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Doktorova TY, Azzi P, Hofer J, Messner CJ, Gaiser C, Werner S, Singh P, Hardy B, Suter-Dick L, Chesne C. How to Foster 'New Approach Methodology' Toxicologists. Altern Lab Anim 2022; 50:71-75. [PMID: 35179997 DOI: 10.1177/02611929221078945] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The need to reduce, refine and replace animal experimentation has led to a boom in the establishment of new approach methodologies (NAMs). This promising trend brings the hope that the replacement of animals by using NAMs will become increasingly accepted by regulators, included in legislation, and consequently more-often implemented by industry. The majority of NAMs, however, are still not very well understood, either due to the complexity of the applied approach or the data analysis workflow. A potential solution to this problem is the provision of better educational resources to scientists new to the area - showcasing the added value of NAMs and outlining various ways of overcoming issues associated with knowledge gaps. In this paper, the educational exchange between four institutions - namely, two universities and two SMEs - via a series of video training sessions, is described. The goal of this exchange was to showcase an exemplary event to help introduce scientists to non-animal approaches, and to actively support the development of resources enabling the use of alternatives to laboratory animals.
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Affiliation(s)
| | - Pamela Azzi
- Lebanese University, Faculty of Sciences, Hadath, Lebanon.,Biopredic International, Saint-Grégoire, France
| | - Joelle Hofer
- School of Life Sciences, University of Applied Sciences and Arts Northwestern Switzerland, Muttenz, Switzerland
| | - Catherine J Messner
- School of Life Sciences, University of Applied Sciences and Arts Northwestern Switzerland, Muttenz, Switzerland.,Swiss Centre for Applied Human Toxicology (SCAHT), Basel, Switzerland
| | - Carine Gaiser
- School of Life Sciences, University of Applied Sciences and Arts Northwestern Switzerland, Muttenz, Switzerland
| | - Sophie Werner
- School of Life Sciences, University of Applied Sciences and Arts Northwestern Switzerland, Muttenz, Switzerland
| | | | | | - Laura Suter-Dick
- School of Life Sciences, University of Applied Sciences and Arts Northwestern Switzerland, Muttenz, Switzerland.,Swiss Centre for Applied Human Toxicology (SCAHT), Basel, Switzerland
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Doktorova TY, Oki NO, Mohorič T, Exner TE, Hardy B. A semi-automated workflow for adverse outcome pathway hypothesis generation: The use case of non-genotoxic induced hepatocellular carcinoma. Regul Toxicol Pharmacol 2020; 114:104652. [PMID: 32251711 DOI: 10.1016/j.yrtph.2020.104652] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 01/10/2020] [Accepted: 03/29/2020] [Indexed: 02/07/2023]
Abstract
The utility of the Adverse Outcome Pathway (AOP) concept has been largely recognized by scientists, however, the AOP generation is still mainly done manually by screening through evidence and extracting probable associations. To accelerate this process and increase the reliability, we have developed an semi-automated workflow for AOP hypothesis generation. In brief, association mining methods were applied to high-throughput screening, gene expression, in vivo and disease data present in ToxCast and Comparative Toxicogenomics Database. This was supplemented by pathway mapping using Reactome to fill in gaps and identify events occurring at the cellular/tissue levels. Furthermore, in vivo data from TG-Gates was integrated to finally derive a gene, pathway, biochemical, histopathological and disease network from which specific disease sub-networks can be queried. To test the workflow, non-genotoxic-induced hepatocellular carcinoma (HCC) was selected as a case study. The implementation resulted in the identification of several non-genotoxic-specific HCC-connected genes belonging to cell proliferation, endoplasmic reticulum stress and early apoptosis. Biochemical findings revealed non-genotoxic-specific alkaline phosphatase increase. The explored non-genotoxic-specific histopathology was associated with early stages of hepatic steatosis, transforming into cirrhosis. This work illustrates the utility of computationally predicted constructs in supporting development by using pre-existing knowledge in a fast and unbiased manner.
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Affiliation(s)
- Tatyana Y Doktorova
- Edelweiss Connect GmbH, Hochbergerstrasse 60C, Technology Park Basel, Basel, Switzerland.
| | - Noffisat O Oki
- American Association for the Advancement of Science, Science & Technology Policy Fellow, USA; National Institutes of Health, Rockville, MD, USA
| | - Tomaž Mohorič
- Edelweiss Connect GmbH, Hochbergerstrasse 60C, Technology Park Basel, Basel, Switzerland
| | - Thomas E Exner
- Edelweiss Connect GmbH, Hochbergerstrasse 60C, Technology Park Basel, Basel, Switzerland
| | - Barry Hardy
- Edelweiss Connect GmbH, Hochbergerstrasse 60C, Technology Park Basel, Basel, Switzerland
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3
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Oki NO, Farcal L, Abdelaziz A, Florean O, Doktorova TY, Exner T, Kohonen P, Grafström R, Hardy B. Integrated analysis of in vitro data and the adverse outcome pathway framework for prioritization and regulatory applications: An exploratory case study using publicly available data on piperonyl butoxide and liver models. Toxicol In Vitro 2019; 54:23-32. [DOI: 10.1016/j.tiv.2018.09.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 08/31/2018] [Accepted: 09/03/2018] [Indexed: 01/30/2023]
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Ates G, Mertens B, Heymans A, Verschaeve L, Milushev D, Vanparys P, Roosens NHC, De Keersmaecker SCJ, Rogiers V, Doktorova TY. A novel genotoxin-specific qPCR array based on the metabolically competent human HepaRG™ cell line as a rapid and reliable tool for improved in vitro hazard assessment. Arch Toxicol 2018; 92:1593-1608. [DOI: 10.1007/s00204-018-2172-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 01/31/2018] [Indexed: 02/01/2023]
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Ates G, Raitano G, Heymans A, Van Bossuyt M, Vanparys P, Mertens B, Chesne C, Roncaglioni A, Milushev D, Benfenati E, Rogiers V, Doktorova TY. In silico tools and transcriptomics analyses in the mutagenicity assessment of cosmetic ingredients: a proof-of-principle on how to add weight to the evidence. Mutagenesis 2016; 31:453-61. [PMID: 26980085 DOI: 10.1093/mutage/gew008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Prior to the downstream development of chemical substances, including pharmaceuticals and cosmetics, their influence on the genetic apparatus has to be tested. Several in vitro and in vivo assays have been developed to test for genotoxicity. In a first tier, a battery of two to three in vitro tests is recommended to cover mutagenicity, clastogenicity and aneugenicity as main endpoints. This regulatory in vitro test battery is known to have a high sensitivity, which is at the expense of the specificity. The high number of false positive in vitro results leads to excessive in vivo follow-up studies. In the case of cosmetics it may even induce the ban of the particular compound since in Europe the use of experimental animals is no longer allowed for cosmetics. In this article, an alternative approach to derisk a misleading positive Ames test is explored. Hereto we first tested the performance of five existing computational tools to predict the potential mutagenicity of a data set of 132 cosmetic compounds with a known genotoxicity profile. Furthermore, we present, as a proof-of-principle, a strategy in which a combination of computational tools and mechanistic information derived from in vitro transcriptomics analyses is used to derisk a misleading positive Ames test result. Our data shows that this strategy may represent a valuable tool in a weight-of-evidence approach to further evaluate a positive outcome in an Ames test.
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Affiliation(s)
| | - Giuseppa Raitano
- IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Via La Masa 19, 20156 Milan, Italy
| | | | - Melissa Van Bossuyt
- Unit of Toxicology, Scientific Institute of Public Health (WIV-ISP), Juliette Wytsmanstraat 14, B-1050, Brussels, Belgium
| | | | - Birgit Mertens
- Unit of Toxicology, Scientific Institute of Public Health (WIV-ISP), Juliette Wytsmanstraat 14, B-1050, Brussels, Belgium
| | - Christophe Chesne
- Biopredic International, Parc d'activité de la Bretèche Bâtiment A4, 35760 Saint Grégoire, France and
| | - Alessandra Roncaglioni
- IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Via La Masa 19, 20156 Milan, Italy
| | | | - Emilio Benfenati
- IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Via La Masa 19, 20156 Milan, Italy
| | | | - Tatyana Y Doktorova
- Unit of Toxicology, Scientific Institute of Public Health (WIV-ISP), Juliette Wytsmanstraat 14, B-1050, Brussels, Belgium
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Herwig R, Gmuender H, Corvi R, Bloch KM, Brandenburg A, Castell J, Ceelen L, Chesne C, Doktorova TY, Jennen D, Jennings P, Limonciel A, Lock EA, McMorrow T, Phrakonkham P, Radford R, Slattery C, Stierum R, Vilardell M, Wittenberger T, Yildirimman R, Ryan M, Rogiers V, Kleinjans J. Inter-laboratory study of human in vitro toxicogenomics-based tests as alternative methods for evaluating chemical carcinogenicity: a bioinformatics perspective. Arch Toxicol 2015; 90:2215-2229. [PMID: 26525393 DOI: 10.1007/s00204-015-1617-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 10/19/2015] [Indexed: 01/29/2023]
Abstract
The assessment of the carcinogenic potential of chemicals with alternative, human-based in vitro systems has become a major goal of toxicogenomics. The central read-out of these assays is the transcriptome, and while many studies exist that explored the gene expression responses of such systems, reports on robustness and reproducibility, when testing them independently in different laboratories, are still uncommon. Furthermore, there is limited knowledge about variability induced by the data analysis protocols. We have conducted an inter-laboratory study for testing chemical carcinogenicity evaluating two human in vitro assays: hepatoma-derived cells and hTERT-immortalized renal proximal tubule epithelial cells, representing liver and kidney as major target organs. Cellular systems were initially challenged with thirty compounds, genome-wide gene expression was measured with microarrays, and hazard classifiers were built from this training set. Subsequently, each system was independently established in three different laboratories, and gene expression measurements were conducted using anonymized compounds. Data analysis was performed independently by two separate groups applying different protocols for the assessment of inter-laboratory reproducibility and for the prediction of carcinogenic hazard. As a result, both workflows came to very similar conclusions with respect to (1) identification of experimental outliers, (2) overall assessment of robustness and inter-laboratory reproducibility and (3) re-classification of the unknown compounds to the respective toxicity classes. In summary, the developed bioinformatics workflows deliver accurate measures for inter-laboratory comparison studies, and the study can be used as guidance for validation of future carcinogenicity assays in order to implement testing of human in vitro alternatives to animal testing.
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Affiliation(s)
- R Herwig
- Department Computational Molecular Biology, Max-Planck-Institute for Molecular Genetics, Ihnestr. 73, 14195, Berlin, Germany.
| | - H Gmuender
- Genedata AG, Margarethenstrasse 38, 4053, Basel, Switzerland
| | - R Corvi
- European Union Reference Laboratory for Alternatives to Animal Testing (EURL ECVAM), Institute for Health and Consumer Protection (IHCP), European Commission Joint Research Centre, TP 126, Via E. Fermi 2749, 21027, Ispra, Italy
| | - K M Bloch
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool, L3 3AF, UK
| | - A Brandenburg
- Genedata AG, Margarethenstrasse 38, 4053, Basel, Switzerland
| | - J Castell
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Valencia, Av. Blasco Ibanez 15, 46010, Valencia, Spain
| | - L Ceelen
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium
| | - C Chesne
- Biopredic International, Parc d'affaires de la Bretèche, Bldg. A4, 35760, St Gregoire, France
| | - T Y Doktorova
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium
| | - D Jennen
- Department of Toxicogenomics, Maastricht University, Maastricht, The Netherlands
| | - P Jennings
- Division of Physiology, Department of Physiology and Medical Physics, Medical University of Innsbruck, Innsbruck, Austria
| | - A Limonciel
- Division of Physiology, Department of Physiology and Medical Physics, Medical University of Innsbruck, Innsbruck, Austria
| | - E A Lock
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool, L3 3AF, UK
| | - T McMorrow
- Conway Institute, School of Biomolecular and Biomedical Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - P Phrakonkham
- European Union Reference Laboratory for Alternatives to Animal Testing (EURL ECVAM), Institute for Health and Consumer Protection (IHCP), European Commission Joint Research Centre, TP 126, Via E. Fermi 2749, 21027, Ispra, Italy
| | - R Radford
- Conway Institute, School of Biomolecular and Biomedical Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - C Slattery
- Conway Institute, School of Biomolecular and Biomedical Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - R Stierum
- Department of Risk Analysis for Products in Development, Netherlands Organisation for Applied Scientific Research (TNO), Utrechtseweg 48, 3704 HE, Zeist, The Netherlands
| | - M Vilardell
- Department Computational Molecular Biology, Max-Planck-Institute for Molecular Genetics, Ihnestr. 73, 14195, Berlin, Germany
| | - T Wittenberger
- Genedata AG, Margarethenstrasse 38, 4053, Basel, Switzerland
| | - R Yildirimman
- Department Computational Molecular Biology, Max-Planck-Institute for Molecular Genetics, Ihnestr. 73, 14195, Berlin, Germany
| | - M Ryan
- Conway Institute, School of Biomolecular and Biomedical Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - V Rogiers
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium
| | - J Kleinjans
- Department of Toxicogenomics, Maastricht University, Maastricht, The Netherlands
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Rodrigues RM, De Kock J, Doktorova TY, Rogiers V, Vanhaecke T. Measurement of Cytochrome P450 Enzyme Induction and Inhibition in Human Hepatoma Cells. Methods Mol Biol 2015; 1250:279-285. [PMID: 26272150 DOI: 10.1007/978-1-4939-2074-7_20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Cytochrome P450 enzymes are a diverse group of catalytic enzymes in the liver that are mainly responsible for the biotransformation of organic substances. Cytochrome P450 activity as well as both its induction and inhibition are key factors in drug biotransformation and can be involved in deactivation, activation, detoxification and toxification processes. Thus, the modulation of cytochrome P450 activity is an important parameter when evaluating the potential toxicity of chemical compounds using an in vitro system. The cytochrome P450 3A subfamily proteins are among the most important drug-metabolizing enzymes in human liver and are responsible for about half of all cytochrome P450-dependent drug oxidations. In vitro, these enzymes are active not only in primary human hepatocyte cultures, but also in differentiated human hepatoma HepaRG cells. The present protocol describes the culture of cryopreserved differentiated HepaRG cells and the evaluation of its cytochrome P450 activity upon exposure to a chemical compound using a commercially available luminogenic cytochrome P450 assay. This in vitro model can be used to monitor the induction and inhibition of cytochrome P450 3A following exposure to a particular test compound.
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Affiliation(s)
- Robim M Rodrigues
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium,
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Ates G, Doktorova TY, Pauwels M, Rogiers V. Retrospective analysis of the mutagenicity/genotoxicity data of the cosmetic ingredients present on the Annexes of the Cosmetic EU legislation (2000–12). Mutagenesis 2014; 29:115-21. [DOI: 10.1093/mutage/get068] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Doktorova TY, Yildirimman R, Vinken M, Vilardell M, Vanhaecke T, Gmuender H, Bort R, Brolen G, Holmgren G, Li R, Chesne C, van Delft J, Kleinjans J, Castell J, Bjorquist P, Herwig R, Rogiers V. Transcriptomic responses generated by hepatocarcinogens in a battery of liver-based in vitro models. Carcinogenesis 2013; 34:1393-402. [PMID: 23393228 DOI: 10.1093/carcin/bgt054] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
As the conventional approach to assess the potential of a chemical to cause cancer in humans still includes the 2-year rodent carcinogenicity bioassay, development of alternative methodologies is needed. In the present study, the transcriptomics responses following exposure to genotoxic (GTX) and non-genotoxic (NGTX) hepatocarcinogens and non-carcinogens (NC) in five liver-based in vitro models, namely conventional and epigenetically stabilized cultures of primary rat hepatocytes, the human hepatoma-derived cell lines HepaRG and HepG2 and human embryonic stem cell-derived hepatocyte-like cells, are examined. For full characterization of the systems, several bioinformatics approaches are employed including gene-based, ConsensusPathDB-based and classification analysis. They provide convincingly similar outcomes, namely that upon exposure to carcinogens, the HepaRG generates a gene classifier (a gene classifier is defined as a selected set of characteristic gene signatures capable of distinguishing GTX, NGTX carcinogens and NC) able to discriminate the GTX carcinogens from the NGTX carcinogens and NC. The other in vitro models also yield cancer-relevant characteristic gene groups for the GTX exposure, but some genes are also deregulated by the NGTX carcinogens and NC. Irrespective of the tested in vitro model, the most uniformly expressed pathways following GTX exposure are the p53 and those that are subsequently induced. The NGTX carcinogens triggered no characteristic cancer-relevant gene profiles in all liver-based in vitro systems. In conclusion, liver-based in vitro models coupled with transcriptomics techniques, especially in the case when the HepaRG cell line is used, represent valuable tools for obtaining insight into the mechanism of action and identification of GTX carcinogens.
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Affiliation(s)
- Tatyana Y Doktorova
- Department of Toxicology, Center for Pharmaceutical Research, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium
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Doktorova TY, Ellinger-Ziegelbauer H, Vinken M, Vanhaecke T, van Delft J, Kleinjans J, Ahr HJ, Rogiers V. Comparison of genotoxicant-modified transcriptomic responses in conventional and epigenetically stabilized primary rat hepatocytes with in vivo rat liver data. Arch Toxicol 2012; 86:1703-15. [PMID: 23052194 DOI: 10.1007/s00204-012-0946-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2011] [Accepted: 11/29/2011] [Indexed: 12/29/2022]
Abstract
The concept of mechanistic toxicogenomics implies that compound-induced changes in gene expression profiles provide valuable information about their mode of action. A growing number of research groups have presented evidence that whole-genome gene expression profiling techniques might be used as tools for in vivo and in vitro generation of gene signatures and elucidation of molecular mechanisms after exposure to toxic compounds. An important issue to be investigated is the in vivo relevance of in vitro-obtained data. In the current study, we compare the gene expression profiles generated in vitro, after exposing conventional and epigenetically stabilized primary rat hepatocytes to well-known genotoxic hepatocarcinogens (aflatoxin B1, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone and 2-nitrofluorene) with those derived in vivo after oral exposure of rats to these compounds. Similar statistical tools were applied on both sets of data. The major molecular pathways affected in the in vivo setting were DNA damage, detoxification and cell survival response, as previously described. In the conventional hepatocyte cultures, two of the three genotoxicants showed quite similar responses as in vivo with respect to these pathways. The third compound (2-nitrofluorene) revealed in vitro response which was not observed in vivo. In the epigenetically stabilized hepatocytes, in contrast to what was expected, the responses were less relevant for the in vivo situation. This study highlights the importance of in vitro/in vivo comparison of data that are generated using in vitro models and shows that conventional primary rat hepatocyte cultures represent an appropriate in vitro model to retrieve mechanistic information on the exposure to genotoxicants.
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Affiliation(s)
- Tatyana Y Doktorova
- Department of Toxicology, Center for Pharmaceutical Research (CePhar), Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, Brussels, Belgium.
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Doktorova TY, Ellinger-Ziegelbauer H, Vinken M, Vanhaecke T, van Delft J, Kleinjans J, Ahr HJ, Rogiers V. Comparison of hepatocarcinogen-induced gene expression profiles in conventional primary rat hepatocytes with in vivo rat liver. Arch Toxicol 2012; 86:1399-411. [PMID: 22484513 DOI: 10.1007/s00204-012-0847-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Accepted: 03/22/2012] [Indexed: 01/07/2023]
Abstract
At present, substantial efforts are focused on the development of in vitro assays coupled with "omics" technologies for the identification of carcinogenic substances as an alternative to the classical 2-year rodent carcinogenicity bioassay. A prerequisite for the eventual regulatory acceptance of such assays, however, is the in vivo relevance of the observed in vitro findings. In the current study, hepatocarcinogen-induced gene expression profiles generated after the exposure of conventional cultures of primary rat hepatocytes to three non-genotoxic carcinogens (methapyrilene hydrochloride, piperonyl butoxide, and Wy-14643), three genotoxic carcinogens (aflatoxin B1, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, and 2-nitrofluorene), and two non-carcinogens (nifedipine and clonidine) are compared with previously obtained in vivo data after oral administration for up to 14 days of the same hepatocarcinogens to rats. In addition to the comparison of deregulated genes and functions per compound between in vivo and in vitro models, the major discriminating cellular pathways found in vivo in livers of exposed rats were examined for deregulation in vitro. Further, in vivo-derived gene signatures for the identification of genotoxic versus non-genotoxic carcinogens are used to classify in vitro-tested hepatocarcinogens and non-carcinogens. In the primary hepatocyte cultures, two out of the three tested genotoxic carcinogens mimicked the in vivo-relevant DNA damage response and were correctly assessed. Exposure to the non-genotoxic hepatocarcinogens, however, triggered a relatively weak response in the in vitro system, with no clear similarities to in vivo. This study contributes to the further optimization of toxicogenomics predictive tools when applied in in vitro settings.
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Affiliation(s)
- Tatyana Y Doktorova
- Department of Toxicology, Center for Pharmaceutical Research, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium.
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Doktorova TY, Pauwels M, Vinken M, Vanhaecke T, Rogiers V. Opportunities for an alternative integrating testing strategy for carcinogen hazard assessment? Crit Rev Toxicol 2011; 42:91-106. [DOI: 10.3109/10408444.2011.623151] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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