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  1. Article: Molecular responses to xenoestrogens: mechanistic insights from toxicogenomics.

    Moggs, Jonathan G

    Toxicology

    2005  Volume 213, Issue 3, Page(s) 177–193

    Abstract: The xenoestrogen group of endocrine disruptors has the potential to cause reproductive and developmental effects through stimulation or disruption of sex steroid nuclear receptor signalling pathways. A more detailed understanding of the ways in which ... ...

    Abstract The xenoestrogen group of endocrine disruptors has the potential to cause reproductive and developmental effects through stimulation or disruption of sex steroid nuclear receptor signalling pathways. A more detailed understanding of the ways in which xenoestrogens interact with biological systems at the molecular level will provide a mechanistic basis for improved safety assessment. The recent sequencing of mammalian genomes has driven the development of toxicogenomic technologies, including microarray based gene expression profiling, which allow the expression levels of thousands of genes to be measured simultaneously. Since the cellular responses to xenoestrogens are predominantly mediated by estrogen receptors, which function as ligand-activated transcription factors to regulate gene expression, the application of toxicogenomics has great potential for providing insights into the molecular mechanisms of xenoestrogen action. A major challenge in applying toxicogenomics to the field of endocrine disruption is the need to define how xenoestrogen-induced changes in gene expression relate to conventional physiological and toxicological endpoints. Gene Ontology Mapping, Pathway Mapping and Phenotypic Anchoring of xenoestrogen-induced gene expression changes to cellular pathways and processes represent key steps in defining these relationships. Mechanistic insights into how xenoestrogens target specific genes and into the functional significance of xenoestrogen-induced alterations in gene expression can be further enhanced by combining transcript profiling with transgenic animal models or cell-based systems in which the estrogen receptor signalling pathways have been modified experimentally. This review illustrates how these toxicogenomic approaches are providing an unprecedented amount of mechanistic information on the molecular responses to xenoestrogens and how they are likely to impact on hazard and risk assessment.
    MeSH term(s) Animals ; Awards and Prizes ; Estrogens, Non-Steroidal/toxicity ; Humans ; Societies, Scientific ; Toxicogenetics ; United Kingdom ; Xenobiotics/toxicity
    Chemical Substances Estrogens, Non-Steroidal ; Xenobiotics
    Language English
    Publishing date 2005-10-01
    Publishing country Ireland
    Document type Lectures
    ZDB-ID 184557-3
    ISSN 1879-3185 ; 0300-483X
    ISSN (online) 1879-3185
    ISSN 0300-483X
    DOI 10.1016/j.tox.2005.05.020
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Derisking Drug-Induced Carcinogenicity for Novel Therapeutics.

    Moggs, Jonathan G / MacLachlan, Timothy / Martus, Hans-Joerg / Bentley, Philip

    Trends in cancer

    2016  Volume 2, Issue 8, Page(s) 398–408

    Abstract: Assessing the carcinogenic potential of innovative drugs spanning diverse therapeutic modalities and target biology represents a major challenge during drug development. Novel modalities, such as cell and gene therapies that involve intrinsic genetic ... ...

    Abstract Assessing the carcinogenic potential of innovative drugs spanning diverse therapeutic modalities and target biology represents a major challenge during drug development. Novel modalities, such as cell and gene therapies that involve intrinsic genetic modification of the host genome, require distinct approaches for identification of cancer hazard. We emphasize the need for customized weight-of-evidence cancer risk assessments based on mode of action that balance multiple options for preclinical identification of cancer hazard with appropriate labeling of clinical products and risk management plans. We review how advances in molecular carcinogenesis can enhance mechanistic interpretation and preclinical indicators of neoplasia, and recommend that drug targets be systematically assessed for potential association with tumorigenic phenotypes via genetic models and cancer genome resources.
    Language English
    Publishing date 2016-08
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 2852626-0
    ISSN 2405-8025 ; 2405-8033 ; 2405-8033
    ISSN (online) 2405-8025 ; 2405-8033
    ISSN 2405-8033
    DOI 10.1016/j.trecan.2016.07.003
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  3. Article ; Online: Defining baseline epigenetic landscapes in the rat liver.

    Thomson, John P / Ottaviano, Raffaele / Buesen, Roland / Moggs, Jonathan G / Schwarz, Michael / Meehan, Richard R

    Epigenomics

    2017  Volume 9, Issue 12, Page(s) 1503–1527

    Abstract: Aim: Characterization of the hepatic epigenome following exposure to chemicals and therapeutic drugs provides novel insights into toxicological and pharmacological mechanisms, however appreciation of genome-wide inter- and intra-strain baseline ... ...

    Abstract Aim: Characterization of the hepatic epigenome following exposure to chemicals and therapeutic drugs provides novel insights into toxicological and pharmacological mechanisms, however appreciation of genome-wide inter- and intra-strain baseline epigenetic variation, particularly in under-characterized species such as the rat is limited. Material & methods: To enhance the utility of epigenomic endpoints safety assessment, we map both DNA modifications (5-methyl-cytosine and 5-hydroxymethyl-cytosine) and enhancer related chromatin marks (H3K4me1 and H3K27ac) across multiple male and female rat livers for two important outbred laboratory rat strains (Sprague-Dawley and Wistar). Results & conclusion: Integration of DNA modification, enhancer chromatin marks and gene expression profiles reveals clear gender-specific chromatin states at genes which exhibit gender-specific transcription. Taken together this work provides a valuable baseline liver epigenome resource for rat strains that are commonly used in chemical and pharmaceutical safety assessment.
    MeSH term(s) Animals ; Chromatin/metabolism ; CpG Islands ; DNA Methylation ; Databases, Genetic ; Epigenesis, Genetic ; Female ; Genetic Variation ; Histone Code ; Liver/metabolism ; Male ; Rats ; Rats, Sprague-Dawley ; Rats, Wistar ; Sex Factors
    Chemical Substances Chromatin
    Language English
    Publishing date 2017-11-13
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2537199-X
    ISSN 1750-192X ; 1750-1911
    ISSN (online) 1750-192X
    ISSN 1750-1911
    DOI 10.2217/epi-2017-0029
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Derisking Drug-Induced Carcinogenicity for Novel Therapeutics

    Moggs, Jonathan G. / MacLachlan, Timothy / Martus, Hans-Joerg / Bentley, Philip

    Trends in Cancer. 2016,

    2016  

    Abstract: Assessing the carcinogenic potential of innovative drugs spanning diverse therapeutic modalities and target biology represents a major challenge during drug development. Novel modalities, such as cell and gene therapies that involve intrinsic genetic ... ...

    Abstract Assessing the carcinogenic potential of innovative drugs spanning diverse therapeutic modalities and target biology represents a major challenge during drug development. Novel modalities, such as cell and gene therapies that involve intrinsic genetic modification of the host genome, require distinct approaches for identification of cancer hazard. We emphasize the need for customized weight-of-evidence cancer risk assessments based on mode of action that balance multiple options for preclinical identification of cancer hazard with appropriate labeling of clinical products and risk management plans. We review how advances in molecular carcinogenesis can enhance mechanistic interpretation and preclinical indicators of neoplasia, and recommend that drug targets be systematically assessed for potential association with tumorigenic phenotypes via genetic models and cancer genome resources.
    Keywords cancer risk assessment ; carcinogenicity ; drug target
    Language English
    Publishing place Elsevier Inc.
    Document type Article ; Online
    Note Pre-press version
    ZDB-ID 2852626-0
    ISSN 2405-8033 ; 2405-8025 ; 2405-8033
    ISSN (online) 2405-8033 ; 2405-8025
    ISSN 2405-8033
    DOI 10.1016/j.trecan.2016.07.003
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  5. Article ; Online: Evaluation of 5-methylcytosine and 5-hydroxymethylcytosine as potential biomarkers for characterisation of chemical allergens.

    Chapman, Victoria L / Terranova, Rémi / Moggs, Jonathan G / Kimber, Ian / Dearman, Rebecca J

    Toxicology

    2016  Volume 340, Page(s) 17–26

    Abstract: Epigenetic regulation of gene expression plays a pivotal role in the orchestration of immune responses. Chemical allergens form two categories: skin sensitizing chemicals associated with allergic contact dermatitis, and chemicals that cause sensitization ...

    Abstract Epigenetic regulation of gene expression plays a pivotal role in the orchestration of immune responses. Chemical allergens form two categories: skin sensitizing chemicals associated with allergic contact dermatitis, and chemicals that cause sensitization of the respiratory tract and occupational asthma. In mice these are characterized by different T helper (Th) cell responses. Changes in DNA methylation in particular have been implicated in the in vivo responses to chemical allergy. As such it was hypothesised that differentially methylated regions (DMR) may provide candidates biomarkers of chemical allergy To examine this, mice were exposed to 2,4-dinitrochlorobenzene (DNCB; a contact allergen) or trimellitic anhydride (TMA; a respiratory allergen). DNA from draining lymph nodes was processed for methylated (5mC) and hydroxymethylated (5hmC) DNA immunoprecipitation (MeDIP/hMeDIP) then selected DMR analysed by qPCR. We describe a number of DMRs which, by combined analysis of 5mC and 5hmC, differentiate between responses induced by DNCB and those by TMA. Furthermore, these changes in methylation are specific to the draining lymph node. The Gmpr DMR is suggested as a possible biomarker for contact allergen-induced immune responses; it is characterised by divergent levels of 5mC and 5hmC DNCB-treated mice only. In contrast, the Nwc DMR was characterised by divergent 5mC and 5hmC specifically in response to TMA, highlighting its possible utility as a biomarker for responses induced by chemical respiratory allergens. These data not only represent novel analysis of 5hmC in response to chemical allergy in vivo, but with further investigation, may also provide a possible basis for differentiation between classes of chemical allergens.
    MeSH term(s) 5-Methylcytosine/metabolism ; Allergens/toxicity ; Animals ; Cytosine/analogs & derivatives ; Cytosine/metabolism ; DNA Fragmentation ; DNA Methylation/drug effects ; Dinitrochlorobenzene/toxicity ; Epigenesis, Genetic/drug effects ; Female ; Immunoprecipitation ; Local Lymph Node Assay ; Lymph Nodes/drug effects ; Lymph Nodes/immunology ; Lymph Nodes/metabolism ; Lymph Nodes/pathology ; Mice, Inbred BALB C ; Phthalic Anhydrides/toxicity ; Polymerase Chain Reaction ; Promoter Regions, Genetic/drug effects
    Chemical Substances Allergens ; Phthalic Anhydrides ; 5-hydroxymethylcytosine (1123-95-1) ; 5-Methylcytosine (6R795CQT4H) ; trimellitic anhydride (80T61EUU7H) ; Cytosine (8J337D1HZY) ; Dinitrochlorobenzene (GE3IBT7BMN)
    Language English
    Publishing date 2016-01-18
    Publishing country Ireland
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 184557-3
    ISSN 1879-3185 ; 0300-483X
    ISSN (online) 1879-3185
    ISSN 0300-483X
    DOI 10.1016/j.tox.2015.12.003
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: A Synopsis of the "Influence of Epigenetics, Genetics, and Immunology" Session Part A at the 35th Annual Society of Toxicologic Pathology Symposium.

    Harrill, Alison H / Moggs, Jonathan G / Adkins, Karissa K / Augustin, Hellmut G / Johnson, Robert C / Leach, Michael W

    Toxicologic pathology

    2017  Volume 45, Issue 1, Page(s) 114–118

    Abstract: The overarching theme of the 2016 Society of Toxicology Pathology's Annual Symposium was "The Basis and Relevance of Variation in Toxicologic Responses." Session 4 focused on genetic variation as a potential source for variability in toxicologic ... ...

    Abstract The overarching theme of the 2016 Society of Toxicology Pathology's Annual Symposium was "The Basis and Relevance of Variation in Toxicologic Responses." Session 4 focused on genetic variation as a potential source for variability in toxicologic responses within nonclinical toxicity studies and further explored how knowledge of genetic traits might enable targeted prospective and retrospective studies in drug development and human health risk assessment. In this session, the influence of both genetic sequence variation and epigenetic modifications on toxicologic responses and their implications for understanding risk were explored. In this overview, the presentations in this session will be summarized, with a goal of exploring the ramifications of genetic and epigenetic variability within and across species for toxicity studies and disseminating information regarding novel tools to harness this variability to advance understanding of toxicologic responses across populations.
    Language English
    Publishing date 2017-01
    Publishing country United States
    Document type Journal Article
    ZDB-ID 841009-4
    ISSN 1533-1601 ; 0192-6233
    ISSN (online) 1533-1601
    ISSN 0192-6233
    DOI 10.1177/0192623316670781
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  7. Article ; Online: Epigenetic profiles as defined signatures of xenobiotic exposure.

    Thomson, John P / Moggs, Jonathan G / Wolf, C Roland / Meehan, Richard R

    Mutation research. Genetic toxicology and environmental mutagenesis

    2013  Volume 764-765, Page(s) 3–9

    Abstract: With the advent of high resolution sequencing technologies there has been increasing interest in the study of genome-wide epigenetic modification patterns that govern the underlying gene expression events of a particular cell or tissue type. There is now ...

    Abstract With the advent of high resolution sequencing technologies there has been increasing interest in the study of genome-wide epigenetic modification patterns that govern the underlying gene expression events of a particular cell or tissue type. There is now mounting evidence that perturbations to the epigenetic landscape occur during a host of cellular processes including normal proliferation/differentiation and aberrant outcomes such as carcinogenesis. Furthermore, epigenetic perturbations have been associated with exposure to a range of drugs and toxicants, including non-genotoxic carcinogens (NGCs). Although a variety of epigenetic modifications induced by NGCs have been studied previously, recent genome-wide integrated epigenomic and transcriptomic studies reveal for the first time the extent and dynamic nature of the epigenetic perturbations resulting from xenobiotic exposure. The interrogation and integration of one such epigenetic mark, the newly discovered 5-hydroxymethylcytosine (5hmC) modification, reveals that drug treatment associated perturbations of the epigenome can result in unique epigenetic signatures. This review focuses on how recent advances in the field of epigenetics can enhance our mechanistic understanding of xenobiotic exposure and provide novel safety biomarkers.
    MeSH term(s) 5-Methylcytosine/analogs & derivatives ; Animals ; Carcinogens/toxicity ; Chemical Safety ; Chromatin/metabolism ; Cytosine/analogs & derivatives ; Cytosine/metabolism ; DNA Methylation ; Disease Progression ; Epigenesis, Genetic ; Epigenomics ; Genetic Markers ; Genome ; Humans ; Transcriptome ; Xenobiotics/toxicity
    Chemical Substances Carcinogens ; Chromatin ; Genetic Markers ; Xenobiotics ; 5-hydroxymethylcytosine (1123-95-1) ; 5-Methylcytosine (6R795CQT4H) ; Cytosine (8J337D1HZY)
    Language English
    Publishing date 2013-08-31
    Publishing country Netherlands
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ISSN 1879-3592
    ISSN (online) 1879-3592
    DOI 10.1016/j.mrgentox.2013.08.007
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: The role of chromatin in molecular mechanisms of toxicity.

    Moggs, Jonathan G / Orphanides, George

    Toxicological sciences : an official journal of the Society of Toxicology

    2004  Volume 80, Issue 2, Page(s) 218–224

    Abstract: Eukaryotic cells store their genetic information in the form of a highly organized nucleoprotein complex termed chromatin. The high degree of compaction of DNA within chromatin places severe constraints on proteins that require access to the DNA template ...

    Abstract Eukaryotic cells store their genetic information in the form of a highly organized nucleoprotein complex termed chromatin. The high degree of compaction of DNA within chromatin places severe constraints on proteins that require access to the DNA template to facilitate gene transcription, DNA replication, and DNA repair. As a consequence, eukaryotic cells have developed sophisticated mechanisms to allow chromatin to be rapidly decompacted locally for access by DNA-binding proteins. Once thought to play only a structural role, it now appears that chromatin plays a key regulatory role by marshalling access to the DNA template. We have reviewed the role played by chromatin in the cellular response to physiological and toxicological stimuli and described how changes in chromatin structure may in the future be used as markers of toxicity. We also review the evidence that chromatin itself is the direct target of certain toxicants and that toxicant-induced perturbations in chromatin structure may precipitate adverse effects.
    MeSH term(s) Animals ; Chromatin/drug effects ; Chromatin/genetics ; DNA/chemistry ; DNA/metabolism ; Environmental Pollutants/toxicity ; Gene Expression/drug effects ; Histones/chemistry ; Histones/metabolism ; Humans ; Mutagens/toxicity ; Stress, Physiological/genetics ; Toxicology ; Xenobiotics/toxicity
    Chemical Substances Chromatin ; Environmental Pollutants ; Histones ; Mutagens ; Xenobiotics ; DNA (9007-49-2)
    Language English
    Publishing date 2004-08
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 1420885-4
    ISSN 1096-0929 ; 1096-6080
    ISSN (online) 1096-0929
    ISSN 1096-6080
    DOI 10.1093/toxsci/kfh164
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  9. Article: Genomic analysis of stress response genes.

    Moggs, Jonathan G / Orphanides, George

    Toxicology letters

    2003  Volume 140-141, Page(s) 149–153

    Abstract: ... in which signalling components are disrupted (e.g. small molecule protein kinase inhibitors) to reveal ...

    Abstract Mammalian cells respond to a wide range of external stimuli including growth factors, peptide hormones, cytokines, osmotic stress, heat shock, pharmacological agents and toxicants via multiple signalling pathways. Genome-wide transcript profiling simultaneously monitors the gene expression programs downstream of all signal transduction pathways and can identify novel molecular targets for stress-inducing signals. Our laboratory has combined transcript profiling of cytotoxic compounds with experimental systems in which signalling components are disrupted (e.g. small molecule protein kinase inhibitors) to reveal the contribution of specific signalling pathways to the transcriptional response to toxicant-induced stress. A complementary approach for elucidating the molecular mechanisms that regulate transcriptional responses to toxicants involves DNA sequence analysis of gene regulatory regions obtained via data mining of recently completed mammalian genome sequences. Together, these approaches reveal the molecular mechanisms used to finely tune alterations in gene expression, enabling cells to react in an appropriate manner to external stress-inducing stimuli.
    MeSH term(s) Gene Expression Regulation, Enzymologic/genetics ; Genome, Human ; Humans ; Oligonucleotide Array Sequence Analysis/methods ; Signal Transduction/genetics
    Language English
    Publishing date 2003-04-11
    Publishing country Netherlands
    Document type Journal Article ; Review
    ZDB-ID 433788-8
    ISSN 1879-3169 ; 0378-4274
    ISSN (online) 1879-3169
    ISSN 0378-4274
    DOI 10.1016/s0378-4274(02)00501-5
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  10. Article: Evaluation of 5-methylcytosine and 5-hydroxymethylcytosine as potential biomarkers for characterisation of chemical allergens

    Chapman, Victoria L / Ian Kimber / Jonathan G. Moggs / Rebecca J. Dearman / Rémi Terranova

    Toxicology. 2016 Jan. 18, v. 340

    2016  

    Abstract: Epigenetic regulation of gene expression plays a pivotal role in the orchestration of immune responses. Chemical allergens form two categories: skin sensitizing chemicals associated with allergic contact dermatitis, and chemicals that cause sensitization ...

    Abstract Epigenetic regulation of gene expression plays a pivotal role in the orchestration of immune responses. Chemical allergens form two categories: skin sensitizing chemicals associated with allergic contact dermatitis, and chemicals that cause sensitization of the respiratory tract and occupational asthma. In mice these are characterized by different T helper (Th) cell responses. Changes in DNA methylation in particular have been implicated in the in vivo responses to chemical allergy. As such it was hypothesised that differentially methylated regions (DMR) may provide candidates biomarkers of chemical allergy To examine this, mice were exposed to 2,4-dinitrochlorobenzene (DNCB; a contact allergen) or trimellitic anhydride (TMA; a respiratory allergen). DNA from draining lymph nodes was processed for methylated (5mC) and hydroxymethylated (5hmC) DNA immunoprecipitation (MeDIP/hMeDIP) then selected DMR analysed by qPCR. We describe a number of DMRs which, by combined analysis of 5mC and 5hmC, differentiate between responses induced by DNCB and those by TMA. Furthermore, these changes in methylation are specific to the draining lymph node. The Gmpr DMR is suggested as a possible biomarker for contact allergen-induced immune responses; it is characterised by divergent levels of 5mC and 5hmC DNCB-treated mice only. In contrast, the Nwc DMR was characterised by divergent 5mC and 5hmC specifically in response to TMA, highlighting its possible utility as a biomarker for responses induced by chemical respiratory allergens. These data not only represent novel analysis of 5hmC in response to chemical allergy in vivo, but with further investigation, may also provide a possible basis for differentiation between classes of chemical allergens.
    Keywords allergens ; anhydrides ; asthma ; biomarkers ; CD4-positive T-lymphocytes ; contact dermatitis ; DNA ; DNA methylation ; epigenetics ; gene expression regulation ; hypersensitivity ; immune response ; lymph nodes ; mice ; precipitin tests ; quantitative polymerase chain reaction ; respiratory system
    Language English
    Dates of publication 2016-0118
    Size p. 17-26.
    Publishing place Elsevier Ireland Ltd
    Document type Article
    ZDB-ID 184557-3
    ISSN 1879-3185 ; 0300-483X
    ISSN (online) 1879-3185
    ISSN 0300-483X
    DOI 10.1016/j.tox.2015.12.003
    Database NAL-Catalogue (AGRICOLA)

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