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1.
PLoS Biol ; 20(5): e3001660, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35594316

RESUMO

In polarized epithelial cells, receptor-ligand interactions can be restricted by different spatial distributions of the 2 interacting components, giving rise to an underappreciated layer of regulatory complexity. We explored whether such regulation occurs in the Drosophila wing disc, an epithelial tissue featuring the TGF-ß family member Decapentaplegic (Dpp) as a morphogen controlling growth and patterning. Dpp protein has been observed in an extracellular gradient within the columnar cell layer of the disc, but also uniformly in the disc lumen, leading to the question of how graded signaling is achieved in the face of 2 distinctly localized ligand pools. We find the Dpp Type II receptor Punt, but not the Type I receptor Tkv, is enriched at the basolateral membrane and depleted at the junctions and apical surface. Wit, a second Type II receptor, shows a markedly different behavior, with the protein detected on all membrane regions but enriched at the apical side. Mutational studies identified a short juxtamembrane sequence required for basolateral restriction of Punt in both wing discs and mammalian Madin-Darby canine kidney (MDCK) cells. This basolateral targeting (BLT) determinant can dominantly confer basolateral localization on an otherwise apical receptor. Rescue of punt mutants with transgenes altered in the targeting motif showed that flies expressing apicalized Punt due to the lack of a functional BLT displayed developmental defects, female sterility, and significant lethality. We also show that apicalized Punt does not produce an ectopic signal, indicating that the apical pool of Dpp is not a significant signaling source even when presented with Punt. Instead, we find that basolateral presentation of Punt is required for optimal signaling. Finally, we present evidence that the BLT acts through polarized sorting machinery that differs between types of epithelia. This suggests a code whereby each epithelial cell type may differentially traffic common receptors to enable distinctive responses to spatially localized pools of extracellular ligands.


Assuntos
Proteínas de Drosophila , Drosophila , Fator de Crescimento Transformador beta , Animais , Membrana Celular/metabolismo , Cães , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Feminino , Ligantes , Células Madin Darby de Rim Canino , Proteínas Serina-Treonina Quinases , Receptores de Superfície Celular/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo
2.
Ecol Lett ; 27(5): e14430, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38714364

RESUMO

Wintering birds serve as vital climate sentinels, yet they are often overlooked in studies of avian diversity change. Here, we provide a continental-scale characterization of change in multifaceted wintering avifauna and examine the effects of climate change on these dynamics. We reveal a strong functional reorganization of wintering bird communities marked by a north-south gradient in functional diversity change, along with a superimposed mild east-west gradient in trait composition change. Assemblages in the northern United States saw contractions of the functional space and increases in functional evenness and originality, while the southern United States saw smaller contractions of the functional space and stasis in evenness and originality. Shifts in functional diversity were underlined by significant reshuffling in trait composition, particularly pronounced in the western and northern United States. Finally, we find strong contributions of climate change to this functional reorganization, underscoring the importance of wintering birds in tracking climate change impacts on biodiversity.


Assuntos
Biodiversidade , Aves , Mudança Climática , Estações do Ano , Animais , Aves/fisiologia , Estados Unidos
3.
Mol Cell ; 59(6): 904-16, 2015 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-26344096

RESUMO

SPOP mutations and TMPRSS2-ERG rearrangements occur collectively in up to 65% of human prostate cancers. Although the two events are mutually exclusive, it is unclear whether they are functionally interrelated. Here, we demonstrate that SPOP, functioning as an E3 ubiquitin ligase substrate-binding protein, promotes ubiquitination and proteasome degradation of wild-type ERG by recognizing a degron motif at the N terminus of ERG. Prostate cancer-associated SPOP mutations abrogate the SPOP-mediated degradation function on the ERG oncoprotein. Conversely, the majority of TMPRSS2-ERG fusions encode N-terminal-truncated ERG proteins that are resistant to the SPOP-mediated degradation because of degron impairment. Our findings reveal degradation resistance as a previously uncharacterized mechanism that contributes to elevation of truncated ERG proteins in prostate cancer. They also suggest that overcoming ERG resistance to SPOP-mediated degradation represents a viable strategy for treatment of prostate cancers expressing either mutated SPOP or truncated ERG.


Assuntos
Proteínas Nucleares/fisiologia , Proteínas de Fusão Oncogênica/fisiologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Repressoras/fisiologia , Transativadores/fisiologia , Sequência de Aminoácidos , Proliferação de Células , Pontos de Quebra do Cromossomo , Células HEK293 , Humanos , Masculino , Fragmentos de Peptídeos/fisiologia , Neoplasias da Próstata/metabolismo , Ligação Proteica , Proteólise , Regulador Transcricional ERG , Ubiquitinação
4.
Eur J Vasc Endovasc Surg ; 63(3): 379-389, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35181225

RESUMO

OBJECTIVE: The aim was to enhance understanding of the role of platelet biomarkers in the pathogenesis of vascular events and risk stratifying patients with asymptomatic or symptomatic atherosclerotic carotid stenosis. DATA SOURCES: Systematic review conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. REVIEW METHODS: A systematic review collated data from 1975 to 2020 on ex vivo platelet activation and platelet function/reactivity in patients with atherosclerotic carotid stenosis. RESULTS: Forty-three studies met the inclusion criteria; the majority included patients on antiplatelet therapy. Five studies showed increased platelet biomarkers in patients with ≥ 30% asymptomatic carotid stenosis (ACS) vs. controls, with one neutral study. Preliminary data from one study suggested that quantification of "coated platelets" in combination with stenosis severity may aid risk stratification in patients with ≥ 50% - 99% ACS. Platelets were excessively activated in patients with ≥ 30% symptomatic carotid stenosis (SCS) vs. controls (≥ 11 positive studies and one neutral study). Antiplatelet-High on Treatment Platelet Reactivity (HTPR), previously called "antiplatelet resistance", was observed in 23% - 57% of patients on aspirin, with clopidogrel-HTPR in 25% - 100% of patients with ≥ 50% - 99% ACS. Aspirin-HTPR was noted in 9.5% - 64% and clopidogrel-HTPR in 0 - 83% of patients with ≥ 50% SCS. However, the data do not currently support the use of ex vivo platelet function/reactivity testing to tailor antiplatelet therapy outside of a research setting. Platelets are excessively activated (n = 5), with increased platelet counts (n = 3) in recently symptomatic vs. asymptomatic patients, including those without micro-emboli on transcranial Doppler (TCD) monitoring (n = 2). Most available studies (n = 7) showed that platelets become more reactive or activated following carotid endarterectomy or stenting, either as an acute phase response to intervention or peri-procedural treatment. CONCLUSION: Platelets are excessively activated in patients with carotid stenosis vs. controls, in recently symptomatic vs. asymptomatic patients, and may become activated/hyper-reactive following carotid interventions despite commonly prescribed antiplatelet regimens. Further prospective multicentre studies are required to determine whether models combining clinical, neurovascular imaging, and platelet biomarker data can facilitate optimised antiplatelet therapy in individual patients with carotid stenosis.


Assuntos
Estenose das Carótidas , Acidente Vascular Cerebral , Aspirina/uso terapêutico , Biomarcadores , Plaquetas , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/tratamento farmacológico , Humanos , Inibidores da Agregação Plaquetária/uso terapêutico , Acidente Vascular Cerebral/etiologia
5.
J Cell Mol Med ; 25(8): 4110-4123, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33704908

RESUMO

A crucial mutational mechanism in malignancy is structural variation, in which chromosomal rearrangements alter gene functions that drive cancer progression. Herein, the presence and pattern of structural variations were investigated in twelve prospectively acquired treatment-naïve pancreatic cancers specimens obtained via endoscopic ultrasound (EUS). In many patients, this diagnostic biopsy procedure and specimen is the only opportunity to identify somatic clinically relevant actionable alterations that may impact their care and outcome. Specialized mate pair sequencing (MPseq) provided genome-wide structural variance analysis (SVA) with a view to identifying prognostic markers and possible therapeutic targets. MPseq was successfully performed on all specimens, identifying highly rearranged genomes with complete SVA on all specimens with > 20% tumour content. SVA identified chimeric fusion proteins and potentially immunogenic readthrough transcripts, change of function truncations, gains and losses of key genes linked to tumour progression. Complex localized rearrangements, termed chromoanagenesis, with broad pattern heterogeneity were observed in 10 (83%) specimens, impacting multiple genes with diverse cellular functions that could influence theragnostic evaluation and responsiveness to immunotherapy regimens. This study indicates that genome-wide MPseq can be successfully performed on very limited clinically EUS obtained specimens for chromosomal rearrangement detection and potential theragnostic targets.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Ductal Pancreático/diagnóstico , Aberrações Cromossômicas , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Mutação , Neoplasias Pancreáticas/diagnóstico , Carcinoma Ductal Pancreático/diagnóstico por imagem , Carcinoma Ductal Pancreático/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/genética , Prognóstico , Transcriptoma
6.
Cancer Immunol Immunother ; 70(9): 2651-2656, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33599823

RESUMO

The dynamics of PD-L1 expression are poorly understood over the development of lung adenocarcinomas from pre-invasive lesions to fully invasive carcinomas. Given the importance of PD-L1 expression for the selection of patients to receive immunotherapy in the metastatic setting and possibly in the neoadjuvant setting, we sought to evaluate the agreement of PD-L1 expression in invasive and lepidic components of resected tumor specimens. We stained 86 adenocarcinomas for PD-L1 using the SP263 clone. We assessed the agreement of PD-L1 expression by tumor cells and immune cells between lepidic and invasive components. When both lepidic and invasive components were considered, PD-L1 positive immune cells and tumor cells were observed in 50 (58.1%) and 18 (20.9%) samples, respectively, using a ≥ 1% PD-L1 expression cutoff. Using a ≥ 1% cutoff for PD-L1 expression, positively stained tumor cells were observed in 11 (13%) lepidic and 15 (17%) invasive patterns, with agreement in 76 (88%) specimens and disagreement in 10 (12%) specimens (ĸ = 0.549). At ≥ 1% PD-L1 expression cutoff, PD-L1 positive immune cells were observed in 31 (35%) lepidic and 32 (37%) invasive patterns with an agreement of PD-L1 expression in 49 (57%) specimens and disagreement in 37 (43%) specimens (ĸ = 0.073). In our study of early stage adenocarcinomas of the lung, there was poor agreement in PD-L1 expression between paired invasive and lepidic components of tumors. Our data suggest that the non-invasive tumor components may not be as immunostimulatory as the invasive components, resulting in less adaptive expression of PD-L1.


Assuntos
Antígeno B7-H1/genética , Biomarcadores Tumorais , Expressão Gênica , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Antígeno B7-H1/metabolismo , Biópsia , Humanos , Imuno-Histoquímica , Invasividade Neoplásica , Estadiamento de Neoplasias , Reprodutibilidade dos Testes , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T/patologia
7.
Genomics ; 112(6): 5313-5323, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33144219

RESUMO

Intraoperative diagnosis is routinely performed on cytology touch preparations (TPs) from core needle biopsies (CNBs). Current interest promotes their utility as an important source of patient tissue for clinical genomic testing. Herein we present whole genome structural variant analysis (SVA) from mate-pair sequencing (MPseq) and whole exome sequencing (WES) mutation calling in DNA directly whole genome amplified (WGA) from TPs. Chromosomal copy changes and somatic DNA junction detection from MPseq of TPs were highly consistent with associated CNBs and bulk resected tissues in all cases. While increased frequency coverage noise from limitations of amplification of limited sample input was significant, this was effectively compensated by natural tumor enrichment during the TP process, which also enhanced variant detection and loss of heterozygosity evaluations from WES. This novel TP methodology enables expanded utility of frequently limited CNB for both clinical and research genomic testing.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Neoplasias/genética , Análise de Sequência de DNA , Alelos , Biópsia com Agulha de Grande Calibre , Técnicas Citológicas , Genômica/métodos , Humanos , Perda de Heterozigosidade , Neoplasias/patologia , Sequenciamento do Exoma
8.
Pancreatology ; 20(2): 229-238, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31831392

RESUMO

BACKGROUND & OBJECTIVES: Biomarkers are increasingly required to molecularly characterize pancreatic ductal adenocarcinoma (PDAC) subgroup populations, to determine who may benefit from immune based targeted therapy. We evaluated the feasibility of gene expression signature detection and the respective landscape of specific tumor infiltrating lymphocytes (TILs), cancer/testis (CT) antigens, and immune checkpoints for possible future personalized immunotherapy eligibility. METHODS: Dedicated digital mRNA oncologic immune profiling of 770 genes using a Nanostring nCounter® PanCancer Immune Profiling Panel was performed using archived endoscopic ultrasound fine needle biopsy (EUS FNB) PDAC specimens as a case series in a tertiary care setting. RESULTS: The spectrum of mRNA gene expression within the tumor specimens revealed that 44.8%, 10.0% and 50.7% of evaluated genes had a ≥ 2-fold increase, a ≤ 2-fold reduction or between <2 and >2 change of mRNA expression, when compared to normal controls. The corresponding landscape of TILs, CT antigens, and immune checkpoints highlighted several possibilities that could potentially be amenable to targeted personalized immunotherapy. This includes members of the Tumor Associated Macrophage family (CD68, CXCL5, and MARCO), members of the CT antigen family (PRAME, TTK and PBK) and the "second generation" checkpoints TIM3 and BTLA. CONCLUSIONS: Our study represents the ability to successfully perform digital mRNA expression profile analyses to immunophenotype PDAC EUS FNB specimens by evaluating the expression of >730 genes within the tumor immune microenvironment. This may facilitate the search for novel therapeutic targets, offering the opportunity to go beyond immune monotherapy, but perhaps to use combined immunomodulatory agents.


Assuntos
Carcinoma Ductal Pancreático/diagnóstico por imagem , Carcinoma Ductal Pancreático/terapia , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Imunoterapia/métodos , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/terapia , RNA Mensageiro/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias/química , Antígenos de Neoplasias/isolamento & purificação , Carcinoma Ductal Pancreático/imunologia , Feminino , Humanos , Linfócitos/química , Linfócitos/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/imunologia , Fenótipo , Medicina de Precisão , RNA Mensageiro/genética , RNA Neoplásico/genética , Microambiente Tumoral/genética
9.
Semin Immunol ; 28(5): 469-477, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27717536

RESUMO

Crosstalk between metabolic and immune pathways has recently become appreciated to be key to the regulation of host defence. The hypoxia-inducible factor (HIF) is a transcription factor which was initially described as a ubiquitous master regulator of the transcriptional response to hypoxia. In this role, HIF regulates genes promoting adaptation to hypoxia including a number which influence the cellular metabolic strategy of a cell. It has more recently been appreciated that the regulation of HIF is not restricted to oxygen-dependent pathways, and is now known to be mediated by a number of additional metabolic and immune cues including metabolites and cytokines respectively. Furthermore, our understanding of the functional role of HIF has expanded to it now being appreciated as a major regulator of host immunity. This places HIF in an ideal position to act as a regulatory hub which links metabolic activity with immunity. In this review we synthesise recent data which identifies HIF as both a target and effector for metabolic and immune processes. Developing our understanding of the role of HIF in this context will uncover new therapeutic targets for inflammatory and infectious disease.


Assuntos
Metabolismo Energético , Fator 1 Induzível por Hipóxia/metabolismo , Imunidade , Animais , Metabolismo Energético/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hipóxia/genética , Hipóxia/imunologia , Hipóxia/metabolismo , Imunomodulação , Inflamação/tratamento farmacológico , Inflamação/etiologia , Inflamação/metabolismo , Oxigenases de Função Mista/antagonistas & inibidores , Terapia de Alvo Molecular , Transdução de Sinais/efeitos dos fármacos
10.
Allergy ; 74(4): 753-766, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30394557

RESUMO

BACKGROUND: When an immune cell migrates from the bloodstream to a site of chronic inflammation, it experiences a profound decrease in microenvironmental oxygen levels leading to a state of cellular hypoxia. The hypoxia-inducible factor-1α (HIF-1α) promotes an adaptive transcriptional response to hypoxia and as such is a major regulator of immune cell survival and function. HIF hydroxylases are the family of oxygen-sensing enzymes primarily responsible for conferring oxygen dependence upon the HIF pathway. METHODS: Using a mouse model of allergic contact dermatitis (ACD), we tested the effects of treatment with the pharmacologic hydroxylase inhibitor DMOG, which mimics hypoxia, on disease development. RESULTS: Re-exposure of sensitized mice to 2,4-dinitrofluorobenzene (DNFB) elicited inflammation, edema, chemokine synthesis (including CXCL1 and CCL5) and the recruitment of neutrophils and eosinophils. Intraperitoneal or topical application of the pharmacologic hydroxylase inhibitors dymethyloxalylglycine (DMOG) or JNJ1935 attenuated this inflammatory response. Reduced inflammation was associated with diminished recruitment of neutrophils and eosinophils but not lymphocytes. Finally, hydroxylase inhibition reduced cytokine-induced chemokine production in cultured primary keratinocytes through attenuation of the JNK pathway. CONCLUSION: These data demonstrate that hydroxylase inhibition attenuates the recruitment of neutrophils to inflamed skin through reduction of chemokine production and increased neutrophilic apoptosis. Thus, pharmacologic inhibition of HIF hydroxylases may be an effective new therapeutic approach in allergic skin inflammation.


Assuntos
Aminoácidos Dicarboxílicos/uso terapêutico , Dermatite Alérgica de Contato/prevenção & controle , Oxigenases de Função Mista/antagonistas & inibidores , Aminoácidos Dicarboxílicos/farmacologia , Animais , Movimento Celular/efeitos dos fármacos , Citocinas/metabolismo , Eosinófilos/citologia , Humanos , Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia , Inflamação/tratamento farmacológico , Camundongos , Neutrófilos/citologia
11.
Eur J Vasc Endovasc Surg ; 57(2): 199-211, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30414802

RESUMO

OBJECTIVES: Carotid stenosis patients are at risk of vascular events despite antiplatelet therapy. Data on prescribed antiplatelet regimens have not been comprehensively collated from trials to guide optimal therapy in this population. METHODS: This review was conducted in line with the current Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Medline, Ovid, Embase, Web of Science, and Google Scholar from 1988 to 2018 were searched using the search terms "carotid stenosis", "asymptomatic", "symptomatic", "antiplatelet", and "anti-platelet" to identify randomised trials in patients with asymptomatic or symptomatic extracranial moderate-severe carotid stenosis on any form of antiplatelet therapy in which vascular events and pre specified composite outcome events were reported. RESULTS: Twenty-five studies were judged eligible for inclusion. Data from one randomised controlled trial showed no significant difference in benefit with aspirin versus placebo in asymptomatic carotid stenosis, but it is still reasonable to recommend aspirin (81-325 mg daily) for prevention of vascular events in these patients. Low to medium dose aspirin (81-325 mg daily) is superior to higher doses (>650 mg daily) at preventing recurrent vascular events in patients undergoing endarterectomy. Data from endovascular treatment (EVT) trials support peri-procedural treatment of asymptomatic and symptomatic patients with 81-325 mg of aspirin daily. The use of peri-procedural aspirin-clopidogrel in patients undergoing EVT is based on one pilot trial, but appears safe. Short-term aspirin-dipyridamole or aspirin-clopidogrel treatments are equally effective at reducing micro-embolic signals on transcranial Doppler ultrasound in patients with ≥50% symptomatic carotid stenosis. There is insufficient evidence to recommend routine aspirin-clopidogrel combination therapy to reduce the risk of recurrent clinical ischaemic events in patients with symptomatic moderate-severe carotid stenosis. CONCLUSIONS: This comprehensive review outlines an evidence based approach to antiplatelet therapy in carotid stenosis patients. Future trials should randomise such patients to receive different antiplatelet regimens to assess their efficacy and safety and to optimise peri-procedural and long-term preventive treatment in this patient cohort.


Assuntos
Estenose das Carótidas/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Acidente Vascular Cerebral/prevenção & controle , Aspirina/uso terapêutico , Doenças Assintomáticas/terapia , Estenose das Carótidas/cirurgia , Clopidogrel/uso terapêutico , Dipiridamol/uso terapêutico , Quimioterapia Combinada , Endarterectomia das Carótidas , Procedimentos Endovasculares , Humanos , Recidiva
12.
Genes Chromosomes Cancer ; 57(9): 459-470, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29726617

RESUMO

Copy number variation (CNV) is a common form of structural variation detected in human genomes, occurring as both constitutional and somatic events. Cytogenetic techniques like chromosomal microarray (CMA) are widely used in analyzing CNVs. However, CMA techniques cannot resolve the full nature of these structural variations (i.e. the orientation and location of associated breakpoint junctions) and must be combined with other cytogenetic techniques, such as karyotyping or FISH, to do so. This makes the development of a next-generation sequencing (NGS) approach capable of resolving both CNVs and breakpoint junctions desirable. Mate-pair sequencing (MPseq) is a NGS technology designed to find large structural rearrangements across the entire genome. Here we present an algorithm capable of performing copy number analysis from mate-pair sequencing data. The algorithm uses a step-wise procedure involving normalization, segmentation, and classification of the sequencing data. The segmentation technique combines both read depth and discordant mate-pair reads to increase the sensitivity and resolution of CNV calls. The method is particularly suited to MPseq, which is designed to detect breakpoint junctions at high resolution. This allows for the classification step to accurately calculate copy number levels at the relatively low read depth of MPseq. Here we compare results for a series of hematological cancer samples that were tested with CMA and MPseq. We demonstrate comparable sensitivity to the state-of-the-art CMA technology, with the benefit of improved breakpoint resolution. The algorithm provides a powerful analytical tool for the analysis of MPseq results in cancer.


Assuntos
Aberrações Cromossômicas , Variações do Número de Cópias de DNA/genética , Genoma Humano/genética , Sequenciamento de Nucleotídeos em Larga Escala , Algoritmos , Pontos de Quebra do Cromossomo , Rearranjo Gênico , Humanos , Análise Serial de Tecidos/métodos
13.
BMC Cancer ; 18(1): 738, 2018 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-30005627

RESUMO

BACKGROUND: HER2 positive (HER2+) breast cancers involve chromosomal structural alterations that act as oncogenic driver events. METHODS: We interrogated the genomic structure of 18 clinically-defined HER2+ breast tumors through integrated analysis of whole genome and transcriptome sequencing, coupled with clinical information. RESULTS: ERBB2 overexpression in 15 of these tumors was associated with ERBB2 amplification due to chromoanasynthesis with six of them containing single events and the other nine exhibiting multiple events. Two of the more complex cases had adverse clinical outcomes. Chromosomes 8 was commonly involved in the same chromoanasynthesis with 17. In ten cases where chromosome 8 was involved we observed NRG1 fusions (two cases), NRG1 amplification (one case), FGFR1 amplification and ADAM32 or ADAM5 fusions. ERBB3 over-expression was associated with NRG1 fusions and EGFR and ERBB3 expressions were anti-correlated. Of the remaining three cases, one had a small duplication fully encompassing ERBB2 and was accompanied with a pathogenic mutation. CONCLUSION: Chromoanasynthesis involving chromosome 17 can lead to ERBB2 amplifications in HER2+ breast cancer. However, additional large genomic alterations contribute to a high level of genomic complexity, generating the hypothesis that worse outcome could be associated with multiple chromoanasynthetic events.


Assuntos
Neoplasias da Mama/genética , Cromotripsia , Amplificação de Genes , Receptor ErbB-2/genética , Neoplasias da Mama/química , Neoplasias da Mama/patologia , Cromossomos Humanos Par 17 , Estudos de Coortes , Feminino , Humanos , Estadiamento de Neoplasias , Receptor ErbB-2/análise
14.
Pancreatology ; 18(1): 46-53, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29170050

RESUMO

OBJECTIVE: We used transcriptomic profiling and immunohistochemistry (IHC) to search for a functional imaging strategy to resolve common problems with morphological imaging of cystic neoplasms and benign cystic lesions of the pancreas. METHODS: Resected pancreatic cancer (n = 21) and normal pancreas were laser-capture micro-dissected, and transcripts were quantified by RNAseq. Functional imaging targets were validated at the protein level by IHC on a pancreatic adenocarcinoma tissue microarray and a newly created tissue microarray of resected intraductal papillary mucinous neoplasms (IPMNs) and IPMN-associated adenocarcinomas. RESULTS: Genes encoding proteins responsible for cellular import of pyruvate, export of lactate, and conversion of pyruvate to lactate were highly upregulated in pancreatic adenocarcinoma compared to normal pancreas. Strong expression of MCT4 and LDHA was observed by IHC in >90% of adenocarcinoma specimens. In IPMNs, the pyruvate-to-lactate signature was significantly elevated in high grade dysplasia (HGD) and IPMN-associated adenocarcinoma. Additionally, cores containing HGD and/or adenocarcinoma exhibited a higher number of peri-lesional stromal cells and a significant increase in peri-lesional stromal cell staining of LDHA and MCT4. Interestingly, the pyruvate-to-lactate signature was significantly upregulated in cores containing only low grade dysplasia (LGD) from patients with histologically confirmed IPMN-associated adenocarcinoma versus LGD cores from patients with non-invasive IPMNs. CONCLUSION: Our results suggest prospective studies with hyperpolarized [1-13C]-pyruvate magnetic resonance spectroscopic imaging are warranted. If these IHC results translate to functional imaging findings, a positive pyruvate-to-lactate imaging signature might be a risk factor for invasion that would warrant resection of IPMNs in the absence of other worrisome features.


Assuntos
Adenocarcinoma Mucinoso/química , Carcinoma Ductal Pancreático/química , Carcinoma Papilar/química , Ácido Láctico/química , Neoplasias Pancreáticas/química , Ácido Pirúvico/química , Adenocarcinoma Mucinoso/patologia , Biomarcadores Tumorais , Carcinoma Ductal Pancreático/patologia , Carcinoma Papilar/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Pâncreas/química , Pâncreas/patologia , Neoplasias Pancreáticas/patologia , Estudos Retrospectivos , Transcriptoma
16.
Ecol Lett ; 20(11): 1469-1478, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28980377

RESUMO

Negative distance dependence (NDisD), or reduced recruitment near adult conspecifics, is thought to explain the astounding diversity of tropical forests. While many studies show greater mortality at near vs. far distances from adults, these studies do not seek to track changes in the peak seedling curve over time, thus limiting our ability to link NDisD to coexistence. Using census data collected over 12 years from central Panama in conjunction with spatial mark-connection functions, we show evidence for NDisD for many species, and find that the peak seedling curve shifts away from conspecific adults over time. We find wide variation in the strength of NDisD, which was correlated with seed size and canopy position, but other life-history traits showed no relationship with variation in NDisD mortality. Our results document shifts in peak seedling densities over time, thus providing evidence for the hypothesized spacing mechanism necessary for diversity maintenance in tropical forests.


Assuntos
Biodiversidade , Florestas , Plântula/fisiologia , Árvores/fisiologia , Modelos Biológicos , Panamá , Densidade Demográfica , Dinâmica Populacional , Plântula/crescimento & desenvolvimento , Clima Tropical
17.
Mod Pathol ; 30(9): 1223-1233, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28643793

RESUMO

Sporadic lymphangioleiomyomatosis is a progressive pulmonary cystic disease resulting from the infiltration of smooth muscle-like lymphangioleiomyomatosis cells into the lung. The migratory/metastasizing properties of the lymphangioleiomyomatosis cell together with the presence of somatic mutations, primarily in the tuberous sclerosis complex gene (TSC2), lead many to consider this a low-grade malignancy. As malignant tumors characteristically accumulate somatic structural variations, which have not been well studied in sporadic lymphangioleiomyomatosis, we utilized mate pair sequencing to define structural variations within laser capture microdissected enriched lymphangioleiomyomatosis cell populations from five sporadic lymphangioleiomyomatosis patients. Lymphangioleiomyomatosis cells were confirmed in each tissue by hematoxylin eosin stain review and by HMB-45 immunohistochemistry in four cases. A mutation panel demonstrated characteristic TSC2 driver mutations in three cases. Genomic profiles demonstrated normal diploid coverage across all chromosomes, with no aneuploidy or detectable gains/losses of whole chromosomal arms typical of neoplastic diseases. However, somatic rearrangements and smaller deletions were validated in the two cases which lacked TSC2 driver mutations. Most significantly, one of these sporadic lymphangioleiomyomatosis cases contained two different size deletions encompassing the entire TSC1 locus. The detection of a homozygous deletion of TSC1 driving a predicted case of sporadic lymphangioleiomyomatosis, consistent with the common two-hit TSC2 mutation model, has never been reported for sporadic lymphangioleiomyomatosis. However, while no evidence of the hereditary tuberous sclerosis complex disease was reported for this patient, the potential for mosaicism and sub-clinical phenotype cannot be ruled out. Nevertheless, this study demonstrates that somatic structural rearrangements are present in lymphangioleiomyomatosis disease and provides a novel method of genomic characterization of sporadic lymphangioleiomyomatosis cells, aiding in defining cases with no detected mutations by conventional methodologies. These structural rearrangements could represent additional pathogenic mechanisms in sporadic lymphangioleiomyomatosis disease, potentially affecting response to therapy and adding to the complex genetic story of this rare disease.


Assuntos
Biomarcadores Tumorais/genética , Rearranjo Gênico , Neoplasias Pulmonares/genética , Linfangioleiomiomatose/genética , Proteínas Supressoras de Tumor/genética , Biomarcadores Tumorais/análise , Análise Mutacional de DNA , Deleção de Genes , Predisposição Genética para Doença , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/química , Linfangioleiomiomatose/metabolismo , Antígenos Específicos de Melanoma/análise , Mutação , Fenótipo , Proteína 1 do Complexo Esclerose Tuberosa , Proteína 2 do Complexo Esclerose Tuberosa , Antígeno gp100 de Melanoma
18.
Ecol Appl ; 27(6): 1731-1745, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28434188

RESUMO

There is increasing recognition that community assembly theory can offer valuable insights for ecological restoration. We studied community assembly processes following tropical forest restoration efforts, using dung beetles (Scarabaeinae) as a focal taxon to investigate taxonomic and functional patterns of biodiversity recovery. We evaluated the relative importance of the local environment (i.e., canopy cover, understory cover, tree basal area, and soil texture), landscape context (i.e., habitat patch proximity and availability and percentage of surrounding area classified as natural forest or Eucalyptus spp. plantation), and space (i.e., spatial proximity of the study areas to estimate dispersal limitation or unmeasured spatially structured processes) on dung beetle species and functional trait composition across a gradient of 15 restoration sites in Brazilian Atlantic Forest. We also assessed which factors were the primary determinants in the establishment of individual dung beetle functional groups, classified according to size, food relocation habit, diet, and period of flight activity. Both species and functional trait composition were most strongly influenced by the local environment, indicating that assembly was predominantly driven by niche-based processes. Most of the variation explained by space was co-explained by local environment and landscape context, ruling out a strong influence of dispersal limitation and random colonization on assembly following restoration. In addition, nearly all of the variance explained by landscape context was co-explained by local environment, suggesting that arrival and establishment at a site depends on both local and landscape-scale environmental factors. Despite strong evidence for niche-based assembly, a large amount of variation remained unexplained in all models, suggesting that stochastic processes and/or unmeasured environmental variables also play an important role. The relative importance of local environment, landscape context, and space changed considerably when analyzing the assembly mechanisms of each functional group separately. Therefore, to recover distinct functional traits in restoration sites, it may be necessary to manipulate different components of the local environment and surrounding landscape. Overall, this study shows that assembly rules can help to better understand recovery processes, enabling improvement of future restoration efforts.


Assuntos
Distribuição Animal , Besouros/fisiologia , Meio Ambiente , Florestas , Animais , Brasil , Densidade Demográfica , Estações do Ano , Processos Estocásticos , Árvores/fisiologia , Clima Tropical
20.
Mod Pathol ; 29(2): 143-56, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26612463

RESUMO

Patients with clinically insignificant prostate cancer remain a major over-treated population. PTEN loss is one of the most recurrent alterations in prostate cancer associated with an aggressive phenotype, however, the occurrence of PTEN loss in insignificant prostate cancer has not been reported and its role in the separation of insignificant from significant prostate cancer is unclear. An integrated analysis of PTEN loss was, therefore, performed for structural variations, point mutations and protein expression in clinically insignificant (48 cases) and significant (76 cases) prostate cancers treated by radical prostatectomy. Whole-genome mate pair sequencing was performed on tumor cells isolated by laser capture microdissection to characterize PTEN structural alterations. Fluorescence in situ hybridization probes were constructed from the sequencing data to detect the spectrum of these PTEN alterations. PTEN loss by mate pair sequencing and fluorescence in situ hybridization occurred in 2% of insignificant, 13% of large volume Gleason score 6, and 46% of Gleason score 7 and higher cancers. In Gleason score 7 cancers with PTEN loss, PTEN alterations were detected in both Gleason pattern 3 and 4 in 57% of cases by mate pair sequencing, 75% by in situ hybridization and 86% by immunohistochemistry. PTEN loss by sequencing was strongly associated with TMPRSS2-ERG fusion, biochemical recurrence, PTEN loss by in situ hybridization and protein loss by immunohistochemistry. The complex nature of PTEN rearrangements was unveiled by sequencing, detailing the heterogeneous events leading to homozygous loss of PTEN. PTEN point mutation was present in 5% of clinically significant tumors and not in insignificant cancer or high-grade prostatic intraepithelial neoplasia. PTEN loss is infrequent in clinically insignificant prostate cancer, and is associated with higher grade tumors. Detection of PTEN loss in Gleason score 6 cancer in a needle biopsy specimen indicates a higher likelihood of clinically significant prostate cancer.


Assuntos
Biomarcadores Tumorais/genética , Instabilidade Genômica , PTEN Fosfo-Hidrolase/genética , Neoplasias da Próstata/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Biópsia por Agulha , Análise Mutacional de DNA , Fusão Gênica , Rearranjo Gênico , Predisposição Genética para Doença , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Proteínas de Fusão Oncogênica/genética , PTEN Fosfo-Hidrolase/análise , Fenótipo , Mutação Puntual , Prostatectomia , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Análise de Sobrevida , Resultado do Tratamento
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