1
|
Chesnel F, Jullion E, Delalande O, Couturier A, Alusse A, Le Goff X, Lenglet M, Gardie B, Abadie C, Arlot-Bonnemains Y. Mutation of the proline P81 into a serine modifies the tumour suppressor function of the von Hippel-Lindau gene in the ccRCC. Br J Cancer 2022; 127:1954-1962. [PMID: 36175619 PMCID: PMC9681884 DOI: 10.1038/s41416-022-01985-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 08/29/2022] [Accepted: 09/07/2022] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND The von Hippel-Lindau disease is an autosomal dominant syndrome associated with tumour formation in various tissues, such as retina, central nervous system, kidney, and adrenal glands. VHL gene deletion or mutations support the development of various cancers. Unclassified VHL variants also referred as "of unknown significance" result from gene mutations that have an unknown or unclear effect on protein functions. The P81S mutation has been linked to low penetrance Type 1 disease but its pathogenic function was not clearly determined. METHODS We established a stable cell line expressing the pVHL213 (c.241C>T, P81S) mutant. Using biochemical and physiological approaches, we herein analysed pVHL folding, stability and function in the context of this VHL single missense mutation. RESULTS The P81S mutation mostly affects the non-canonical function of the pVHL protein. The cells expressing the pVHL213P81S acquire invasive properties in relation with modified architecture network. CONCLUSION We demonstrated the pathogenic role of this mutation in tumour development in vhl patients and confirm a medical follow up of family carrying the c.241C>T, P81S.
Collapse
Affiliation(s)
- Franck Chesnel
- CNRS UMR6290, Université Rennes 1, SFR-UMSCNRS 3480-INSERM 018, 2 ave du Pr L Bernard, 35042, Rennes, France
| | - Emmanuelle Jullion
- CNRS UMR6290, Université Rennes 1, SFR-UMSCNRS 3480-INSERM 018, 2 ave du Pr L Bernard, 35042, Rennes, France
| | - Olivier Delalande
- CNRS UMR6290, Université Rennes 1, SFR-UMSCNRS 3480-INSERM 018, 2 ave du Pr L Bernard, 35042, Rennes, France
| | - Anne Couturier
- CNRS UMR6290, Université Rennes 1, SFR-UMSCNRS 3480-INSERM 018, 2 ave du Pr L Bernard, 35042, Rennes, France
| | - Adrien Alusse
- CNRS UMR6290, Université Rennes 1, SFR-UMSCNRS 3480-INSERM 018, 2 ave du Pr L Bernard, 35042, Rennes, France
| | - Xavier Le Goff
- CNRS UMR6290, Université Rennes 1, SFR-UMSCNRS 3480-INSERM 018, 2 ave du Pr L Bernard, 35042, Rennes, France
| | - Marion Lenglet
- Ecole Pratique des Hautes Etudes, EPHE, Université Paris Sciences et Lettres, Paris, France
- Nantes Université, CNRS, INSERM, l'Institut du Thorax, F-44000, Nantes, France
| | - Betty Gardie
- Ecole Pratique des Hautes Etudes, EPHE, Université Paris Sciences et Lettres, Paris, France
- Nantes Université, CNRS, INSERM, l'Institut du Thorax, F-44000, Nantes, France
| | - Caroline Abadie
- Institut de Cancérologie, Boulevard Jacques Monod, 44805, Saint-Herblain, France
| | - Yannick Arlot-Bonnemains
- CNRS UMR6290, Université Rennes 1, SFR-UMSCNRS 3480-INSERM 018, 2 ave du Pr L Bernard, 35042, Rennes, France.
| |
Collapse
|
2
|
Thévenod F, Schreiber T, Lee WK. Renal hypoxia-HIF-PHD-EPO signaling in transition metal nephrotoxicity: friend or foe? Arch Toxicol 2022; 96:1573-1607. [PMID: 35445830 PMCID: PMC9095554 DOI: 10.1007/s00204-022-03285-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 03/14/2022] [Indexed: 12/18/2022]
Abstract
The kidney is the main organ that senses changes in systemic oxygen tension, but it is also the key detoxification, transit and excretion site of transition metals (TMs). Pivotal to oxygen sensing are prolyl-hydroxylases (PHDs), which hydroxylate specific residues in hypoxia-inducible factors (HIFs), key transcription factors that orchestrate responses to hypoxia, such as induction of erythropoietin (EPO). The essential TM ion Fe is a key component and regulator of the hypoxia–PHD–HIF–EPO (HPHE) signaling axis, which governs erythropoiesis, angiogenesis, anaerobic metabolism, adaptation, survival and proliferation, and hence cell and body homeostasis. However, inadequate concentrations of essential TMs or entry of non-essential TMs in organisms cause toxicity and disrupt health. Non-essential TMs are toxic because they enter cells and displace essential TMs by ionic and molecular mimicry, e. g. in metalloproteins. Here, we review the molecular mechanisms of HPHE interactions with TMs (Fe, Co, Ni, Cd, Cr, and Pt) as well as their implications in renal physiology, pathophysiology and toxicology. Some TMs, such as Fe and Co, may activate renal HPHE signaling, which may be beneficial under some circumstances, for example, by mitigating renal injuries from other causes, but may also promote pathologies, such as renal cancer development and metastasis. Yet some other TMs appear to disrupt renal HPHE signaling, contributing to the complex picture of TM (nephro-)toxicity. Strikingly, despite a wealth of literature on the topic, current knowledge lacks a deeper molecular understanding of TM interaction with HPHE signaling, in particular in the kidney. This precludes rationale preventive and therapeutic approaches to TM nephrotoxicity, although recently activators of HPHE signaling have become available for therapy.
Collapse
Affiliation(s)
- Frank Thévenod
- Institute for Physiology, Pathophysiology and Toxicology, ZBAF, Witten/Herdecke University, Stockumer Strasse 12, 58453, Witten, Germany.
| | - Timm Schreiber
- Institute for Physiology, Pathophysiology and Toxicology, ZBAF, Witten/Herdecke University, Stockumer Strasse 12, 58453, Witten, Germany
| | - Wing-Kee Lee
- Physiology and Pathophysiology of Cells and Membranes, Medical School EWL, Bielefeld University, R.1 B2-13, Morgenbreede 1, 33615 Bielefeld, Germany
| |
Collapse
|
3
|
Tarade D, Lee JE, Ohh M. Evolution of metazoan oxygen-sensing involved a conserved divergence of VHL affinity for HIF1α and HIF2α. Nat Commun 2019; 10:3293. [PMID: 31337753 PMCID: PMC6650433 DOI: 10.1038/s41467-019-11149-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 06/26/2019] [Indexed: 12/18/2022] Open
Abstract
Duplication of ancestral hypoxia-inducible factor (HIF)α coincided with the evolution of vertebrate species. Paralogs HIF1α and HIF2α are the most well-known factors for modulating the cellular transcriptional profile following hypoxia. However, how the processes of natural selection acted upon the coding region of these two genes to optimize the cellular response to hypoxia during evolution remains unclear. A key negative regulator of HIFα is von Hippel-Lindau (VHL) tumour suppressor protein. Here we show that evolutionarily-relevant substitutions can modulate a secondary contact between HIF1α Met561 and VHL Phe91. Notably, HIF1α binds more tightly than HIF2α to VHL due to a conserved Met to Thr substitution observed in the vertebrate lineage. Similarly, substitution of VHL Phe91 with Tyr, as seen in invertebrate species, decreases VHL affinity for both HIF1α and HIF2α. We propose that vertebrate evolution involved a more complex hypoxia response with fine-tuned divergence of VHL affinity for HIF1α and HIF2α. Paralogs HIF1α and HIF2α are important modulators regulating cellular transcriptional profile following hypoxia. Here, the authors investigate evolutionary substitutions that fine tune the interaction between HIFα and their regulator VHL in the vertebrate and invertebrate lineages.
Collapse
Affiliation(s)
- Daniel Tarade
- Department of Laboratory Medicine & Pathobiology, University of Toronto, 1 King's College Circle, Toronto, ON, M5S 1A8, Canada
| | - Jeffrey E Lee
- Department of Laboratory Medicine & Pathobiology, University of Toronto, 1 King's College Circle, Toronto, ON, M5S 1A8, Canada
| | - Michael Ohh
- Department of Laboratory Medicine & Pathobiology, University of Toronto, 1 King's College Circle, Toronto, ON, M5S 1A8, Canada. .,Department of Biochemistry, University of Toronto, 661 University Avenue, Toronto, ON, M5G 1M1, Canada.
| |
Collapse
|
4
|
Toyooka T, Yanagiba Y, Ibuki Y, Wang RS. Trichloroethylene exposure results in the phosphorylation of histone H2AX in a human hepatic cell line through cytochrome P450 2E1-mediated oxidative stress. J Appl Toxicol 2018; 38:1224-1232. [PMID: 29722447 DOI: 10.1002/jat.3632] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 03/16/2018] [Accepted: 03/22/2018] [Indexed: 01/21/2023]
Abstract
Trichloroethylene (TCE), a chlorinated hydrocarbon, was recently reclassified as a human carcinogen by the International Agency for Research on Cancer. Genotoxic events are known to be crucial steps in the initiation of cancer. The genotoxic properties of TCE have been examined in many studies using a standard battery of genotoxicity tests both in vitro and in vivo. However, consistent results have not been obtained, and studies investigating the mechanism behind the genotoxicity of this compound are lacking. In the present study, we examined the genotoxicity of TCE by assessing phosphorylated histone H2AX (γ-H2AX), a new sensitive and reliable marker of DNA damage, in WRL-68 cells, cultured human hepatocytes and mouse livers. Our results showed that TCE exposure results in the generation of γ-H2AX, both in vitro and in vivo. By investigating the in vitro mechanism, we found that TCE increases the levels of intracellular reactive oxygen species (ROS) and that this increase in ROS levels is attenuated in the presence of disulfiram, a specific cytochrome P450 2E1 (CYP2E1) inhibitor. Furthermore, γ-H2AX induced by TCE was also attenuated by CYP2E1 inhibitors and the antioxidant N-acetylcysteine. These results suggested that ROS, produced via cytochrome P450 2E1-mediated metabolic processing, is a major causal factor for γ-H2AX generation upon exposure to TCE.
Collapse
Affiliation(s)
- Tatsushi Toyooka
- Industrial Toxicology and Health Effects Research Group, National Institute of Occupational Safety and Health, Japan
| | - Yukie Yanagiba
- Industrial Toxicology and Health Effects Research Group, National Institute of Occupational Safety and Health, Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Japan
| | - Rui-Sheng Wang
- Industrial Toxicology and Health Effects Research Group, National Institute of Occupational Safety and Health, Japan
| |
Collapse
|
5
|
Abstract
Many potentially toxic electrophilic xenobiotics and some endogenous compounds are detoxified by conversion to the corresponding glutathione S-conjugate, which is metabolized to the N-acetylcysteine S-conjugate (mercapturate) and excreted. Some mercapturate pathway components, however, are toxic. Bioactivation (toxification) may occur when the glutathione S-conjugate (or mercapturate) is converted to a cysteine S-conjugate that undergoes a β-lyase reaction. If the sulfhydryl-containing fragment produced in this reaction is reactive, toxicity may ensue. Some drugs and halogenated workplace/environmental contaminants are bioactivated by this mechanism. On the other hand, cysteine S-conjugate β-lyases occur in nature as a means of generating some biologically useful sulfhydryl-containing compounds.
Collapse
|
6
|
De La Rosa VY, Asfaha J, Fasullo M, Loguinov A, Li P, Moore LE, Rothman N, Nakamura J, Swenberg JA, Scelo G, Zhang L, Smith MT, Vulpe CD. Editor's Highlight: High-Throughput Functional Genomics Identifies Modulators of TCE Metabolite Genotoxicity and Candidate Susceptibility Genes. Toxicol Sci 2017; 160:111-120. [PMID: 28973557 PMCID: PMC5837773 DOI: 10.1093/toxsci/kfx159] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Trichloroethylene (TCE), an industrial chemical and environmental contaminant, is a human carcinogen. Reactive metabolites are implicated in renal carcinogenesis associated with TCE exposure, yet the toxicity mechanisms of these metabolites and their contribution to cancer and other adverse effects remain unclear. We employed an integrated functional genomics approach that combined functional profiling studies in yeast and avian DT40 cell models to provide new insights into the specific mechanisms contributing to toxicity associated with TCE metabolites. Genome-wide profiling studies in yeast identified the error-prone translesion synthesis (TLS) pathway as an import mechanism in response to TCE metabolites. The role of TLS DNA repair was further confirmed by functional profiling in DT40 avian cell lines, but also revealed that TLS and homologous recombination DNA repair likely play competing roles in cellular susceptibility to TCE metabolites in higher eukaryotes. These DNA repair pathways are highly conserved between yeast, DT40, and humans. We propose that in humans, mutagenic TLS is favored over homologous recombination repair in response to TCE metabolites. The results of these studies contribute to the body of evidence supporting a mutagenic mode of action for TCE-induced renal carcinogenesis mediated by reactive metabolites in humans. Our approach illustrates the potential for high-throughput in vitro functional profiling in yeast to elucidate toxicity pathways (molecular initiating events, key events) and candidate susceptibility genes for focused study.
Collapse
Affiliation(s)
- Vanessa Y. De La Rosa
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California 94720
| | - Jonathan Asfaha
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California 94720
| | - Michael Fasullo
- Colleges of Nanoscale Science and Engineering, State University of New York Polytechnic Institute, Albany, New York 12205
| | - Alex Loguinov
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California 94720
| | - Peng Li
- International Agency for Research on Cancer (IARC), Lyon, France
| | - Lee E. Moore
- Division of Cancer Epidemiology and Genetics, Department of Health and Human Services, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Nathaniel Rothman
- Division of Cancer Epidemiology and Genetics, Department of Health and Human Services, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Jun Nakamura
- Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina
| | | | - Ghislaine Scelo
- International Agency for Research on Cancer (IARC), Lyon, France
| | - Luoping Zhang
- Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, California 94720
| | - Martyn T. Smith
- Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, California 94720
| | - Chris D. Vulpe
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California 94720
| |
Collapse
|
7
|
Alosi D, Bisgaard ML, Hemmingsen SN, Krogh LN, Mikkelsen HB, Binderup MLM. Management of Gene Variants of Unknown Significance: Analysis Method and Risk Assessment of the VHL Mutation p.P81S (c.241C>T). Curr Genomics 2017; 18:93-103. [PMID: 28503092 PMCID: PMC5321774 DOI: 10.2174/1389202917666160805153221] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Revised: 07/19/2016] [Accepted: 07/28/2016] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Evaluation of the pathogenicity of a gene variant of unknown significance (VUS) is crucial for molecular diagnosis and genetic counseling, but can be challenging. This is especially so in phenotypically variable diseases, such as von Hippel-Lindau disease (vHL). vHL is caused by germline mutations in the VHL gene, which predispose to the development of multiple tumors such as central nervous system hemangioblastomas and renal cell carcinoma (RCC). OBJECTIVE We propose a method for the evaluation of VUS pathogenicity through our experience with the VHL missense mutation c.241C>T (p.P81S). METHOD 1) Clinical evaluation of known variant carriers: We evaluated a family of five VHL p.P81S carriers, as well as the clinical characteristics of all the p.P81S carriers reported in the literature; 2) Evaluation of tumor tissue via genetic analysis, histology, and immunohistochemistry (IHC); 3) Assessment of the variant's impact on protein structure and function, using multiple databases, in silico algorithms, and reports of functional studies. RESULTS Only one family member had clinical signs of vHL with early-onset RCC. IHC analysis showed no VHL protein expressed in the tumor, consistent with biallelic VHL inactivation. The majority of in silico algorithms reported p.P81S as possibly pathogenic in relation to vHL or RCC, but there were discrepancies. Functional studies suggest that p.P81S impairs the VHL protein's function. CONCLUSION The VHL p.P81S mutation is most likely a low-penetrant pathogenic variant predisposing to RCC development. We suggest the above-mentioned method for VUS evaluation with use of different methods, especially a variety of in silico methods and tumor tissue analysis.
Collapse
Affiliation(s)
- Daniela Alosi
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Marie Luise Bisgaard
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Sophie Nowak Hemmingsen
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | | | - Hanne Birte Mikkelsen
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | | |
Collapse
|
8
|
Lash LH, Chiu WA, Guyton KZ, Rusyn I. Trichloroethylene biotransformation and its role in mutagenicity, carcinogenicity and target organ toxicity. MUTATION RESEARCH. REVIEWS IN MUTATION RESEARCH 2014; 762:22-36. [PMID: 25484616 PMCID: PMC4254735 DOI: 10.1016/j.mrrev.2014.04.003] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Metabolism is critical for the mutagenicity, carcinogenicity, and other adverse health effects of trichloroethylene (TCE). Despite the relatively small size and simple chemical structure of TCE, its metabolism is quite complex, yielding multiple intermediates and end-products. Experimental animal and human data indicate that TCE metabolism occurs through two major pathways: cytochrome P450 (CYP)-dependent oxidation and glutathione (GSH) conjugation catalyzed by GSH S-transferases (GSTs). Herein we review recent data characterizing TCE processing and flux through these pathways. We describe the catalytic enzymes, their regulation and tissue localization, as well as the evidence for transport and inter-organ processing of metabolites. We address the chemical reactivity of TCE metabolites, highlighting data on mutagenicity of these end-products. Identification in urine of key metabolites, particularly trichloroacetate (TCA), dichloroacetate (DCA), trichloroethanol and its glucuronide (TCOH and TCOG), and N-acetyl-S-(1,2-dichlorovinyl)-L-cysteine (NAcDCVC), in exposed humans and other species (mostly rats and mice) demonstrates function of the two metabolic pathways in vivo. The CYP pathway primarily yields chemically stable end-products. However, the GST pathway conjugate S-(1,2-dichlorovinyl)glutathione (DCVG) is further processed to multiple highly reactive species that are known to be mutagenic, especially in kidney where in situ metabolism occurs. TCE metabolism is highly variable across sexes, species, tissues and individuals. Genetic polymorphisms in several of the key enzymes metabolizing TCE and its intermediates contribute to variability in metabolic profiles and rates. In all, the evidence characterizing the complex metabolism of TCE can inform predictions of adverse responses including mutagenesis, carcinogenesis, and acute and chronic organ-specific toxicity.
Collapse
Affiliation(s)
- Lawrence H. Lash
- Department of Pharmacology, Wayne State University School of Medicine, 540 East Canfield Avenue, Detroit, MI, 48201 USA
| | - Weihsueh A. Chiu
- U.S. Environmental Protection Agency, 1200 Pennsylvania Avenue, NW, Washington, DC, 20460 USA; Chiu.Weihsueh@.epa.gov;
| | - Kathryn Z. Guyton
- U.S. Environmental Protection Agency, 1200 Pennsylvania Avenue, NW, Washington, DC, 20460 USA; Chiu.Weihsueh@.epa.gov;
| | - Ivan Rusyn
- Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC 27599 USA;
| |
Collapse
|
9
|
Neckers L, Ricketts CJ, Marston Linehan W. New insights into von Hippel-Lindau function highlighted by investigation of the trichloroethylene-induced p.P81S hotspot mutation. J Natl Cancer Inst 2013; 105:1339-40. [PMID: 23990664 DOI: 10.1093/jnci/djt240] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Affiliation(s)
- Len Neckers
- Affiliations of authors: Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD (LN, CJR, WML)
| | | | | |
Collapse
|
10
|
Desimone MC, Rathmell WK, Threadgill DW. Pleiotropic effects of the trichloroethylene-associated P81S VHL mutation on metabolism, apoptosis, and ATM-mediated DNA damage response. J Natl Cancer Inst 2013; 105:1355-64. [PMID: 23990666 PMCID: PMC3776265 DOI: 10.1093/jnci/djt226] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND The risk relevance of the P81S von Hippel-Lindau (VHL) gene hotspot mutation identified in clear cell renal cell carcinoma from individuals exposed occupationally to trichloroethylene (TCE) is not known. VHL mutations in hereditary VHL syndrome strongly correlate with phenotypic associations, but specific sporadic mutations in VHL that uniquely alter its protein function may provide a selective growth advantage for somatic cells harboring these mutations. METHODS VHL deficient (Vhl (-/-) ) mouse embryonic stem cells were generated that stably express wild-type, P81S, or R167Q human VHL protein. Under hypoxic conditions, cell lines were examined for hypoxia-inducible transcription factor family (HIF) stabilization and E3-ubiquitin ligase complex interactions. In vivo, teratomas were examined for tumor size, proliferation, apoptosis, and immunohistochemistry and subjected to gene expression analysis. Wild-type, R167Q, and P81S VHL-expressing teratomas were also exposed to 5 Gy ionizing radiation to quantify apoptotic response. Proliferation and apoptosis and teratoma growth were analyzed by either Student t test or analysis of variance with Bonferroni correction. All statistical tests were two-sided. RESULTS The P81S VHL mutation produces deregulation of HIF factors in cell culture but exhibits a growth advantage in the tumor microenvironment, in part because of suppression of apoptosis (P81S mean = 0.9%, 95% confidence interval = 0.6 to 1.2%; WT mean = 7.6%; 95% confidence interval = 6.4 to 8.8%; P < .001) coupled with sustained proliferation. Transcriptional analysis of P81S teratomas revealed the induction of metabolic pathways, antiapoptotic genes, and global suppression of key DNA damage response genes not observed in VHL wild-type or R167Q mutants. In vivo irradiation exposure showed that P81S mutant is resistant to ionizing radiation-induced apoptosis. CONCLUSIONS The TCE-associated P81S VHL mutation can initiate a unique adaptive response required for selective tumor growth through pleiotropic effects on metabolic diversification, apoptosis suppression, and alteration of the DNA damage response.
Collapse
Affiliation(s)
- Michelle C Desimone
- Affiliations of authors: Department of Genetics, North Carolina State University, Raleigh, NC (MCD, DWT); Department of Genetics (WKR) and Lineberger Cancer Center, University of North Carolina, Chapel Hill, NC (WKR, DWT)
| | | | | |
Collapse
|
11
|
Rusyn I, Chiu WA, Lash LH, Kromhout H, Hansen J, Guyton KZ. Trichloroethylene: Mechanistic, epidemiologic and other supporting evidence of carcinogenic hazard. Pharmacol Ther 2013; 141:55-68. [PMID: 23973663 DOI: 10.1016/j.pharmthera.2013.08.004] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 07/31/2013] [Indexed: 02/09/2023]
Abstract
The chlorinated solvent trichloroethylene (TCE) is a ubiquitous environmental pollutant. The carcinogenic hazard of TCE was the subject of a 2012 evaluation by a Working Group of the International Agency for Research on Cancer (IARC). Information on exposures, relevant data from epidemiologic studies, bioassays in experimental animals, and toxicity and mechanism of action studies was used to conclude that TCE is carcinogenic to humans (Group 1). This article summarizes the key evidence forming the scientific bases for the IARC classification. Exposure to TCE from environmental sources (including hazardous waste sites and contaminated water) is common throughout the world. While workplace use of TCE has been declining, occupational exposures remain of concern, especially in developing countries. The strongest human evidence is from studies of occupational TCE exposure and kidney cancer. Positive, although less consistent, associations were reported for liver cancer and non-Hodgkin lymphoma. TCE is carcinogenic at multiple sites in multiple species and strains of experimental animals. The mechanistic evidence includes extensive data on the toxicokinetics and genotoxicity of TCE and its metabolites. Together, available evidence provided a cohesive database supporting the human cancer hazard of TCE, particularly in the kidney. For other target sites of carcinogenicity, mechanistic and other data were found to be more limited. Important sources of susceptibility to TCE toxicity and carcinogenicity were also reviewed by the Working Group. In all, consideration of the multiple evidence streams presented herein informed the IARC conclusions regarding the carcinogenicity of TCE.
Collapse
Affiliation(s)
- Ivan Rusyn
- University of North Carolina, Chapel Hill, NC, USA.
| | | | | | | | - Johnni Hansen
- Danish Cancer Society Research Center, Copenhagen, Denmark
| | | |
Collapse
|
12
|
Chiu WA, Jinot J, Scott CS, Makris SL, Cooper GS, Dzubow RC, Bale AS, Evans MV, Guyton KZ, Keshava N, Lipscomb JC, Barone S, Fox JF, Gwinn MR, Schaum J, Caldwell JC. Human health effects of trichloroethylene: key findings and scientific issues. ENVIRONMENTAL HEALTH PERSPECTIVES 2013; 121:303-11. [PMID: 23249866 PMCID: PMC3621199 DOI: 10.1289/ehp.1205879] [Citation(s) in RCA: 150] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 12/17/2012] [Indexed: 05/19/2023]
Abstract
BACKGROUND In support of the Integrated Risk Information System (IRIS), the U.S. Environmental Protection Agency (EPA) completed a toxicological review of trichloroethylene (TCE) in September 2011, which was the result of an effort spanning > 20 years. OBJECTIVES We summarized the key findings and scientific issues regarding the human health effects of TCE in the U.S. EPA's toxicological review. METHODS In this assessment we synthesized and characterized thousands of epidemiologic, experimental animal, and mechanistic studies, and addressed several key scientific issues through modeling of TCE toxicokinetics, meta-analyses of epidemiologic studies, and analyses of mechanistic data. DISCUSSION Toxicokinetic modeling aided in characterizing the toxicological role of the complex metabolism and multiple metabolites of TCE. Meta-analyses of the epidemiologic data strongly supported the conclusions that TCE causes kidney cancer in humans and that TCE may also cause liver cancer and non-Hodgkin lymphoma. Mechanistic analyses support a key role for mutagenicity in TCE-induced kidney carcinogenicity. Recent evidence from studies in both humans and experimental animals point to the involvement of TCE exposure in autoimmune disease and hypersensitivity. Recent avian and in vitro mechanistic studies provided biological plausibility that TCE plays a role in developmental cardiac toxicity, the subject of substantial debate due to mixed results from epidemiologic and rodent studies. CONCLUSIONS TCE is carcinogenic to humans by all routes of exposure and poses a potential human health hazard for noncancer toxicity to the central nervous system, kidney, liver, immune system, male reproductive system, and the developing embryo/fetus.
Collapse
Affiliation(s)
- Weihsueh A Chiu
- National Center for Environmental Assessment, U.S. Environmental Protection Agency (EPA), Washington, DC, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Karami S, Colt JS, Schwartz K, Davis FG, Ruterbusch JJ, Munuo SS, Wacholder S, Stewart PA, Graubard BI, Rothman N, Chow WH, Purdue MP. A case-control study of occupation/industry and renal cell carcinoma risk. BMC Cancer 2012; 12:344. [PMID: 22873580 PMCID: PMC3502582 DOI: 10.1186/1471-2407-12-344] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Accepted: 07/09/2012] [Indexed: 01/22/2023] Open
Abstract
Background The role of occupation in the etiology of renal cell carcinoma (RCC) is unclear. Here, we investigated associations between employment in specific occupations and industries and RCC, and its most common histologic subtype, clear cell RCC (ccRCC). Methods Between 2002 and 2007, a population-based case–control study of Caucasians and African Americans (1,217 cases; 1,235 controls) was conducted within the Detroit and Chicago metropolitan areas to investigate risk factors for RCC. As part of this study, occupational histories were ascertained through in-person interviews. We computed odds ratios (ORs) and 95% confidence intervals (CIs) relating occupation and industry to RCC risk using adjusted unconditional logistic regression models. Results Employment in the agricultural crop production industry for five years or more was associated with RCC (OR = 3.3 [95% CI = 1.0-11.5]) and ccRCC in particular (OR = 6.3 [95% CI = 1.7-23.3], P for trend with duration of employment = 0.0050). Similarly, RCC risk was elevated for employment of five years or longer in non-managerial agricultural and related occupations (ORRCC = 2.1 [95% CI = 1.0-4.5]; ORccRCC = 3.1 [95% CI = 1.4-6.8]). Employment in the dry-cleaning industry was also associated with elevated risk (ORRCC = 2.0 [95% CI = 0.9-4.4], P for trend = 0.093; ORccRCC = 3.0 [95% CI = 1.2-7.4], P for trend = 0.031). Suggestive elevated associations were observed for police/public safety workers, health care workers and technicians, and employment in the electronics, auto repair, and cleaning/janitorial services industries; protective associations were suggested for many white-collar jobs including computer science and administrative occupations as well employment in the business, legislative, and education industries. Conclusions Our findings provide support for an elevated risk of RCC in the agricultural and dry-cleaning industries and suggest that these associations may be stronger for the ccRCC subtype. Additional studies are needed to confirm these findings.
Collapse
Affiliation(s)
- Sara Karami
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, 6120 Executive Boulevard, MSC 7242, Bethesda, MD 20892-7242, USA.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Navai N, Wood CG. Environmental and modifiable risk factors in renal cell carcinoma. Urol Oncol 2012; 30:220-4. [PMID: 22385993 DOI: 10.1016/j.urolonc.2011.10.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Revised: 10/03/2011] [Accepted: 10/04/2011] [Indexed: 01/20/2023]
Abstract
OBJECTIVES Prevention of disease requires a firm understanding of the relevant environmental and modifiable risk factors. We present a comprehensive review of these factors in renal cell carcinoma. MATERIALS AND METHODS A literature search of the PubMed database was performed to identify clinical studies examining the relationship between environmental and modifiable factors in the development of renal cell carcinoma (terms utilized: kidney cancer; renal cell carcinoma; risk factors; environment; obesity; hypertension; trichloroethylene). An emphasis was placed on more recent studies. RESULTS Case control and large cohort studies have examined the relationship of numerous environmental and modifiable factors and the risk of renal cell carcinoma. Of particular note are dose-dependent increases in smokers, the obese, and hypertensive patients. CONCLUSIONS Environmental and modifiable risk factors contribute significantly to the risk of sporadic renal cell carcinoma. Emphasis should be placed on smoking cessation and hypertension control. Emerging evidence would suggest that dietary intake and quality impact renal cell carcinoma risk.
Collapse
Affiliation(s)
- Neema Navai
- Department of Urology, University of Texas M. D. Anderson Cancer Center, Houston, TX 77054, USA.
| | | |
Collapse
|
15
|
Ellsworth EM, Palma JF, Spence WC, Bleicher JM, Smith DM, Finkelstein SD. Mutational profiling of sporadic versus toxin-associated brain cancer formation: Initial findings using loss of heterozygosity profiling. Int J Hyg Environ Health 2012; 215:427-33. [DOI: 10.1016/j.ijheh.2011.08.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Revised: 08/22/2011] [Accepted: 08/31/2011] [Indexed: 10/17/2022]
|
16
|
Lai Y, Song M, Hakala K, Weintraub ST, Shiio Y. The interaction of the von Hippel-Lindau tumor suppressor and heterochromatin protein 1. Arch Biochem Biophys 2012; 518:103-10. [PMID: 22234250 DOI: 10.1016/j.abb.2011.12.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Revised: 12/20/2011] [Accepted: 12/23/2011] [Indexed: 10/14/2022]
Abstract
Inactivation of the von Hippel-Lindau (VHL) tumor suppressor is associated with renal carcinoma, hemangioblastoma and pheochromocytoma. The VHL protein is a component of a ubiquitin ligase complex that ubiquitinates and degrades hypoxia inducible factor-α (HIF-α). Degradation of HIF-α by VHL is proposed to suppress tumorigenesis and tumor angiogenesis. Several lines of evidence also suggest important roles for HIF-independent VHL functions in tumor suppression and other biological processes. Using GST-VHL pull-down experiment and mass spectrometry, we detected an interaction between VHL and heterochromatin protein 1 (HP1). We identified a conserved HP1-binding motif (PXVXL) in the β domain of VHL, which is disrupted in a renal carcinoma-associated P81S mutant. We show that the VHL P81S mutant displays reduced binding to HP1, yet retains the ability to interact with elongin B, elongin C, and cullin 2 and is fully capable of degrading HIF-α. We also demonstrate that HP1 increases the chromatin association of VHL. These results suggest a role for the VHL-HP1 interaction in VHL chromatin targeting.
Collapse
Affiliation(s)
- Yanlai Lai
- Greehey Children's Cancer Research Institute, The University of Texas Health Science Center, San Antonio, TX 78229-3900, USA
| | | | | | | | | |
Collapse
|
17
|
Abstract
Renal cell cancer (RCC) is increasingly diagnosed at an early stage in many countries, which likely contributes to the recent leveling of RCC mortality in the United States and many European countries. However, over all stages nearly 50% of the patients die within 5 years after diagnosis. Smoking and obesity may account for approximately 40% of all incidental cases in high-risk countries. Besides obesity, rising prevalence of hypertension may play a growing role. Several other occupational and lifestyle factors may also affect the risk of RCC. Genetic variations may be an important factor in the differing incidence among populations.
Collapse
Affiliation(s)
- Eunyoung Cho
- Channing Laboratory, Department of Medicine, Harvard Medical School and Brigham and Women's Hospital, 181 Longwood Avenue, Boston, MA 02115, USA.
| | | | | |
Collapse
|
18
|
Jollow DJ, Bruckner JV, McMillan DC, Fisher JW, Hoel DG, Mohr LC. Trichloroethylene risk assessment: a review and commentary. Crit Rev Toxicol 2010; 39:782-97. [PMID: 19852561 DOI: 10.3109/10408440903222177] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Trichloroethylene (TCE) is a widespread environmental contaminant that is carcinogenic when given in high, chronic doses to certain strains of mice and rats. The capacity of TCE to cause cancer in humans is less clear. The current maximum contaminant level (MCL) of 5 ppb (microg/L) is based on an US Environment Protection Agency (USEPA) policy decision rather than the underlying science. In view of major advances in understanding the etiology and mechanisms of chemically induced cancer, USEPA began in the late 1990s to revise its guidelines for cancer risk assessment. TCE was chosen as the pilot chemical. The USEPA (2005) final guidelines emphasized a "weight-of-evidence" approach with consideration of dose-response relationships, modes of action, and metabolic/toxicokinetic processes. Where adequate data are available to support reversible binding of the carcinogenic moiety to biological receptors as the initiating event (i.e., a threshold exists), a nonlinear approach is to be used. Otherwise, the default assumption of a linear (i.e., nonthreshold) dose-response is utilized. When validated physiologically based pharmacokinetic (PBPK) models are available, they are to be used to predict internal dosimetry as the basis for species and dose extrapolations. The present article reviews pertinent literature and discusses areas where research may resolve some outstanding issues and facilitate the reassessment process. Key research needs are proposed, including role of dichloroacetic acid (DCA) in TCE-induced liver tumorigenesis in humans; extension of current PBPK models to predict target organ deposition of trichloroacetic acid (TCA) and DCA in humans ingesting TCE in drinking water; use of human hepatocytes to ascertain metabolic rate constants for use in PBPK models that incorporate variability in metabolism of TCE by potentially sensitive subpopulations; measurement of the efficiency of first-pass elimination of trace levels of TCE in drinking water; and assessment of exogenous factors' (e.g., alcohol, drugs) ability to alter metabolic activation and risks at such low-level exposure.
Collapse
Affiliation(s)
- David J Jollow
- Department of Cell and Molecular Pharmacology, Medical University of South Carolina, Charleston, South Carolina 29425, USA
| | | | | | | | | | | |
Collapse
|
19
|
Abstract
Many potentially toxic electrophiles react with glutathione to form glutathione S-conjugates in reactions catalyzed or enhanced by glutathione S-transferases. The glutathione S-conjugate is sequentially converted to the cysteinylglycine-, cysteine- and N-acetyl-cysteine S-conjugate (mercapturate). The mercapturate is generally more polar and water soluble than the parent electrophile and is readily excreted. Excretion of the mercapturate represents a detoxication mechanism. Some endogenous compounds, such as leukotrienes, prostaglandin (PG) A2, 15-deoxy-Δ12,14-PGJ2, and hydroxynonenal can also be metabolized to mercapturates and excreted. On occasion, however, formation of glutathione S- and cysteine S-conjugates are bioactivation events as the metabolites are mutagenic and/or cytotoxic. When the cysteine S-conjugate contains a strong electron-withdrawing group attached at the sulfur, it may be converted by cysteine S-conjugate β-lyases to pyruvate, ammonium and the original electrophile modified to contain an –SH group. If this modified electrophile is highly reactive then the enzymes of the mercapturate pathway together with the cysteine S-conjugate β-lyases constitute a bioactivation pathway. Some endogenous halogenated environmental contaminants and drugs are bioactivated by this mechanism. Recent studies suggest that coupling of enzymes of the mercapturate pathway to cysteine S-conjugate β-lyases may be more common in nature and more widespread in the metabolism of electrophilic xenobiotics than previously realized.
Collapse
|
20
|
Young AC, Craven RA, Cohen D, Taylor C, Booth C, Harnden P, Cairns DA, Astuti D, Gregory W, Maher ER, Knowles MA, Joyce A, Selby PJ, Banks RE. Analysis of VHL Gene Alterations and their Relationship to Clinical Parameters in Sporadic Conventional Renal Cell Carcinoma. Clin Cancer Res 2009; 15:7582-7592. [PMID: 19996202 DOI: 10.1158/1078-0432.ccr-09-2131] [Citation(s) in RCA: 136] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE: This study aimed to carry out a comprehensive analysis of genetic and epigenetic changes of the von Hippel Lindau (VHL) gene in patients with conventional (clear cell) renal cell carcinoma and to determine their significance relative to clinicopathologic characteristics and outcome. EXPERIMENTAL DESIGN: The VHL status in 86 conventional renal cell carcinomas was determined by mutation detection, loss of heterozygosity (LOH), and promoter methylation analysis, extending our original cohort to a total of 177 patients. Data were analyzed to investigate potential relationships between VHL changes, clinical parameters, and outcome. RESULTS: LOH was found in 89.2%, mutation in 74.6%, and methylation in 31.3% of evaluable tumors; evidence of biallelic inactivation (LOH and mutation or methylation alone) was found in 86.0% whereas no involvement of VHL was found in only 3.4% of samples. Several associations were suggested, including those between LOH and grade, nodal status and necrosis, mutation and sex, and methylation and grade. Biallelic inactivation may be associated with better overall survival compared with patients with no VHL involvement, although small sample numbers in the latter group severely limit this analysis, which requires independent confirmation. CONCLUSIONS: This study reports one of the highest proportions of conventional renal cell carcinoma with VHL changes, and suggests possible relationships between VHL status and clinical variables. The data suggest that VHL defects may define conventional renal cell carcinomas but the clinical significance of specific VHL alterations will only be clarified by the determination of their biological effect at the protein level rather than through genetic or epigenetic analysis alone. (Clin Cancer Res 2009;15(24):7582-92).
Collapse
Affiliation(s)
- Alison C Young
- Authors' Affiliations: Cancer Research UK Clinical Centre, Cancer Research UK Mutation Detection Facility, and Pyrah Department of Urology, St James's University Hospital, and Clinical Trials Research Unit, University of Leeds, Leeds, United Kingdom; and Cancer Research UK Renal Molecular Oncology Group, University of Birmingham, Edgbaston, United Kingdom
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Wartenberg D. Environmental factors in cancer: trichloroethylene and related solvents: science, regulation, and cancer prevention. REVIEWS ON ENVIRONMENTAL HEALTH 2009; 24:297-302. [PMID: 20384037 PMCID: PMC4027958 DOI: 10.1515/reveh.2009.24.4.297] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
In summary, I have used the case of TCE exposure as an example of: (1) The importance of population-based research to identify and characterize possible environmental risk factors for cancer, and the need for a greater emphasis and proportional increase in public funding of research on prevention as compared to treatment. We need to understand these risks better, and use this information to drive effective public health prevention actions. (2) The imposition of strong restrictions on requests by bona fide researchers for access to data as a barrier to research that could be used to help resolve some of the most controversial issues in TCE epidemiology, in particular, and environmental risks in general, especially access to individual level data including data of event and location of residence. Researchers need ready access these data to more accurately characterize environmental exposures, diseases and their possible associations, and to help develop more effective public health preventive actions, although they should also protect confidentiality. (3) The need for more accurate and comprehensive biomarkers of exposure and disease to better assess possible associations between environmental and occupational exposures and disease; (4) The role of non-scientific concerns in limiting regulatory and advisory agencies in the reevaluation of their positions relative to preventing or lowering allowable exposures to TCE, in light of the growing body of evidence on the possible carcinogenicity of a compound still widely in use, to which many workers, and substantial segments of the general public, are exposed.
Collapse
Affiliation(s)
- Daniel Wartenberg
- Division of Environmental Epidemiology, Department of Environmental and Occupational Medicine, University of Medicine and Dentistry of New Jersey Robert Wood Johnson Medical School and The Cancer Institute of New Jersey 170 Frelinghuysen Road, Room 234A, Piscataway, NJ 08854, USA
| |
Collapse
|
22
|
Lipworth L, Tarone RE, Lund L, McLaughlin JK. Epidemiologic characteristics and risk factors for renal cell cancer. Clin Epidemiol 2009; 1:33-43. [PMID: 20865085 PMCID: PMC2943168 DOI: 10.2147/clep.s4759] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Incidence rates of renal cell cancer, which accounts for 85% of kidney cancers, have been rising in the United States and in most European countries for several decades. Family history is associated with a two- to four-fold increase in risk, but the major forms of inherited predisposition together account for less than 4% of renal cell cancers. Cigarette smoking, obesity, and hypertension are the most consistently established risk factors. Analgesics have not been convincingly linked with renal cell cancer risk. A reduced risk of renal cell cancer among statin users has been hypothesized but has not been adequately studied. A possible protective effect of fruit and vegetable consumption is the only moderately consistently reported dietary finding, and, with the exception of a positive association with parity, evidence for a role of hormonal or reproductive factors in the etiology of renal cell cancer in humans is limited. A recent hypothesis that moderate levels of alcohol consumption may be protective for renal cell cancer is not strongly supported by epidemiologic results, which are inconsistent with respect to the categories of alcohol consumption and the amount of alcohol intake reportedly associated with decreased risk. For occupational factors, the weight of the evidence does not provide consistent support for the hypotheses that renal cell cancer may be caused by asbestos, gasoline, or trichloroethylene exposure. The established determinants of renal cell cancer, cigarette smoking, obesity, and hypertension, account for less than half of these cancers. Novel epidemiologic approaches, including evaluation of gene–environment interactions and epigenetic mechanisms of inherited and acquired increased risk, are needed to explain the increasing incidence of renal cell cancer.
Collapse
Affiliation(s)
- Loren Lipworth
- International Epidemiology Institute, Rockville, MD, USA
| | | | | | | |
Collapse
|
23
|
Knauth K, Cartwright E, Freund S, Bycroft M, Buchberger A. VHL mutations linked to type 2C von Hippel-Lindau disease cause extensive structural perturbations in pVHL. J Biol Chem 2009; 284:10514-22. [PMID: 19228690 PMCID: PMC2667738 DOI: 10.1074/jbc.m809056200] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2008] [Indexed: 11/06/2022] Open
Abstract
pVHL (von Hippel-Lindau tumor suppressor protein) is the substrate recognition subunit of the CBC(VHL) ubiquitin ligase complex promoting the degradation of hypoxia-inducible factor subunits, HIF-1/2alpha. Mutational inactivation of pVHL causes the hereditary von Hippel-Lindau tumor syndrome, which predisposes affected individuals to hemangioblastomas, renal cell carcinomas, and pheochromocytomas. Whereas the development of hemangioblastomas and renal cell carcinomas has been attributed to impaired HIF-1/2alpha down-regulation by pVHL mutant proteins, the molecular defects underlying the development of pheochromocytomas are still unknown. Here, we present a detailed biochemical analysis of pVHL mutant proteins linked to type 2C (pheochromocytoma only) von Hippel-Lindau disease. Type 2C-associated mutations caused extensive structural perturbations of pVHL, as revealed by the reduced stability, increased proteolytic susceptibility, and dramatically altered NMR spectrum of recombinant, mutant pVHL-ElonginC-ElonginB complexes in vitro. In human cell lines, type 2C-linked mutations destabilized the CBC(VHL) ubiquitin ligase complex and resulted in reduced cellular pVHL levels. Together, our data reveal unexpectedly strong structural defects of type 2C-associated pVHL mutant proteins that are likely to affect both HIF-1/2alpha-related and -unrelated pVHL functions in the pathogenesis of pheochromocytomas.
Collapse
Affiliation(s)
- Katja Knauth
- Department of Molecular Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | | | | | | | | |
Collapse
|
24
|
Shiao YH. Genetic signature for human risk assessment: lessons from trichloroethylene. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2009; 50:68-77. [PMID: 19031419 PMCID: PMC2630226 DOI: 10.1002/em.20432] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Trichloroethylene (TCE), an organic solvent commonly used for metal degreasing and as a chemical additive, is a significant environmental contaminant that poses health concerns in humans. The US Environmental Protection Agency (EPA) is currently revising the 2001 TCE human risk assessment draft. The next draft is expected to be ready in 2008. TCE metabolites are detectable in humans and carry varying potencies for induction of cancers in animals. Genomic mechanisms have been explored in animals and humans to link TCE to carcinogenesis. DNA analysis provides an opportunity for detection of unique genetic alterations representing a signature of TCE exposure. These alterations can arise from genotoxic and nongenotoxic pathways at multiple points throughout tumorigenesis. Although fixation of alterations may require several stages of selection and modification, the spectra can be specific to TCE. Only a fraction of these alterations eventually lead to tumor formation and some contribute to tumor progression. Genetic events in two major TCE target organs are reviewed, including the VHL gene in kidney, and the Ras gene and genome-wide hypomethylation in liver. Attempts to identify a genetic signature of TCE exposure are challenged by inconsistent findings, lack of evidence of promutagenic lesions, biological relevance of specific genomic changes, and likelihood of coexposures. For human risk assessment, genome-wide screening is useful and is possible with the development of new DNA-sequencing technologies. Genetic screening for preneoplastic and tumor tissues from high-risk population is proposed to exclude the noise of passenger mutations and genetic polymorphisms.
Collapse
Affiliation(s)
- Yih-Horng Shiao
- Laboratory of Comparative Carcinogenesis, National Cancer Institute at Frederick, Frederick, Maryland 21702, USA.
| |
Collapse
|
25
|
Liu J, Huang H, Xing X, Xi R, Zhuang Z, Yuan J, Yang F, Zhao J. Comparative proteomic analysis on human L-02 liver cells treated with varying concentrations of trichloroethylene. Toxicol Ind Health 2008; 23:91-101. [PMID: 18203561 DOI: 10.1177/0748233707078223] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
To determine the differential proteomic expressions in human L-02 liver cells induced by varying concentrations of trichloroethylene (TCE), comparative proteomic analysis was performed on human L-02 liver cells which were treated with varying concentrations of TCE. According to the result of MTT test, we designed four different groups, in which the cells were treated with 0 microM (control group), 3, 10 or 40 microM TCE for 24 h, respectively. Comparative analysis of approximately 800 spots resolved by two-dimensional gel electrophoresis (2DE) in the soluble proteomes of L-02 cells from the four different groups resulted in 10 differential proteins. To identify the differential spots, matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) was carried out; if the results from the tool were insufficient, tandem MS (MALDI-TOF-TOF-MS) was then performed. The raw data of peptide mass fingerprints (PMFs) and MS/MS spectra were searched against the IPI human data base for exact matches. Then western blot was employed to verify the result of proteomic analysis, the following result confirmed that the results of proteomic analysis were reliable. These results might provide an insight into the underlying mechanism of TCE intoxication and find biological markers for diagnosis and therapy of TCE-induced diseases.
Collapse
Affiliation(s)
- Jianjun Liu
- Shenzhen Center for Disease Control and Prevention, Shenzhen 518020, Guangdong, PR. China
| | | | | | | | | | | | | | | |
Collapse
|
26
|
Baldewijns MML, van Vlodrop IJH, Schouten LJ, Soetekouw PMMB, de Bruïne AP, van Engeland M. Genetics and epigenetics of renal cell cancer. Biochim Biophys Acta Rev Cancer 2007; 1785:133-55. [PMID: 18187049 DOI: 10.1016/j.bbcan.2007.12.002] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2007] [Revised: 12/04/2007] [Accepted: 12/09/2007] [Indexed: 12/31/2022]
Abstract
Renal cell carcinoma (RCC) is not a single disease, but comprises a group of tumors of renal epithelial origin, each with a different histology, displaying a different clinical course and caused by different genetic alterations. Since cure rates are inversely associated with stage and response to the available treatment regimes is limited to a subgroup of patients, diagnostic methods facilitating early detection and new therapeutic modalities are necessary. Increased knowledge of the underlying pathophysiology of RCC has resulted in the identification of genetic alterations involved in renal cell cancer carcinogenesis. Promising agents to target these pathways, especially the angiogenesis pathway, are being developed, some of which are already standard of care. In addition to genetics, knowledge on epigenetics in the process of renal tumorigenesis has been significantly increased in the last decades. Epigenetics will play an increasing role in the development of new therapeutic modalities and may deliver new prognostic and early diagnostic markers. In this review we discuss the background of RCC and the clinical applications of RCC genetics and epigenetics.
Collapse
Affiliation(s)
- Marcella M L Baldewijns
- Department of Pathology, GROW - School for Oncology and Developmental Biology, Maastricht University, Maastricht, The Netherlands
| | | | | | | | | | | |
Collapse
|
27
|
van Dijk BAC, Schouten LJ, Oosterwijk E, Hulsbergen-van de Kaa CA, Kiemeney LALM, Goldbohm RA, Schalken JA, van den Brandt PA. Carotenoid and vitamin intake, von Hippel-Lindau gene mutations and sporadic renal cell carcinoma. Cancer Causes Control 2007; 19:125-34. [PMID: 17992578 DOI: 10.1007/s10552-007-9078-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2007] [Accepted: 10/04/2007] [Indexed: 11/27/2022]
Abstract
OBJECTIVE We investigated whether dietary carotenoid and vitamin intake and supplemental vitamin use were inversely associated with RCC risk and with Von Hippel-Lindau (VHL)-gene mutations in clear-cell renal cell carcinoma (RCC). METHODS The Netherlands Cohort Study on diet and cancer (NLCS) includes 120,852 persons, who completed a self-administered food-frequency questionnaire in 1986. After 11.3 years of follow-up, 284 cases and a random sample of 4,095 persons (subcohort) with complete data were included in multivariable analyses using a case-cohort approach. VHL gene mutational analysis was complete for 225 cases. Rate ratios and corresponding 95% confidence intervals were estimated using Cox proportional hazard models, while adjusting for age, sex, smoking, body mass index, and a history of hypertension. RESULTS We observed no association for dietary carotenoid and vitamin intake and RCC risk, and a somewhat increased risk with supplemental vitamin E, AD, and multivitamin use. Results were suggestive of higher RRs for alpha-carotene, beta-cryptoxanthin, folate, and supplemental vitamin C and multivitamin intake for wildtype VHL tumors compared to VHL-mutated tumors. CONCLUSIONS There was no association of carotenoid, vitamin or supplemental vitamin intake and RCC risk. These associations should be investigated by others to confirm the current observations.
Collapse
Affiliation(s)
- Boukje A C van Dijk
- Department of Epidemiology, NUTRIM, Maastricht University, Maastricht, The Netherlands.
| | | | | | | | | | | | | | | |
Collapse
|
28
|
Wiesenhütter B, Selinski S, Golka K, Brüning T, Bolt HM. Re-assessment of the influence of polymorphisms of phase-II metabolic enzymes on renal cell cancer risk of trichloroethylene-exposed workers. Int Arch Occup Environ Health 2007; 81:247-51. [PMID: 17479278 DOI: 10.1007/s00420-007-0200-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2006] [Accepted: 04/17/2007] [Indexed: 10/23/2022]
Abstract
PROBLEM Individual differences in susceptibility to trichloroethylene-induced nephrocarcinogenicity may be conferred by genetic polymorphisms of glutathione S-transferases (GST), because enzymes of this group are pivotal for the metabolic activation of trichloroethylene. Because of a potential involvement of N-acetylation in the detoxication of reactive trichloroethylene metabolite(s) to N-acetyl-cysteine derivatives, polymorphisms of the NAT2 gene may also be relevant. METHODS The primary collective used for a re-investigation of these questions was that of a hospital-based case-control study by Brüning et al. (Am J Ind Med 43:274-285, 2003) of 134 renal cell cancer cases (20 cases exposed to trichloroethylene) and 401 matched controls. Genetic polymorphisms of GSTT1, GSTM1, GSTP1 and NAT2 were studied. Additional control collectives of non-diseased persons were used for comparison of allele frequencies. RESULTS No genetic influences on the development of renal cancer due to trichloroethylene were apparent, related to the deletion polymorphisms of GSTT1 and GSTM1, as well as to the NAT2 rapid/slow acetylator states. However, renal cell cancer cases displayed a somewhat higher proportion of the homozygous GSTP1 313A wild type (GSTP1*A), although this was not statistically significant (chi(2) test: P=0.1071, when using only the original controls of Brüning et al. (2003); P=0.0781 with inclusion of the additional controls). CONCLUSION The re-investigation does not confirm the working hypothesis of an influence of the deletion polymorphisms of the glutathione S-transferases GSTT1 and GSTM1 on renal cell cancer development due to high occupational exposures to trichloroethylene.
Collapse
Affiliation(s)
- Bernd Wiesenhütter
- Institut für Arbeitsphysiologie an der Universität Dortmund, Ardeystr. 67, 44139 Dortmund, Germany
| | | | | | | | | |
Collapse
|
29
|
Abstract
Based on toxicology, metabolism, animal studies, and human studies, occupational exposure to chlorinated aliphatic solvents (methanes, ethanes, and ethenes) has been associated with numerous adverse health effects, including central nervous system, reproductive, liver, and kidney toxicity, and carcinogenicity. However, many of these solvents remain in active, large-volume use. This article reviews the recent occupational epidemiology literature on the most widely used solvents, methylene chloride, chloroform, trichloroethylene, and tetrachloroethylene, and discusses other chlorinated aliphatics. The impact of studies to date has been lessened because of small study size, inability to control for confounding factors, particularly smoking and mixed occupational exposures, and the lack of evidence for a solid pathway from occupational exposure to biological evidence of exposure, to precursors of health effects, and to health effects. International differences in exposure limits may provide a "natural experiment" in the coming years if countries that have lowered exposure limits subsequently experience decreased adverse health effects among exposed workers. Such decreases could provide some evidence that higher levels of adverse health effects were associated with higher levels of solvent exposure. The definitive studies, which should be prospective biomarker studies incorporating body burden of solvents as well as markers of effect, remain to be done.
Collapse
Affiliation(s)
- Avima M Ruder
- National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Cincinnati, OH 45226, USA.
| |
Collapse
|
30
|
van Dijk BAC, Schouten LJ, Oosterwijk E, Hulsbergen-van de Kaa CA, Kiemeney LALM, Goldbohm RA, Schalken JA, van den Brandt PA. Cigarette smoking, von Hippel-Lindau gene mutations and sporadic renal cell carcinoma. Br J Cancer 2006; 95:374-7. [PMID: 16892044 PMCID: PMC2360644 DOI: 10.1038/sj.bjc.6603281] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
We investigated whether smoking is associated with mutations in the Von Hippel–Lindau (VHL) gene in 337 cases of sporadic renal cell carcinoma (RCC) among 120 852 people followed for 11.3 years; the findings suggest that smoking causes RCC independently of VHL gene mutations.
Collapse
Affiliation(s)
- B A C van Dijk
- Department of Epidemiology, NUTRIM, Maastricht University, PO Box 616, Maastricht 6200 MD, The Netherlands
| | - L J Schouten
- Department of Epidemiology, NUTRIM, Maastricht University, PO Box 616, Maastricht 6200 MD, The Netherlands
- E-mail:
| | - E Oosterwijk
- Department of Urology, Radboud University Nijmegen Medical Centre, PO Box 9101, Nijmegen 6500 HB, The Netherlands
| | - C A Hulsbergen-van de Kaa
- Department of Pathology, Radboud University Nijmegen Medical Centre, PO Box 9101, Nijmegen 6500 HB, The Netherlands
| | - L A L M Kiemeney
- Department of Urology, Radboud University Nijmegen Medical Centre, PO Box 9101, Nijmegen 6500 HB, The Netherlands
- Department of Epidemiology and Biostatistics, Radboud University Nijmegen Medical Centre, PO Box 9101, Nijmegen 6500 HB, The Netherlands
| | - R A Goldbohm
- Department of Food and Chemical Risk Analysis, TNO Nutrition and Food Research, PO Box 360, Zeist 3700 AJ, The Netherlands
| | - J A Schalken
- Department of Urology, Radboud University Nijmegen Medical Centre, PO Box 9101, Nijmegen 6500 HB, The Netherlands
| | - P A van den Brandt
- Department of Epidemiology, NUTRIM, Maastricht University, PO Box 616, Maastricht 6200 MD, The Netherlands
| |
Collapse
|
31
|
Scott CS, Chiu WA. Trichloroethylene cancer epidemiology: a consideration of select issues. ENVIRONMENTAL HEALTH PERSPECTIVES 2006; 114:1471-8. [PMID: 16966107 PMCID: PMC1570052 DOI: 10.1289/ehp.8949] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
A large body of epidemiologic evidence exists for exploring causal associations between cancer and trichloroethylene (TCE) exposure. The U.S. Environmental Protection Agency 2001 draft TCE health risk assessment concluded that epidemiologic studies, on the whole, support associations between TCE exposure and excess risk of kidney cancer, liver cancer, and lymphomas, and, to a lesser extent, cervical cancer and prostate cancer. As part of a mini-monograph on key issues in the health risk assessment of TCE, this article reviews recently published scientific literature examining cancer and TCE exposure and identifies four issues that are key to interpreting the larger body of epidemiologic evidence: a) relative sensitivity of cancer incidence and mortality data ; b) different classifications of lymphomas, including non-Hodgkin lymphoma ; c) differences in data and methods for assigning TCE exposure status ; and d) different methods employed for causal inferences, including statistical or meta-analysis approaches. The recent epidemiologic studies substantially expand the epidemiologic database, with seven new studies available on kidney cancer and somewhat fewer studies available that examine possible associations at other sites. Overall, recently published studies appear to provide further support for the kidney, liver, and lymphatic systems as targets of TCE toxicity, suggesting, as do previous studies, modestly elevated (typically 1.5-2.0) site-specific relative risks, given exposure conditions in these studies. However, a number of challenging issues need to be considered before drawing causal conclusions about TCE exposure and cancer from these data.
Collapse
Affiliation(s)
- Cheryl Siegel Scott
- National Center for Environmental Assessment, Office of Research and Development, U.S. Environmental Protection Agency, Washington, DC, USA.
| | | |
Collapse
|
32
|
Mally A, Walker CL, Everitt JI, Dekant W, Vamvakas S. Analysis of renal cell transformation following exposure to trichloroethene in vivo and its metabolite S-(dichlorovinyl)-L-cysteine in vitro. Toxicology 2006; 224:108-18. [PMID: 16730402 DOI: 10.1016/j.tox.2006.04.036] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2006] [Revised: 04/19/2006] [Accepted: 04/19/2006] [Indexed: 11/27/2022]
Abstract
Trichloroethene (TCE) is classified as a potential human carcinogen although there is a significant debate regarding the mechanism of TCE induced renal tumor formation. This controversy stems in part from the extremely high doses of TCE required to induce renal tumors and the potential contribution of the associated nephrotoxicity to tumorigenesis. We have used Eker rats, which are uniquely susceptible to renal carcinogens, to determine if exposures to TCE in vivo or exposure to its metabolite S-(dichlorovinyl)-L-cysteine (DCVC) in vitro can transform kidney epithelial cells in the absence of cytotoxicity. Treatment with TCE (0, 100, 250, 500, 1000 mg/kg bw by gavage, 5 days a week) for 13 weeks resulted in a significant increase in cell proliferation in kidney tubule cells, but did not enhance formation of preneoplastic lesions or tumor incidence in Eker rat kidneys as compared to controls. In vitro, concentrations of DCVC, which reduced cell survival to 50%, were able to transform rat kidney epithelial cells. However, no carcinogen-specific mutations were identified in the VHL or Tsc-2 tumor suppressor genes in the transformants. Taken together, the inability of TCE to enhance formation of preneoplastic changes or neoplasia and the absence of carcinogen-specific alteration of genes accepted to be critical for renal tumor development suggest that TCE mediated carcinogenicity may occur secondary to continuous toxic injury and sustained regenerative cell proliferation.
Collapse
Affiliation(s)
- Angela Mally
- Department of Toxicology, University of Würzburg, Versbacher Str. 9, 97078 Würzburg, Germany.
| | | | | | | | | |
Collapse
|
33
|
Banks RE, Tirukonda P, Taylor C, Hornigold N, Astuti D, Cohen D, Maher ER, Stanley AJ, Harnden P, Joyce A, Knowles M, Selby PJ. Genetic and epigenetic analysis of von Hippel-Lindau (VHL) gene alterations and relationship with clinical variables in sporadic renal cancer. Cancer Res 2006; 66:2000-11. [PMID: 16488999 DOI: 10.1158/0008-5472.can-05-3074] [Citation(s) in RCA: 201] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Genetic and epigenetic changes in the von Hippel-Lindau (VHL) tumor suppressor gene are common in sporadic conventional renal cell carcinoma (cRCC). Further insight into the clinical significance of these changes may lead to increased biological understanding and identification of subgroups of patients differing prognostically or who may benefit from specific targeted treatments. We have comprehensively examined the VHL status in tissue samples from 115 patients undergoing nephrectomy, including 96 with sporadic cRCC. In patients with cRCC, loss of heterozygosity was found in 78.4%, mutation in 71%, and promoter methylation in 20.4% of samples. Multiplex ligation-dependent probe amplification identified intragenic copy number changes in several samples including two which were otherwise thought to be VHL-noninvolved. Overall, evidence of biallelic inactivation was found in 74.2% of patients with cRCC. Many of the mutations were novel and approximately two-thirds were potentially truncating. Examination of these and other published findings confirmed mutation hotspots affecting codons 117 and 164, and revealed a common region of mutation in codons 60 to 78. Gender-specific differences in methylation and mutation were seen, although not quite achieving statistical significance (P = 0.068 and 0.11), and a possible association between methylation and polymorphism was identified. No significant differences were seen between VHL subgroups with regard to clinicopathologic features including stage, grade, tumor size, cancer-free and overall survival, with the exception of a significant association between loss of heterozygosity and grade, although a possible trend for survival differences based on mutation location was apparent.
Collapse
Affiliation(s)
- Rosamonde E Banks
- Cancer Research UK Clinical Centre, St. James's University Hospital, Leeds, United Kingdom.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Abstract
Cysteine S-conjugate beta-lyases are pyridoxal 5'-phosphate-containing enzymes that catalyze beta-elimination reactions with cysteine S-conjugates that possess an electron-withdrawing group attached at the sulfur. The end products of the beta-lyase reaction are pyruvate, ammonium and a sulfur-containing fragment. If the sulfur-containing fragment is reactive, the parent cysteine S-conjugate may be toxic, particularly to kidney mitochondria. Halogenated alkenes are examples of electrophiles that are bioactivated (toxified) by conversion to cysteine S-conjugates. These conjugates are converted by cysteine S-conjugate beta-lyases to thioacylating fragments. Several cysteine S-conjugates found in allium foods (garlic and onion) are beta-lyase substrates. This finding may account in part for the chemopreventive activity of allium products. This review (1) identifies enzymes that catalyze cysteine S-conjugate beta-lyase reactions, (2) suggests that toxicant channeling may contribute to halogenated cysteine S-conjugate-induced toxicity to mitochondria, and (3) proposes mechanisms that may contribute to the antiproliferative effects of sulfur-containing fragments eliminated from allium-derived cysteine S-conjugates.
Collapse
Affiliation(s)
- A J L Cooper
- Department of Biochemistry, Weill Medical College, Cornell University, New York, New York, USA.
| | | |
Collapse
|
35
|
Lock EA, Reed CJ. Trichloroethylene: mechanisms of renal toxicity and renal cancer and relevance to risk assessment. Toxicol Sci 2006; 91:313-31. [PMID: 16421178 DOI: 10.1093/toxsci/kfj107] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
1,1,2-Trichloroethylene (TCE) is an important solvent that is widespread in the environment. We have reviewed carcinogenicity data from seven bioassays with regard to renal injury and renal tumors. We report a consistent but low incidence of renal tubule carcinoma in male rats. Epidemiology studies on workers exposed to TCE (and other chlorinated solvents) indicate a weak association between high-level exposure and renal cancer. There appears to be a threshold below which no renal injury or carcinogenicity is expected to arise. TCE is not acutely nephrotoxic to rats or mice, but subchronic exposure to rats produces a small increase in urinary markers of renal injury. Following chronic exposure, pathological changes (toxic nephrosis and a high incidence of cytomegaly and karyomegaly) were observed. The basis for the chronic renal injury probably involves bioactivation of TCE. Based on the classification by E. A. Lock and G. C. Hard (2004, Crit. Rev. Toxicol. 34, 211-299) of chemicals that induce renal tubule tumors, we found no clear evidence to place TCE in category 1 or 2 (chemicals that directly or indirectly interact with renal DNA), category 4 (direct cytotoxicity and sustained tubule cell regeneration), category 5 (indirect cytotoxicity and sustained tubule cell regeneration associated with alpha2u-globulin accumulation), or category 6 (exacerbation of spontaneous chronic progressive nephropathy). TCE is best placed in category 3, chemicals that undergo conjugation with GSH and subsequent enzymatic activation to a reactive species. The implication for human risk assessment is that TCE should not automatically be judged by linear default methods; benchmark methodology could be used.
Collapse
Affiliation(s)
- Edward A Lock
- School of Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool, L3 3AF United Kingdom.
| | | |
Collapse
|
36
|
van Houwelingen KP, van Dijk BAC, Hulsbergen-van de Kaa CA, Schouten LJ, Gorissen HJM, Schalken JA, van den Brandt PA, Oosterwijk E. Prevalence of von Hippel-Lindau gene mutations in sporadic renal cell carcinoma: results from The Netherlands cohort study. BMC Cancer 2005; 5:57. [PMID: 15932632 PMCID: PMC1177929 DOI: 10.1186/1471-2407-5-57] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2005] [Accepted: 06/02/2005] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Biallelic von Hippel-Lindau (VHL) gene defects, a rate-limiting event in the carcinogenesis, occur in approximately 75% of sporadic clear-cell Renal Cell Carcinoma (RCC). We studied the VHL mutation status in a large population-based case group. METHODS Cases were identified within the Netherlands cohort study on diet and cancer, which includes 120,852 men and women. After 11.3 years of follow-up, 337 incident cases with histologically confirmed epithelial cancers were identified. DNA was isolated from paraffin material collected from 51 pathology laboratories and revised by one pathologist, leaving material from 235 cases. VHL mutational status was assessed by SSCP followed by direct sequencing, after testing SSCP as a screening tool in a subsample. RESULTS The number of mutations was significantly higher for clear-cell RCC compared to other histological types. We observed 131 mutations in 114 out of 187 patients (61%) with clear-cell RCC. The majority of mutations were truncating mutations (47%). The mean tumor size was 72.7 mm for mutated tumors compared to 65.3 mm for wildtype tumors (p = 0.06). No statistically significant differences were observed for nuclear grade, TNM distribution or stage. In other histological types, we observed 8 mutations in 7 out of 48 patients (15%), 1 mutation in 1 of 6 oncocytoma, 3 mutations in 2 of 7 chromophobe RCC, 2 mutations in 2 of 30 papillary RCC, no mutations in 1 collecting duct carcinoma and 2 mutations in 2 of 4 unclassified RCC. CONCLUSION VHL mutations were detected in 61% of sporadic clear-cell RCC. VHL mutated and wildtype clear-cell RCC did not differ with respect to most parameters.
Collapse
Affiliation(s)
- Kjeld P van Houwelingen
- Department of Urology, University Medical Center Nijmegen, P.O. Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Boukje AC van Dijk
- Department of Epidemiology, NUTRIM, Maastricht University, P.O. Box 616, 6200 MD Maastricht, the Netherlands
| | | | - Leo J Schouten
- Department of Epidemiology, NUTRIM, Maastricht University, P.O. Box 616, 6200 MD Maastricht, the Netherlands
| | - Hanneke JM Gorissen
- Department of Urology, University Medical Center Nijmegen, P.O. Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Jack A Schalken
- Department of Urology, University Medical Center Nijmegen, P.O. Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Piet A van den Brandt
- Department of Epidemiology, NUTRIM, Maastricht University, P.O. Box 616, 6200 MD Maastricht, the Netherlands
| | - Egbert Oosterwijk
- Department of Urology, University Medical Center Nijmegen, P.O. Box 9101, 6500 HB Nijmegen, the Netherlands
| |
Collapse
|
37
|
Jaremko M, Justenhoven C, Abraham BK, Schroth W, Fritz P, Brod S, Vollmert C, Illig T, Brauch H. MALDI-TOF MS and TaqMan® assisted SNP genotyping of DNA isolated from formalin-fixed and paraffin-embedded tissues (FFPET). Hum Mutat 2005; 25:232-8. [PMID: 15706592 DOI: 10.1002/humu.20141] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Formalin-fixed paraffin-embedded tissues (FFPET) from archived clinical samples provide an invaluable source for large-scale molecular genetic studies. Pharmacogenetic investigations that require long-term clinical follow-up data of patients may particularly benefit from FFPET analysis. Matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and TaqMan-based (Thermus aquaticus polymerase) methodologies have become standard genotyping procedures. However, no data are available on the applicability of MALDI-TOF MS to the genotyping of low quality DNA, as it is usually obtained from FFPET, and data from TaqMan genotyping are limited. We isolated constitutional DNA from 274 FFPET samples (229 patients with breast cancer and 45 patients with benign breast diseases) and genotyped 15 polymorphic loci in 10 genes. Nine SNPs were genotyped by MALDI-TOF MS, and six were genotyped by the TaqMan methodology. We established rates for successful allele assignment for all FFPET, for FFPET prepared prior to 1990, and for FFPET prepared post-1990. Both methodologies showed high success rates ranging between 70.9 and 99.6% (mean: 91.8%) for MALDI-TOF MS and between 82.3 and 97.7% (mean: 91.0%) for TaqMan genotyping. No significant differences in genotyping performances for FFPET prepared prior to 1990 or post-1990 were observed. With the exception of one, all other genotype frequencies were in Hardy-Weinberg equilibrium. Furthermore, genotype frequencies matched those observed in a German breast cancer population and other Caucasian populations. Our study shows for the first time that MALDI-TOF MS and TaqMan genotyping procedures provide reliable data, and are therefore applicable in studies that require large scale FFPET genotyping.
Collapse
Affiliation(s)
- Malgorzata Jaremko
- Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Lewandowski TA, Rhomberg LR. A proposed methodology for selecting a trichloroethylene inhalation unit risk value for use in risk assessment. Regul Toxicol Pharmacol 2005; 41:39-54. [PMID: 15649826 DOI: 10.1016/j.yrtph.2004.09.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2004] [Revised: 09/28/2004] [Accepted: 09/28/2004] [Indexed: 11/22/2022]
Abstract
U.S. EPA's 2001 draft assessment of trichloroethylene (TCE) toxicity reviews the existing human and animal data on TCE carcinogenicity and proposes a 20-fold range of cancer potency values for use in risk assessment. Each value in the range is derived from a different source of data, either animal bioassays or epidemiology studies, and thus the range does not represent a distribution which can be characterized by statistical parameters such as a mean or 95% confidence interval. The U.S. EPA suggests users choose a single slope factor from among those it describes as appropriate for the population of interest and mode of exposure, but little guidance is given for making this choice. We propose an approach for determining the most scientifically defensible carcinogenic inhalation unit risk estimate from the range of slope factors developed by U.S. EPA, one that relies on accepted principles for evaluating scientific studies. Based on these considerations, we identify the most appropriate interim unit risk for low-level inhalation exposure as 9 x 10(-7) per microg/m(3). This approach may have fairly broad utility if U.S. EPA elects to use a similar approach in future assessments of other chemicals.
Collapse
Affiliation(s)
- T A Lewandowski
- Gradient Corporation, 600 Stewart Street, Suite 803, Seattle, WA 98101, USA.
| | | |
Collapse
|