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1.
Brain ; 147(1): 267-280, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38059801

RESUMO

The heterogenous aetiology of Parkinson's disease is increasingly recognized; both mitochondrial and lysosomal dysfunction have been implicated. Powerful, clinically applicable tools are required to enable mechanistic stratification for future precision medicine approaches. The aim of this study was to characterize bioenergetic dysfunction in Parkinson's disease by applying a multimodal approach, combining standardized clinical assessment with midbrain and putaminal 31-phosphorus magnetic resonance spectroscopy (31P-MRS) and deep phenotyping of mitochondrial and lysosomal function in peripheral tissue in patients with recent-onset Parkinson's disease and control subjects. Sixty participants (35 patients with Parkinson's disease and 25 healthy controls) underwent 31P-MRS for quantification of energy-rich metabolites [ATP, inorganic phosphate (Pi) and phosphocreatine] in putamen and midbrain. In parallel, skin biopsies were obtained from all research participants to establish fibroblast cell lines for subsequent quantification of total intracellular ATP and mitochondrial membrane potential (MMP) as well as mitochondrial and lysosomal morphology, using high content live cell imaging. Lower MMP correlated with higher intracellular ATP (r = -0.55, P = 0.0016), higher mitochondrial counts (r = -0.72, P < 0.0001) and higher lysosomal counts (r = -0.62, P = 0.0002) in Parkinson's disease patient-derived fibroblasts only, consistent with impaired mitophagy and mitochondrial uncoupling. 31P-MRS-derived posterior putaminal Pi/ATP ratio variance was considerably greater in Parkinson's disease than in healthy controls (F-tests, P = 0.0036). Furthermore, elevated 31P-MRS-derived putaminal, but not midbrain Pi/ATP ratios (indicative of impaired oxidative phosphorylation) correlated with both greater mitochondrial (r = 0.37, P = 0.0319) and lysosomal counts (r = 0.48, P = 0.0044) as well as lower MMP in both short (r = -0.52, P = 0.0016) and long (r = -0.47, P = 0.0052) mitochondria in Parkinson's disease. Higher 31P-MRS midbrain phosphocreatine correlated with greater risk of rapid disease progression (r = 0.47, P = 0.0384). Our data suggest that impaired oxidative phosphorylation in the striatal dopaminergic nerve terminals exceeds mitochondrial dysfunction in the midbrain of patients with early Parkinson's disease. Our data further support the hypothesis of a prominent link between impaired mitophagy and impaired striatal energy homeostasis as a key event in early Parkinson's disease.


Assuntos
Doença de Parkinson , Humanos , Fosfocreatina/metabolismo , Mitocôndrias/metabolismo , Corpo Estriado/metabolismo , Trifosfato de Adenosina/metabolismo
2.
Mov Disord ; 38(8): 1493-1502, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37246815

RESUMO

BACKGROUND: Rescue of mitochondrial function is a promising neuroprotective strategy for Parkinson's disease (PD). Ursodeoxycholic acid (UDCA) has shown considerable promise as a mitochondrial rescue agent across a range of preclinical in vitro and in vivo models of PD. OBJECTIVES: To investigate the safety and tolerability of high-dose UDCA in PD and determine midbrain target engagement. METHODS: The UP (UDCA in PD) study was a phase II, randomized, double-blind, placebo-controlled trial of UDCA (30 mg/kg daily, 2:1 randomization UDCA vs. placebo) in 30 participants with PD for 48 weeks. The primary outcome was safety and tolerability. Secondary outcomes included 31-phosphorus magnetic resonance spectroscopy (31 P-MRS) to explore target engagement of UDCA in PD midbrain and assessment of motor progression, applying both the Movement Disorder Society Unified Parkinson's Disease Rating Scale Part III (MDS-UPDRS-III) and objective, motion sensor-based quantification of gait impairment. RESULTS: UDCA was safe and well tolerated, and only mild transient gastrointestinal adverse events were more frequent in the UDCA treatment group. Midbrain 31 P-MRS demonstrated an increase in both Gibbs free energy and inorganic phosphate levels in the UDCA treatment group compared to placebo, reflecting improved ATP hydrolysis. Sensor-based gait analysis indicated a possible improvement of cadence (steps per minute) and other gait parameters in the UDCA group compared to placebo. In contrast, subjective assessment applying the MDS-UPDRS-III failed to detect a difference between treatment groups. CONCLUSIONS: High-dose UDCA is safe and well tolerated in early PD. Larger trials are needed to further evaluate the disease-modifying effect of UDCA in PD. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/complicações , Ácido Ursodesoxicólico/uso terapêutico , Método Duplo-Cego
4.
Sci Rep ; 12(1): 19835, 2022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36400790

RESUMO

Infantile fibrosarcoma is a rare childhood tumour that originates in the fibrous connective tissue of the long bones for which there is an urgent need to identify novel therapeutic targets. This study aims to clarify the role of the extracellular matrix component hyaluronan in the invasion of child fibroblasts and Infantile fibrosarcoma into the surrounding environment. Using nanoscale super-resolution STED (Stimulated emission depletion) microscopy followed by computational image analysis, we observed, for the first time, that invasive child fibroblasts showed increased nanoscale clustering of hyaluronan at the cell periphery, as compared to control cells. Hyaluronan was not observed within focal adhesions. Bioinformatic analyses further revealed that the increased nanoscale hyaluronan clustering was accompanied by increased gene expression of Hyaluronan synthase 2, reduced expression of Hyaluronidase 2 and CD44, and no change of Hyaluronan synthase 1 and Hyaluronidases 1, 3, 4 or 5. We further observed that the expression of the Hyaluronan synthase 1, 2 and 3, and the Hyaluronidase 3 and 5 genes was linked to reduced life expectancy of fibrosarcoma patients. The invasive front of infantile fibrosarcoma tumours further showed increased levels of hyaluronan, as compared to the tumour centre. Taken together, our findings are consistent with the possibility that while Hyaluronan synthase 2 increases the levels, the Hyaluronidases 3 and 5 reduce the weight of hyaluronan, resulting in the nanoscale clustering of hyaluronan at the leading edge of cells, cell invasion and the spread of Infantile fibrosarcoma.


Assuntos
Fibrossarcoma , Ácido Hialurônico , Humanos , Criança , Hialuronan Sintases/genética , Hialuronan Sintases/metabolismo , Ácido Hialurônico/metabolismo , Hialuronoglucosaminidase/genética , Hialuronoglucosaminidase/metabolismo , Fibrossarcoma/patologia , Fibroblastos/metabolismo , Análise por Conglomerados
5.
Sci Adv ; 8(35): eabo7958, 2022 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-36044575

RESUMO

Endothelial cell (EC) sensing of disturbed blood flow triggers atherosclerosis, a disease of arteries that causes heart attack and stroke, through poorly defined mechanisms. The Notch pathway plays a central role in blood vessel growth and homeostasis, but its potential role in sensing of disturbed flow has not been previously studied. Here, we show using porcine and murine arteries and cultured human coronary artery EC that disturbed flow activates the JAG1-NOTCH4 signaling pathway. Light-sheet imaging revealed enrichment of JAG1 and NOTCH4 in EC of atherosclerotic plaques, and EC-specific genetic deletion of Jag1 (Jag1ECKO) demonstrated that Jag1 promotes atherosclerosis at sites of disturbed flow. Mechanistically, single-cell RNA sequencing in Jag1ECKO mice demonstrated that Jag1 suppresses subsets of ECs that proliferate and migrate. We conclude that JAG1-NOTCH4 sensing of disturbed flow enhances atherosclerosis susceptibility by regulating EC heterogeneity and that therapeutic targeting of this pathway may treat atherosclerosis.


Assuntos
Aterosclerose , Proteína Jagged-1 , Placa Aterosclerótica , Receptor Notch4 , Animais , Aterosclerose/genética , Aterosclerose/metabolismo , Vasos Coronários/metabolismo , Células Endoteliais/metabolismo , Humanos , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismo , Camundongos , Placa Aterosclerótica/metabolismo , Receptor Notch4/genética , Receptor Notch4/metabolismo , Transdução de Sinais , Suínos
6.
Nat Commun ; 12(1): 7104, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34876579

RESUMO

Idiopathic pulmonary arterial hypertension (IPAH) is a rare but fatal disease diagnosed by right heart catheterisation and the exclusion of other forms of pulmonary arterial hypertension, producing a heterogeneous population with varied treatment response. Here we show unsupervised machine learning identification of three major patient subgroups that account for 92% of the cohort, each with unique whole blood transcriptomic and clinical feature signatures. These subgroups are associated with poor, moderate, and good prognosis. The poor prognosis subgroup is associated with upregulation of the ALAS2 and downregulation of several immunoglobulin genes, while the good prognosis subgroup is defined by upregulation of the bone morphogenetic protein signalling regulator NOG, and the C/C variant of HLA-DPA1/DPB1 (independently associated with survival). These findings independently validated provide evidence for the existence of 3 major subgroups (endophenotypes) within the IPAH classification, could improve risk stratification and provide molecular insights into the pathogenesis of IPAH.


Assuntos
Hipertensão Pulmonar Primária Familiar/genética , Hipertensão Pulmonar Primária Familiar/metabolismo , Perfilação da Expressão Gênica , Transcriptoma , 5-Aminolevulinato Sintetase , Regulação para Baixo , Cadeias beta de HLA-DP , Humanos , Hipertensão Arterial Pulmonar
7.
Int J Mol Sci ; 22(10)2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34069294

RESUMO

Systemic cobalt (Co) and chromium (Cr) concentrations may be elevated in patients with metal joint replacement prostheses. Several studies have highlighted the detrimental effects of this exposure on bone cells in vitro, but the underlying mechanisms remain unclear. In this study, we use whole-genome microarrays to comprehensively assess gene expression in primary human osteoblasts, osteoclast precursors and mature resorbing osteoclasts following exposure to clinically relevant circulating versus local periprosthetic tissue concentrations of Co2+ and Cr3+ ions and CoCr nanoparticles. We also describe the gene expression response in osteoblasts on routinely used prosthesis surfaces in the presence of metal exposure. Our results suggest that systemic levels of metal exposure have no effect on osteoblasts, and primarily inhibit osteoclast differentiation and function via altering the focal adhesion and extracellular matrix interaction pathways. In contrast, periprosthetic levels of metal exposure inhibit both osteoblast and osteoclast activity by altering HIF-1α signaling and endocytic/cytoskeletal genes respectively, as well as increasing inflammatory signaling with mechanistic implications for adverse reactions to metal debris. Furthermore, we identify gene clusters and KEGG pathways for which the expression correlates with increasing Co2+:Cr3+ concentrations, and has the potential to serve as early markers of metal toxicity. Finally, our study provides a molecular basis for the improved clinical outcomes for hydroxyapatite-coated prostheses that elicit a pro-survival osteogenic gene signature compared to grit-blasted and plasma-sprayed titanium-coated surfaces in the presence of metal exposure.


Assuntos
Cromo/administração & dosagem , Cobalto/administração & dosagem , Próteses Articulares Metal-Metal , Osteoblastos/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Artroplastia de Substituição , Reabsorção Óssea/induzido quimicamente , Células Cultivadas , Cromo/toxicidade , Cobalto/toxicidade , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Próteses Articulares Metal-Metal/efeitos adversos , Análise de Sequência com Séries de Oligonucleotídeos , Osteoblastos/fisiologia , Osteoclastos/fisiologia
8.
PLoS Comput Biol ; 17(5): e1008923, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33983944

RESUMO

The COVID-19 pandemic is shifting teaching to an online setting all over the world. The Galaxy framework facilitates the online learning process and makes it accessible by providing a library of high-quality community-curated training materials, enabling easy access to data and tools, and facilitates sharing achievements and progress between students and instructors. By combining Galaxy with robust communication channels, effective instruction can be designed inclusively, regardless of the students' environments.


Assuntos
COVID-19/epidemiologia , Instrução por Computador , Educação a Distância/organização & administração , COVID-19/virologia , Biologia Computacional , Humanos , Disseminação de Informação , Pandemias , SARS-CoV-2/isolamento & purificação
9.
Am J Respir Crit Care Med ; 202(4): 586-594, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32352834

RESUMO

Rationale: Idiopathic and heritable pulmonary arterial hypertension (PAH) are rare but comprise a genetically heterogeneous patient group. RNA sequencing linked to the underlying genetic architecture can be used to better understand the underlying pathology by identifying key signaling pathways and stratify patients more robustly according to clinical risk.Objectives: To use a three-stage design of RNA discovery, RNA validation and model construction, and model validation to define a set of PAH-associated RNAs and a single summarizing RNA model score. To define genes most likely to be involved in disease development, we performed Mendelian randomization (MR) analysis.Methods: RNA sequencing was performed on whole-blood samples from 359 patients with idiopathic, heritable, and drug-induced PAH and 72 age- and sex-matched healthy volunteers. The score was evaluated against disease severity markers including survival analysis using all-cause mortality from diagnosis. MR used known expression quantitative trait loci and summary statistics from a PAH genome-wide association study.Measurements and Main Results: We identified 507 genes with differential RNA expression in patients with PAH compared with control subjects. A model of 25 RNAs distinguished PAH with 87% accuracy (area under the curve 95% confidence interval: 0.791-0.945) in model validation. The RNA model score was associated with disease severity and long-term survival (P = 4.66 × 10-6) in PAH. MR detected an association between SMAD5 levels and PAH disease susceptibility (odds ratio, 0.317; 95% confidence interval, 0.129-0.776; P = 0.012).Conclusions: A whole-blood RNA signature of PAH, which includes RNAs relevant to disease pathogenesis, associates with disease severity and identifies patients with poor clinical outcomes. Genetic variants associated with lower SMAD5 expression may increase susceptibility to PAH.


Assuntos
Hipertensão Pulmonar Primária Familiar/sangue , Hipertensão Pulmonar Primária Familiar/genética , RNA/sangue , Adulto , Estudos de Coortes , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Análise da Randomização Mendeliana , Pessoa de Meia-Idade
10.
Glia ; 68(7): 1531-1545, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32212285

RESUMO

The contribution of microglia in neurological disorders is emerging as a leading disease driver rather than a consequence of pathology. RNAseT2-deficient leukoencephalopathy is a severe childhood white matter disorder affecting patients in their first year of life and mimicking a cytomegalovirus brain infection. The early onset and resemblance of the symptoms to a viral infection suggest an inflammatory and embryonic origin of the pathology. There are no treatments available for this disease as our understanding of the cellular drivers of the pathology are still unknown. In this study, using a zebrafish mutant for the orthologous rnaset2 gene, we have identified an inflammatory signature in early development and an antiviral immune response in mature adult brains. Using the optical transparency and the ex utero development of the zebrafish larvae we studied immune cell behavior during brain development and identified abnormal microglia as an early marker of pathology. Live imaging and electron microscopy identified that mutant microglia displayed an engorged morphology and were filled with undigested apoptotic cells and undigested substrate. Using microglia-specific depletion and rescue experiments, we identified microglia as drivers of this embryonic phenotype and potential key cellular player in the pathology of RNAseT2-deficient leukoencephalopathy. Our zebrafish model also presented with reduced survival and locomotor defects, therefore recapitulating many aspects of the human disease. Our study therefore placed our rnaset2 mutant at the forefront of leukodystrophy preclinical models and highlighted tissue-specific approaches as future therapeutic avenues.


Assuntos
Apoptose/fisiologia , Encéfalo/metabolismo , Leucoencefalopatias/patologia , Microglia/metabolismo , Animais , Leucoencefalopatias/metabolismo , Mutação/genética , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Fenótipo , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismo
12.
J Pathol ; 247(3): 381-391, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30426503

RESUMO

Skeletal metastasis occurs in around 75% of advanced breast cancers, with the disease incurable once cancer cells disseminate to bone, but there remains an unmet need for biomarkers to identify patients at high risk of bone recurrence. This study aimed to identify such a biomarker and to assess its utility in predicting response to adjuvant zoledronic acid (zoledronate). We used quantitative proteomics (stable isotope labelling by amino acids in cell culture-mass spectrometry; SILAC-MS) to compare protein expression in a bone-homing variant (BM1) of the human breast cancer cell line MDA-MB-231 with parental non-bone-homing cells to identify novel biomarkers for risk of subsequent bone metastasis in early breast cancer. SILAC-MS showed that dedicator of cytokinesis protein 4 (DOCK4) was upregulated in bone-homing BM1 cells, confirmed by western blotting. BM1 cells also had enhanced invasive ability compared with parental cells, which could be reduced by DOCK4-shRNA. In a training tissue microarray (TMA) comprising 345 patients with early breast cancer, immunohistochemistry followed by Cox regression revealed that high DOCK4 expression correlated with histological grade (p = 0.004) but not oestrogen receptor status (p = 0.19) or lymph node involvement (p = 0.15). A clinical validation TMA used tissue samples and the clinical database from the large AZURE adjuvant study (n = 689). Adjusted Cox regression analyses showed that high DOCK4 expression in the control arm (no zoledronate) was significantly prognostic for first recurrence in bone (HR 2.13, 95%CI 1.06-4.30, p = 0.034). No corresponding association was found in patients who received zoledronate (HR 0.812, 95%CI 0.176-3.76, p = 0.790), suggesting that treatment with zoledronate may counteract the higher risk for bone relapse from high DOCK4-expressing tumours. High DOCK4 expression was not associated with metastasis to non-skeletal sites when these were assessed collectively. In conclusion, high DOCK4 in early breast cancer is significantly associated with aggressive disease and with future bone metastasis and is a potentially useful biomarker for subsequent bone metastasis risk. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Ósseas/secundário , Neoplasias da Mama/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Conservadores da Densidade Óssea/uso terapêutico , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Quimioterapia Adjuvante , Feminino , Proteínas Ativadoras de GTPase/genética , Técnicas de Silenciamento de Genes/métodos , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Proteínas de Neoplasias/metabolismo , Prognóstico , Proteômica/métodos , Medição de Risco/métodos , Células Tumorais Cultivadas , Regulação para Cima , Adulto Jovem , Ácido Zoledrônico/uso terapêutico
13.
EMBO Mol Med ; 10(3)2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29437778

RESUMO

Genetically engineered mouse models of cancer can be used to filter genome-wide expression datasets generated from human tumours and to identify gene expression alterations that are functionally important to cancer development and progression. In this study, we have generated RNAseq data from tumours arising in two established mouse models of prostate cancer, PB-Cre/PtenloxP/loxP and p53loxP/loxPRbloxP/loxP, and integrated this with published human prostate cancer expression data to pinpoint cancer-associated gene expression changes that are conserved between the two species. To identify potential therapeutic targets, we then filtered this information for genes that are either known or predicted to be druggable. Using this approach, we revealed a functional role for the kinase MELK as a driver and potential therapeutic target in prostate cancer. We found that MELK expression was required for cell survival, affected the expression of genes associated with prostate cancer progression and was associated with biochemical recurrence.


Assuntos
Terapia de Alvo Molecular , Neoplasias da Próstata/terapia , Animais , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Carcinogênese/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Progressão da Doença , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genoma , Humanos , Masculino , Camundongos , Naftiridinas/farmacologia , Invasividade Neoplásica , Fenótipo , Fosforilação/efeitos dos fármacos , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Especificidade da Espécie , Fuso Acromático/efeitos dos fármacos , Fuso Acromático/metabolismo , Estatmina/metabolismo , Transcriptoma/genética
15.
Eur Urol ; 72(1): 22-31, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27815082

RESUMO

BACKGROUND: Localized prostate cancer is clinically heterogeneous, despite clinical risk groups that represent relative prostate cancer-specific mortality. We previously developed a 100-locus DNA classifier capable of substratifying patients at risk of biochemical relapse within clinical risk groups. OBJECTIVE: The 100-locus genomic classifier was refined to 31 functional loci and tested with standard clinical variables for the ability to predict biochemical recurrence (BCR) and metastasis. DESIGN, SETTING, AND PARTICIPANTS: Four retrospective cohorts of radical prostatectomy specimens from patients with localized disease were pooled, and an additional 102-patient cohort used to measure the 31-locus genomic classifier with the NanoString platform. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The genomic classifier scores were tested for their ability to predict BCR (n=563) and metastasis (n=154), and compared with clinical risk stratification schemes. RESULTS AND LIMITATIONS: The 31-locus genomic classifier performs similarly to the 100-locus classifier. It identifies patients with elevated BCR rates (hazard ratio=2.73, p<0.001) and patients that eventually develop metastasis (hazard ratio=7.79, p<0.001). Combining the genomic classifier with standard clinical variables outperforms clinical models. Finally, the 31-locus genomic classifier was implemented using a NanoString assay. The study is limited to retrospective cohorts. CONCLUSIONS: The 100-locus and 31-locus genomic classifiers reliably identify a cohort of men with localized disease who have an elevated risk of failure. The NanoString assay will be useful for selecting patients for treatment deescalation or escalation in prospective clinical trials based on clinico-genomic scores from pretreatment biopsies. PATIENT SUMMARY: It is challenging to determine whether tumors confined to the prostate are aggressive, leading to significant undertreatment and overtreatment. We validated a test based on prostate tumor DNA that improves estimations of relapse risk, and that can help guide treatment planning.


Assuntos
Biomarcadores Tumorais/genética , Perfilação da Expressão Gênica/métodos , Neoplasias da Próstata/genética , Transcriptoma , Tomada de Decisão Clínica , Variações do Número de Cópias de DNA , Técnicas de Apoio para a Decisão , Progressão da Doença , Dosagem de Genes , Humanos , Masculino , Gradação de Tumores , Metástase Neoplásica , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prostatectomia , Neoplasias da Próstata/classificação , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
16.
Nat Genet ; 48(4): 387-97, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26950096

RESUMO

Molecular characterization of genome-wide association study (GWAS) loci can uncover key genes and biological mechanisms underpinning complex traits and diseases. Here we present deep, high-throughput characterization of gene regulatory mechanisms underlying prostate cancer risk loci. Our methodology integrates data from 295 prostate cancer chromatin immunoprecipitation and sequencing experiments with genotype and gene expression data from 602 prostate tumor samples. The analysis identifies new gene regulatory mechanisms affected by risk locus SNPs, including widespread disruption of ternary androgen receptor (AR)-FOXA1 and AR-HOXB13 complexes and competitive binding mechanisms. We identify 57 expression quantitative trait loci at 35 risk loci, which we validate through analysis of allele-specific expression. We further validate predicted regulatory SNPs and target genes in prostate cancer cell line models. Finally, our integrated analysis can be accessed through an interactive visualization tool. This analysis elucidates how genome sequence variation affects disease predisposition via gene regulatory mechanisms and identifies relevant genes for downstream biomarker and drug development.


Assuntos
Neoplasias da Próstata/genética , Sequência de Bases , Sítios de Ligação , Fator de Ligação a CCCTC , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Neoplasias da Próstata/metabolismo , Ligação Proteica , Locos de Características Quantitativas , Proteínas Repressoras/metabolismo , Fatores de Risco , Análise de Sequência de DNA
17.
Eur Urol ; 70(2): 214-8, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26572708

RESUMO

UNLABELLED: The androgen receptor (AR) is the dominant growth factor in prostate cancer (PCa). Therefore, understanding how ARs regulate the human transcriptome is of paramount importance. The early effects of castration on human PCa have not previously been studied 27 patients medically castrated with degarelix 7 d before radical prostatectomy. We used mass spectrometry, immunohistochemistry, and gene expression array (validated by reverse transcription-polymerase chain reaction) to compare resected tumour with matched, controlled, untreated PCa tissue. All patients had levels of serum androgen, with reduced levels of intraprostatic androgen at prostatectomy. We observed differential expression of known androgen-regulated genes (TMPRSS2, KLK3, CAMKK2, FKBP5). We identified 749 genes downregulated and 908 genes upregulated following castration. AR regulation of α-methylacyl-CoA racemase expression and three other genes (FAM129A, RAB27A, and KIAA0101) was confirmed. Upregulation of oestrogen receptor 1 (ESR1) expression was observed in malignant epithelia and was associated with differential expression of ESR1-regulated genes and correlated with proliferation (Ki-67 expression). PATIENT SUMMARY: This first-in-man study defines the rapid gene expression changes taking place in prostate cancer (PCa) following castration. Expression levels of the genes that the androgen receptor regulates are predictive of treatment outcome. Upregulation of oestrogen receptor 1 is a mechanism by which PCa cells may survive despite castration.


Assuntos
Oligopeptídeos/administração & dosagem , Prostatectomia/métodos , Neoplasias da Próstata , Receptores Androgênicos/metabolismo , Receptor alfa de Estrogênio/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Antagonistas de Hormônios/administração & dosagem , Humanos , Imuno-Histoquímica , Masculino , Cuidados Pré-Operatórios , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Análise Espectral/métodos
18.
Genome Biol ; 16: 69, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25853800

RESUMO

BACKGROUND: The discovery of cytosine hydroxymethylation (5hmC) as a mechanism that potentially controls DNA methylation changes typical of neoplasia prompted us to investigate its behaviour in colon cancer. 5hmC is globally reduced in proliferating cells such as colon tumours and the gut crypt progenitors, from which tumours can arise. RESULTS: Here, we show that colorectal tumours and cancer cells express Ten-Eleven-Translocation (TET) transcripts at levels similar to normal tissues. Genome-wide analyses show that promoters marked by 5hmC in normal tissue, and those identified as TET2 targets in colorectal cancer cells, are resistant to methylation gain in cancer. In vitro studies of TET2 in cancer cells confirm that these promoters are resistant to methylation gain independently of sustained TET2 expression. We also find that a considerable number of the methylation gain-resistant promoters marked by 5hmC in normal colon overlap with those that are marked with poised bivalent histone modifications in embryonic stem cells. CONCLUSIONS: Together our results indicate that promoters that acquire 5hmC upon normal colon differentiation are innately resistant to neoplastic hypermethylation by mechanisms that do not require high levels of 5hmC in tumours. Our study highlights the potential of cytosine modifications as biomarkers of cancerous cell proliferation.


Assuntos
Neoplasias do Colo/genética , Citosina/análogos & derivados , Metilação de DNA/genética , Proteínas de Ligação a DNA/biossíntese , Proteínas Proto-Oncogênicas/biossíntese , 5-Metilcitosina/análogos & derivados , Proliferação de Células/genética , Neoplasias do Colo/patologia , Citosina/metabolismo , Proteínas de Ligação a DNA/genética , Dioxigenases , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Humanos , Proteínas Proto-Oncogênicas/genética
19.
Endocr Relat Cancer ; 22(2): 131-44, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25560400

RESUMO

Prostate cancer is the most common cancer in men, resulting in over 10 000 deaths/year in the UK. Sequencing and copy number analysis of primary tumours has revealed heterogeneity within tumours and an absence of recurrent founder mutations, consistent with non-genetic disease initiating events. Using methylation profiling in a series of multi-focal prostate tumours, we identify promoter methylation of the transcription factor HES5 as an early event in prostate tumourigenesis. We confirm that this epigenetic alteration occurs in 86-97% of cases in two independent prostate cancer cohorts (n=49 and n=39 tumour-normal pairs). Treatment of prostate cancer cells with the demethylating agent 5-aza-2'-deoxycytidine increased HES5 expression and downregulated its transcriptional target HES6, consistent with functional silencing of the HES5 gene in prostate cancer. Finally, we identify and test a transcriptional module involving the AR, ERG, HES1 and HES6 and propose a model for the impact of HES5 silencing on tumourigenesis as a starting point for future functional studies.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Carcinogênese/genética , Neoplasias da Próstata/genética , Proteínas Repressoras/genética , Linhagem Celular Tumoral , Metilação de DNA , Epigênese Genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Regiões Promotoras Genéticas , Neoplasias da Próstata/metabolismo , Transativadores/genética , Regulador Transcricional ERG
20.
Mol Oncol ; 9(1): 115-27, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25169931

RESUMO

Complex focal chromosomal rearrangements in cancer genomes, also called "firestorms", can be scored from DNA copy number data. The complex arm-wise aberration index (CAAI) is a score that captures DNA copy number alterations that appear as focal complex events in tumors, and has potential prognostic value in breast cancer. This study aimed to validate this DNA-based prognostic index in breast cancer and test for the first time its potential prognostic value in ovarian cancer. Copy number alteration (CNA) data from 1950 breast carcinomas (METABRIC cohort) and 508 high-grade serous ovarian carcinomas (TCGA dataset) were analyzed. Cases were classified as CAAI positive if at least one complex focal event was scored. Complex alterations were frequently localized on chromosome 8p (n = 159), 17q (n = 176) and 11q (n = 251). CAAI events on 11q were most frequent in estrogen receptor positive (ER+) cases and on 17q in estrogen receptor negative (ER-) cases. We found only a modest correlation between CAAI and the overall rate of genomic instability (GII) and number of breakpoints (r = 0.27 and r = 0.42, p < 0.001). Breast cancer specific survival (BCSS), overall survival (OS) and ovarian cancer progression free survival (PFS) were used as clinical end points in Cox proportional hazard model survival analyses. CAAI positive breast cancers (43%) had higher mortality: hazard ratio (HR) of 1.94 (95%CI, 1.62-2.32) for BCSS, and of 1.49 (95%CI, 1.30-1.71) for OS. Representations of the 70-gene and the 21-gene predictors were compared with CAAI in multivariable models and CAAI was independently significant with a Cox adjusted HR of 1.56 (95%CI, 1.23-1.99) for ER+ and 1.55 (95%CI, 1.11-2.18) for ER- disease. None of the expression-based predictors were prognostic in the ER- subset. We found that a model including CAAI and the two expression-based prognostic signatures outperformed a model including the 21-gene and 70-gene signatures but excluding CAAI. Inclusion of CAAI in the clinical prognostication tool PREDICT significantly improved its performance. CAAI positive ovarian cancers (52%) also had worse prognosis: HRs of 1.3 (95%CI, 1.1-1.7) for PFS and 1.3 (95%CI, 1.1-1.6) for OS. This study validates CAAI as an independent predictor of survival in both ER+ and ER- breast cancer and reveals a significant prognostic value for CAAI in high-grade serous ovarian cancer.


Assuntos
Neoplasias da Mama , Aberrações Cromossômicas , Cromossomos Humanos , DNA de Neoplasias , Bases de Dados Genéticas , Neoplasias Ovarianas , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Cromossomos Humanos/genética , Cromossomos Humanos/metabolismo , Estudos de Coortes , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Taxa de Sobrevida
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