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1.
Oncogene ; 37(8): 1005-1019, 2018 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-29084210

RESUMO

During normal tumor growth and in response to some therapies, tumor cells experience acute or chronic deprivation of nutrients and oxygen and induce tumor vascularization. While this occurs predominately through sprouting angiogenesis, tumor cells have also been shown to directly contribute to vessel formation through vascular mimicry (VM) and/or endothelial transdifferentiation. The extrinsic and intrinsic mechanisms underlying tumor cell adoption of endothelial phenotypes, however, are not well understood. Here we show that serum withdrawal induces mesenchymal breast cancer cells to undergo VM and that knockdown of the epithelial-to-mesenchymal transition (EMT) regulator, Zinc finger E-box binding homeobox 1 (ZEB1), or overexpression of the ZEB1-repressed microRNAs (miRNAs), miR-200c, miR-183, miR-96 and miR-182 inhibits this process. We find that secreted proteins Fibronectin 1 (FN1) and serine protease inhibitor (serpin) family E member 2 (SERPINE2) are essential for VM in this system. These secreted factors are upregulated in mesenchymal cells in response to serum withdrawal, and overexpression of VM-inhibiting miRNAs abrogates this upregulation. Intriguingly, the receptors for these secreted proteins, low-density lipoprotein receptor-related protein 1 (LRP1) and Integrin beta 1 (ITGB1), are also targets of the VM-inhibiting miRNAs, suggesting that autocrine signaling stimulating VM is regulated by ZEB1-repressed miRNA clusters. Together, these data provide mechanistic insight into the regulation of VM and suggest that miRNAs repressed during EMT, in addition to suppressing migratory and stem-like properties of tumor cells, also inhibit endothelial phenotypes of breast cancer cells adopted in response to a nutrient-deficient microenvironment.


Assuntos
Comunicação Autócrina , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/irrigação sanguínea , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neovascularização Patológica/patologia , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Prognóstico , Serpina E2/genética , Serpina E2/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética
2.
Meat Sci ; 94(4): 447-54, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23618740

RESUMO

Beef steaks (M. longissimus dorsi) were stored in modified atmosphere packs (MAP) (80% O2:20% CO2) with gas headspace to meat ratios of 2:1, 1:1 and 0.5:1 for 14 days at 4 °C. The pH, surface colour, texture and microbiology of beef steaks were unaffected (P>0.05) by varying the gas headspace to meat ratio. APLSR (ANOVA-partial least squares regression) and jack-knife uncertainty testing indicated that lipid oxidation (TBARS) was significantly positively correlated with days 10 (P<0.05) and 14 (P<0.001) of storage. Chemical and sensory detection of lipid oxidation in beef steaks were in agreement on day 14 of storage. The sensory quality and acceptability of beef steaks were similar in gas headspace to meat ratios of 2:1 or 1:1 and unacceptable in 0.5:1. Results indicate that pack size and gas volume can be reduced without negatively affecting fresh beef quality and shelf-life.


Assuntos
Atmosfera , Embalagem de Alimentos/métodos , Conservação de Alimentos/métodos , Peroxidação de Lipídeos , Carne/análise , Oxigênio , Paladar , Análise de Variância , Animais , Bovinos , Comportamento do Consumidor , Dieta , Humanos , Análise dos Mínimos Quadrados , Carne/normas
3.
Neuroscience ; 189: 215-22, 2011 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-21624435

RESUMO

The pathogenesis of neurodevelopmental disorders such as autism is believed to be influenced by interactions between genetic and environmental factors, and appropriate animal models are needed to assess the influence of such factors on relevant neurodevelopmental phenotypes. A set of inbred mouse strains (Atchley strains) including A12 (E+L0) and A22 (E-L0) were generated by age-specific restricted index selection from a baseline random-bred ICR mouse population obtained from Harlan Sprague-Dawley [Atchley et al. (1997) Genetics 146(2):629-640; Indianapolis, IN, USA). As compared with the A22 strain, A12 mice had significantly increased early (P0-P10) body weight gain with minimal changes in late (P28-P56) body weight gain. We found that these strains also differed in brain weight, brain volume, cell proliferation, and FGF-2 levels in certain brain regions. Specifically, brain weight and volume were significantly greater in A12 mice than that in A22 mice at P10 and P28. Quantitative analysis of bromodeoxyuridine (BrdU) labeling of proliferating cells showed that the number of BrdU-positive cells in the A12 strain were significantly greater in the frontal cortex and lesser in the dentate gyrus than that in the A22 strain at P28. Western blot revealed that fibroblast growth factors-2 (FGF-2), but not brain-derived neurotrophic factor (BDNF), expression was significantly increased in the frontal cortex of A12 strain at P28. Also, A12 mice exhibited decreased intra-strain social interaction and increased repetitive stereotyped behaviors at P28. Our study suggests that A12 mice may partially mimic the anatomic and behavioral traits of patients with neurodevelopmental disorders such as autism spectrum disorders, and therefore may yield insights into the developmental mechanisms involved in their pathogenesis.


Assuntos
Transtorno Autístico/patologia , Transtorno Autístico/psicologia , Encéfalo/patologia , Fatores Etários , Animais , Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Córtex Cerebral/metabolismo , Modelos Animais de Doenças , Fator 2 de Crescimento de Fibroblastos/metabolismo , Asseio Animal , Hipocampo/metabolismo , Relações Interpessoais , Camundongos , Camundongos Endogâmicos ICR , Tamanho do Órgão , Especificidade da Espécie , Comportamento Estereotipado
4.
Cancer Chemother Pharmacol ; 68(4): 863-70, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21286719

RESUMO

PURPOSE: Germline genetic variations may partly explain the clinical observation that normal tissue tolerance to radiochemotherapy varies by individual. Our objective was to evaluate the association between single-nucleotide polymorphisms (SNPs) in radiation/platinum pathways and serious treatment-related toxicity in subjects with esophageal adenocarcinoma who received cisplatin-based preoperative radiochemotherapy. METHODS: In a multicenter clinical trial (E1201), 81 eligible treatment-naïve subjects with resectable esophageal adenocarcinoma received cisplatin-based chemotherapy concurrent with radiotherapy, with planned subsequent surgical resection. Toxicity endpoints were defined as grade ≥3 radiation-related or myelosuppressive events probably or definitely related to therapy, occurring during or up to 6 weeks following the completion of radiochemotherapy. SNPs were analyzed in 60 subjects in pathways related to nucleotide/base excision- or double stranded break repair, or platinum influx, efflux, or detoxification. RESULTS: Grade ≥3 radiation-related toxicity (mostly dysphagia) and myelosuppression occurred in 18 and 33% of subjects, respectively. The variant alleles of the XRCC2 5' flanking SNP (detected in 28% of subjects) and of GST-Pi Ile-105-Val (detected in 65% of subjects) were each associated with higher odds of serious radiation-related toxicity compared to the major allele homozygote (47% vs. 9%, and 31% vs. 0%, respectively; P = 0.005). No SNP was associated with myelosuppression. CONCLUSIONS: This novel finding in a well-characterized cohort with robust endpoint data supports further investigation of XRCC2 and GST-Pi as potential predictors of radiation toxicity.


Assuntos
Adenocarcinoma/terapia , Cisplatino/administração & dosagem , Proteínas de Ligação a DNA/genética , Neoplasias Esofágicas/terapia , Glutationa S-Transferase pi/genética , Adenocarcinoma/genética , Adulto , Idoso , Antineoplásicos/administração & dosagem , Terapia Combinada , Neoplasias Esofágicas/genética , Feminino , Variação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Lesões por Radiação
5.
Pathologica ; 103(5): 271-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22393682

RESUMO

Synovial sarcoma (SS) is a soft tissue neoplasm with clearly defined histologic, immunohistochemical and molecular features that usually arises in the extremities of young adults. The occurrence of these tumors in the kidney is extremely rare and have been prevalently described in case reports. The objectives of this work were to evaluate the frequency of primary renal synovial sarcomas and the pathologic progression in recognition of this possibly under-diagnosed entity. A comprehensive review of the literature has also been performed with a focus on survival. We report the clinico-pathological features of an intrarenal SS occurring in a 67-year-old man. The tumour, measuring 4 cm in its greatest diameter, completely replaced the cortex and the medulla of the inferior region of the left kidney compressing the iliopsoas muscle. Radiological imaging was consistent with a renal cell carcinoma. Histologically, the tumour was composed of atypical monotonous vimentin+, CD99+, bcl-2+ spindle cells exhibiting a haphazard fascicular growth pattern and a high mitotic rate (3 to 5 mitoses per HPF). The diagnosis was supported by reverse transcription-polymerase chain reaction which demonstrated SYT-SSX2 gene fusion. The patient was alive with local recurrence of disease 24 months after surgery. Synovial sarcomas occurring in the kidney, in analogy to other sites, tend to have an aggressive biologic behaviour. Despite being extremely uncommon, with only 44 cases reported to date, they should be included in the differential diagnosis of benign and malignant spindle cell tumours of the kidney. This study also emphasizes the importance of a correct pathologic diagnosis for prognostic and therapeutic implications.


Assuntos
Neoplasias Renais/patologia , Sarcoma Sinovial/patologia , Idoso , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/diagnóstico por imagem , Diagnóstico Diferencial , Humanos , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Masculino , Mitose , Recidiva Local de Neoplasia , Fusão Oncogênica , Proteínas de Fusão Oncogênica/genética , Radiografia , Sarcoma Sinovial/genética , Sarcoma Sinovial/metabolismo , Resultado do Tratamento
6.
Plant Dis ; 95(2): 92-103, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30743428

RESUMO

Common bunt, caused by the seedborne and soilborne pathogens Tilletia caries and T. laevis, has re-emerged as a major disease in organic wheat. In conventional agriculture, common bunt is routinely managed with the use of synthetic chemical seed treatments. For this reason, common bunt is a relatively unimportant disease in conventional agriculture. However, since synthetic chemical inputs are prohibited in organic agriculture, common bunt is a major threat once more in organic wheat and seed production. The challenge today is to manage the disease without the use of chemical seed treatments. This review reports on the management of common bunt under organic farming systems, mainly through host resistance and organic seed treatments. We report the history of screening wheat germplasm for bunt resistance, the search for new sources of resistance, and identification and mapping of bunt resistance genes. Since the pathogen has a gene-for-gene relationship with the host, this review also includes a summary of work on pathogen race identification and virulence patterns of field isolates. Also included are studies on the physiological and molecular basis of host resistance. Alternative seed treatments are discussed, including physical seed treatments, and microbial-based and plant-based treatments acceptable in organic systems. The article concludes with a brief discussion on the current gaps in research on the management of common bunt in organic wheat.

7.
Am J Transplant ; 7(12): 2663-74, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17983390

RESUMO

Complex interactions between positive and negative cosignaling receptors ultimately determine the fate of the immune response. The recently identified coinhibitory receptor, B and T lymphocyte attenuator (BTLA), contributes to regulation of autoimmune and potentially alloimmune responses. We investigated the role of BTLA in a fully major histocompatibility complex-mismatched mouse islet transplant model. We report that anti-BTLA mAb (6F7) alone does not accelerate graft rejection. Rather, while CTLA4Ig alone improved allograft survival, the addition of anti-BTLA mAb to CTLA4Ig led to indefinite (>100 days) allograft survival. Immediately after treatment with anti-BTLA mAb and CTLA4Ig, islet allografts showed intact islets and insulin production despite a host cellular response, with local accumulation of Foxp3+ cells. We clearly demonstrate that combined therapy with anti-BTLA mAb and CTLA4Ig mice induced donor-specific tolerance, since mice accepted a second donor-specific islet graft without further treatment and rejected third party grafts. CTLA4Ig and anti-BTLA mAb limited the initial in vivo proliferation of CFSE-labeled allogeneic lymphocytes, and anti-BTLA mAb enhanced the proportion of PD-1 expressing T cells while depleting pathogenic BTLA+ lymphocytes. We conclude that targeting the BTLA pathway in conjunction with CTLA4Ig costimulatory blockade may be a useful strategy for promoting immunological tolerance in murine islet allografts.


Assuntos
Anticorpos Monoclonais/farmacologia , Imunoconjugados/farmacologia , Transplante das Ilhotas Pancreáticas/imunologia , Receptores Imunológicos/imunologia , Tolerância ao Transplante/efeitos dos fármacos , Abatacepte , Animais , Anticorpos Monoclonais/imunologia , Antígenos de Diferenciação/metabolismo , Glicemia/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Proliferação de Células/efeitos dos fármacos , Fatores de Transcrição Forkhead/metabolismo , Transplante das Ilhotas Pancreáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor de Morte Celular Programada 1 , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/patologia , Tolerância ao Transplante/imunologia , Transplante Homólogo , Regulação para Cima/efeitos dos fármacos
9.
Int J Obes (Lond) ; 30(8): 1211-6, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16446745

RESUMO

OBJECTIVE: To determine if hypocaloric diet, diet plus low-intensity exercise, and diet plus high-intensity exercise differentially influence subcutaneous abdominal and gluteal adipocyte size in obese individuals. DESIGN: Longitudinal intervention study of hypocaloric diet, diet plus low-intensity exercise, and diet plus high-intensity exercise (calorie deficit = 2800 kcal/week, 20 weeks). SUBJECTS: Forty-five obese, middle-aged women (BMI = 33.0+/-0.6 kg/m2, age = 58+/-1 years). MEASUREMENTS: Body composition testing and adipose tissue biopsies were conducted before and after the interventions. Subcutaneous abdominal and gluteal adipocyte size was determined. RESULTS: All three interventions reduced body weight, fat mass, percent fat, and waist and hip girths to a similar degree. Diet only did not change subcutaneous abdominal adipocyte size, whereas both diet plus exercise groups significantly reduced abdominal adipocyte size. Changes in abdominal adipocyte size in the diet plus exercise groups were significantly different from that of the diet group. Gluteal adipocyte size decreased similarly in all three groups. CONCLUSION: Addition of exercise training to dietary weight loss preferentially reduces subcutaneous abdominal adipocyte size in obese women. This may be of importance for the treatment of health complications associated with subcutaneous abdominal adiposity.


Assuntos
Adipócitos/citologia , Dieta Redutora , Exercício Físico/fisiologia , Obesidade/terapia , Redução de Peso/fisiologia , Composição Corporal/fisiologia , Tamanho Celular , Terapia Combinada , Feminino , Humanos , Pessoa de Meia-Idade , Consumo de Oxigênio , Gordura Subcutânea Abdominal/citologia
12.
Am J Hosp Palliat Care ; 20(3): 211-9, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12785043

RESUMO

Large numbers of persons in most types of healthcare settings have palliative care needs that have considerable impact on their quality of life. Therefore, InterRAI, a multinational consortium of researchers, clinicians, and regulators that uses assessment systems to improve the care of elderly and disabled persons, designed a standardized assessment tool, the Resident Assessment Instrument for Palliative Care (RAI-PC). The RAI-PC can be used for both the design of individual care plans and for case mix and outcomes research. Some elements of this instrument are taken from the resident assessment instrument (RAI) mandated for use in all nursing homes in the United States and widely used throughout the world. The RAI-PC can be used alone or in counjunction with the other assessment tools designed by the InterRAI collaboration: the RAI for homecare (RAI-HC), for acute care (RAI-AC), and for mental health care (RAI-MH). The objective of this study was to field test and carry out reliability studies on the RAI-PC. After appropriate approvals were obtained, the RAI-PC instrument was field tested on 151 persons in three countries in more than five types of settings. Data obtained from 144 of these individuals were analyzed for reliability. The reliability of the instrument was very good, with about 50 percent of the questions having kappa values of 0.8 or higher, and the average kappa value for each of the eight domains ranging from 0.76 to 0.95. The 54 men and 95 women had a mean age of 79 years. Thirty-four percent of individuals suffered pain daily. Eighty percent tired easily; 52 percent were breathless on exertion; and 19 to 53 percent had one or more other symptoms, including change in sleep pattern, dry mouth, nausea and vomiting, anorexia, breathlessness at rest, constipation, and diarrhea. The number of symptoms an individual reported increased as the estimated time until death declined. The "clinician friendly" RAI-PC can be used in multiple sites of care to facilitate both care planning and case mix and outcomes research.


Assuntos
Avaliação Geriátrica , Cuidados Paliativos , Planejamento de Assistência ao Paciente , Adulto , Idoso , República Tcheca , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Suécia , Estados Unidos
14.
Br J Biomed Sci ; 60(4): 204-9, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14725336

RESUMO

A total of 56 Neisseria meningitidis strains are analysed using multilocus sequence typing (MLST). Twenty-nine distinct sequence types (STs) were identified, eight of which were new. Four known hypervirulent clones--ST-11 (electrophoretic type [ET]-37) complex, ST-44 complex (lineage 3), ST-32 (ET-5) complex and ST-8 complex (cluster A4)--were identified by MLST in 35 disease-associated and four carrier strains. Two other clones (ST-22 complex and ST-269 complex) were identified in nine disease-associated and one carrier strain. The remaining strains were heterogeneous. Additional sequencing within the FumC gene further distinguished the ET-15 clone within the ST-11 (ET-37) clonal complex. This resolution of isolates into genetic clones by MLST enhances the more traditional techniques of serotyping and serosubtyping. The data obtained established that hyperendemic meningococcal disease in Ireland could be attributed to strains belonging to four major hypervirulent clones, all of which account for elevated levels of disease worldwide. The extra information provided by MLST will be used to study the population structure and epidemiology of N. meningitidis and will allow a comparison of Irish strains with those circulating globally.


Assuntos
Infecções Meningocócicas/microbiologia , Neisseria meningitidis/classificação , Técnicas de Tipagem Bacteriana/métodos , DNA Bacteriano/genética , Humanos , Dados de Sequência Molecular , Análise de Sequência de DNA/métodos , Sorotipagem
15.
J Neurosci Res ; 67(3): 372-8, 2002 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-11813242

RESUMO

Striatal neurons in symptomatic Huntington's disease (HD) transgenic mice are resistant to a variety of toxic insults, including quinolinic acid (QA), kainic acid and 3-nitropropionic acid. The basis for this resistance is currently unknown. To investigate the possibility that the immediate-early gene (IEG) response is defective in symptomatic HD mice leading to a lack of response to these compounds, we examined the expression of c-Fos and Krox 24 after administration of the indirect dopamine agonist methamphetamine, the dopamine D(2) receptor antagonist haloperidol and the neurotoxin QA in 5- and 10-week-old R6/2 transgenic HD and wild-type mice. Unlike wild-type and pre-symptomatic R6/2 transgenic HD mice, 10-week-old symptomatic HD mice were resistant to methamphetamine-induced gliosis and QA lesion. There was, however, no difference in the number or distribution of c-Fos-immunoreactive nuclei 2 hr after single injections of methamphetamine or haloperidol among 5- and 10-week-old wild-type mice and 5- and 10-week-old R6/2 HD mice. Similarly, despite their resistance to QA-induced lesioning and lower basal levels of krox-24 mRNA, the symptomatic R6/2 mice had equivalent increases in the amount of c-fos and krox-24 mRNA compared to wild-type and pre-symptomatic R6/2 HD mice as determined by in situ hybridization and densitometry 2 hr after QA administration. These data demonstrate that the c-Fos and Krox 24 IEG response to dopamine agonists, dopamine antagonists and neurotoxic insult is functional in symptomatic R6/2 HD mice. Resistance to toxic insult in R6/2 mice may be conferred by interactions of mutant huntingtin with proteins or transcriptional processes further along the toxic cascade.


Assuntos
Genes Precoces/efeitos dos fármacos , Haloperidol/farmacologia , Doença de Huntington/metabolismo , Proteínas Imediatamente Precoces , Metanfetamina/farmacologia , Proteínas do Tecido Nervoso , Ácido Quinolínico/farmacologia , Animais , Antidiscinéticos/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Corpo Caloso/efeitos dos fármacos , Corpo Caloso/metabolismo , Corpo Caloso/patologia , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Antagonistas de Dopamina/farmacologia , Fosfoproteína 32 Regulada por cAMP e Dopamina , Proteína 1 de Resposta de Crescimento Precoce , Expressão Gênica/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Doença de Huntington/genética , Doença de Huntington/patologia , Camundongos , Camundongos Transgênicos , Fosfoproteínas/metabolismo , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , RNA Mensageiro/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
16.
Br J Cancer ; 85(10): 1564-71, 2001 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-11720446

RESUMO

We have previously reported a strong correlation between poor prognosis in childhood neuroblastoma (NB) patients and high-level expression of the transmembrane efflux pump, Multidrug Resistance-associated Protein (MRP1), in NB tumour tissue. In this study, we inhibited the endogenous expression of MRP1 in 2 different NB tumour cell lines by stably transfecting an MRP1 antisense expression vector (MRP-AS). Compared with control cells, MRP-AS transfectant cells demonstrated a higher proportion of dead and morphologically apoptotic cells, spontaneous neuritogenesis, and, increased synaptophysin and neurofilament expression. Bcl-2 protein expression was markedly reduced in MRP-AS cells compared to controls. Conversely, we found that the same NB tumour cell line overexpressing the full-length MRP1 cDNA in sense orientation (MRP-S) demonstrated resistance to the neuritogenic effect of the differentiating agent, all-trans-retinoic acid. Taken together, the results suggest that the level of MRP1 expression in NB tumour cells may influence the capacity of NB cells for spontaneous regression in vivo through cell differentiation and death.


Assuntos
Apoptose , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/fisiologia , Neuroblastoma/patologia , Diferenciação Celular , Divisão Celular , Células Clonais , Relação Dose-Resposta a Droga , Regulação para Baixo , Expressão Gênica , Humanos , Marcação In Situ das Extremidades Cortadas , Microscopia de Fluorescência , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Neuroblastoma/metabolismo , Oligonucleotídeos Antissenso/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transfecção , Tretinoína/antagonistas & inibidores , Células Tumorais Cultivadas
17.
J Exp Med ; 194(10): 1461-71, 2001 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-11714753

RESUMO

The development of naive CD4+ T cells into a T helper (Th) 2 subset capable of producing interleukin (IL)-4, IL-5, and IL-13 involves a signal transducer and activator of transcription (Stat)6-dependent induction of GATA-3 expression, followed by Stat6-independent GATA-3 autoactivation. The friend of GATA (FOG)-1 protein regulates GATA transcription factor activity in several stages of hematopoietic development including erythrocyte and megakaryocyte differentiation, but whether FOG-1 regulates GATA-3 in T cells is uncertain. We show that FOG-1 can repress GATA-3-dependent activation of the IL-5 promoter in T cells. Also, FOG-1 overexpression during primary activation of naive T cells inhibited Th2 development in CD4+ T cells. FOG-1 fully repressed GATA-3-dependent Th2 development and GATA-3 autoactivation, but not Stat6-dependent induction of GATA-3. FOG-1 overexpression repressed development of Th2 cells from naive T cells, but did not reverse the phenotype of fully committed Th2 cells. Thus, FOG-1 may be one factor capable of regulating the Th2 development.


Assuntos
Linfócitos T CD4-Positivos/fisiologia , Proteínas de Transporte/fisiologia , Proteínas de Ligação a DNA/fisiologia , Proteínas Nucleares/fisiologia , Transativadores/fisiologia , Animais , Fator de Transcrição GATA3 , Interleucina-4/farmacologia , Camundongos , Camundongos Transgênicos , Fator de Transcrição STAT6 , Células Th2/fisiologia , Fatores de Transcrição , Transcrição Gênica
19.
J Immunol ; 167(2): 855-65, 2001 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-11441092

RESUMO

Analysis of the IFN-gamma promoter has primarily been conducted by transient expression of reporter constructs in transformed cells. However, the activity of cis elements may differ when expressed transiently compared with their activity within native chromatin. Furthermore, the transcription factors and signaling mechanisms in transformed cells may differ from those in normal T cells. To analyze IFN-gamma promoter regulation in normal T cells, we developed a novel retroviral bottom-strand reporter system to allow the chromatin integration of promoter regions in primary developing T cells. As controls, both the IL-2 and IL-4 promoters were inducible in this system, with the IL-4 reporter having Th2-specific activity. Strikingly, the IFN-gamma promoter exhibited constitutive activity in both Th1 and Th2 subsets, in contrast to the behavior of the endogenous IFN-gamma gene, which is inducible only in Th1 cells. In mapping this activity, we found that the AP-1/GM-CSF site in the distal promoter element is the most critical element for the constitutive activity. Transgenic reporter lines for the IFN-gamma promoter confirmed the constitutive behavior of the isolated IFN-gamma promoter. This constitutive activity was resistant to inhibition by cyclosporin A and was independent of Stat4 and p38 mitogen-activated protein kinase. These results suggest that IFN-gamma promoter regulation may require cis elements residing either downstream or >3.4 kb upstream of the transcriptional start site, involving repression of constitutive activity.


Assuntos
Genes Reporter/imunologia , Interferon gama/genética , Ativação Linfocitária/genética , Linfócitos T/imunologia , Linfócitos T/metabolismo , Animais , Linhagem Celular , Linhagem Celular Transformada , Ciclosporina/farmacologia , Proteínas de Ligação a DNA/fisiologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Interferon gama/biossíntese , Interferon gama/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Mutagênese Insercional , Regiões Promotoras Genéticas/efeitos dos fármacos , Regiões Promotoras Genéticas/imunologia , Fator de Transcrição STAT4 , Linfócitos T/efeitos dos fármacos , Transativadores/fisiologia , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/metabolismo , Células Tumorais Cultivadas
20.
Vet Dermatol ; 12(1): 49-58, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11301539

RESUMO

In canine and human atopic patients, the intracutaneous injection of offending allergens is followed by the development of both immediate and late-phase reactions. The present study was performed to expand on the characterization and dynamics of inflammatory cell subsets during IgE-mediated late-phase reactions in canine skin. Three normal dogs and three Dermatophagoides farinae-allergic dogs were selected for this experiment. All dogs were challenged intradermally with mite allergen, purified anticanine IgE antibodies (positive control) or phosphate-buffered saline (negative control). Skin biopsies were obtained before and 6, 12 and 24 h post-injection. Sections were stained with metachromatic and eosinophil-specific histological stains. Additionally, we used an immunohistochemical method with antibodies specific for canine leukocyte antigens. This study confirmed the occurrence of a late-phase reaction in atopic skin following allergen challenge, and in normal and atopic canine skin after intradermal injection of IgE-specific antibodies. Whereas early emigrating dermal cells were composed chiefly of neutrophil and activated eosinophil granulocytes, there was an influx of alpha beta T-lymphocytes and dermal dendritic cells in later stages of the late-phase reactions. Because IgE-mediated late-phase reactions resemble spontaneous atopic canine skin lesions, both at macroscopic and microscopic levels, we propose the use of similar challenges to study the anti-inflammatory effects of anti-allergic drugs in a pre-clinical setting.


Assuntos
Dermatite Atópica/veterinária , Doenças do Cão/imunologia , Imunoglobulina E/imunologia , Leucócitos , Alérgenos , Animais , Estudos de Casos e Controles , Dermatite Atópica/imunologia , Cães , Imuno-Histoquímica/veterinária , Ácaros
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