wise Laboratory for Environmental and Genetic Toxicology, University of Louisville, 500 S Preston Street, Building 55A, Room 1422, Louisville, KY 40292, USA (R.M.S.); (H.L.); (J.C.K.)
| | | | - John Pierce Wise
- Wise Laboratory for Environmental and Genetic Toxicology, University of Louisville, 500 S Preston Street, Building 55A, Room 1422, Louisville, KY 40292, USA (R.M.S.); (H.L.); (J.C.K.)
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6
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Liu J, Huang B, Ding F, Li Y. Environment factors, DNA methylation, and cancer. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2023; 45:7543-7568. [PMID: 37715840 DOI: 10.1007/s10653-023-01749-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 08/30/2023] [Indexed: 09/18/2023]
Abstract
Today, the rapid development of science and technology and the rapid change in economy and society are changing the way of life of human beings and affecting the natural, living, working, and internal environment on which human beings depend. At the same time, the global incidence of cancer has increased significantly yearly, and cancer has become the number one killer that threatens human health. Studies have shown that diet, living habits, residential environment, mental and psychological factors, intestinal flora, genetics, social factors, and viral and non-viral infections are closely related to human cancer. However, the molecular mechanisms of the environment and cancer development remain to be further explored. In recent years, DNA methylation has become a key hub and bridge for environmental and cancer research. Some environmental factors can alter the hyper/hypomethylation of human cancer suppressor gene promoters, proto-oncogene promoters, and the whole genome, causing low/high expression or gene mutation of related genes, thereby exerting oncogenic or anticancer effects. It is expected to develop early warning markers of cancer environment based on DNA methylation, thereby providing new methods for early detection of cancers, diagnosis, and targeted therapy. This review systematically expounds on the internal mechanism of environmental factors affecting cancer by changing DNA methylation, aiming to help establish the concept of cancer prevention and improve people's health.
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Affiliation(s)
- Jie Liu
- Department of General Surgery, Second Hospital of Lanzhou University, Lan Zhou, China
- Key Laboratory of the Digestive System Tumors of Gansu Province, Second Hospital of Lanzhou University, Lan Zhou, China
| | - Binjie Huang
- Department of General Surgery, Second Hospital of Lanzhou University, Lan Zhou, China
- Key Laboratory of the Digestive System Tumors of Gansu Province, Second Hospital of Lanzhou University, Lan Zhou, China
| | - Feifei Ding
- Department of General Surgery, Second Hospital of Lanzhou University, Lan Zhou, China
- Key Laboratory of the Digestive System Tumors of Gansu Province, Second Hospital of Lanzhou University, Lan Zhou, China
| | - Yumin Li
- Department of General Surgery, Second Hospital of Lanzhou University, Lan Zhou, China.
- Key Laboratory of the Digestive System Tumors of Gansu Province, Second Hospital of Lanzhou University, Lan Zhou, China.
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7
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Murthy MK, Khandayataray P, Padhiary S, Samal D. A review on chromium health hazards and molecular mechanism of chromium bioremediation. REVIEWS ON ENVIRONMENTAL HEALTH 2023; 38:461-478. [PMID: 35537040 DOI: 10.1515/reveh-2021-0139] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 04/19/2022] [Indexed: 05/13/2023]
Abstract
Living beings have been devastated by environmental pollution, which has reached its peak. The disastrous pollution of the environment is in large part due to industrial wastes containing toxic pollutants. The widespread use of chromium (Cr (III)/Cr (VI)) in industries, especially tanneries, makes it one of the most dangerous environmental pollutants. Chromium pollution is widespread due to ineffective treatment methods. Bioremediation of chromium (Cr) using bacteria is very thoughtful due to its eco-friendly and cost-effective outcome. In order to counter chromium toxicity, bacteria have numerous mechanisms, such as the ability to absorb, reduce, efflux, or accumulate the metal. In this review article, we focused on chromium toxicity on human and environmental health as well as its bioremediation mechanism.
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Affiliation(s)
| | | | - Samprit Padhiary
- Department of Biotechnology, Academy of Management and Information Technology, Khordha, India
| | - Dibyaranjan Samal
- Department of Biotechnology, Academy of Management and Information Technology, Khordha, India
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8
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Liang Y, Wang H, Wu B, Peng N, Yu D, Wu X, Zhong X. The emerging role of N 6-methyladenine RNA methylation in metal ion metabolism and metal-induced carcinogenesis. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023:121897. [PMID: 37244530 DOI: 10.1016/j.envpol.2023.121897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 05/23/2023] [Accepted: 05/24/2023] [Indexed: 05/29/2023]
Abstract
N6-methyladenine (m6A) is the most common and abundant internal modification in eukaryotic mRNAs, which can regulate gene expression and perform important biological tasks. Metal ions participate in nucleotide biosynthesis and repair, signal transduction, energy generation, immune defense, and other important metabolic processes. However, long-term environmental and occupational exposure to metals through food, air, soil, water, and industry can result in toxicity, serious health problems, and cancer. Recent evidence indicates dynamic and reversible m6A modification modulates various metal ion metabolism, such as iron absorption, calcium uptake and transport. In turn, environmental heavy metal can alter m6A modification by directly affecting catalytic activity and expression level of methyltransferases and demethylases, or through reactive oxygen species, eventually disrupting normal biological function and leading to diseases. Therefore, m6A RNA methylation may play a bridging role in heavy metal pollution-induced carcinogenesis. This review discusses interaction among heavy metal, m6A, and metal ions metabolism, and their regulatory mechanism, focuses on the role of m6A methylation and heavy metal pollution in cancer. Finally, the role of nutritional therapy that targeting m6A methylation to prevent metal ion metabolism disorder-induced cancer is summarized.
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Affiliation(s)
- Yaxu Liang
- Joint International Research Laboratory of Animal Health & Food Safety, College of Animal Science and Technology, Nanjing Agricultural University, No.1 Weigang, Nanjing, 210095, China
| | - Huan Wang
- Joint International Research Laboratory of Animal Health & Food Safety, College of Animal Science and Technology, Nanjing Agricultural University, No.1 Weigang, Nanjing, 210095, China
| | - Bencheng Wu
- Anyou Biotechnology Group Co., LTD., Taicang, 215437, China
| | - Ning Peng
- Joint International Research Laboratory of Animal Health & Food Safety, College of Animal Science and Technology, Nanjing Agricultural University, No.1 Weigang, Nanjing, 210095, China
| | - Dongming Yu
- Joint International Research Laboratory of Animal Health & Food Safety, College of Animal Science and Technology, Nanjing Agricultural University, No.1 Weigang, Nanjing, 210095, China
| | - Xin Wu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Xiang Zhong
- Joint International Research Laboratory of Animal Health & Food Safety, College of Animal Science and Technology, Nanjing Agricultural University, No.1 Weigang, Nanjing, 210095, China.
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9
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Zhang Q, Feng H, Hu G, Zheng P, Su Z, Zhang Y, Hong S, Xu J, Wang T, Jia G. Hexavalent chromium induces γH2AX and RAD51 involved in DNA damage repair in BEAS-2B cells by modulating LNC-DHFR-4:1. ENVIRONMENT INTERNATIONAL 2023; 174:107895. [PMID: 36966638 DOI: 10.1016/j.envint.2023.107895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 03/16/2023] [Accepted: 03/19/2023] [Indexed: 06/18/2023]
Abstract
Hexavalent chromium [Cr(VI)] is rarely found in nature. Its occurrence in the environment is mainly due to anthropogenic sources. Our previous studies have shown that Cr(VI) exposure could change the expression profile of long noncoding RNAs (lncRNAs). However, the relationship between lncRNAs and genetic damage induced by Cr(VI) remains unclear. In this study, RT-qPCR was used to verify the expression of genes and lncRNAs involved in DNA damage repair in BEAS-2B cells exposed to different Cr(VI) concentrations. After screening out LNC-DHFR-4:1, overexpression and knockdown models of BEAS-2B cells were used to further identify the relationship between the lncRNA and RAD51. RT-qPCR and indirect immunofluorescence were used to detect expression. Our results revealed that with increasing Cr(VI) concentration, γH2AX expression was increased, while the expression of RAD51 was decreased. Meanwhile, LNC-DHFR-4:1 acted as a competitive endogenous RNA to regulate the expression of γH2AX and RAD51, which further affected DNA damage repair. The overexpression of LNC-DHFR-4:1 induced a twofold decrease in γH2AX and a onefold increase in RAD51, and its knockdown showed the opposite results. These results suggested that LNC-DHFR-4:1 might be a potential biomarker of Cr(VI)-induced DNA damage repair in BEAS-2B cells.
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Affiliation(s)
- Qiaojian Zhang
- Department of Occupational and Environmental Health Science, School of Public Health, Peking University, Beijing, China
| | - Huimin Feng
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Guiping Hu
- School of Engineering Medicine, Beihang University, Beijing, China, Key Laboratory of Biomechanics and Mechanobiology (Beihang University), Ministry of Education, China
| | - Pai Zheng
- Department of Occupational and Environmental Health Science, School of Public Health, Peking University, Beijing, China
| | - Zekang Su
- Department of Occupational and Environmental Health Science, School of Public Health, Peking University, Beijing, China
| | - Yali Zhang
- Department of Occupational and Environmental Health Science, School of Public Health, Peking University, Beijing, China
| | - Shiyi Hong
- Department of Occupational and Environmental Health Science, School of Public Health, Peking University, Beijing, China
| | - Jiayu Xu
- Department of Occupational and Environmental Health Science, School of Public Health, Peking University, Beijing, China
| | - Tiancheng Wang
- Department of Clinical Laboratory, Third Hospital of Peking University, Beijing, China.
| | - Guang Jia
- Department of Occupational and Environmental Health Science, School of Public Health, Peking University, Beijing, China.
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10
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Islam S, Kamila S, Chattopadhyay A. Toxic and carcinogenic effects of hexavalent chromium in mammalian cells in vivo and in vitro: a recent update. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART C, TOXICOLOGY AND CARCINOGENESIS 2023; 40:282-315. [PMID: 36728911 DOI: 10.1080/26896583.2022.2158675] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Chromium VI (Cr (VI)) can cross cell membranes readily and causes the formation of Cr-DNA adducts, genomic damages, elevation of reactive oxygen species (ROS) and alteration of survival signaling pathways, as evidenced by the modulation in p53 signaling pathway. Mammals, including humans are exposed to Cr, including Cr (VI), frequently through inhalation, drinking water, and food. Several studies demonstrated that Cr (VI) induces cellular death through apoptosis and autophagy, genotoxicity, functional alteration of mitochondria, endocrine and reproductive impairments. In the present review, studies on deleterious effects of Cr (VI) exposure to mammalian cells (in vivo and in vitro) have been documented. Special attention is paid to the underlying molecular mechanism of Cr (VI) toxicity.
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Affiliation(s)
- Shehnaz Islam
- Department of Zoology, Visva-Bharati, Santiniketan, West Bengal, India
| | - Sreejata Kamila
- Department of Zoology, Visva-Bharati, Santiniketan, West Bengal, India
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11
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Zhao L, Islam R, Wang Y, Zhang X, Liu LZ. Epigenetic Regulation in Chromium-, Nickel- and Cadmium-Induced Carcinogenesis. Cancers (Basel) 2022; 14:cancers14235768. [PMID: 36497250 PMCID: PMC9737485 DOI: 10.3390/cancers14235768] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 11/17/2022] [Accepted: 11/18/2022] [Indexed: 11/25/2022] Open
Abstract
Environmental and occupational exposure to heavy metals, such as hexavalent chromium, nickel, and cadmium, are major health concerns worldwide. Some heavy metals are well-documented human carcinogens. Multiple mechanisms, including DNA damage, dysregulated gene expression, and aberrant cancer-related signaling, have been shown to contribute to metal-induced carcinogenesis. However, the molecular mechanisms accounting for heavy metal-induced carcinogenesis and angiogenesis are still not fully understood. In recent years, an increasing number of studies have indicated that in addition to genotoxicity and genetic mutations, epigenetic mechanisms play critical roles in metal-induced cancers. Epigenetics refers to the reversible modification of genomes without changing DNA sequences; epigenetic modifications generally involve DNA methylation, histone modification, chromatin remodeling, and non-coding RNAs. Epigenetic regulation is essential for maintaining normal gene expression patterns; the disruption of epigenetic modifications may lead to altered cellular function and even malignant transformation. Therefore, aberrant epigenetic modifications are widely involved in metal-induced cancer formation, development, and angiogenesis. Notably, the role of epigenetic mechanisms in heavy metal-induced carcinogenesis and angiogenesis remains largely unknown, and further studies are urgently required. In this review, we highlight the current advances in understanding the roles of epigenetic mechanisms in heavy metal-induced carcinogenesis, cancer progression, and angiogenesis.
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12
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Wang Z, Yang C. Epigenetic and epitranscriptomic mechanisms of chromium carcinogenesis. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2022; 96:241-265. [PMID: 36858774 PMCID: PMC10565670 DOI: 10.1016/bs.apha.2022.07.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Hexavalent chromium [Cr(VI)], a Group I carcinogen classified by the International Agency for Research on Cancer (IARC), represents one of the most common occupational and environmental pollutants. The findings from human epidemiological and laboratory animal studies show that long-term exposure to Cr(VI) causes lung cancer and other cancer. Although Cr(VI) is a well-recognized carcinogen, the mechanism of Cr(VI) carcinogenesis has not been well understood. Due to the fact that Cr(VI) undergoes a series of metabolic reductions once entering cells to generate reactive Cr metabolites and reactive oxygen species (ROS) causing genotoxicity, Cr(VI) is generally considered as a genotoxic carcinogen. However, more and more studies have demonstrated that acute or chronic Cr(VI) exposure also causes epigenetic dysregulations including changing DNA methylation, histone posttranslational modifications and regulatory non-coding RNA (microRNA and long non-coding RNA) expressions. Moreover, emerging evidence shows that Cr(VI) exposure is also capable of altering cellular epitranscriptome. Given the increasingly recognized importance of epigenetic and epitranscriptomic dysregulations in cancer initiation and progression, it is believed that Cr(VI) exposure-caused epigenetic and epitranscriptomic changes could play important roles in Cr(VI) carcinogenesis. The goal of this chapter is to review the epigenetic and epitranscriptomic effects of Cr(VI) exposure and discuss their roles in Cr(VI) carcinogenesis. Better understanding the mechanism of Cr(VI) carcinogenesis may identify new molecular targets for more efficient prevention and treatment of cancer resulting from Cr(VI) exposure.
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Affiliation(s)
- Zhishan Wang
- Division of Cancer Biology, Department of Medicine, MetroHealth Medical Center, Case Western Reserve University School of Medicine, Cleveland, OH, United States
| | - Chengfeng Yang
- Division of Cancer Biology, Department of Medicine, MetroHealth Medical Center, Case Western Reserve University School of Medicine, Cleveland, OH, United States.
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13
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Qie Y, Zhou D, Wu Z, Liu S, Shen C, Hu H, Zhang C, Xu Y. Low-dose hexavalent chromium(VI) exposure promotes prostate cancer cell proliferation by activating MAGEB2-AR signal pathway. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 241:113724. [PMID: 35660381 DOI: 10.1016/j.ecoenv.2022.113724] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 05/15/2022] [Accepted: 05/29/2022] [Indexed: 06/15/2023]
Abstract
Hexavalent chromium [Cr(VI)], one common environmental contaminant, has long been recognized as a carcinogen associated with several malignancies, such as lung cancer, but little information was available about the effects of its low-dose environmental exposure in prostate cancer. Our previous study has shown that low-dose Cr(VI) exposure could promote prostate cancer(PCa) cell growth in vitro and in vivo. In the present study, we furthermore found that low-dose Cr(VI) exposure could induce DNA demethylation in PCa cells. Based on our transcriptome sequencing data and DNA methylation database, we further identified MAGEB2 as a potential effector target that contributed to tumor-promoting effect of low-dose Cr(VI) exposure in PCa. In addition, we demonstrated that MAGEB2 was upregulated in PCa and its knockdown restrained PCa cell proliferation and tumor growth in vitro and in vivo. Moreover, Co-IP and point mutation experiments confirmed that MAGEB2 could bind to the NH2-terminal NTD domain of AR through the F-box in the MAGE homology domain, and then activated AR through up-regulating its downstream targets PSA and NX3.1. Together, low-dose Cr(VI) exposure can induce DNA demethylation in prostate cancer cells, and promote cell proliferation via activating MAGEB2-AR signaling pathway. Thus, inhibition of MAGEB2-AR signaling is a novel and promising strategy to reverse low-dose Cr(VI) exposure-induced prostate tumor progression, also as effective adjuvant therapy for AR signaling-dependent PCa.
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Affiliation(s)
- Yunkai Qie
- Department of Urology, Tianjin Institute of Urology, The Second Hospital of Tianjin Medical University, Tianjin 300211, China; CAS Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
| | - Diansheng Zhou
- Department of Urology, Tianjin Institute of Urology, The Second Hospital of Tianjin Medical University, Tianjin 300211, China
| | - Zhouliang Wu
- Department of Urology, Tianjin Institute of Urology, The Second Hospital of Tianjin Medical University, Tianjin 300211, China
| | - Shenglai Liu
- Department of Urology, Tianjin Institute of Urology, The Second Hospital of Tianjin Medical University, Tianjin 300211, China
| | - Chong Shen
- Department of Urology, Tianjin Institute of Urology, The Second Hospital of Tianjin Medical University, Tianjin 300211, China
| | - Hailong Hu
- Department of Urology, Tianjin Institute of Urology, The Second Hospital of Tianjin Medical University, Tianjin 300211, China
| | - Changwen Zhang
- Department of Urology, Tianjin Institute of Urology, The Second Hospital of Tianjin Medical University, Tianjin 300211, China.
| | - Yong Xu
- Department of Urology, Tianjin Institute of Urology, The Second Hospital of Tianjin Medical University, Tianjin 300211, China.
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14
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Mechanism of chromium-induced toxicity in lungs, liver, and kidney and their ameliorative agents. Biomed Pharmacother 2022; 151:113119. [PMID: 35613529 DOI: 10.1016/j.biopha.2022.113119] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 05/05/2022] [Accepted: 05/10/2022] [Indexed: 11/21/2022] Open
Abstract
Heavy metal Chromium (Cr), can adversely affect humans and their health if accumulated in organs of the body, such as the lungs, liver, and kidneys. Cr (VI) is highly toxic and has a higher solubility in water than Cr (III). One of the most common routes for Cr exposure is through inhalation and is associated with liver, lung, kidney damage, widespread dermatitis, GI tract damage, human lung cancer, cardiomyopathies, and cardiovascular disease. The increase in ROS production has been attributed to most of the damage caused by Cr toxicity. Cr-induced ROS-mediated oxidative stress has been seen to cause a redox imbalance affecting the antioxidant system balance in the body. The Nrf2 pathway dysregulation has been implicated in the same. Deregulation of histone acetylation and methylation has been observed, together with gene methylation in genes such as p16, MGMT, APC, hMLH1, and also miR-143 repression. Several ultra-structural changes have been observed following Cr (VI)-toxicity, including rough ER dilation, alteration in the mitochondrial membrane and nuclear membrane, pycnotic nuclei formation, and cytoplasm vacuolization. A significant change was observed in the metabolism of lipid, glucose, and the metabolism of protein after exposure to Cr. Cr-toxicity also leads to immune system dysregulations with changes seen in the expression of IL-8, IL-4, IgM, lymphocytes, and leukocytes among others. P53, as well as pro-and anti-apoptotic proteins, are involved in apoptosis. These Cr-induced damages can be alleviated via agents that restore antioxidant balance, regulate Nrf-2 levels, or increase anti-apoptotic proteins while decreasing pro-apoptotic proteins.
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15
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Wang Z, Uddin MB, Xie J, Tao H, Zeidler-Erdely PC, Kondo K, Yang C. Chronic Hexavalent Chromium Exposure Upregulates the RNA Methyltransferase METTL3 Expression to Promote Cell Transformation, Cancer Stem Cell-Like Property, and Tumorigenesis. Toxicol Sci 2022; 187:51-61. [PMID: 35201342 PMCID: PMC9216043 DOI: 10.1093/toxsci/kfac023] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Hexavalent chromium [Cr(VI)] is a common environmental carcinogen causing lung cancer in humans. This study investigates the mechanism of Cr(VI) carcinogenesis focusing on the role of the epitranscriptomic dysregulation. The epitranscriptomic effect of Cr(VI) was determined in Cr(VI)-transformed human bronchial epithelial cells, chromate-exposed mouse and human lungs. The epitranscriptomic effect and its role in Cr(VI)-induced cell transformation, cancer stem cell (CSC)-like property, and tumorigenesis were determined by microarray analysis, soft agar colony formation, suspension spheroid formation, and mouse xenograft tumorigenesis assays. It was found that chronic Cr(VI) exposure causes epitranscriptomic dysregulations as evidenced by the increased levels of total RNA N6-methyladenosine (m6A) modification and the RNA m6A methyltransferase like-3 (METTL3) in Cr(VI)-transformed cells and chromate exposure-caused mouse and human lung tumors. Knockdown of METTL3 expression in Cr(VI)-transformed cells significantly reduces their m6A levels and transformed phenotypes and tumorigenicity in mice. Moreover, knockdown of METTL3 expression in parental nontransformed cells significantly reduces the capability of chronic Cr(VI) exposure to induce cell transformation and CSC-like property. Together, this study reveals that chronic Cr(VI) exposure is capable of altering cellular epitranscriptome by increasing the m6A RNA modification via upregulating the RNA methyltransferase METTL3 expression, which plays an important role in Cr(VI)-induced cell transformation, CSC-like property, and tumorigenesis.
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Affiliation(s)
- Zhishan Wang
- Division of Cancer Biology, Department of Medicine, MetroHealth Medical Center, Case Western Reserve University School of Medicine, Cleveland, Ohio 44109, USA
| | - Mohammad Burhan Uddin
- Center for Environmental and Systems Biochemistry, University of Kentucky College of Medicine, Lexington, Kentucky 40536, USA
| | - Jie Xie
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, Kentucky 40536, USA
| | - Hua Tao
- Division of Cancer Biology, Department of Medicine, MetroHealth Medical Center, Case Western Reserve University School of Medicine, Cleveland, Ohio 44109, USA
| | - Patti C Zeidler-Erdely
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, West Virginia 26508, USA
| | - Kazuya Kondo
- Department of Oncological Medical Services, Graduate School of Biomedical Sciences, Tokushima University Graduate School, Tokushima City 770-8509, Japan
| | - Chengfeng Yang
- Division of Cancer Biology, Department of Medicine, MetroHealth Medical Center, Case Western Reserve University School of Medicine, Cleveland, Ohio 44109, USA
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16
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Tuminello S, Zhang Y, Yang L, Durmus N, Snuderl M, Heguy A, Zeleniuch-Jacquotte A, Chen Y, Shao Y, Reibman J, Arslan AA. Global DNA Methylation Profiles in Peripheral Blood of WTC-Exposed Community Members with Breast Cancer. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19095104. [PMID: 35564499 PMCID: PMC9105091 DOI: 10.3390/ijerph19095104] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Revised: 04/16/2022] [Accepted: 04/19/2022] [Indexed: 12/22/2022]
Abstract
Breast cancer represents the most common cancer diagnosis among World Trade Center (WTC)-exposed community members, residents, and cleanup workers enrolled in the WTC Environmental Health Center (WTC EHC). The primary aims of this study were (1) to compare blood DNA methylation profiles of WTC-exposed community members with breast cancer and WTC-unexposed pre-diagnostic breast cancer blood samples, and (2) to compare the DNA methylation differences among the WTC EHC breast cancer cases and WTC-exposed cancer-free controls. Gene pathway enrichment analyses were further conducted. There were significant differences in DNA methylation between WTC-exposed breast cancer cases and unexposed prediagnostic breast cancer cases. The top differentially methylated genes were Intraflagellar Transport 74 (IFT74), WD repeat-containing protein 90 (WDR90), and Oncomodulin (OCM), which are commonly upregulated in tumors. Probes associated with established tumor suppressor genes (ATM, BRCA1, PALB2, and TP53) were hypermethylated among WTC-exposed breast cancer cases compared to the unexposed group. When comparing WTC EHC breast cancer cases vs. cancer-free controls, there appeared to be global hypomethylation among WTC-exposed breast cancer cases compared to exposed controls. Functional pathway analysis revealed enrichment of several gene pathways in WTC-exposed breast cancer cases including endocytosis, proteoglycans in cancer, regulation of actin cytoskeleton, axon guidance, focal adhesion, calcium signaling, cGMP-PKG signaling, mTOR, Hippo, and oxytocin signaling. The results suggest potential epigenetic links between WTC exposure and breast cancer in local community members enrolled in the WTC EHC program.
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Affiliation(s)
- Stephanie Tuminello
- Department of Population Health, New York University Langone Health, New York, NY 10016, USA; (Y.Z.); (A.Z.-J.); (Y.C.); (Y.S.)
- Correspondence: (S.T.); (A.A.A.)
| | - Yian Zhang
- Department of Population Health, New York University Langone Health, New York, NY 10016, USA; (Y.Z.); (A.Z.-J.); (Y.C.); (Y.S.)
| | - Lei Yang
- Foundation Medicine, Cambridge, MA 02141, USA;
| | - Nedim Durmus
- Department of Medicine, New York University Langone Health, New York, NY 10016, USA; (N.D.); (J.R.)
| | - Matija Snuderl
- Department of Pathology, New York University Langone Health, New York, NY 10016, USA; (M.S.); (A.H.)
| | - Adriana Heguy
- Department of Pathology, New York University Langone Health, New York, NY 10016, USA; (M.S.); (A.H.)
- NYU Langone’s Genome Technology Center, New York, NY 10016, USA
| | - Anne Zeleniuch-Jacquotte
- Department of Population Health, New York University Langone Health, New York, NY 10016, USA; (Y.Z.); (A.Z.-J.); (Y.C.); (Y.S.)
- NYU Perlmutter Comprehensive Cancer Center, New York, NY 10016, USA
| | - Yu Chen
- Department of Population Health, New York University Langone Health, New York, NY 10016, USA; (Y.Z.); (A.Z.-J.); (Y.C.); (Y.S.)
- NYU Perlmutter Comprehensive Cancer Center, New York, NY 10016, USA
| | - Yongzhao Shao
- Department of Population Health, New York University Langone Health, New York, NY 10016, USA; (Y.Z.); (A.Z.-J.); (Y.C.); (Y.S.)
- NYU Perlmutter Comprehensive Cancer Center, New York, NY 10016, USA
| | - Joan Reibman
- Department of Medicine, New York University Langone Health, New York, NY 10016, USA; (N.D.); (J.R.)
| | - Alan A. Arslan
- Department of Population Health, New York University Langone Health, New York, NY 10016, USA; (Y.Z.); (A.Z.-J.); (Y.C.); (Y.S.)
- NYU Perlmutter Comprehensive Cancer Center, New York, NY 10016, USA
- Department of Obstetrics and Gynecology, New York University Langone Health, New York, NY 10016, USA
- Correspondence: (S.T.); (A.A.A.)
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17
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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: 12] [Impact Index Per Article: 6.0] [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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18
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Xia B, Yuan J, Pang L, He K. Chromium [Cr(VI)] Exposure Causes Cytotoxicity of Human Bronchial Epithelial Cells (16-HBE) and Proteomic Alterations. Int J Toxicol 2022; 41:225-233. [PMID: 35341331 DOI: 10.1177/10915818221078277] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Hexavalent chromium [Cr(VI)] is a common industrial pollutant, and exposure may cause toxic effects in multiple organ systems and carcinogenesis, including lung cancer. However, the toxic effect of Cr(VI) on the respiratory system is poorly understood. In the present study, it was demonstrated that Cr(VI) exposure significantly decreased the viability of human bronchial epithelial cells (16-HBE) in a dose-dependent manner. Flow cytometry demonstrated that Cr(VI) enhanced the transition of 16-HBE cells from G1 to S phase and arrested S-phase progression. Reverse transcription-quantitative polymerase chain reaction analysis revealed a significant alteration in the expression of apoptosis-associated genes in Cr(VI)-treated 16-HBE cells. In addition, using two-dimensional fluorescence differential gel electrophoresis with mass spectrometry, 15 differentially expressed proteins (1 upregulated and 14 downregulated) were identified in 16-HBE cells with Cr(VI) treatment compared with controls. Functional classification revealed that these differentially expressed proteins were involved in apoptosis, cytoskeletal structure, and energy metabolism. In conclusion, these data suggested that Cr(VI) caused toxic effects in bronchial epithelial cells and the mechanisms may involve the abnormal expression of apoptosis-associated proteins, cytoskeletal proteins, and energy metabolism-associated proteins.
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Affiliation(s)
- Bo Xia
- College of Food Science and Technology, 12575Hunan Agricultural University, East Renmin Road, Changsha, China.,Key Laboratory of Modern Toxicology of Shenzhen, 568734Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Jiao Yuan
- College of Food Science and Technology, 12575Hunan Agricultural University, East Renmin Road, Changsha, China
| | - Li Pang
- College of Horticulture, 12575Hunan Agricultural University, East Renmin Road, Changsha, China
| | - Kaiwu He
- Key Laboratory of Modern Toxicology of Shenzhen, 568734Shenzhen Center for Disease Control and Prevention, Shenzhen, China
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19
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Gohar J, Do WL, Miller-Kleinhenz J, Conneely K, Krishnamurti U, D'Angelo O, Gogineni K, Torres M, Gabram-Mendola S, McCullough LE. Neighborhood characteristics and breast tumor methylation: using epigenomics to explore cancer outcome disparities. Breast Cancer Res Treat 2022; 191:653-663. [PMID: 34978015 DOI: 10.1007/s10549-021-06430-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 10/15/2021] [Indexed: 02/06/2023]
Abstract
BACKGROUND Social exposures may drive epigenetic alterations that affect racial disparities in breast cancer outcomes. This study examined the association between neighborhood-level factors and DNA methylation in non-Hispanic Black and White women diagnosed with breast cancer. METHODS Genome-wide DNA methylation was measured using the EPIC array in the tumor tissue of 96 women. Linear regression models were used to examine the association between nine neighborhood-level factors and methylation, regressing β values for each cytosine-phosphate guanine dinucleotide (CpG) site on neighborhood-level factors while adjusting for covariates. Neighborhood data were obtained from the Opportunity Atlas. We used a false discovery rate (FDR) threshold < 0.05, and for CpGs below this threshold, we examined interactions with race. We employed multivariable Cox proportional-hazards models to estimate whether aberrant methylation was associated with all-cause mortality. RESULTS 26 of the CpG sites were associated with job density or college education (FDR < 0.05). Further exploration of these 26 CpG sites revealed no interactions by race, but a single probe in TMEM204 was associated with all-cause mortality. CONCLUSION We identified novel associations between neighborhood-level factors and the breast tumor DNA methylome. Our data are the first to show that dysregulation in neighborhood associated CpG sites may be associated with all-cause mortality. Neighborhood-level factors may contribute to differential tumor methylation in genes related to tumor progression and metastasis. This contributes to the increasing body of evidence that area-level factors (such as neighborhood characteristics) may play an important role in cancer disparities through modulation of the breast tumor epigenome.
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Affiliation(s)
- Jazib Gohar
- Department of Epidemiology, Emory University Rollins School of Public Health, Atlanta, GA, 30322, USA
| | - Whitney L Do
- Department of Global Health, Emory University Rollins School of Public Health, Atlanta, GA, 30322, USA
| | - Jasmine Miller-Kleinhenz
- Department of Epidemiology, Emory University Rollins School of Public Health, Atlanta, GA, 30322, USA
| | - Karen Conneely
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Uma Krishnamurti
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Olivia D'Angelo
- Department of Surgery, Jackson Memorial Hospital/University of Miami Miller School of Medicine, Miami, FL, 33136, USA
| | - Keerthi Gogineni
- Department of Medical Oncology, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Mylin Torres
- Department of Radiation Oncology, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | | | - Lauren E McCullough
- Department of Epidemiology, Emory University Rollins School of Public Health, Atlanta, GA, 30322, USA.
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20
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Ha F, Li N, Long C, Zheng P, Hu G, Jia G, Wang T. The Effect of Global DNA Methylation on PDCD5 Expression in the PBMC of Occupational Chromate Exposed Workers. J Occup Environ Med 2021; 63:600-608. [PMID: 34184653 DOI: 10.1097/jom.0000000000002192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To evaluate the alteration of protein of programmed cell death 5 (PDCD5) in peripheral blood mononuclear cells (PBMC) and DNA methylation caused by hexavalent chromium exposure. METHODS There were 112 workers and 56 controls in this study. The chromium in RBC and urine, PBMC with PDCD5+, DNA methylation, urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and score of DNA damage were measured. RESULTS In chromate exposed workers, the percent of PBMC with PDCD5+, urine 8-OHdG, and score of DNA damage were significantly higher, whereas global DNA methylation was significantly lower. The binary logistic regression and generalized linear mixed model analysis showed that the percent of PBMC with PDCD5+ was significantly associated with global DNA hypomethylation. CONCLUSIONS The aberrant DNA hypomethylation plays an important role in PBMC apoptosis of occupational hexavalent chromium exposure.
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Affiliation(s)
- Feizai Ha
- Department of Laboratory Medicine, Peking University Third Hospital, Beijing, China (Ms Ha, Ms Li, and Dr Wang); Department of Occupational and Environmental Health, School of Public Health, Peking University, Beijing, China (Dr Long, Dr Zheng, Dr Hu, and Dr Jia)
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21
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Li P, Zhang X, Murphy AJ, Costa M, Zhao X, Sun H. Downregulation of hedgehog-interacting protein (HHIP) contributes to hexavalent chromium-induced malignant transformation of human bronchial epithelial cells. Carcinogenesis 2021; 42:136-147. [PMID: 32710611 DOI: 10.1093/carcin/bgaa085] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 07/10/2020] [Accepted: 07/20/2020] [Indexed: 12/25/2022] Open
Abstract
Hexavalent chromium [Cr(VI)] is a potent human lung carcinogen. Multiple mechanisms have been proposed that contribute to Cr(VI)-induced lung carcinogenesis including oxidative stress, DNA damage, genomic instability and epigenetic modulation. However, the molecular mechanisms and pathways mediating Cr(VI) carcinogenicity have not been fully elucidated. Hedgehog (Hh) signaling is a key pathway that plays important roles in the formation of multiple tissues during embryogenesis and in the maintenance of stem cell populations in adults. Dysregulation of Hh signaling pathway has been reported in many human cancers. Here, we report a drastic reduction in both mRNA and protein levels of hedgehog-interacting protein (HHIP), a downstream target and a negative regulator of Hh signaling, in Cr(VI)-transformed cells. These findings point to a potential role of Hh signaling in Cr(VI)-induced malignant transformation and lung carcinogenesis. Cr(VI)-transformed cells exhibited DNA hypermethylation and silencing histone marks in the promoter region of HHIP, indicating that an epigenetic mechanism mediates Cr(VI)-induced silencing of HHIP. In addition, the major targets of Hh signaling (GLI1-3 and PTCH1) were significantly increased in Cr(VI)-transformed cells, suggesting an aberrant activation of Hh signaling in these cells. Moreover, ectopically expressing HHIP not only suppressed Hh signaling but also inhibited cell proliferation and anchorage-independent growth in Cr(VI)-transformed cells. In conclusion, these findings establish a novel regulatory mechanism underlying Cr(VI)-induced lung carcinogenesis and provide new insights for developing a better diagnostic and prognostic strategy for Cr(VI)-related human lung cancer.
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Affiliation(s)
- Peichao Li
- Department of Thoracic Surgery, The Second Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China.,Department of Environmental Medicine, NYU School of Medicine, New York
| | - Xiaoru Zhang
- Department of Environmental Medicine, NYU School of Medicine, New York
| | - Anthony J Murphy
- Department of Environmental Medicine, NYU School of Medicine, New York
| | - Max Costa
- Department of Environmental Medicine, NYU School of Medicine, New York
| | - Xiaogang Zhao
- Department of Thoracic Surgery, The Second Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Hong Sun
- Department of Environmental Medicine, NYU School of Medicine, New York
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22
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Zhang Y, Zheng P, Su Z, Hu G, Jia G. Perspectives of Genetic Damage and Epigenetic Alterations by Hexavalent Chromium: Time Evolution Based on a Bibliometric Analysis. Chem Res Toxicol 2021; 34:684-694. [PMID: 33663212 DOI: 10.1021/acs.chemrestox.0c00415] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Compounds containing hexavalent chromium [Cr(VI)] have been classified as Group I human carcinogens in 1990 by the International Agency for Research on Cancer, known to induce human lung cancers. To determine the nature of Cr(VI) carcinogenesis, much has been learned about genetic damage and epigenetic alterations. On the basis of bibliometric analysis of the available literature found between 1966 and 2020, the present study investigated the evolution of author keywords; provided a summary of relevant studies focused on populations, animals/plants, or cells; and depicted the co-operation among countries or institutions and research group development. Additionally, multiomics technology and bioinformatics analysis can be a valuable tool for figuring out new biomarkers from different molecular levels like gene, RNA, protein, and metabolite and ascertaining the mechanism pathways of Cr(VI) genotoxicity and carcinogenesis.
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Affiliation(s)
- Yali Zhang
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing 100191, China
| | - Pai Zheng
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing 100191, China
| | - Zekang Su
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing 100191, China
| | - Guiping Hu
- School of Medical Science and Engineering, Beihang University, Beijing 100191, China.,Beijing Advanced Innovation Center for Big Data-Based Precision Medicine, Beihang University, Beijing 100191, China.,Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, Beijing, 100191, China
| | - Guang Jia
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing 100191, China
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23
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Ghosh A, Mukherjee S, Roy M, Datta A. Modulatory role of tea in arsenic induced epigenetic alterations in carcinogenesis. THE NUCLEUS 2021. [DOI: 10.1007/s13237-020-00346-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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24
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Zhu Y, Costa M. Metals and molecular carcinogenesis. Carcinogenesis 2020; 41:1161-1172. [PMID: 32674145 PMCID: PMC7513952 DOI: 10.1093/carcin/bgaa076] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 06/19/2020] [Accepted: 07/13/2020] [Indexed: 12/11/2022] Open
Abstract
Many metals are essential for living organisms, but at higher doses they may be toxic and carcinogenic. Metal exposure occurs mainly in occupational settings and environmental contaminations in drinking water, air pollution and foods, which can result in serious health problems such as cancer. Arsenic (As), beryllium (Be), cadmium (Cd), chromium (Cr) and nickel (Ni) are classified as Group 1 carcinogens by the International Agency for Research on Cancer. This review provides a comprehensive summary of current concepts of the molecular mechanisms of metal-induced carcinogenesis and focusing on a variety of pathways, including genotoxicity, mutagenesis, oxidative stress, epigenetic modifications such as DNA methylation, histone post-translational modification and alteration in microRNA regulation, competition with essential metal ions and cancer-related signaling pathways. This review takes a broader perspective and aims to assist in guiding future research with respect to the prevention and therapy of metal exposure in human diseases including cancer.
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Affiliation(s)
- Yusha Zhu
- Department of Environmental Medicine, New York University Grossman School of Medicine, New York, NY, USA
| | - Max Costa
- Department of Environmental Medicine, New York University Grossman School of Medicine, New York, NY, USA
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25
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Pavesi T, Moreira JC. Mechanisms and individuality in chromium toxicity in humans. J Appl Toxicol 2020; 40:1183-1197. [DOI: 10.1002/jat.3965] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 02/10/2020] [Accepted: 02/23/2020] [Indexed: 12/18/2022]
Affiliation(s)
- Thelma Pavesi
- Centro de Estudos da Saúde do Trabalhador e Ecologia HumanaEscola Nacional de Saúde Pública, Fundação Oswaldo Cruz Rio de Janeiro Brazil
| | - Josino Costa Moreira
- Centro de Estudos da Saúde do Trabalhador e Ecologia HumanaEscola Nacional de Saúde Pública, Fundação Oswaldo Cruz Rio de Janeiro Brazil
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26
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Feng L, Guo X, Li T, Yao C, Xia H, Jiang Z, Jia J, Fang Y, Shi L, Lu CA, Lou J. Novel DNA methylation biomarkers for hexavalent chromium exposure: an epigenome-wide analysis. Epigenomics 2020; 12:221-233. [DOI: 10.2217/epi-2019-0216] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Aim: We aimed to identify differential methylation of genes that could illuminate the biological mechanisms of chromium (VI) toxicity in this exposure-control study. Materials & methods: DNA methylation was measured in blood samples collected from electroplating workers and controls using a combination of Infinium Methylation450K Chip and targeted-bisulfite sequencing. QuantiGene assay was used to detect the mRNA expression of differentially methylated genes. Inductively coupled plasma–mass spectrometry was used to quantify metals in blood and urine samples. The cytosine–phosphate–guanine sites methylation and gene expression were confirmed in a human lymphoblastoid cell line. Results & conclusion: A total of 131 differentially methylated cytosine–phosphate–guanine sites were found between exposures and controls. DNA methylation of SEMA4B may serve as a potential biomarker for chromium (VI) exposure.
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Affiliation(s)
- Lingfang Feng
- Institute of Occupational Diseases, Zhejiang Academy of Medical Sciences, Hangzhou 310013, PR China
| | - Xinnian Guo
- Institute of Occupational Diseases, Zhejiang Academy of Medical Sciences, Hangzhou 310013, PR China
| | - Tao Li
- Institute of Occupational Diseases, Zhejiang Academy of Medical Sciences, Hangzhou 310013, PR China
| | - Chunji Yao
- Institute of Hygiene, Zhejiang Academy of Medical Sciences, Hangzhou 310013, PR China
| | - Hailing Xia
- Institute of Occupational Diseases, Zhejiang Academy of Medical Sciences, Hangzhou 310013, PR China
| | - Zhaoqiang Jiang
- Institute of Occupational Diseases, Zhejiang Academy of Medical Sciences, Hangzhou 310013, PR China
| | - Junlin Jia
- Center for Biostatistics, Bioinformatics & Big Data, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou 310009, PR China
| | - Yuan Fang
- Institute of Occupational Diseases, Zhejiang Academy of Medical Sciences, Hangzhou 310013, PR China
| | - Li Shi
- Institute of Occupational Diseases, Zhejiang Academy of Medical Sciences, Hangzhou 310013, PR China
| | - Chensheng Alex Lu
- Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Jianlin Lou
- Institute of Occupational Diseases, Zhejiang Academy of Medical Sciences, Hangzhou 310013, PR China
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27
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Wang Z, Lin HP, Li Y, Tao H, Yang P, Xie J, Maddy D, Kondo K, Yang C. Chronic Hexavalent Chromium Exposure Induces Cancer Stem Cell-Like Property and Tumorigenesis by Increasing c-Myc Expression. Toxicol Sci 2019; 172:252-264. [PMID: 31504995 PMCID: PMC6876261 DOI: 10.1093/toxsci/kfz196] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Hexavalent chromium [Cr(VI)] is one of the most common environmental carcinogen causing lung cancer in humans; however, the mechanism of Cr(VI) carcinogenesis remains elusive. Cancer stem cells (CSCs) are considered as cancer initiating and maintaining cells. Ours and other recent studies showed that chronic Cr(VI) exposure induces CSC-like property representing an important mechanism of Cr(VI) carcinogenesis. However, how Cr(VI) exposure induces CSC-like property remains largely unknown. In this study, we found that stably knocking down the expression of c-Myc, a proto-oncogene and one of key stemness factors playing critical roles in cancer initiation and progression, in Cr(VI)-transformed human bronchial epithelial cells [BEAS-2B-Cr(VI)] significantly decreased their CSC-like property and tumorigenicity in mice. Moreover, stably knocking down c-Myc expression in parental nontransformed BEAS-2B cells significantly impaired the capability of chronic Cr(VI) exposure to induce CSC-like property and cell transformation. It was also found that stably overexpressing c-Myc alone in parental nontransformed BEAS-2B cells is capable of causing CSC-like property and cell transformation. Mechanistic studies showed that chronic Cr(VI) exposure increases c-Myc expression by down-regulating the level of microRNA-494 (miR-494). It was further determined that overexpressing miR-494 significantly reduces Cr(VI)-induced CSC-like property, cell transformation, and tumorigenesis mainly through down-regulating c-Myc expression. Together, these findings indicate that chronic low dose Cr(VI) exposure induces CSC-like property and tumorigenesis by increasing c-Myc expression through down-regulating the level of miR-494, revealing an important role of the proto-oncogene c-Myc in Cr(VI) carcinogenesis.
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Affiliation(s)
- Zhishan Wang
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, Kentucky 40536
| | - Hsuan-Pei Lin
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, Kentucky 40536
| | - Yunfei Li
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, Kentucky 40536
| | - Hua Tao
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, Kentucky 40536
| | - Ping Yang
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, Kentucky 40536
- School of Public Health, Guangzhou Medical University, Guangzhou, Guangdong 511436, P.R. China
| | - Jie Xie
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, Kentucky 40536
- School of Health Sciences, Wuhan University, Wuhan, Hubei 430071, P.R. China
| | - Drew Maddy
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, Kentucky 40536
| | - Kazuya Kondo
- Department of Oncological Medical Services, Graduate School of Biomedical Sciences, Tokushima University Graduate School, Tokushima City 770-8509, Japan
| | - Chengfeng Yang
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, Kentucky 40536
- Center for Research on Environmental Disease, University of Kentucky College of Medicine, Lexington, Kentucky 40536
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28
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Tsuboi M, Kondo K, Soejima S, Kajiura K, Kawakita N, Toba H, Kawakami Y, Yoshida M, Takizawa H, Tangoku A. Chromate exposure induces DNA hypermethylation of the mismatch repair gene MLH1 in lung cancer. Mol Carcinog 2019; 59:24-31. [PMID: 31579968 DOI: 10.1002/mc.23125] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 09/19/2019] [Accepted: 09/23/2019] [Indexed: 12/31/2022]
Abstract
Hexavalent chromium is recognized as a human carcinogen. Our previous studies revealed that lung cancer (LC) in chromate-exposed workers (chromate LC) had molecular features of frequent microsatellite instability (MSI), repression of MLH1 level, and aberrant DNA methylation of several tumor-suppressor genes, including MLH1. In the present study, we quantitatively investigated MLH1-promoter methylation status using bisulfite pyrosequencing of paired tumorous/nontumorous tissues from chromate and nonchromate LCs to determine the effect of chromate exposure on MLH1-promoter methylation. The methylation level of MLH1 promoter was significantly higher in chromate LC tumors (P < .001) than nonchromate LC tumors and, among chromate LC, significantly higher in tumorous tissue than nontumorous tissue (P = .004). Moreover, the methylation level of MLH1 promoter in normal lung tissue tended to be higher in chromate LC than nonchromate LC (P = .062). In addition, LC with reduced levels of MLH1 showed significantly higher methylation levels of MLH1 promoter than LC exhibiting normal MLH1 levels (P = .019). Moreover, immunohistochemical analyses determined that levels of SUV39H1, an H3K9me2-related methyltransferase, were higher in chromate LC than nonchromate LC (P = .076). Furthermore, we evaluated three DNA double-strand break-repair genes (MRE11, RAD50, and DNA-PKcs) as possible targets of MSI by fragment-length polymorphism analysis, revealing the mutation frequency of RAD50 as significantly higher in chromate LC than nonchromate LC (P = .047). These results suggest that chromate exposure might induce MLH1 hypermethylation in LC as a mechanism of chromate-induced carcinogenesis.
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Affiliation(s)
- Mitsuhiro Tsuboi
- Department of Thoracic, Endocrine Surgery and Oncology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Kazuya Kondo
- Department of Oncological Medical Services, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Shiho Soejima
- Department of Oncological Medical Services, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Koichiro Kajiura
- Department of Thoracic, Endocrine Surgery and Oncology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Naoya Kawakita
- Department of Thoracic, Endocrine Surgery and Oncology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Hiroaki Toba
- Department of Thoracic, Endocrine Surgery and Oncology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Yukikiyo Kawakami
- Department of Thoracic, Endocrine Surgery and Oncology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Mitsuteru Yoshida
- Department of Thoracic, Endocrine Surgery and Oncology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Hiromitsu Takizawa
- Department of Thoracic, Endocrine Surgery and Oncology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Akira Tangoku
- Department of Thoracic, Endocrine Surgery and Oncology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
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29
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Li L, Zhang X, Tian T, Pang L. Mathematical modelling the pathway of genomic instability in lung cancer. Sci Rep 2019; 9:14136. [PMID: 31575883 PMCID: PMC6773729 DOI: 10.1038/s41598-019-50500-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 09/12/2019] [Indexed: 12/29/2022] Open
Abstract
Genomic instability plays a significant role in lung cancer. Although substantial research has been conducted using both clinical and theoretical studies, it is still a hotly debated issue to whether genomic instability is necessary or whether genomic instability precedes oncogenes activation and tumor suppressor genes inactivation for lung cancer. In response to this issue, we come up with a mathematical model incorporating effects of genomic instability to investigate the genomic instability pathway of human lung cancer. The presented model are applied to match the incidence rate data of lung cancer from the Life Span Study cohort of the atomic bomb survivors in Nagasaki and Hiroshima and the Surveillance Epidemiology and End Results registry in the United States. Model results suggest that genomic instability is necessary in the tumorigenesis of lung cancer, and genomic instability has no significant impact on the net proliferation rate of cells by statistical criteria. By comparing the results of the LSS data to those of the SEER data, we conclude that the genomic instability pathway exhibits a sensitivity to radiation exposure, more intensive in male patients.
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Affiliation(s)
- Lingling Li
- School of Science, Xi'an Polytechnic University, Xi'an, 710048, P.R. China.
| | - Xinan Zhang
- School of Mathematics and Statistics, Central China Normal University, Wuhan, 430079, P.R. China
| | - Tianhai Tian
- School of Mathematical Science, Monash University, Melbourne, Vic 3800, Australia
| | - Liuyong Pang
- School of Mathematics, Huanghuai University, Zhumadian, Henan, P.R. China
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30
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Wang Z, Yang C. Metal carcinogen exposure induces cancer stem cell-like property through epigenetic reprograming: A novel mechanism of metal carcinogenesis. Semin Cancer Biol 2019; 57:95-104. [PMID: 30641125 PMCID: PMC6625953 DOI: 10.1016/j.semcancer.2019.01.002] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2018] [Revised: 01/08/2019] [Accepted: 01/10/2019] [Indexed: 12/13/2022]
Abstract
Arsenic, cadmium, nickel and hexavalent chromium are among the most common environmental pollutants and potent carcinogens. Chronic exposure to these metals causes various types of cancer in humans, representing a significant environmental health issue. Although under active investigation, the mechanisms of metal carcinogenesis have not been clearly defined. One common feature of these metal carcinogens is that they are all able to cause various epigenetic dysregulations, which are believed to play important roles in their carcinogenicity. However, how metal carcinogen-caused epigenetic dysregulation contributes to metal carcinogenesis remains largely unknown. The evolution of cancer stem cell (CSC) theory has opened exciting new avenues for studying the mechanism of metal carcinogenesis. Increasing evidence indicates that chronic metal carcinogen exposure produces CSC-like cells through dysregulated epigenetic mechanisms. This review will first provide some brief introductions about CSC, epigenetics and epigenetic regulation of CSCs; then summarize progresses in recent studies on metal carcinogen-induced CSC-like property through epigenetic reprograming as a novel mechanism of metal carcinogenesis. Some perspectives for future studies in this field are also presented.
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Affiliation(s)
- Zhishan Wang
- Department of Toxicology and Cancer Biology, College of Medicine, University of Kentucky, Lexington, KY, United States.
| | - Chengfeng Yang
- Department of Toxicology and Cancer Biology, College of Medicine, University of Kentucky, Lexington, KY, United States; Center for Research on Environment Disease, College of Medicine, University of Kentucky, Lexington, KY, United States.
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31
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Chen QY, Murphy A, Sun H, Costa M. Molecular and epigenetic mechanisms of Cr(VI)-induced carcinogenesis. Toxicol Appl Pharmacol 2019; 377:114636. [PMID: 31228494 DOI: 10.1016/j.taap.2019.114636] [Citation(s) in RCA: 92] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 06/17/2019] [Accepted: 06/18/2019] [Indexed: 12/11/2022]
Abstract
Chromium (Cr) is a naturally occurring metallic element found in the Earth's crust. While trivalent chromium ([Cr(III)] is considered non-carcinogenic, hexavalent chromium [Cr(VI)] has long been established as an IARC class I human carcinogen, known to induce cancers of the lung. Current literature suggests that Cr(VI) is capable of inducing carcinogenesis through both genetic and epigenetic mechanisms. Although much has been learned about the molecular etiology of Cr(VI)-induced lung carcinogenesis, more remains to be explored. In particular, the explicit epigenetic alterations induced by Cr(VI) in lung cancer including histone modifications and miRNAs, remain understudied. Through comprehensive review of available literature found between 1973 and 2019, this article provides a summary of updated understanding of the molecular mechanisms of Cr(VI)-carcinogenesis. In addition, this review identifies potential research gaps in the areas of histone modifications and miRNAs, which may prompt new niches for future research.
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Affiliation(s)
- Qiao Yi Chen
- Department of Environmental Medicine, New York University School of Medicine, 341 East 25 Street, New York, NY 10016, United States of America.
| | - Anthony Murphy
- Department of Environmental Medicine, New York University School of Medicine, 341 East 25 Street, New York, NY 10016, United States of America.
| | - Hong Sun
- Department of Environmental Medicine, New York University School of Medicine, 341 East 25 Street, New York, NY 10016, United States of America.
| | - Max Costa
- Department of Environmental Medicine, New York University School of Medicine, 341 East 25 Street, New York, NY 10016, United States of America.
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32
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Zablon HA, VonHandorf A, Puga A. Chromium exposure disrupts chromatin architecture upsetting the mechanisms that regulate transcription. Exp Biol Med (Maywood) 2019; 244:752-757. [PMID: 30935235 PMCID: PMC6567585 DOI: 10.1177/1535370219839953] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
IMPACT STATEMENT This mini-review highlights current evidence on the mechanisms through which hexavalent chromium (Cr(VI)) disrupts transcriptional regulation, an emerging area of interest and one of the central processes by which chromium induces carcinogenesis. Several studies have shown that Cr(VI) causes widespread DNA damage and disrupts epigenetic signatures, suggesting that chromatin may be a direct Cr(VI) target. The findings discussed here suggest that Cr(VI) disrupts transcriptional regulation by causing genomic architecture changes.
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Affiliation(s)
- Hesbon A Zablon
- Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Andrew VonHandorf
- Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Alvaro Puga
- Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
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33
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Silva IR, Ramos MCAS, Arantes LMRB, Lengert AVH, Oliveira MA, Cury FP, Martins Pereira G, Santos AG, Barbosa F, Vasconcellos PC, Cuenin C, Herceg Z, Silveira HCS. Evaluation of DNA Methylation Changes and Micronuclei in Workers Exposed to a Construction Environment. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:E902. [PMID: 30871143 PMCID: PMC6466300 DOI: 10.3390/ijerph16060902] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 02/24/2019] [Accepted: 03/04/2019] [Indexed: 12/15/2022]
Abstract
Methylation levels in tumor-suppressor genes and repetitive sequences have previously been used to study the relationship between environmental air pollution and epigenetic changes related to cancer. In this study, we measured the methylation profiles of the promoter regions CDKN2A, MLH1 and APC and the repetitive sequence LINE-1 in 59 workers exposed to the construction environment and in 49 unexposed workers. We also evaluated the micronuclei frequency and levels of trace elements in the blood of all workers. We evaluated of levels of particulate matter and polycyclic aromatic hydrocarbons (PAHs) at the construction site to characterize the environmental exposure. Our findings demonstrated that exposed workers exhibited significantly higher average levels of promoter methylation of CDKN2A, APC, and MLH1 genes and increased hypomethylation of the LINE-1 in comparison to unexposed workers (all p < 0.05). A higher frequency of micronuclei was observed in the exposed group (2 ± 2) compared to the unexposed group (1 ± 1) with p < 0.001. High levels of particulate matter (51⁻841 μg/m³) and some PAHs were found in samples from the construction environment. In summary, we provide evidence of increased DNA damage and altered DNA methylation of exposed workers, suggesting that genomic approaches to biomonitoring may be an effective way of estimating future cancer risk for construction workers.
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Affiliation(s)
- Isana R Silva
- Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos 14784-400, São Paulo, Brazil.
| | - Manoela C A S Ramos
- Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos 14784-400, São Paulo, Brazil.
| | - Lídia M R B Arantes
- Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos 14784-400, São Paulo, Brazil.
| | - André V H Lengert
- Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos 14784-400, São Paulo, Brazil.
| | - Marco A Oliveira
- Center for Research Support (NAP), Barretos Cancer Hospital, Barretos 14784-400, São Paulo, Brazil.
| | - Fernanda P Cury
- Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos 14784-400, São Paulo, Brazil.
| | | | | | - Fernando Barbosa
- School of Pharmaceutical Sciences, University of São Paulo, Ribeirão Preto 14040-903, São Paulo, Brazil.
| | | | - Cyrille Cuenin
- Epigenetics Group, International Agency for Research on Cancer (IARC), 150 Cours Albert-Thomas, 69008 Lyon, France.
| | - Zdenko Herceg
- Epigenetics Group, International Agency for Research on Cancer (IARC), 150 Cours Albert-Thomas, 69008 Lyon, France.
| | - Henrique C S Silveira
- Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos 14784-400, São Paulo, Brazil.
- University of Cuiabá, Campus Beira Rio, Cuiabá 78008-000, Mato Grosso, Brazil.
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34
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Rager JE, Suh M, Chappell GA, Thompson CM, Proctor DM. Review of transcriptomic responses to hexavalent chromium exposure in lung cells supports a role of epigenetic mediators in carcinogenesis. Toxicol Lett 2019; 305:40-50. [PMID: 30690063 DOI: 10.1016/j.toxlet.2019.01.011] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Revised: 01/17/2019] [Accepted: 01/25/2019] [Indexed: 12/14/2022]
Abstract
Inhalation exposure to hexavalent chromium [Cr(VI)] is associated with increased risk of lung cancer with a mode of action (MOA) postulated to involve non-mutagenic key events, yet molecular-level events remain uncertain. Previously-published transcriptomic studies in the lung and lung cells were reviewed to evaluate molecular events in the MOA. This study aimed to (i) identify biological pathways that are consistently modulated by Cr(VI) in the lung through the compilation of transcriptomic-based databases, (ii) predict interactions between epigenetic regulators and transcriptional responses, and (iii) relate findings to previous literature to postulate a mechanism of action underlying Cr(VI)-induced lung cancer involving changes in genomic/epigenomic signatures. This cross-study comparison identified 372 genes with Cr(VI)-induced expression alterations in multiple studies. Pathway enrichment analyses of the commonly modulated genes demonstrated that pathways involved in cytotoxicity / cell proliferation were highly enriched, as well as the general suppression of genes involved in DNA damage repair. These signaling alterations were predicted to be regulated by DNA methylation, histone modifications, and microRNAs; and published evidence substantiates the role of these epigenetic regulators in Cr(VI)-induced carcinogenicity. Findings support the influence of epigenetic alterations on cell signaling related to Cr(VI)-induced cytotoxicity/cell proliferation, and decreases in DNA repair signaling leading to tumorigenesis.
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Affiliation(s)
- Julia E Rager
- ToxStrategies, Inc., Austin, TX, 78759, United States
| | - Mina Suh
- ToxStrategies, Inc., Mission Viejo, CA, 92692, United States
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35
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Guo X, Feng L, Lemos B, Lou J. DNA methylation modifications induced by hexavalent chromium. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART C, ENVIRONMENTAL CARCINOGENESIS & ECOTOXICOLOGY REVIEWS 2019; 37:133-145. [PMID: 31084241 PMCID: PMC8479272 DOI: 10.1080/10590501.2019.1592640] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Hexavalent chromium [Cr (VI)] contributes a significant health risk and causes a number of chronic diseases and cancers. While the genotoxic and carcinogenic effects of hexavalent chromium exposure are explicit and better-characterized, the exact mechanism underlying the carcinogenic process of Cr (VI) is still a matter of debate. In recent years, studies have shown that epigenetic modifications, especially DNA methylation, may play a significant role in Cr (VI)-induced carcinogenesis. The aim of this review is to summarize our understanding regarding the effects of Cr (VI) on global and gene-specific DNA methylation.
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Affiliation(s)
- Xinnian Guo
- Institute of Occupation Diseases, Zhejiang Academy of Medical Sciences, Hangzhou, 310013, Zhejiang, P.R.China
| | - Lingfang Feng
- Institute of Occupation Diseases, Zhejiang Academy of Medical Sciences, Hangzhou, 310013, Zhejiang, P.R.China
| | - Bernardo Lemos
- Program in Molecular and Integrative Physiological Sciences, Department of Environmental Health, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Jianlin Lou
- Institute of Occupation Diseases, Zhejiang Academy of Medical Sciences, Hangzhou, 310013, Zhejiang, P.R.China
- Corresponding author at: Institute of Occupation Diseases, Zhejiang Academy of Medical Sciences, 182 Tianmushan Road, Hangzhou, 310013, P.R.C. Telephone: +86-571-88215566. Fax: +86-571-88215576.
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36
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Alvarado-Cruz I, Alegría-Torres JA, Montes-Castro N, Jiménez-Garza O, Quintanilla-Vega B. Environmental Epigenetic Changes, as Risk Factors for the Development of Diseases in Children: A Systematic Review. Ann Glob Health 2018; 84:212-224. [PMID: 30873799 PMCID: PMC6748183 DOI: 10.29024/aogh.909] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Children are susceptible to environmental contaminants and are at risk of developing diseases, more so if the exposure begins at an early age. Epidemiological studies have postulated the hypothesis of the fetal origin of disease, which is mediated by epigenetic changes. Epigenetic marks are inheritable; they modulate the gene expression and can affect human health due to the presence of environmental factors. OBJECTIVE This review focuses on DNA-methylation and its association with environmental-related diseases in children. METHODS A search for studies related to DNA-methylation in children by pre- or post-natal environmental exposures was conducted, and those studies with appropriate designs and statistical analyses and evaluations of the exposure were selected. FINDINGS Prenatal and early life environmental factors, from diet to exposure to pollutants, have been associated with epigenetic changes, specifically DNA-methylation. Thus, maternal nutrition and smoking and exposure to air particulate matter, polycyclic aromatic hydrocarbons, arsenic, heavy metals, persistent organic pollutants, and some endocrine disrupters during pregnancy have been associated with genomic and gene-specific newborns' DNA-methylation changes that have shown in some cases sex-specific patterns. In addition, these maternal factors may deregulate the placental DNA-methylation balance and could induce a fetal reprogramming and later-in-life diseases. CONCLUSIONS Exposure to environmental pollutants during prenatal and early life can trigger epigenetic imbalances and eventually the development of diseases in children. The integration of epigenetic data should be considered in future risk assessments.
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Affiliation(s)
| | | | | | - Octavio Jiménez-Garza
- Health Sciences Division, University of Guanajuato, Leon Campus, Leon, Guanajuato, MX
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Wang Z, Wu J, Humphries B, Kondo K, Jiang Y, Shi X, Yang C. Upregulation of histone-lysine methyltransferases plays a causal role in hexavalent chromium-induced cancer stem cell-like property and cell transformation. Toxicol Appl Pharmacol 2018; 342:22-30. [PMID: 29391238 PMCID: PMC5825290 DOI: 10.1016/j.taap.2018.01.022] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 01/24/2018] [Accepted: 01/28/2018] [Indexed: 02/08/2023]
Abstract
While hexavalent chromium [Cr(VI)] is generally considered as a genotoxic environmental carcinogen, studies showed that Cr(VI) exposure also causes epigenetic changes. However, whether Cr(VI)-caused epigenetic dysregulations plays an important role in Cr(VI) carcinogenicity remain largely unknown. The aim of this study was to determine if chronic low dose Cr(VI) exposure causes epigenetic changes, the underlying mechanism and whether chronic low dose Cr(VI) exposure-caused epigenetic dysregulation contributes causally to Cr(VI)-induced cancer stem cell (CSC)-like property and cell transformation. Two immortalized human bronchial epithelial cell lines (BEAS-2B and 16HBE) were exposed to 0.25 μM of K2Cr2O7 for 20 and 40 weeks to induce cell transformation, respectively. Cr(VI)-induced epigenetic changes were examined in Cr(VI)-transformed cells and Cr(VI) exposure-caused human lung cancer tissues. Pharmacological inhibitors and gene knockdown experiments were used to determine the role of epigenetic dysregulation in Cr(VI) carcinogenicity. We found that chronic Cr(VI) exposure causes epigenetic dysregulation as evidenced by the increased levels of histone H3 repressive methylation marks (H3K9me2 and H3K27me3) and the related histone-lysing methyltransferases (HMTases). Pharmacological inhibition or knockdown of HMTases reduces H3 repressive methylation marks and malignant phenotypes of Cr(VI)-transformed cells. Moreover, knockdown of HMTases in parental cells significantly reduces chronic Cr(VI) exposure-induced CSC-like property and cell transformation. Further mechanistic study revealed that knockdown of HMTases decreases Cr(VI) exposure-caused DNA damage. Our findings indicate that chronic Cr(VI) exposure increases H3 repressive methylation marks by increasing the related HMTases expression; and that increased expression of HMTases plays a causal role in Cr(VI)-induced CSC-like property and cell transformation.
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Affiliation(s)
- Zhishan Wang
- Center for Research on Environmental Disease, University of Kentucky College of Medicine, Lexington, KY, USA; Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Jianjun Wu
- Center for Research on Environmental Disease, University of Kentucky College of Medicine, Lexington, KY, USA; Institute for Chemical Carcinogenesis, State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Guangzhou, Guangdong, PR China
| | - Brock Humphries
- Department of Radiology, University of Michigan, Ann Arbor, MI, USA
| | - Kazuya Kondo
- Department of Oncological Medical Services, Graduate School of Biomedical Sciences, Tokushima University Graduate School, Tokushima city, Japan
| | - Yiguo Jiang
- Institute for Chemical Carcinogenesis, State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Guangzhou, Guangdong, PR China
| | - Xianglin Shi
- Center for Research on Environmental Disease, University of Kentucky College of Medicine, Lexington, KY, USA; Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Chengfeng Yang
- Center for Research on Environmental Disease, University of Kentucky College of Medicine, Lexington, KY, USA; Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, KY, USA.
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Martin EM, Fry RC. Environmental Influences on the Epigenome: Exposure- Associated DNA Methylation in Human Populations. Annu Rev Public Health 2018; 39:309-333. [PMID: 29328878 DOI: 10.1146/annurev-publhealth-040617-014629] [Citation(s) in RCA: 371] [Impact Index Per Article: 61.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
DNA methylation is the most well studied of the epigenetic regulators in relation to environmental exposures. To date, numerous studies have detailed the manner by which DNA methylation is influenced by the environment, resulting in altered global and gene-specific DNA methylation. These studies have focused on prenatal, early-life, and adult exposure scenarios. The present review summarizes currently available literature that demonstrates a relationship between DNA methylation and environmental exposures. It includes studies on aflatoxin B1, air pollution, arsenic, bisphenol A, cadmium, chromium, lead, mercury, polycyclic aromatic hydrocarbons, persistent organic pollutants, tobacco smoke, and nutritional factors. It also addresses gaps in the literature and future directions for research. These gaps include studies of mixtures, sexual dimorphisms with respect to environmentally associated methylation changes, tissue specificity, and temporal stability of the methylation marks.
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Affiliation(s)
- Elizabeth M Martin
- Department of Environmental Sciences and Engineering, and Curriculum in Toxicology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina 27599, USA; ,
| | - Rebecca C Fry
- Department of Environmental Sciences and Engineering, and Curriculum in Toxicology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina 27599, USA; ,
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Hu H, Chen X, Zhou C, Li B, Yang Y, Ying X, Mao Y, Zhang Y, Zhong J, Dai J, Yu H, Wu B, Li X, Wang T, Duan S. Aberrant methylation of mutL homolog 1 is associated with increased risk of non-small cell lung cancer. J Clin Lab Anal 2017; 32:e22370. [PMID: 29205508 DOI: 10.1002/jcla.22370] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 11/13/2017] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Non-small cell lung cancer (NSCLC) is a common malignant tumor. DNA hypermethylation in the promoter region has been served as a potential molecular marker for several tumors. The goal of the current study was to assess the diagnostic ability of mutL homolog 1 (MLH1) promoter methylation in NSCLC. METHODS A total of 111 NSCLC patients' paired tissue samples were obtained to explore the association between MLH1 promoter methylation and NSCLC by methylation-specific polymerase chain reaction (MSP) method. Public databases including The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) were used to verify our findings. RESULTS Our results showed a significantly higher MLH1 methylation frequency in tumor tissue samples than their paired adjacent tissues (P = .008). ROC curve indicated that MLH1MSP assay was a sensitive but not a specific method in the diagnosis for NSCLC (sensitivity = 0.964, specificity = 0.135, AUC = 0.550). And the association between the methylation level and clinical characteristics has no statistical significance. TCGA cohort evinced a higher methylation probability in tumor group compared with nontumor group (the mean β value: -0.449 [-0.467, -0.437] vs -0.466 [-0.472, -0.437], P = .011), which was consistent with our results. Meanwhile, an inverse correlation between MLH1 methylation and MLH1 expression was detected in TCGA and GEO databases. CONCLUSIONS The MSP method for MLH1 methylation was a sensitive but not a specific diagnostic method for NSCLC.
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Affiliation(s)
- Haochang Hu
- Medical Genetics Center, School of Medicine, Ningbo University, Ningbo, Zhejiang, China
| | - Xiaoying Chen
- Department of Medical Record, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Cong Zhou
- Medical Genetics Center, School of Medicine, Ningbo University, Ningbo, Zhejiang, China
| | - Bin Li
- Medical Genetics Center, School of Medicine, Ningbo University, Ningbo, Zhejiang, China
| | - Yong Yang
- Medical Genetics Center, School of Medicine, Ningbo University, Ningbo, Zhejiang, China
| | - Xiuru Ying
- Medical Genetics Center, School of Medicine, Ningbo University, Ningbo, Zhejiang, China
| | - Yiyi Mao
- Medical Genetics Center, School of Medicine, Ningbo University, Ningbo, Zhejiang, China
| | - Yihan Zhang
- Medical Genetics Center, School of Medicine, Ningbo University, Ningbo, Zhejiang, China
| | - Jie Zhong
- Medical Genetics Center, School of Medicine, Ningbo University, Ningbo, Zhejiang, China
| | - Jie Dai
- Medical Genetics Center, School of Medicine, Ningbo University, Ningbo, Zhejiang, China
| | - Hang Yu
- Medical Genetics Center, School of Medicine, Ningbo University, Ningbo, Zhejiang, China
| | - Boyi Wu
- Medical Genetics Center, School of Medicine, Ningbo University, Ningbo, Zhejiang, China
| | - Xiaodong Li
- Medical Genetics Center, School of Medicine, Ningbo University, Ningbo, Zhejiang, China
| | - Tiangong Wang
- Medical Genetics Center, School of Medicine, Ningbo University, Ningbo, Zhejiang, China
| | - Shiwei Duan
- Medical Genetics Center, School of Medicine, Ningbo University, Ningbo, Zhejiang, China
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Abstract
Epigenetics is the study of heritable changes in gene expression that occur without alterations in the DNA sequence. Several studies have shown that environmental chemicals can alter epigenetic modifications, including histone modifications and DNA methylation. Environmental chemicals may show toxic effects via epigenetic mechanism-regulated changes in gene expression. Previously, we reported that zinc treatment rapidly decreased Lys(4)-trimethylated and Lys(9)-acetylated histone H3 in the metallothionein (MT) promoter, and also decreased total histone H3. The chromatin structure in the MT promoter may be locally disrupted by zinc-induced nucleosome removal. We also showed that chromium (VI) inhibited MT gene transcription by modifying the transcription potential of the co-activator p300. MT is a small cysteine-rich protein that is active in zinc homeostasis, cadmium detoxification, and protection against reactive oxygen species. Epigenetic changes might influence the cytoprotective function of the MT gene. In this review, I briefly summarize the results of previous studies and discuss the mechanisms and toxicological significance of metal-mediated epigenetic modifications.
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Affiliation(s)
- Tomoki Kimura
- Department of Life Science, Faculty of Science and Engineering, Setsunan University
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41
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Dual action of chromium-reducing and nitrogen-fixing Bacillus megaterium-ASNF3 for improved agro-rehabilitation of chromium-stressed soils. 3 Biotech 2016; 6:125. [PMID: 28330201 PMCID: PMC4909028 DOI: 10.1007/s13205-016-0443-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 05/25/2016] [Indexed: 11/06/2022] Open
Abstract
We conducted a study for enhanced biological rehabilitation of chromium-contaminated soils using a chromium-reducing and nitrogen-fixing bacterial species (Bacillus megaterium-ASNF3). The bacterial species was isolated from a chromium-rich land area, characterized, and employed under optimum conditions for the treatment of artificially prepared chromium-rich soil. The bacterium reduced Cr(VI) up to 86 % in a 60-day trial of incubation in the soil bioreactor. The nitrogenase activity of the bacterium yielded up to 486 nmol of ethylene/mL/h after an incubation period of 40 days when it was optimally cultured in growth medium at neutral pH and 30 °C. Although the nitrogen-fixing ability of the bacterium reduced significantly in the presence of 1000 ppm of Cr(VI), yet, the bacterium was proved to be a potential bio-fertilizer for enhancing nitrogen contents of the contaminated soil even under the higher chromium stress, together with the metal reduction. In the biologically treated soil, higher values of wheat growth variables were achieved. Application of metal-resistant B. megaterium-ASNF3 in selected situations rendered chromium-laden soils arable with significant increment in crop-yield parameters.
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Hu G, Liu J, Zhang Y, Zheng P, Wang L, Zhao L, Xu H, Chen Z, Wang T, Jia G. Gene expression profiling and bioinformatics analysis in 16HBE cells treated by chromium (VI). Toxicol Lett 2016; 264:71-78. [DOI: 10.1016/j.toxlet.2016.10.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 10/17/2016] [Accepted: 10/24/2016] [Indexed: 10/20/2022]
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Duppel U, Woenckhaus M, Schulz C, Merk J, Dietmaier W. Quantitative detection of TUSC3 promoter methylation -a potential biomarker for prognosis in lung cancer. Oncol Lett 2016; 12:3004-3012. [PMID: 27698890 PMCID: PMC5038372 DOI: 10.3892/ol.2016.4927] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 06/17/2016] [Indexed: 11/06/2022] Open
Abstract
Aberrant promoter methylation of tumor relevant genes frequently occurs in early steps of carcinogenesis and during tumor progression. Epigenetic alterations could be used as potential biomarkers for early detection and for prediction of prognosis and therapy response in lung cancer. The present study quantitatively analyzed the methylation status of known and potential gatekeeper and tumor suppressor genes [O-6-methylguanine-DNA methyltransferase (MGMT), Ras association domain family member 1A (RASSF1A), Ras protein activator like 1 (RASAL1), programmed cell death 4 (PDCD4), metastasis suppressor 1 (MTSS1) and tumor suppressor candidate 3 (TUSC3)] in 42 lung cancers and in corresponding non-malignant bronchus and lung tissue using bisulfite-conversion independent methylation-quantification of endonuclease-resistant DNA (MethyQESD). Methylation status was associated with clinical and pathological parameters. No methylation was found in the promoter regions of PDCD4 and MTSS1 of either compartment. MGMT, RASSF1A and RASAL1 showed sporadic (up to 26.2%) promoter methylation. The promoter of TUSC3, however, was frequently methylated in the tumor (59.5%), benign bronchus (67.9%) and alveolar lung (31.0%) tissues from each tumor patient. The methylation status of TUSC3 was significantly associated with smaller tumor size (P=0.008) and a longer overall survival (P=0.013). Pooled blood DNA of healthy individuals did not show any methylation of either gene. Therefore, methylation of TUSC3 shows prognostic and pathobiological relevance in lung cancer. Furthermore, quantitative detection of TUSC3 promoter methylation appears to be a promising tool for early detection and prediction of prognosis in lung cancer. However, additional studies are required to confirm this finding.
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Affiliation(s)
- Uta Duppel
- Institute of Pathology, University of Regensburg, D-93053 Regensburg, Bavaria, Germany
| | | | - Christian Schulz
- Department of Internal Medicine II, University Hospital Regensburg, D-93053 Regensburg, Bavaria, Germany
| | - Johannes Merk
- Department of Thoracic Surgery, University Hospital Regensburg, D-93053 Regensburg, Bavaria, Germany
| | - Wolfgang Dietmaier
- Institute of Pathology, University of Regensburg, D-93053 Regensburg, Bavaria, Germany
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Wang Y, Wu W, Yao C, Lou J, Chen R, Jin L, Wu N, Gao M, Song P, Tan Y, Liu K. Elevated tissue Cr levels, increased plasma oxidative markers, and global hypomethylation of blood DNA in male Sprague-Dawley rats exposed to potassium dichromate in drinking water. ENVIRONMENTAL TOXICOLOGY 2016; 31:1080-1090. [PMID: 25846368 DOI: 10.1002/tox.22117] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Revised: 12/31/2014] [Accepted: 01/01/2015] [Indexed: 06/04/2023]
Abstract
Hexavalent chromium [Cr (VI)] is prevalent in ground water in some areas, but evidence on the toxic effects of Cr (VI) via ingestion through drinking water remains insufficient. The aims of our study were to investigate the toxic effects of Cr (VI) through oral water ingestion on oxidative stress and DNA methylation. Thirty-two Sprague-Dawley rats were randomly divided into four groups, and exposed to porassium dichromate (K2 Cr2 O7 ; 0, 30, 100, and 300 mg/L) in drinking water for 4 weeks. Mean body weight gain, mean water consumption, clinical chemistry determinations, and oxidative stress levels in plasma were measured. Global DNA methylation changes and DNA methylation status at the promoter of p16 gene were also detected. After 4 weeks, mild anemic effects and increased plasma malondialdehyde (MDA) levels occurred in rats exposed to 100 mg/L or 300 mg/L of Cr (VI). Plasma glutathione peroxidase (GSH-Px) activity decreased in all exposed groups. Global DNA methylation levels were reduced in 100 mg/L and 300 mg/L exposure groups. However, DNA methylation status at the promoter of P16 gene remained unchanged in all K2 Cr2 O7- treated groups. The correlation analysis indicated that increased MDA levels were closely correlated to global DNA hypomethylation. Our results indicated that oral ingestion of Cr (VI) through drinking water caused not only oxidative stress in plasma, but also global DNA hypomethylation in blood cells from male rats, and a good correlation was found between increased MDA levels and reduced global DNA methylation. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1080-1090, 2016.
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Affiliation(s)
- Yu Wang
- Institute of Occupational Disease, Zhejiang Academy of Medical Sciences, Hangzhou, Zhejiang, People's Republic of China
| | - Wei Wu
- Eye Center, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China; and Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou, China
| | - Chunji Yao
- Institute of Occupational Disease, Zhejiang Academy of Medical Sciences, Hangzhou, Zhejiang, People's Republic of China
| | - Jianlin Lou
- Institute of Occupational Disease, Zhejiang Academy of Medical Sciences, Hangzhou, Zhejiang, People's Republic of China
| | - Riping Chen
- Institute of Occupational Disease, Zhejiang Academy of Medical Sciences, Hangzhou, Zhejiang, People's Republic of China
| | - Lingzhi Jin
- Institute of Occupational Disease, Zhejiang Academy of Medical Sciences, Hangzhou, Zhejiang, People's Republic of China
| | - Nanxiang Wu
- Institute of Occupational Disease, Zhejiang Academy of Medical Sciences, Hangzhou, Zhejiang, People's Republic of China
| | - Ming Gao
- Institute of Occupational Disease, Zhejiang Academy of Medical Sciences, Hangzhou, Zhejiang, People's Republic of China
| | - Peng Song
- Institute of Occupational Disease, Zhejiang Academy of Medical Sciences, Hangzhou, Zhejiang, People's Republic of China
| | - Yufeng Tan
- Institute of Occupational Disease, Zhejiang Academy of Medical Sciences, Hangzhou, Zhejiang, People's Republic of China
| | - Kecheng Liu
- Institute of Occupational Disease, Zhejiang Academy of Medical Sciences, Hangzhou, Zhejiang, People's Republic of China
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Han Y, Shi K, Zhou SJ, Yu DP, Liu ZD. The clinicopathological significance of hMLH1 hypermethylation in non-small-cell lung cancer: a meta-analysis and literature review. Onco Targets Ther 2016; 9:5081-90. [PMID: 27574449 PMCID: PMC4993409 DOI: 10.2147/ott.s106345] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The hMLH1 gene plays an essential role in DNA repair. Methylation of the hMLH1 gene is common in many types of cancer and can lead to the loss of hMLH1 expression. However, the association and clinicopathological significance between hMLH1 promoter hypermethylation and non-small-cell lung cancer (NSCLC) is elusive. Here, we investigated the correlation of hMLH1 promoter hypermethylation and NSCLC using 13 studies by comprising 1,056 lung cancer patients via a meta-analysis. We observed that 1) loss of hMLH1 protein expression was significantly associated with its promoter hypermethylation, 2) hMLH1 gene inactivation through hypermethylation contributed to the tumorigenesis of NSCLC, which could be a decisive factor for the pathogenesis of NSCLC due to its high occurrence in NSCLC tissues compared to normal lung tissues, 3) a correlation exists between histologic subtypes/disease stages (TNM I+II vs III+IV) and hypermethylation status of hMLH1 gene, and 4) NSCLC patients with hMLH1 hypermethylation and subsequent low expression levels of hMLH1 have a short overall survival period than those patients with normal expression of hMLH1 gene. hMLH1 mRNA predicts patient survival in lung cancer, and this was confirmed by using a public database. We then discussed the tumor suppressor function of hMLH1 and the clinicopathological significance of hMLH1 in NSCLC. We concluded that hMLH1 hypermethylation should be an early diagnostic marker for NSCLC and also a prognostic index for NSCLC. hMLH1 is an interesting therapeutic target in human lung cancers.
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Affiliation(s)
- Yi Han
- Department of Thoracic Surgery, Beijing Chest Hospital, Capital Medical University, Beijing, People's Republic of China
| | - Kang Shi
- Department of Thoracic Surgery, Beijing Chest Hospital, Capital Medical University, Beijing, People's Republic of China
| | - Shi-Jie Zhou
- Department of Thoracic Surgery, Beijing Chest Hospital, Capital Medical University, Beijing, People's Republic of China
| | - Da-Ping Yu
- Department of Thoracic Surgery, Beijing Chest Hospital, Capital Medical University, Beijing, People's Republic of China
| | - Zhi-Dong Liu
- Department of Thoracic Surgery, Beijing Chest Hospital, Capital Medical University, Beijing, People's Republic of China
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Hu G, Li P, Li Y, Wang T, Gao X, Zhang W, Jia G. Methylation levels of P16 and TP53 that are involved in DNA strand breakage of 16HBE cells treated by hexavalent chromium. Toxicol Lett 2016; 249:15-21. [DOI: 10.1016/j.toxlet.2016.03.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 01/19/2016] [Accepted: 03/07/2016] [Indexed: 01/10/2023]
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47
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Azar SK, Azar SS. Waste Related Pollutions and Their Potential Effect on Cancer Incidences in Lebanon. ACTA ACUST UNITED AC 2016. [DOI: 10.4236/jep.2016.76070] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Abstract
Hexavalent chromium [Cr(VI)] is a known carcinogen when inhaled. However, inhalational exposure to Cr(VI) affects only a small portion of the population, mainly by occupational exposures. In contrast, oral exposure to Cr(VI) is widespread and affects many people throughout the globe. In 2008, the National Toxicology Program (NTP) released a 2-year study demonstrating that ingested Cr(VI) was carcinogenic in rats and mice. The effects of Cr(VI) oral exposure are mitigated by reduction in the gut; however, a portion evades the reductive detoxification and reaches target tissues. Once Cr(VI) enters the cell, it ultimately gets reduced to Cr(III), which mediates its toxicity via induction of oxidative stress during the reduction while Cr intermediates react with protein and DNA. Cr(III) can form adducts with DNA that may lead to mutations. This review will discuss the potential adverse effects of oral exposure to Cr(VI) by presenting up-to-date human and animal studies, examining the underlying mechanisms that mediate Cr(VI) toxicity, as well as highlighting opportunities for future research.
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Affiliation(s)
- Hong Sun
- NYU School of Medicine, Department of Environmental Medicine, 57 Old Forge Road, Tuxedo, NY 10987
| | - Jason Brocato
- NYU School of Medicine, Department of Environmental Medicine, 57 Old Forge Road, Tuxedo, NY 10987
| | - Max Costa
- NYU School of Medicine, Department of Environmental Medicine, 57 Old Forge Road, Tuxedo, NY 10987
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Environmental pollution and DNA methylation: carcinogenesis, clinical significance, and practical applications. Front Med 2015; 9:261-74. [PMID: 26290283 DOI: 10.1007/s11684-015-0406-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 05/12/2015] [Indexed: 01/25/2023]
Abstract
Environmental pollution is one of the main causes of human cancer. Exposures to environmental carcinogens result in genetic and epigenetic alterations which induce cell transformation. Epigenetic changes caused by environmental pollution play important roles in the development and progression of environmental pollution-related cancers. Studies on DNA methylation are among the earliest and most conducted epigenetic research linked to cancer. In this review, the roles of DNA methylation in carcinogenesis and their significance in clinical medicine were summarized, and the effects of environmental pollutants, particularly air pollutants, on DNA methylation were introduced. Furthermore, prospective applications of DNA methylation to environmental pollution detection and cancer prevention were discussed.
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Effects of soluble and particulate Cr(VI) on genome-wide DNA methylation in human B lymphoblastoid cells. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2015; 792:12-8. [PMID: 26433257 DOI: 10.1016/j.mrgentox.2015.08.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 08/06/2015] [Accepted: 08/11/2015] [Indexed: 12/15/2022]
Abstract
Several previous studies highlighted the potential epigenetic effects of Cr(VI), especially DNA methylation. However, few studies have compared the effects of Cr(VI) on DNA methylation profiles between soluble and particulate chromate in vitro. Accordingly, Illumina Infinium Human Methylation 450K BeadChip array was used to analyze DNA methylation profiles of human B lymphoblastoid cells exposed to potassium dichromate or lead chromate, and the cell viability was also studied. Array based DNA methylation analysis showed that the impacts of Cr(VI) on DNA methylation were limited, only about 40 differentially methylated CpG sites, with an overlap of 15CpG sites, were induced by both potassium dichromate and lead chromate. The results of mRNA expression showed that after Cr(VI) treatment, mRNA expression changes of four genes (TBL1Y, FZD5, IKZF2, and KIAA1949) were consistent with their DNA methylation alteration, but DNA methylation changes of other six genes did not correlate with mRNA expression. In conclusion, both of soluble and particulate Cr(VI) could induce a small amount of differentially methylated sites in human B lymphoblastoid cells, and the correlations between DNA methylation changes and mRNA expression varied between different genes.
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