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1.
Cancer Res ; 81(7): 1667-1680, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33558336

RESUMO

Insights into oncogenesis derived from cancer susceptibility loci (SNP) hold the potential to facilitate better cancer management and treatment through precision oncology. However, therapeutic insights have thus far been limited by our current lack of understanding regarding both interactions of these loci with somatic cancer driver mutations and their influence on tumorigenesis. For example, although both germline and somatic genetic variation to the p53 tumor suppressor pathway are known to promote tumorigenesis, little is known about the extent to which such variants cooperate to alter pathway activity. Here we hypothesize that cancer risk-associated germline variants interact with somatic TP53 mutational status to modify cancer risk, progression, and response to therapy. Focusing on a cancer risk SNP (rs78378222) with a well-documented ability to directly influence p53 activity as well as integration of germline datasets relating to cancer susceptibility with tumor data capturing somatically-acquired genetic variation provided supportive evidence for this hypothesis. Integration of germline and somatic genetic data enabled identification of a novel entry point for therapeutic manipulation of p53 activities. A cluster of cancer risk SNPs resulted in increased expression of prosurvival p53 target gene KITLG and attenuation of p53-mediated responses to genotoxic therapies, which were reversed by pharmacologic inhibition of the prosurvival c-KIT signal. Together, our results offer evidence of how cancer susceptibility SNPs can interact with cancer driver genes to affect cancer progression and identify novel combinatorial therapies. SIGNIFICANCE: These results offer evidence of how cancer susceptibility SNPs can interact with cancer driver genes to affect cancer progression and present novel therapeutic targets.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias/genética , Neoplasias/patologia , Proteína Supressora de Tumor p53/genética , Animais , Antineoplásicos/uso terapêutico , Biomarcadores Farmacológicos/metabolismo , Carcinogênese/genética , Estudos de Casos e Controles , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Mutação em Linhagem Germinativa/fisiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mutação de Sentido Incorreto , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Polimorfismo de Nucleotídeo Único/fisiologia , Prognóstico , Fatores de Risco , Transdução de Sinais/genética , Resultado do Tratamento
2.
J Med Genet ; 58(6): 392-399, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32591342

RESUMO

BACKGROUND: Height and other anthropometric measures are consistently found to associate with differential cancer risk. However, both genetic and mechanistic insights into these epidemiological associations are notably lacking. Conversely, inherited genetic variants in tumour suppressors and oncogenes increase cancer risk, but little is known about their influence on anthropometric traits. METHODS: By integrating inherited and somatic cancer genetic data from the Genome-Wide Association Study Catalog, expression Quantitative Trait Loci databases and the Cancer Gene Census, we identify SNPs that associate with different cancer types and differential gene expression in at least one tissue type, and explore the potential pleiotropic associations of these SNPs with anthropometric traits through SNP-wise association in a cohort of 500,000 individuals. RESULTS: We identify three regulatory SNPs for three important cancer genes, FANCA, MAP3K1 and TP53 that associate with both anthropometric traits and cancer risk. Of particular interest, we identify a previously unrecognised strong association between the rs78378222[C] SNP in the 3' untranslated region (3'-UTR) of TP53 and both increased risk for developing non-melanomatous skin cancer (OR=1.36 (95% 1.31 to 1.41), adjusted p=7.62E-63), brain malignancy (OR=3.12 (2.22 to 4.37), adjusted p=1.43E-12) and increased standing height (adjusted p=2.18E-24, beta=0.073±0.007), lean body mass (adjusted p=8.34E-37, beta=0.073±0.005) and basal metabolic rate (adjusted p=1.13E-31, beta=0.076±0.006), thus offering a novel genetic link between these anthropometric traits and cancer risk. CONCLUSION: Our results clearly demonstrate that heritable variants in key cancer genes can associate with both differential cancer risk and anthropometric traits in the general population, thereby lending support for a genetic basis for linking these human phenotypes.


Assuntos
Pesos e Medidas Corporais , Neoplasias/genética , Oncogenes , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Antropometria , Estudos de Coortes , Feminino , Ligação Genética , Pleiotropia Genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Locos de Características Quantitativas , Característica Quantitativa Herdável , Medição de Risco
3.
Oncotarget ; 8(18): 30328-30343, 2017 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-28416760

RESUMO

The lysine demethylase 3A (KDM3A, JMJD1A or JHDM2A) controls transcriptional networks in a variety of biological processes such as spermatogenesis, metabolism, stem cell activity, and tumor progression. We matched transcriptomic and ChIP-Seq profiles to decipher a genome-wide regulatory network of epigenetic control by KDM3A in prostate cancer cells. ChIP-Seq experiments monitoring histone 3 lysine 9 (H3K9) methylation marks show global histone demethylation effects of KDM3A. Combined assessment of histone demethylation events and gene expression changes presented major transcriptional activation suggesting that distinct oncogenic regulators may synergize with the epigenetic patterns by KDM3A. Pathway enrichment analysis of cells with KDM3A knockdown prioritized androgen signaling indicating that KDM3A plays a key role in regulating androgen receptor activity. Matched ChIP-Seq and knockdown experiments of KDM3A in combination with ChIP-Seq of the androgen receptor resulted in a gain of H3K9 methylation marks around androgen receptor binding sites of selected transcriptional targets in androgen signaling including positive regulation of KRT19, NKX3-1, KLK3, NDRG1, MAF, CREB3L4, MYC, INPP4B, PTK2B, MAPK1, MAP2K1, IGF1, E2F1, HSP90AA1, HIF1A, and ACSL3. The cancer systems biology analysis of KDM3A-dependent genes identifies an epigenetic and transcriptional network in androgen response, hypoxia, glycolysis, and lipid metabolism. Genome-wide ChIP-Seq data highlights specific gene targets and the ability of epigenetic master regulators to control oncogenic pathways and cancer progression.


Assuntos
Regulação Neoplásica da Expressão Gênica , Histona Desmetilases com o Domínio Jumonji/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Transcrição Gênica , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Biologia Computacional/métodos , Ativação Enzimática , Epigênese Genética , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Redes Reguladoras de Genes , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Histonas/metabolismo , Humanos , Masculino , Metilação , Anotação de Sequência Molecular , Ligação Proteica , Transdução de Sinais
4.
Free Radic Biol Med ; 79: 206-16, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25451639

RESUMO

Inducible nitric oxide synthase (iNOS) is a key enzyme in the macrophage inflammatory response, which is the source of nitric oxide (NO) that is potently induced in response to proinflammatory stimuli. However, the specific role of NO production, as distinct from iNOS induction, in macrophage inflammatory responses remains unproven. We have generated a novel mouse model with conditional deletion of Gch1, encoding GTP cyclohydrolase 1 (GTPCH), an essential enzyme in the biosynthesis of tetrahydrobiopterin (BH4) that is a required cofactor for iNOS NO production. Mice with a floxed Gch1 allele (Gch1(fl/fl)) were crossed with Tie2cre transgenic mice, causing Gch1 deletion in leukocytes (Gch1(fl/fl)Tie2cre). Macrophages from Gch1(fl/fl)Tie2cre mice lacked GTPCH protein and de novo biopterin biosynthesis. When activated with LPS and IFNγ, macrophages from Gch1(fl/fl)Tie2cre mice induced iNOS protein in a manner indistinguishable from wild-type controls, but produced no detectable NO, as judged by L-citrulline production, EPR spin trapping of NO, and by nitrite accumulation. Incubation of Gch1(fl/fl)Tie2cre macrophages with dihydroethidium revealed significantly increased production of superoxide in the presence of iNOS expression, and an iNOS-independent, BH4-dependent increase in other ROS species. Normal BH4 levels, nitric oxide production, and cellular redox state were restored by sepiapterin, a precursor of BH4 production by the salvage pathway, demonstrating that the effects of BH4 deficiency were reversible. Gch1(fl/fl)Tie2cre macrophages showed only minor alterations in cytokine production and normal cell migration, and minimal changes in basal gene expression. However, gene expression analysis after iNOS induction identified 78 genes that were altered between wild-type and Gch1(fl/fl)Tie2cre macrophages. Pathway analysis identified decreased NRF2 activation, with reduced induction of archetypal NRF2 genes (gclm, prdx1, gsta3, nqo1, and catalase) in BH4-deficient Gch1(fl/fl)Tie2cre macrophages. These findings identify BH4-dependent iNOS regulation and NO generation as specific requirements for NRF2-dependent responses in macrophage inflammatory activation.


Assuntos
Biopterinas/análogos & derivados , GTP Cicloidrolase/genética , Macrófagos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Animais , Biopterinas/deficiência , Biopterinas/metabolismo , Macrófagos/enzimologia , Camundongos , Óxido Nítrico/metabolismo , Oxirredução
5.
Rapid Commun Mass Spectrom ; 27(21): 2493-503, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24097406

RESUMO

RATIONALE: The consumption of red meat is known to enhance the endogenous formation of N-nitroso compounds (NOCs), which are potent carcinogens. DNA damage related to NOCs, and hence red meat, has been detected in colorectal cells and in blood. We proposed to extend previous studies to a non-invasive approach for the detection of O(6)-carboxymethylguanine (O(6)CMG) and O(6)-carboxymethyl-2'-deoxyguanosine (O(6)CMdG) in urine in relation to red meat intake using liquid chromatography/tandem mass spectrometry (LC/MS/MS). The presence of the adduct in urine samples either as the free base or as 2'-deoxynucleoside could help in determining the repair mechanism involved when such lesions are produced. A non-invasive assessment of DNA adducts could also allow for large-scale analyses in the population and cancer prevention dietary strategies. METHODS: An LC/MS/MS method for the quantitation of O(6)CMG and O(6)CMdG was developed. Urine samples collected from healthy volunteers on red meat and vegetarian diets were analysed either by direct injection or after purification by solid-phase extraction (SPE). A separate LC/MS/MS method for O(6)-methylguanine (O(6)MeG) and O(6)-methyl-2'-deoxyguanosine (O(6)MedG), which are possible hydrolysis products forming during the sample pre-treatment, was also developed. RESULTS: The developed LC/MS/MS method allowed the simultaneous measurement of O(6)CMG and O(6)CMdG. The limits of detection (LODs) were 0.38 ng/mL for O(6)CMG and 0.18 ng/mL for O(6)CMdG. The direct injection analysis of the clinical samples showed low sensitivity due to high background signal that was improved by SPE purification. However, the concentrations of the adducts in clinical samples were still found to be below the LOD. CONCLUSIONS: Novel, reproducible, and accurate LC/MS/MS methods were developed for the determination of the urinary content of O(6)CMG and O(6)CMdG, and of the possible formation of O(6)MeG and O(6)MedG by decarboxylation. Clinical samples from volunteers on different diets were analysed. Further studies are required to discover a link between the presence of these biomarkers in urine and red meat consumption.


Assuntos
Desoxiguanosina/análogos & derivados , Guanina/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Animais , Cromatografia Líquida/métodos , Neoplasias Colorretais/urina , Estudos Cross-Over , Dano ao DNA , Desoxiguanosina/urina , Dieta , Dieta Vegetariana , Guanina/urina , Humanos , Limite de Detecção , Carne/análise
6.
Cell Rep ; 3(5): 1440-8, 2013 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-23643539

RESUMO

The identification of mutated metabolic enzymes in hereditary cancer syndromes has established a direct link between metabolic dysregulation and cancer. Mutations in the Krebs cycle enzyme, fumarate hydratase (FH), predispose affected individuals to leiomyomas, renal cysts, and cancers, though the respective pathogenic roles of mitochondrial and cytosolic FH isoforms remain undefined. On the basis of comprehensive metabolomic analyses, we demonstrate that FH1-deficient cells and tissues exhibit defects in the urea cycle/arginine metabolism. Remarkably, transgenic re-expression of cytosolic FH ameliorated both renal cyst development and urea cycle defects associated with renal-specific FH1 deletion in mice. Furthermore, acute arginine depletion significantly reduced the viability of FH1-deficient cells in comparison to controls. Our findings highlight the importance of extramitochondrial metabolic pathways in FH-associated oncogenesis and the urea cycle/arginine metabolism as a potential therapeutic target.


Assuntos
Fumarato Hidratase/metabolismo , Neoplasias Renais/enzimologia , Animais , Arginina/metabolismo , Ácido Argininossuccínico/metabolismo , Linhagem Celular , Ciclo do Ácido Cítrico , Fumarato Hidratase/deficiência , Fumarato Hidratase/genética , Fumaratos/metabolismo , Rim/enzimologia , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Metaboloma , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Mitocôndrias/metabolismo , Mutação , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Ureia/metabolismo
7.
Cancer Cell ; 23(3): 332-46, 2013 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-23518348

RESUMO

Understanding the mechanism underlying the regulation of the androgen receptor (AR), a central player in the development of castration-resistant prostate cancer (CRPC), holds promise for overcoming the challenge of treating CRPC. We demonstrate that the ubiquitin ligase Siah2 targets a select pool of NCOR1-bound, transcriptionally-inactive AR for ubiquitin-dependent degradation, thereby promoting expression of select AR target genes implicated in lipid metabolism, cell motility, and proliferation. Siah2 is required for prostate cancer cell growth under androgen-deprivation conditions in vitro and in vivo, and Siah2 inhibition promotes prostate cancer regression upon castration. Notably, Siah2 expression is markedly increased in human CRPCs. Collectively, we find that selective regulation of AR transcriptional activity by the ubiquitin ligase Siah2 is important for CRPC development.


Assuntos
Proteínas Nucleares/metabolismo , Correpressor 1 de Receptor Nuclear/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Transcrição Gênica , Ubiquitina-Proteína Ligases/metabolismo , Animais , Castração , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Metabolismo dos Lipídeos , Masculino , Camundongos , Proteínas Nucleares/genética , Interferência de RNA , RNA Interferente Pequeno , Transdução de Sinais , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/genética
8.
Cancer Cell ; 20(4): 524-37, 2011 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-22014577

RESUMO

The Krebs cycle enzyme fumarate hydratase (FH) is a human tumor suppressor whose inactivation is associated with the development of leiomyomata, renal cysts, and tumors. It has been proposed that activation of hypoxia inducible factor (HIF) by fumarate-mediated inhibition of HIF prolyl hydroxylases drives oncogenesis. Using a mouse model, we provide genetic evidence that Fh1-associated cyst formation is Hif independent, as is striking upregulation of antioxidant signaling pathways revealed by gene expression profiling. Mechanistic analysis revealed that fumarate modifies cysteine residues within the Kelch-like ECH-associated protein 1 (KEAP1), abrogating its ability to repress the Nuclear factor (erythroid-derived 2)-like 2 (Nrf2)-mediated antioxidant response pathway, suggesting a role for Nrf2 dysregulation in FH-associated cysts and tumors.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas do Citoesqueleto/metabolismo , Fumarato Hidratase/fisiologia , Fumaratos/metabolismo , Doenças Renais Císticas/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Succinatos/metabolismo , Animais , Antioxidantes/metabolismo , Hipóxia Celular , Fumarato Hidratase/genética , Fumarato Hidratase/metabolismo , Regulação Neoplásica da Expressão Gênica , Fator 1 Induzível por Hipóxia/genética , Fator 1 Induzível por Hipóxia/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch , Doenças Renais Císticas/genética , Camundongos , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Transdução de Sinais
9.
PLoS Genet ; 7(7): e1002145, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21765815

RESUMO

Forkhead-box protein P2 is a transcription factor that has been associated with intriguing aspects of cognitive function in humans, non-human mammals, and song-learning birds. Heterozygous mutations of the human FOXP2 gene cause a monogenic speech and language disorder. Reduced functional dosage of the mouse version (Foxp2) causes deficient cortico-striatal synaptic plasticity and impairs motor-skill learning. Moreover, the songbird orthologue appears critically important for vocal learning. Across diverse vertebrate species, this well-conserved transcription factor is highly expressed in the developing and adult central nervous system. Very little is known about the mechanisms regulated by Foxp2 during brain development. We used an integrated functional genomics strategy to robustly define Foxp2-dependent pathways, both direct and indirect targets, in the embryonic brain. Specifically, we performed genome-wide in vivo ChIP-chip screens for Foxp2-binding and thereby identified a set of 264 high-confidence neural targets under strict, empirically derived significance thresholds. The findings, coupled to expression profiling and in situ hybridization of brain tissue from wild-type and mutant mouse embryos, strongly highlighted gene networks linked to neurite development. We followed up our genomics data with functional experiments, showing that Foxp2 impacts on neurite outgrowth in primary neurons and in neuronal cell models. Our data indicate that Foxp2 modulates neuronal network formation, by directly and indirectly regulating mRNAs involved in the development and plasticity of neuronal connections.


Assuntos
Encéfalo/embriologia , Fatores de Transcrição Forkhead/genética , Redes Reguladoras de Genes , Neuritos/metabolismo , Proteínas Repressoras/genética , Animais , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Corpo Estriado/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Mutação , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Cultura Primária de Células , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
10.
Nat Immunol ; 12(3): 231-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21240265

RESUMO

Polymorphisms in the gene encoding the transcription factor IRF5 that lead to higher mRNA expression are associated with many autoimmune diseases. Here we show that IRF5 expression in macrophages was reversibly induced by inflammatory stimuli and contributed to the plasticity of macrophage polarization. High expression of IRF5 was characteristic of M1 macrophages, in which it directly activated transcription of the genes encoding interleukin 12 subunit p40 (IL-12p40), IL-12p35 and IL-23p19 and repressed the gene encoding IL-10. Consequently, those macrophages set up the environment for a potent T helper type 1 (T(H)1)-T(H)17 response. Global gene expression analysis demonstrated that exogenous IRF5 upregulated or downregulated expression of established phenotypic markers of M1 or M2 macrophages, respectively. Our data suggest a critical role for IRF5 in M1 macrophage polarization and define a previously unknown function for IRF5 as a transcriptional repressor.


Assuntos
Fatores Reguladores de Interferon/imunologia , Macrófagos/imunologia , Células Th1/imunologia , Células Th17/imunologia , Animais , Células Cultivadas , Citometria de Fluxo , Humanos , Immunoblotting , Fatores Reguladores de Interferon/genética , Camundongos , Camundongos Knockout , Análise em Microsséries
11.
Eur J Clin Invest ; 41(1): 52-8, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20840375

RESUMO

BACKGROUND: Electronic nose (E-nose) technology has been successfully used to diagnose a number of microbial infections. We have investigated the potential use of an E-nose for the diagnosis of ventilator-associated pneumonia (VAP) by detecting micro-organisms in bronchoalveolar lavage (BAL) fluid in a prospective comparative study of E-nose analysis and microbiology. MATERIALS AND METHODS: BAL samples were collected using a blind technique from 44 patients following a minimum of 72 h mechanical ventilation. Control samples were collected from six patients mechanically ventilated on the intensive care unit (ICU) immediately following elective surgery. Quantitative microbiological culture and E-nose headspace analysis of the BAL samples were undertaken. Multivariate analysis was applied to correlate E-nose response with microbiological growth. RESULTS: E-nose fingerprints correctly classified 77% of the BAL samples, with and without microbiological growth from patients not on antibiotics. Inclusion of patients on antibiotics resulted in 68% correct classification. Seventy per cent of isolates, cultured in the laboratory from the clinical samples, were accurately discriminated into four clinically significant groups. CONCLUSIONS: E-nose technology can accurately discriminate between different microbial species in BAL samples from ventilated patients on ICU at risk of developing VAP with accuracy comparable with accepted microbiological techniques.


Assuntos
Líquido da Lavagem Broncoalveolar/microbiologia , Lavagem Broncoalveolar/métodos , Pneumonia Associada à Ventilação Mecânica/microbiologia , Feminino , Humanos , Masculino , Pneumonia Associada à Ventilação Mecânica/diagnóstico , Estudos Prospectivos , Sensibilidade e Especificidade
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