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1.
Nature ; 541(7637): 359-364, 2017 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-28068672

RESUMO

Prostate tumours are highly variable in their response to therapies, but clinically available prognostic factors can explain only a fraction of this heterogeneity. Here we analysed 200 whole-genome sequences and 277 additional whole-exome sequences from localized, non-indolent prostate tumours with similar clinical risk profiles, and carried out RNA and methylation analyses in a subset. These tumours had a paucity of clinically actionable single nucleotide variants, unlike those seen in metastatic disease. Rather, a significant proportion of tumours harboured recurrent non-coding aberrations, large-scale genomic rearrangements, and alterations in which an inversion repressed transcription within its boundaries. Local hypermutation events were frequent, and correlated with specific genomic profiles. Numerous molecular aberrations were prognostic for disease recurrence, including several DNA methylation events, and a signature comprised of these aberrations outperformed well-described prognostic biomarkers. We suggest that intensified treatment of genomically aggressive localized prostate cancer may improve cure rates.


Assuntos
Genoma Humano/genética , Genômica , Mutação , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Cromotripsia , Variações do Número de Cópias de DNA , Metilação de DNA , Exoma/genética , Humanos , Masculino , Metástase Neoplásica/genética , Prognóstico , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia , Recidiva
2.
Rheumatology (Oxford) ; 61(3): 1092-1105, 2022 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-34175923

RESUMO

OBJECTIVE: We investigated the autoantibody (autoAb) profiles in ANA+ individuals lacking systemic autoimmune rheumatic disease (SARD) and early SARD patients to determine the key differences between these groups and identify factors that are associated with an increased risk of symptomatic progression within the next 2 years in ANA+ individuals. METHODS: Using custom antigen (Ag) microarrays, 144 IgM and IgG autoAbs were surveyed in 84 asymptomatic and 123 symptomatic (48 UCTD and 75 SARD patients) ANA+ individuals. AutoAbs were compared in ANA+ individuals lacking a SARD diagnosis with ≥2 years follow-up (n = 52), including all those who demonstrated progression (n = 14) during this period, with changes over time assessed in a representative subset. RESULTS: We show that ANA+ individuals have autoAb to many self-Ags that are not being captured by current screening techniques and very high levels of these autoAbs are predominantly restricted to early SARD patients, with SLE patients displaying reactivity to many more autoAgs than the other groups. In general, the symptoms that developed in progressors mirrored those seen in SARD patients with similar patterns of autoAbs. Only anti-Ro52 Abs were found to predict progression (positive predictive value 46%, negative predictive value 89%). Surprisingly, over 2 years of follow-up the levels of autoAbs remained remarkably stable regardless of whether individuals progressed or not. CONCLUSION: Our findings strongly argue that development of assays with an expanded set of auto-Ags and enhanced dynamic range would improve the diagnostic and prognostic ability of autoAb testing.


Assuntos
Anticorpos Antinucleares/sangue , Anticorpos Antinucleares/imunologia , Doenças Autoimunes/sangue , Doenças Autoimunes/imunologia , Doenças Reumáticas/sangue , Doenças Reumáticas/imunologia , Adulto , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Adulto Jovem
3.
Arch Toxicol ; 94(5): 1613-1624, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32277265

RESUMO

In rats, direct exposure to TCDD causes myriad toxicities. Exposed rats experience hepatotoxicity, wasting syndrome and immune suppression, amongst others. "Inherited exposure", as occurs in the F3 generation of directly exposed F0 animals, has also been shown to cause toxicity: both male and female F3 rats demonstrate an increased incidence of adult onset disease, females also display reproductive abnormalities and increased incidence of ovarian diseases while males show increased incidence of kidney disease and an altered sperm epigenome. Here, we explore the hepatic transcriptomic profile of male and female F3 Sprague-Dawley rats bred through the paternal germ line from F0 dams exposed to a single dose of TCDD (0, 30, 100, 300 or 1000 ng/kg body weight) by oral gavage. We hypothesize that RNA transcripts with altered abundance in livers of unexposed F3 progeny of treated F0 Sprague-Dawley rats may result from epigenetic modifications to the genome. We further survey patterns of differential methylation within male F3 rat testis. Female F3 rats demonstrated more TCDD-mediated hepatic transcriptomic changes than males, with differences primarily in the lowest dose group. In testis from male F3 rats, multiple olfactory receptors displayed patterns of differential methylation. Hypermethylation of Egfr and Mc5r among testes from TCDD lineage rats was observed, but without corresponding changes in hepatic mRNA abundance. Further studies examining these differences in other tissue types are warranted.


Assuntos
Poluentes Ambientais/toxicidade , Dibenzodioxinas Policloradas/toxicidade , Animais , Peso Corporal , Metilação de DNA , Epigênese Genética , Feminino , Genoma , Nefropatias , Masculino , Ratos , Ratos Sprague-Dawley , Espermatozoides , Testículo , Transcriptoma
4.
BMC Bioinformatics ; 20(1): 42, 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30665349

RESUMO

BACKGROUND: We introduce BPG, a framework for generating publication-quality, highly-customizable plots in the R statistical environment. RESULTS: This open-source package includes multiple methods of displaying high-dimensional datasets and facilitates generation of complex multi-panel figures, making it suitable for complex datasets. A web-based interactive tool allows online figure customization, from which R code can be downloaded for integration with computational pipelines. CONCLUSION: BPG provides a new approach for linking interactive and scripted data visualization and is available at http://labs.oicr.on.ca/boutros-lab/software/bpg or via CRAN at https://cran.r-project.org/web/packages/BoutrosLab.plotting.general.


Assuntos
Análise de Dados , Treinamento por Simulação/métodos , Humanos , Software
5.
Arch Toxicol ; 93(10): 2961-2978, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31511937

RESUMO

The aryl hydrocarbon receptor (AHR) mediates many toxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). However, the AHR alone does not explain the widely different outcomes among organisms. To identify the other factors involved, we evaluated three transgenic mouse lines, each expressing a different rat AHR isoform (rWT, DEL, and INS) providing widely different resistance to TCDD toxicity, as well as C57BL/6 and DBA/2 mice which exhibit a ~ tenfold divergence in TCDD sensitivity (exposures of 5-1000 µg/kg TCDD). We supplement these with whole-genome sequencing, together with transcriptomic and proteomic analyses of the corresponding rat models, Long-Evans (L-E) and Han/Wistar (H/W) rats (having a ~ 1000-fold difference in their TCDD sensitivities; 100 µg/kg TCDD), to identify genes associated with TCDD-response phenotypes. Overall, we identified up to 50% of genes with altered mRNA abundance following TCDD exposure are associated with a single AHR isoform (33.8%, 11.7%, 5.2% and 0.3% of 3076 genes altered unique to rWT, DEL, C57BL/6 and INS respectively following 1000 µg/kg TCDD). Hepatic Pxdc1 was significantly repressed in all three TCDD-sensitive animal models (C57BL/6 and rWT mice, and L-E rat) after TCDD exposure. Three genes, including Cxxc5, Sugp1 and Hgfac, demonstrated different AHRE-1 (full) motif occurrences within their promoter regions between rat strains, as well as different patterns of mRNA abundance. Several hepatic proteins showed parallel up- or downward alterations with their RNAs, with three genes (SNRK, IGTP and IMPA2) showing consistent, strain-dependent changes. These data show the value of integrating genomic, transcriptomic and proteomic evidence across multi-species models in toxicologic studies.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Poluentes Ambientais/toxicidade , Fígado/metabolismo , Dibenzodioxinas Policloradas/toxicidade , Receptores de Hidrocarboneto Arílico/genética , Animais , Relação Dose-Resposta a Droga , Poluentes Ambientais/administração & dosagem , Genômica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Transgênicos , Dibenzodioxinas Policloradas/administração & dosagem , Proteômica , RNA Mensageiro/genética , Ratos , Ratos Long-Evans , Ratos Wistar , Especificidade da Espécie , Transcriptoma
6.
Int J Mol Sci ; 20(6)2019 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-30893768

RESUMO

IMA-08401 (C2) is a novel aryl hydrocarbon receptor (AHR) agonist and selective AHR modulator (SAHRM) that is structurally similar to laquinimod (LAQ). Both compounds are converted to the AHR-active metabolite DELAQ (IMA-06201) in vivo. SAHRMs have been proposed as therapeutic options for various autoimmune disorders. Clinical trials on LAQ have not reported any significant toxic outcomes and C2 has shown low toxicity in rats; however, their functional resemblance to the highly toxic AHR agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) raises questions. Here, we characterize the hepatic transcriptomic changes induced by acute (single-dose) and subacute exposure (repeated dosing for 5 days followed by a 5-day recovery period) to C2 in Sprague-Dawley rats. Exposure to C2 leads to activation of the AHR, as shown by altered transcription of Cyp1a1. We identify a heightened response early after exposure that drops off by day 10. Acute exposure to C2 leads to changes to transcription of genes involved in antiviral and antibacterial responses, which highlights the immunomodulator effects of this AHR agonist. Subacute exposure causes an oxidative stress response in the liver, the consequences of which require further study on target tissues such as the CNS and immune system, both of which may be compromised in this patient population.


Assuntos
Fígado/metabolismo , Quinolonas/farmacologia , Transcriptoma/genética , Animais , Imunidade/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Dibenzodioxinas Policloradas/toxicidade , Ratos Sprague-Dawley , Transcriptoma/efeitos dos fármacos
7.
BMC Genomics ; 18(1): 78, 2017 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-28086803

RESUMO

BACKGROUND: 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is the most potent congener of the dioxin class of environmental contaminants. Exposure to TCDD causes a wide range of toxic outcomes, ranging from chloracne to acute lethality. The severity of toxicity is highly dependent on the aryl hydrocarbon receptor (AHR). Binding of TCDD to the AHR leads to changes in transcription of numerous genes. Studies evaluating the transcriptional changes brought on by TCDD may provide valuable insight into the role of the AHR in human health and disease. We therefore compiled a collection of transcriptomic datasets that can be used to aid the scientific community in better understanding the transcriptional effects of ligand-activated AHR. RESULTS: Specifically, we have created a datasets package - TCDD.Transcriptomics - for the R statistical environment, consisting of 63 unique experiments comprising 377 samples, including various combinations of 3 species (human derived cell lines, mouse and rat), 4 tissue types (liver, kidney, white adipose tissue and hypothalamus) and a wide range of TCDD exposure times and doses. These datasets have been fully standardized using consistent preprocessing and annotation packages (available as of September 14, 2015). To demonstrate the utility of this R package, a subset of "AHR-core" genes were evaluated across the included datasets. Ahrr, Nqo1 and members of the Cyp family were significantly induced following exposure to TCDD across the studies as expected while Aldh3a1 was induced specifically in rat liver. Inmt was altered only in liver tissue and primarily by rat-AHR. CONCLUSIONS: Analysis of the "AHR-core" genes demonstrates a continued need for studies surrounding the impact of AHR-activity on the transcriptome; genes believed to be consistently regulated by ligand-activated AHR show surprisingly little overlap across species and tissues. Until now, a comprehensive assessment of the transcriptome across these studies was challenging due to differences in array platforms, processing methods and annotation versions. We believe that this package, which is freely available for download ( http://labs.oicr.on.ca/boutros-lab/tcdd-transcriptomics ) will prove to be a highly beneficial resource to the scientific community evaluating the effects of TCDD exposure as well as the variety of functions of the AHR.


Assuntos
Poluentes Ambientais/farmacologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Dibenzodioxinas Policloradas/farmacologia , Transcriptoma , Animais , Linhagem Celular , Biologia Computacional/métodos , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Masculino , Camundongos , Ratos , Software , Navegador
8.
Arch Toxicol ; 91(1): 325-338, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27136898

RESUMO

2,3,7,8 Tetrachlorodibenzo-p-dioxin (TCDD) is an aromatic, long-lived environmental contaminant. While the pathogenesis of TCDD-induced toxicity is poorly understood, it has been shown that the aryl hydrocarbon receptor (AHR) is required. However, the specific transcriptomic changes that lead to toxic outcomes have not yet been identified. We previously identified a panel of 33 genes that respond to TCDD treatment in two TCDD-sensitive rodent species. To identify genes involved in the onset of hepatic toxicity, we explored 25 of these in-depth using liver from two rat strains: the TCDD-resistant Han/Wistar (H/W) and the TCDD-sensitive Long-Evans (L-E). Time course and dose-response analyses of mRNA abundance following TCDD insult indicate that eight genes are similarly regulated in livers of both strains of rat, suggesting that they are not central to the severe L-E-specific TCDD-induced toxicities. The remaining 17 genes exhibited various divergent mRNA abundances between L-E and H/W strains after TCDD treatment. Several genes displayed a biphasic response where the initial response to TCDD treatment was followed by a secondary response, usually of larger magnitude in L-E liver. This secondary response was most often an exaggeration of the original TCDD-induced response. Only cytochrome b5 type A (microsomal) (Cyb5a) had equivalent TCDD sensitivity to the prototypic AHR-responsive cytochrome P450, family 1, subfamily a, polypeptide 1 (Cyp1a1), while six genes were less sensitive. Four genes showed an early inter-strain difference that was sustained throughout most of the time course (atypical chemokine receptor 3 (Ackr3), collagen, type XVIII, alpha 1 (Col18a1), Cyb5a and glutamate dehydrogenase 1 (Glud1)), and of those genes examined in this study, are most likely to represent genes involved in the pathogenesis of TCDD-induced hepatotoxicity in L-E rats.


Assuntos
Carcinógenos Ambientais/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Fígado/efeitos dos fármacos , Dibenzodioxinas Policloradas/toxicidade , RNA Mensageiro/metabolismo , Animais , Animais não Endogâmicos , Carcinógenos Ambientais/administração & dosagem , Doença Hepática Induzida por Substâncias e Drogas/enzimologia , Colágeno Tipo VIII/agonistas , Colágeno Tipo VIII/antagonistas & inibidores , Colágeno Tipo VIII/genética , Colágeno Tipo VIII/metabolismo , Citocromos b5/antagonistas & inibidores , Citocromos b5/química , Citocromos b5/genética , Citocromos b5/metabolismo , Relação Dose-Resposta a Droga , Resistência a Medicamentos , Feminino , Perfilação da Expressão Gênica , Glutamato Desidrogenase , Cinética , Fígado/enzimologia , Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Dibenzodioxinas Policloradas/administração & dosagem , Ratos Long-Evans , Receptores CXCR/agonistas , Receptores CXCR/antagonistas & inibidores , Receptores CXCR/genética , Receptores CXCR/metabolismo , Receptores de Glutamato/química , Receptores de Glutamato/genética , Receptores de Glutamato/metabolismo
9.
BMC Bioinformatics ; 17(1): 401, 2016 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-27716034

RESUMO

BACKGROUND: Visualization of data generated by high-throughput, high-dimensionality experiments is rapidly becoming a rate-limiting step in computational biology. There is an ongoing need to quickly develop high-quality visualizations that can be easily customized or incorporated into automated pipelines. This often requires an interface for manual plot modification, rapid cycles of tweaking visualization parameters, and the generation of graphics code. To facilitate this process for the generation of highly-customizable, high-resolution Venn and Euler diagrams, we introduce VennDiagramWeb: a web application for the widely used VennDiagram R package. VennDiagramWeb is hosted at http://venndiagram.res.oicr.on.ca/ . RESULTS: VennDiagramWeb allows real-time modification of Venn and Euler diagrams, with parameter setting through a web interface and immediate visualization of results. It allows customization of essentially all aspects of figures, but also supports integration into computational pipelines via download of R code. Users can upload data and download figures in a range of formats, and there is exhaustive support documentation. CONCLUSIONS: VennDiagramWeb allows the easy creation of Venn and Euler diagrams for computational biologists, and indeed many other fields. Its ability to support real-time graphics changes that are linked to downloadable code that can be integrated into automated pipelines will greatly facilitate the improved visualization of complex datasets. For application support please contact Paul.Boutros@oicr.on.ca.


Assuntos
Biologia Computacional/métodos , Gráficos por Computador , Interpretação Estatística de Dados , Software , Documentação , Humanos , Internet , Interface Usuário-Computador
10.
BMC Genomics ; 16: 625, 2015 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-26290441

RESUMO

BACKGROUND: 2,3,7,8-tetrachlorodibenzo-p-dixion (TCDD) is the most potent of the dioxin congeners, capable of causing a wide range of toxic effects across numerous animal models. Previous studies have demonstrated that males and females of the same species can display divergent sensitivity phenotypes to TCDD toxicities. Although it is now clear that most TCDD-induced toxic outcomes are mediated by the aryl hydrocarbon receptor (AHR), the mechanism of differential responses to TCDD exposure between sexes remains largely unknown. To investigate the differential sensitivities in male and female mice, we profiled the hepatic transcriptomic responses 4 days following exposure to various amounts of TCDD (125, 250, 500 or 1000 µg/kg) in adult male and female C57BL/6Kuo mice. RESULTS: Several key findings were revealed by our study. 1) Hepatic transcriptomes varied significantly between the sexes at all doses examined. 2) The liver transcriptome of males was more dysregulated by TCDD than that of females. 3) The alteration of "AHR-core" genes was consistent in magnitude, regardless of sex. 4) A subset of genes demonstrated sex-dependent TCDD-induced transcriptional changes, including Fmo3 and Nr1i3, which were significantly induced in livers of male mice only. In addition, a meta-analysis was performed to contrast transcriptomic profiles of various organisms and tissues following exposure to equitoxic doses of TCDD. Minimal overlap was observed in the differences between TCDD-sensitive or TCDD-resistant models. CONCLUSIONS: Sex-dependent sensitivities to TCDD exposure are associated with a set of sex-specific TCDD-responsive genes. In addition, complex interactions between the aryl hydrocarbon and sex hormone receptors may affect the observable differences in sensitivity phenotypes between the sexes. Further work is necessary to better understand the roles of those genes altered by TCDD in a sex-dependent manner, and their association with changes to sex hormones and receptors.


Assuntos
Fígado/efeitos dos fármacos , Dibenzodioxinas Policloradas/toxicidade , Transcriptoma/efeitos dos fármacos , Animais , Receptor Constitutivo de Androstano , Feminino , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos , Dibenzodioxinas Policloradas/administração & dosagem , Receptores Citoplasmáticos e Nucleares/genética , Fatores Sexuais
11.
RNA ; 19(1): 51-62, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23169800

RESUMO

Profiling of mRNA abundances with high-throughput platforms such as microarrays and RNA-seq has become an important tool in both basic and biomedical research. However, these platforms remain prone to systematic errors and have challenges in clinical and industrial applications. As a result, it is standard practice to validate a subset of key results using alternate technologies. Similarly, clinical and industrial applications typically involve transitions from a high-throughput discovery platform to medium-throughput validation ones. These medium-throughput validation platforms have high technical reproducibility and reduced sample input needs, and low sensitivity to sample quality (e.g., for processing FFPE specimens). Unfortunately, while medium-throughput platforms have proliferated, there are no comprehensive comparisons of them. Here we fill that gap by comparing two key medium-throughput platforms--NanoString's nCounter Analysis System and ABI's OpenArray System--to gold-standard quantitative real-time RT-PCR. We quantified 38 genes and positive and negative controls in 165 samples. Signal:noise ratios, correlations, dynamic range, and detection accuracy were compared across platforms. All three measurement technologies showed good concordance, but with divergent price/time/sensitivity trade-offs. This study provides the first detailed comparison of medium-throughput RNA quantification platforms and provides a template and a standard data set for the evaluation of additional technologies.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , RNA Mensageiro/análise , Reação em Cadeia da Polimerase em Tempo Real/métodos , Animais , Perfilação da Expressão Gênica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/economia , Sequenciamento de Nucleotídeos em Larga Escala/instrumentação , Masculino , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Dibenzodioxinas Policloradas/toxicidade , RNA Mensageiro/efeitos dos fármacos , Ratos , Ratos Long-Evans , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real/economia , Reação em Cadeia da Polimerase em Tempo Real/instrumentação , Reprodutibilidade dos Testes , Razão Sinal-Ruído
12.
Rheumatology (Oxford) ; 54(3): 449-57, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25193804

RESUMO

OBJECTIVE: The aim of this study was to determine whether anti-nucleosome antibodies function as activity-specific biomarkers in SLE. METHODS: Fifty-one patients were recruited and followed prospectively with periodic clinical and biochemical assessments over a 14-month period. Disease activity was determined by the SLEDAI-2K. Anti-nucleosome antibody levels were measured by an ELISA and its utility as an activity-specific biomarker as compared with that of anti-dsDNA antibodies and C3 was assessed both at baseline and in longitudinal analysis. RESULTS: Anti-nucleosome antibodies were significantly elevated in SLE patients vs controls and showed a moderate positive correlation with disease activity. The utility of anti-nucleosome antibodies in identifying patients with active disease in a cross-sectional analysis was comparable to that of anti-dsDNA antibodies and C3. Analysis of variance demonstrated that the level of anti-nucleosome antibodies and C3 varied significantly with changes in disease activity over time. Changes in clinical state were not mirrored by changes in anti-dsDNA antibodies. In time-dependent analysis, anti-nucleosome antibodies showed a better fit over time than anti-dsDNA antibodies and C3. In pairwise comparisons, C3 and anti-nucleosome antibodies outperformed other models, including the conventional pairing of C3 and anti-dsDNA antibodies, however, no biomarker alone or as a group accurately predicted impending remissions or exacerbations. CONCLUSION: Anti-nucleosome antibodies demonstrate greater fidelity as a biomarker for changes in SLE disease activity than traditional biomarkers, supporting the routine monitoring of this antibody in clinical practice.


Assuntos
Anticorpos Anti-Idiotípicos/sangue , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/diagnóstico , Nucleossomos/imunologia , Índice de Gravidade de Doença , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Complemento C3/metabolismo , Estudos Transversais , DNA/imunologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Fatores de Tempo , Adulto Jovem
13.
Toxicol Appl Pharmacol ; 284(2): 188-96, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25703434

RESUMO

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is an environmental contaminant that produces myriad toxicities in most mammals. In rodents alone, there is a huge divergence in the toxicological response across species, as well as among different strains within a species. But there are also significant differences between males and females animals of a single strain. These differences are inconsistent across model systems: the severity of toxicity is greater in female rats than males, while male mice and guinea pigs are more sensitive than females. Because the specific events that underlie this difference remain unclear, we characterized the hepatic transcriptional response of adult male and female C57BL/6 mice to 500µg/kg TCDD at multiple time-points. The transcriptional profile diverged significantly between the sexes. Female mice demonstrated a large number of altered transcripts as early as 6h following treatment, suggesting a large primary response. Conversely, male animals showed the greatest TCDD-mediated response 144h following exposure, potentially implicating significant secondary responses. Nr1i3 was statistically significantly induced at all time-points in the sensitive male animals. This mRNA encodes the constitutive androstane receptor (CAR), a transcription factor involved in the regulation of xenobiotic metabolism, lipid metabolism, cell cycle and apoptosis. Surprisingly though, changes at the protein level (aside from the positive control, CYP1A1) were modest, with only FMO3 showing clear induction, and no genes with sex-differences. Thus, while male and female mice show transcriptional differences in their response to TCDD, their association with TCDD-induced toxicities remains unclear.


Assuntos
Dibenzodioxinas Policloradas/toxicidade , Proteoma/efeitos dos fármacos , Proteoma/genética , Transcrição Gênica/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Receptor Constitutivo de Androstano , Poluentes Ambientais/toxicidade , Feminino , Cobaias , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteômica/métodos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Fatores Sexuais , Fatores de Transcrição/genética
14.
Toxicol Appl Pharmacol ; 288(2): 223-31, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26232522

RESUMO

Polychlorinated dibenzodioxins are environmental contaminants commonly produced as a by-product of industrial processes. The most potent of these, 2,3,7,8-tetrachlorodibenzo-ρ-dioxin (TCDD), is highly lipophilic, leading to bioaccumulation. White adipose tissue (WAT) is a major site for energy storage, and is one of the organs in which TCDD accumulates. In laboratory animals, exposure to TCDD causes numerous metabolic abnormalities, including a wasting syndrome. We therefore investigated the molecular effects of TCDD exposure on WAT by profiling the transcriptomic response of WAT to 100µg/kg of TCDD at 1 or 4days in TCDD-sensitive Long-Evans (Turku/AB; L-E) rats. A comparative analysis was conducted simultaneously in identically treated TCDD-resistant Han/Wistar (Kuopio; H/W) rats one day after exposure to the same dose. We sought to identify transcriptomic changes coinciding with the onset of toxicity, while gaining additional insight into later responses. More transcriptional responses to TCDD were observed at 4days than at 1day post-exposure, suggesting WAT shows mostly secondary responses. Two classic AHR-regulated genes, Cyp1a1 and Nqo1, were significantly induced by TCDD in both strains, while several genes involved in the immune response, including Ms4a7 and F13a1 were altered in L-E rats alone. We compared genes affected by TCDD in rat WAT and human adipose cells, and observed little overlap. Interestingly, very few genes involved in lipid metabolism exhibited altered expression levels despite the pronounced lipid mobilization from peripheral fat pads by TCDD in L-E rats. Of these genes, the lipolysis-associated Lpin1 was induced slightly over 2-fold in L-E rat WAT on day 4.


Assuntos
Tecido Adiposo Branco/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Perfilação da Expressão Gênica , Dibenzodioxinas Policloradas/toxicidade , Transcrição Gênica/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Animais , Restrição Calórica , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Humanos , Masculino , Ratos Long-Evans , Ratos Wistar , Especificidade da Espécie , Fatores de Tempo
15.
BMC Genomics ; 15: 1053, 2014 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-25467400

RESUMO

BACKGROUND: Research on the aryl hydrocarbon receptor (AHR) has largely focused on variations in toxic outcomes resulting from its activation by halogenated aromatic hydrocarbons. But the AHR also plays key roles in regulating pathways critical for development, and after decades of research the mechanisms underlying physiological regulation by the AHR remain poorly characterized. Previous studies identified several core genes that respond to xenobiotic AHR ligands across a broad range of species and tissues. However, only limited inferences have been made regarding its role in regulating constitutive gene activity, i.e. in the absence of exogenous ligands. To address this, we profiled transcriptomic variations between AHR-active and AHR-less-active animals in the absence of an exogenous agonist across five tissues, three of which came from rats (hypothalamus, white adipose and liver) and two of which came from mice (kidney and liver). Because AHR status alone has been shown sufficient to alter transcriptomic responses, we reason that by contrasting profiles amongst AHR-variant animals, we may elucidate effects of the AHR on constitutive mRNA abundances. RESULTS: We found significantly more overlap in constitutive mRNA abundances amongst tissues within the same species than from tissues between species and identified 13 genes (Agt, Car3, Creg1, Ctsc, E2f6, Enpp1, Gatm, Gstm4, Kcnj8, Me1, Pdk1, Slc35a3, and Sqrdl) that are affected by AHR-status in four of five tissues. One gene, Creg1, was significantly up-regulated in all AHR-less-active animals. We also find greater overlap between tissues at the pathway level than at the gene level, suggesting coherency to the AHR signalling response within these processes. Analysis of regulatory motifs suggests that the AHR mostly mediates transcriptional regulation via direct binding to response elements. CONCLUSIONS: These findings, though preliminary, present a platform for further evaluating the role of the AHR in regulation of constitutive mRNA levels and physiologic function.


Assuntos
Perfilação da Expressão Gênica , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Transcriptoma , Animais , Análise por Conglomerados , Biologia Computacional , Regulação da Expressão Gênica , Masculino , Camundongos , Especificidade de Órgãos , Ligação Proteica , Ratos , Transdução de Sinais , Especificidade da Espécie
16.
Toxicol Appl Pharmacol ; 274(3): 445-54, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24355419

RESUMO

Despite several decades of research, the complete mechanism by which 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and other xenobiotic agonists of the aryl hydrocarbon receptor (AHR) cause toxicity remains unclear. While it has been shown that the AHR is required for all major manifestations of toxicity, the specific downstream changes involved in the development of toxic phenotypes remain unknown. Here we examine a panel of 13 genes that are AHR-regulated in many species and tissues. We profiled their hepatic mRNA abundances in two rat strains with very different sensitivities to TCDD: the TCDD-sensitive Long-Evans (Turku/AB; L-E) and the TCDD-resistant Han/Wistar (Kuopio; H/W). We evaluated doses ranging from 0 to 3000µg/kg at 19h after TCDD exposure and time points ranging from 1.5 to 384h after exposure to 100µg/kg TCDD. Twelve of 13 genes responded to TCDD in at least one strain, and seven of these showed statistically significant inter-strain differences in the time course analysis (Aldh3a1, Cyp1a2, Cyp1b1, Cyp2a1, Fmo1, Nfe2l2 and Nqo1). Cyp2s1 did not respond to TCDD in either rat strain. Five genes exhibited biphasic responses to TCDD insult (Ahrr, Aldh3a1, Cyp1b1, Nfe2l2 and Nqo1), suggesting a secondary event, such as association with additional transcriptional modulators. Of the 12 genes that responded to TCDD during the dose-response analysis, none had an ED50 equivalent to that of Cyp1a1, the most sensitive gene in this study, while nine genes responded to doses at least 10-100 fold higher, in at least one strain (Ahrr (L-E), Aldh3a1 (both), Cyp1a2 (both), Cyp1b1 (both), Cyp2a1 (L-E), Inmt (both), Nfe2l2 (L-E), Nqo1 (L-E) and Tiparp (both)). These data shed new light on the association of the AHR target genes with TCDD toxicity, and in particular the seven genes exhibiting strain-specific differences represent strong candidate mediators of Type-II toxicities.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Fígado/efeitos dos fármacos , Dibenzodioxinas Policloradas/toxicidade , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Hidrocarboneto de Aril Hidroxilases/genética , Hidrocarboneto de Aril Hidroxilases/metabolismo , Citocromo P-450 CYP1A2 , Citocromo P-450 CYP1B1 , Família 2 do Citocromo P450 , Citocromos/genética , Citocromos/metabolismo , Relação Dose-Resposta a Droga , Fígado/metabolismo , Masculino , NAD(P)H Desidrogenase (Quinona)/genética , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Long-Evans , Ratos Wistar , Esteroide Hidroxilases/genética , Esteroide Hidroxilases/metabolismo , Xenobióticos/toxicidade
17.
Cancer Discov ; 14(1): 104-119, 2024 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-37874259

RESUMO

People with Li-Fraumeni syndrome (LFS) harbor a germline pathogenic variant in the TP53 tumor suppressor gene, face a near 100% lifetime risk of cancer, and routinely undergo intensive surveillance protocols. Liquid biopsy has become an attractive tool for a range of clinical applications, including early cancer detection. Here, we provide a proof-of-principle for a multimodal liquid biopsy assay that integrates a targeted gene panel, shallow whole-genome, and cell-free methylated DNA immunoprecipitation sequencing for the early detection of cancer in a longitudinal cohort of 89 LFS patients. Multimodal analysis increased our detection rate in patients with an active cancer diagnosis over uni-modal analysis and was able to detect cancer-associated signal(s) in carriers prior to diagnosis with conventional screening (positive predictive value = 67.6%, negative predictive value = 96.5%). Although adoption of liquid biopsy into current surveillance will require further clinical validation, this study provides a framework for individuals with LFS. SIGNIFICANCE: By utilizing an integrated cell-free DNA approach, liquid biopsy shows earlier detection of cancer in patients with LFS compared with current clinical surveillance methods such as imaging. Liquid biopsy provides improved accessibility and sensitivity, complementing current clinical surveillance methods to provide better care for these patients. See related commentary by Latham et al., p. 23. This article is featured in Selected Articles from This Issue, p. 5.


Assuntos
Ácidos Nucleicos Livres , Síndrome de Li-Fraumeni , Humanos , Síndrome de Li-Fraumeni/diagnóstico , Síndrome de Li-Fraumeni/genética , Síndrome de Li-Fraumeni/patologia , Proteína Supressora de Tumor p53/genética , Detecção Precoce de Câncer , Ácidos Nucleicos Livres/genética , Genes p53 , Mutação em Linhagem Germinativa , Predisposição Genética para Doença
18.
Cell Rep ; 43(3): 113826, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38412093

RESUMO

Anaplastic thyroid carcinoma is arguably the most lethal human malignancy. It often co-occurs with differentiated thyroid cancers, yet the molecular origins of its aggressivity are unknown. We sequenced tumor DNA from 329 regions of thyroid cancer, including 213 from patients with primary anaplastic thyroid carcinomas. We also whole genome sequenced 9 patients using multi-region sequencing of both differentiated and anaplastic thyroid cancer components. Using these data, we demonstrate thatanaplastic thyroid carcinomas have a higher burden of mutations than other thyroid cancers, with distinct mutational signatures and molecular subtypes. Further, different cancer driver genes are mutated in anaplastic and differentiated thyroid carcinomas, even those arising in a single patient. Finally, we unambiguously demonstrate that anaplastic thyroid carcinomas share a genomic origin with co-occurring differentiated carcinomas and emerge from a common malignant field through acquisition of characteristic clonal driver mutations.


Assuntos
Adenocarcinoma , Carcinoma Anaplásico da Tireoide , Neoplasias da Glândula Tireoide , Humanos , Carcinoma Anaplásico da Tireoide/genética , Carcinoma Anaplásico da Tireoide/patologia , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Mutação/genética , Genômica
19.
Kidney Int ; 84(6): 1246-53, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23760288

RESUMO

Animal studies suggest temporary renin-angiotensin system (RAS) blockade enhances long-term vascular protective effects; however, this is not established in humans. Here we evaluated the long-term effects of prior RAS blockade on hemodynamic function, urinary measures of inflammation, and tissue antioxidant mRNA expression in patients with type 1 diabetes mellitus (T1DM) who participated in the 5-year Renin Angiotensin System Study (RASS). At 4 years after completing the RASS and discontinuing study medication, renal hemodynamic responses to clamped hyperglycemia were significantly greater in 18 patients in the RAS blockade group compared to 9 patients of the placebo-treated group. Individuals who had received RAS blockade also exhibited higher flow-mediated vasodilatation, reduced urinary cytokine excretion in response to hyperglycemia, and increased skin mRNA expression of superoxide dismutase-1 and catalase. Thus, patients with uncomplicated T1DM who received prior RAS blockade for 5 years maintain long-term effects on renal hemodynamic and systemic vascular function, inflammatory pathways in the kidney, and antioxidant enzyme expression in skin 4 years after discontinuation of therapy. Our findings suggest that sustained long-term protective effects of finite RAS inhibition requires further study.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Diabetes Mellitus Tipo 1/tratamento farmacológico , Angiopatias Diabéticas/prevenção & controle , Enalapril/administração & dosagem , Hemodinâmica/efeitos dos fármacos , Losartan/administração & dosagem , Sistema Renina-Angiotensina/efeitos dos fármacos , Adulto , Quimiocinas/urina , Citocinas/urina , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/fisiopatologia , Angiopatias Diabéticas/diagnóstico , Angiopatias Diabéticas/metabolismo , Angiopatias Diabéticas/fisiopatologia , Esquema de Medicação , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ontário , Estresse Oxidativo/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/enzimologia , Fatores de Tempo , Resultado do Tratamento , Rigidez Vascular/efeitos dos fármacos
20.
Oral Oncol ; 146: 106580, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37778229

RESUMO

OBJECTIVES: Although human papillomavirus positive (HPV+) oropharyngeal squamous cell carcinoma (OPSCC) patients typically experience excellent survival, 15-20 % of patients recur after treatment with chemotherapy and radiation. Therefore, there is a need for biomarkers of treatment failure to guide treatment intensity. MATERIALS AND METHODS: Whole genome sequencing was carried out on HPV+OPSCC patients who were primarily treated with concurrent chemotherapy (cisplatin) and radiation. We then explored whether the loss of LRP1Bwas sufficient to drive an aggressive phenotype, and promote a resistance to cisplatin and radiation therapy both in vitro using HPV+ cell lines (93VU147T, UMSCC47, UWO37 and UWO23) and in vivo. RESULTS: Through integrative genomic analysis of three HPV+OPSCC tumour datasets, we identified that deletion of LRP1B was enriched in samples that recurred following chemo-radiation. Knockdown using siRNA in four HPV+ cell lines (UWO23, UWO37, UMSCC47 and 93VU147T) resulted in increased proliferation of all cases. CRISPR/Cas9 deletion of LRP1B in the same cell line panel demonstrated increased proliferation, clonogenic growth and migration, as well as resistance to both cisplatin and radiation in LRP1B deleted cells compared to their respective non-targeting control cells. Cell line derived xenograft studies indicated that the LRP1B knockout tumours were more resistant to cisplatin and radiation therapy compared to their controls invivo. CONCLUSION: Taken together, our work implicates LRP1B deletion as a potential biomarker for identifying treatment resistant HPV+ OPSCC cases.


Assuntos
Carcinoma de Células Escamosas , Resistencia a Medicamentos Antineoplásicos , Neoplasias de Cabeça e Pescoço , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Tolerância a Radiação , Humanos , Carcinoma de Células Escamosas/patologia , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/radioterapia , Recidiva Local de Neoplasia , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/patologia , Receptores de LDL/uso terapêutico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia
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