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1.
J Antimicrob Chemother ; 73(8): 2047-2053, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29684150

RESUMO

Objectives: Aspergillus fumigatus is the most prevalent filamentous fungus in the respiratory tract of patients with cystic fibrosis (CF). The aim of this prospective multicentre study was to investigate the prevalence of azole-resistant A. fumigatus (ARAF) in respiratory secretions from CF patients across Germany and to characterize ARAF isolates by phenotypic and molecular methods. Methods: Twelve tertiary care centres from Germany participated in the study. In total, 2888 A. fumigatus isolates from 961 CF patients were screened for ARAF by using azole-containing agar plates. Antifungal susceptibility testing of isolates was performed by broth microdilution according to EUCAST guidelines. Analysis of mutations mediating resistance was performed using PCR and sequencing of the cyp51A gene. Furthermore, genotyping by microsatellite PCR was performed. Results: Of a total of 2888 A. fumigatus isolates, 101 isolates from 51 CF patients were found to be azole resistant (prevalence per patient 5.3%). The Essen centre had the highest prevalence (9.1%) followed by Munich (7.8%), Münster (6.0%) and Hannover (5.2%). Most ARAF isolates (n = 89) carried the TR34/L98H mutation followed by eight G54E/R, one TR46/Y121F/T289A and one F219S mutation. In two isolates no mutation was found. Genotyping results showed no major clustering. Forty-five percent of CF patients with ARAF had previously received azole therapy. Conclusions: This is the first multicentre study analysing the prevalence of ARAF isolates in German CF patients. Because of a resistance rate of up to 9%, susceptibility testing of A. fumigatus isolates from CF patients receiving antifungal treatment should be part of standard diagnostic work-up.


Assuntos
Antifúngicos/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Azóis/farmacologia , Fibrose Cística/microbiologia , Farmacorresistência Fúngica , Adulto , Aspergillus fumigatus/genética , Aspergillus fumigatus/isolamento & purificação , Sistema Enzimático do Citocromo P-450/genética , Análise Mutacional de DNA , Feminino , Proteínas Fúngicas/genética , Genótipo , Alemanha , Humanos , Masculino , Testes de Sensibilidade Microbiana , Repetições de Microssatélites , Técnicas de Tipagem Micológica , Prevalência , Estudos Prospectivos
2.
Pathologe ; 34(6): 534-9, 2013 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-24154754

RESUMO

The majority of mycoses which lead to mycotic tumors in patients without any predisposing underlying disease are either caused by Cryptococcus gattii and C. neoformans or by dematiaceous fungi which include Cladophialophora bantiana, Ramichloridium mackenziei, Exophiala and Fonsecaea species. The detection of hyphae in granuloma in the brain should lead to screening for pigmented fungi, which are recognized best in hematoxylin eosin (HE) or sometimes also in periodic acid-Schiff (PAS) stained sections. In patients who survive a near drowning accident and those who develop brain abscesses, scedosporiosis should always be considered as a possible infection.


Assuntos
Encefalopatias/patologia , Infecções Fúngicas do Sistema Nervoso Central/patologia , Imunocompetência , Basidiomycota/classificação , Basidiomycota/ultraestrutura , Encéfalo/microbiologia , Encéfalo/patologia , Encefalopatias/imunologia , Encefalopatias/microbiologia , Infecções Fúngicas do Sistema Nervoso Central/imunologia , Infecções Fúngicas do Sistema Nervoso Central/microbiologia , Feoifomicose Cerebral/imunologia , Feoifomicose Cerebral/microbiologia , Feoifomicose Cerebral/patologia , Cryptococcus gattii/classificação , Cryptococcus gattii/ultraestrutura , Diagnóstico Diferencial , Fungos/classificação , Fungos/isolamento & purificação , Meningite Criptocócica/imunologia , Meningite Criptocócica/microbiologia , Meningite Criptocócica/patologia , Técnicas de Tipagem Micológica , Scedosporium/classificação , Scedosporium/ultraestrutura
3.
Mycoses ; 55(3): e124-37, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22233267

RESUMO

Descriptive values were determined for eight antifungal agents within the course of a multi-centre study encompassing 1062 German and Austrian clinical yeast isolates. Candida albicans (54%) was the predominant species isolated followed by Candida glabrata (22%), Candida parapsilosis (6%), Candida tropicalis (5.7%), Candida krusei (4.3%), as well as eleven further candidal and four non-Candida yeast species. While 519 (48.9%) isolates were tested susceptible to all antifungals tested, no isolate was found to exhibit complete cross resistance. For C. albicans, the proportions of susceptible isolates were 93.2% (amphotericin B), 95.6% (flucytosine), 84.3% (fluconazole), 83.8% (posaconazole), 91.8% (voriconazole), 96.5% (anidulafungin), 96.2% (caspofungin) and 97.6% (micafungin). Patterns of complete parallel resistances were observed within azoles (8.8%) and echinocandins (1.7%). While a decreased susceptibility was found infrequently for echinocandins and flucytosine, it was more common for azoles with highest proportions for isolates of C. glabrata (fluconazole, 40.6%; posaconazole, 37.2%), Candida guilliermondii (fluconazole and posaconazole, each 25.0%), C. krusei (posaconazole, 28.3%; voriconazole, 60%), C. parapsilosis (fluconazole, 70.3%) and C. tropicalis (fluconazole, 62.3%). The descriptive values obtained in this study represent a valid basis for the comparison of recent and future epidemiological surveys to analyse the susceptibility of yeast isolates towards major antifungal substances.


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Azóis/farmacologia , Candida/efeitos dos fármacos , Candidíase/microbiologia , Equinocandinas/farmacologia , Flucitosina/farmacologia , Candida/classificação , Candida/isolamento & purificação , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana
4.
Hum Mol Genet ; 18(12): 2127-39, 2009 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-19304783

RESUMO

Three neurodegenerative diseases affecting upper and/or lower motor neurons have been associated with loss of ALS2/Alsin function: juvenile amyotrophic lateral sclerosis, primary lateral sclerosis and infantile-onset ascending hereditary spastic paralysis. The distinct neuronal vulnerability and the role of glia in these diseases remains, however, unclear. We here demonstrate that alsin-depleted spinal motor neurons can be rescued from defective survival and axon growth by co-cultured astrocytes. The astrocytic rescue is mediated by a soluble protective factor rather than by cellular contact. Cortical neurons are intrinsically as vulnerable to alsin depletion as spinal motor neurons but cannot be rescued by co-cultured astrocytes. To our knowledge, these data provide the first example of non-cell-autonomous glial effects in a recessive form of motor neuron disease and a potential rationale for the higher vulnerability of upper versus lower motor neurons in ALS2/Alsin-linked disorders.


Assuntos
Astrócitos/metabolismo , Córtex Cerebral/citologia , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Doença dos Neurônios Motores/metabolismo , Neurônios Motores/metabolismo , Coluna Vertebral/citologia , Animais , Linhagem Celular , Células Cultivadas , Córtex Cerebral/metabolismo , Córtex Cerebral/fisiopatologia , Modelos Animais de Doenças , Fatores de Troca do Nucleotídeo Guanina/genética , Humanos , Camundongos , Camundongos Knockout , Doença dos Neurônios Motores/genética , Doença dos Neurônios Motores/fisiopatologia , Coluna Vertebral/metabolismo , Coluna Vertebral/fisiopatologia
5.
Nat Med ; 5(2): 231-5, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9930874

RESUMO

The beta2 integrin LFA-1 (lymphocyte function associated antigen; CD11a/CD18) is the common ligand for the intercellular adhesion molecules (ICAMs). Integrins support cell function by providing co-stimulatory second signals that are a precondition for full cell activation first described for ICAM-1-binding to LFA-1 in lymphocytes. Integrins can also serve to activate functions associated with distinct subunits of other integrins. In addition to LFA-1, neutrophils express the beta2 integrin Mac-1 (CD11b/CD18; CR3) that apparently contains multiple sites that bind invading microbes directly or through surface-fixed C3, resulting in activation of the phagocyte function. Expression of the LFA-1 counter-receptor ICAM-1 on endothelial cells occurs only at the site of inflammation. Therefore, in neutrophils, ICAM-1 ligand binding could, as with lymphocytes, also play a part as a co-stimulatory signal to induce full phagocytotic function. We show that in neutrophils, the LFA-1 ligand interaction is the stimulatory signal to express full phagocytotic activation. This is best demonstrated by the rapid association of Streptococcus pyogenes with neutrophils, followed by ingestion, strong oxidative-burst induction and enhanced killing of these bacteria, which are well-known for their resistance to human neutrophil defense. These findings may contribute to the development of therapeutic strategies targeting the modulation of ICAM-1-leukocyte interaction.


Assuntos
Molécula 1 de Adesão Intercelular/metabolismo , Antígeno-1 Associado à Função Linfocitária/metabolismo , Neutrófilos/imunologia , Fagocitose , Anticorpos Monoclonais/imunologia , Separação Celular , Células Cultivadas , Citotoxicidade Imunológica , Citometria de Fluxo , Humanos , Modelos Imunológicos , Explosão Respiratória , Streptococcus pyogenes/imunologia
6.
Nat Med ; 3(4): 429-36, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9095177

RESUMO

Motor neuron diseases such as amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy cause progressive paralysis, often leading to premature death. Neurotrophic factors have been suggested as therapeutic agents for motor neuron diseases, but their clinical use as injected recombinant protein was limited by toxicity and/or poor bioavailability. We demonstrate here that adenovirus-mediated gene transfer of neurotrophin-3 (NT-3) can produce substantial therapeutic effects in the mouse mutant pmn (progressive motor neuronopathy). After intramuscular injection of the NT-3 adenoviral vector, pmn mice showed a 50% increase in life span, reduced loss of motor axons and improved neuromuscular function as assessed by electromyography. These results were further improved by coinjecting an adenoviral vector coding for ciliary neurotrophic factor. Therefore, adenovirus-mediated gene transfer of neurotrophic factors offers new prospects for the treatment of motor neuron diseases.


Assuntos
Terapia Genética/métodos , Doença dos Neurônios Motores/terapia , Fatores de Crescimento Neural/uso terapêutico , Proteínas do Tecido Nervoso/uso terapêutico , Adenoviridae/genética , Animais , Animais Recém-Nascidos , Fator Neurotrófico Ciliar , Eletromiografia , Vetores Genéticos , Injeções Intramusculares , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Mutantes , Doença dos Neurônios Motores/mortalidade , Músculos/inervação , Degeneração Neural/efeitos dos fármacos , Fatores de Crescimento Neural/genética , Proteínas do Tecido Nervoso/genética , Neurotrofina 3 , Nervo Frênico/patologia , Análise de Sobrevida
7.
Infection ; 38(3): 205-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20333433

RESUMO

BACKGROUND: Data on time-dependency of external ventricular drainage (EVD)- and lumbar drainage (LD)-associated meningoventriculitis (MV) are scarce and discussions on the subject are controversial; no data exist for infection rates (IR) relative to drainage-days. For this reason, we conducted an observational study to determine time-dependent IRs and to perform a risk factor analysis. PATIENTS AND METHODS: All patients (n = 210) requiring an EVD or LD during an 18-month period in 2007 and 2008 were enrolled and characterized. Data on type and duration of drainage, ICP measurement, number of drainage manipulations, hospital stay and time point of MV were analysed statistically. RESULTS: A total of 34 MV cases were reported with 17 for each kind of drainage accounting for an IR of 7.5 and 24.7 MV/1000 EVD- and LD-days, respectively. Of these, 28/34 MV (82%) occurred within the first 12 days, and IRs were highest between days 4 and 9. Longer drainage duration (>5 and >9 days, respectively) was correlated with a significant lower risk of MV (p = 0.03; p < 0.001). In this study, significant risk factors for MV were LD [vs. EVD, OR: 2.3 (1.1-4.7); p = 0.01], a previous MV [OR: 7.0 (2.1-23.3); p = 0.002], and neoplasm [OR: 11.6 (3.4-39); p = 0.001]. Simultaneous drainage, ICP and a previous drainage showed no influence on infection. CONCLUSION: To the best of our knowledge, this study is the first to provide data on time dependency of EVD- and LD-associated MV-IR based on drainage-days. However, because of the limited scale of our study, it would be desirable to confirm these results in a more powerful larger study. In conclusion, we recommend that future efforts should be made to better identify preventable risk factors as well as to define time periods of higher risk for the difficult-to-diagnose MV infection as a first step in profiling high risk patients.


Assuntos
Cateteres de Demora/efeitos adversos , Derivações do Líquido Cefalorraquidiano/efeitos adversos , Infecção Hospitalar/etiologia , Drenagem/efeitos adversos , Encefalite/etiologia , Meningite/etiologia , Candida albicans/isolamento & purificação , Infecções do Sistema Nervoso Central/etiologia , Infecções do Sistema Nervoso Central/microbiologia , Ventrículos Cerebrais/microbiologia , Distribuição de Qui-Quadrado , Infecção Hospitalar/microbiologia , Encefalite/microbiologia , Feminino , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Unidades de Terapia Intensiva , Região Lombossacral , Masculino , Meningite/microbiologia , Estudos Prospectivos , Fatores de Risco , Estatísticas não Paramétricas , Fatores de Tempo
8.
Cell Death Differ ; 15(2): 312-21, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17992192

RESUMO

Mutant superoxide dismutase 1 (mtSOD1) causes dominantly inherited amyotrophic lateral sclerosis (ALS). The mechanism for mtSOD1 toxicity remains unknown. Two main hypotheses are the impairment of proteasomal function and chaperone depletion by misfolded mtSOD1. Here, we employed FRET/FLIM and biosensor imaging to quantitatively localize ubiquitination, as well as chaperone binding of mtSOD1, and to assess their effect on proteasomal and protein folding activities. We found large differences in ubiquitination and chaperone interaction levels for wild-type (wt) SOD1 versus mtSOD1 in intact single cells. Moreover, SOD1 ubiquitination levels differ between proteasomal structures and cytoplasmic material. Hsp70 binding and ubiquitination of wt and mtSOD1 species are highly correlated, demonstrating the coupled upregulation of both cellular detoxification mechanisms upon mtSOD1 expression. Biosensor imaging in single cells revealed that mtSOD1 expression alters cellular protein folding activity but not proteasomal function in the neuronal cell line examined. Our results provide the first cell-by-cell-analysis of SOD1 ubiquitination and chaperone interaction. Moreover, our study opens new methodological avenues for cell biological research on ALS.


Assuntos
Proteínas de Choque Térmico HSP70/metabolismo , Chaperonas Moleculares/metabolismo , Neurônios/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Superóxido Dismutase/metabolismo , Esclerose Lateral Amiotrófica , Animais , Linhagem Celular , Transferência Ressonante de Energia de Fluorescência , Microscopia de Fluorescência , Proteínas Mutantes/metabolismo , Dobramento de Proteína , Ratos , Superóxido Dismutase/genética , Superóxido Dismutase-1 , Ubiquitina/metabolismo , Ubiquitinação
9.
J Neurol Neurosurg Psychiatry ; 80(12): 1381-5, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19293173

RESUMO

OBJECTIVES: There are currently no data available on drain associated infection occurrence related to the number of drainage days (DD), and thus drain associated infection rates. Therefore, a prospective surveillance study was conducted to determine drain associated infection rates and DD of hospital acquired external ventricular drain (EVD) and lumbar drain (LD) associated meningitis/ventriculitis in a neurosurgery and a neurological intensive care unit. METHODS: All patients admitted in 2005 and 2006 were documented. Data on age, admitting diagnosis, type and duration of drain, duration of hospital stay and occurrence of meningitis were recorded and analysed statistically. RESULTS: A total of 1333 patients were included, amounting to 3023 DD. After exclusion of 15 contaminations, a total of 26 cases of meningitis were reported accounting for an overall device associated meningitis rate of 8.6 infections/1000 DD. Infections associated with LD seemed to occur more frequently (19.9/1000 DD) compared with EVD (6.3/1000 DD). The presence of intraventricular blood and previous trauma were significant risk factors for infection (p = 0.003; p = 0.04). Finally, length of stay was significantly longer in meningitis patients (p = 0.0003). Coagulase negative staphylococci were the main pathogen (56%) causing meningitis, followed by Staphylococcus aureus (25%). CONCLUSIONS: To the best of the authors' knowledge, this study represents the first to provide data on EVD as well as LD associated meningitis rates calculated per 1000 DD; a parameter that is well established for other invasive devices such as central venous and urinary tract catheters. However, further prospective studies are needed to investigate the possible risk factors for meningitis.


Assuntos
Cateteres de Demora/efeitos adversos , Infecção Hospitalar/etiologia , Drenagem/efeitos adversos , Encefalite/etiologia , Unidades de Terapia Intensiva , Meningite/etiologia , Procedimentos Neurocirúrgicos/efeitos adversos , Adulto , Idoso , Ventrículos Cerebrais , Infecção Hospitalar/epidemiologia , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Vigilância da População , Estudos Prospectivos , Fatores de Risco , Medula Espinal , Punção Espinal/efeitos adversos
10.
Eur J Clin Pharmacol ; 64(11): 1093-100, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18654767

RESUMO

OBJECTIVE: Physiological changes and local and systemic inflammation may affect plasma and tissue pharmacokinetics of antimicrobial agents in diabetics. The aim of the study was to investigate the penetration of linezolid into inflamed areas of infected diabetic foot wounds and the pharmacokinetics in the risk population of diabetics. METHODS: Pharmacokinetics and tissue penetration of linezolid into inflamed diabetic foot infection (DFI) tissue were determined at steady state in 15 patients with diabetes type 2 and DFI following administration of multiple oral doses of 600 mg given every 12 h. Second debridement was performed on days 4-6, 3 h after linezolid administration. Linezolid concentrations were determined in perinecrotic wound tissue of inflamed diabetic foot by high-performance liquid chromatography (HPLC). RESULTS: A mean maximum plasma concentration (C(max)) in plasma of 14.3 mg/L was attained at a median of 2.0 h [time to reach C(max) (T(max)) range 0.5-6.0 h). Area under the concentration time curve from zero to 12 h (AUC(0-12 h)) with a mean of 114.1 mgh/L and C(min) of 5.4 mg/L were achieved in patients with diabetes mellitus type 2. Penetration of linezolid into inflamed areas of DFI with tissue/plasma ratios of mean 101.7% [95% confidence interval (CI) 56; 148%] produced a mean concentration of 9.6 microg/g (95% CI 7.4; 11.8 microg/g) greater than those predicted to be effective against methicillin-resistant staphylococci [minimum concentration that inhibits 90% of organisms (MIC(90)) of 4 mg/L]. Tissue/plasma ratios correlated positive with systemic inflammation. CONCLUSION: Plasma pharmacokinetics of linezolid in diabetics and adequate levels in inflamed areas of diabetic foot wound suggest that an oral dose of 600 mg bd of linezolid provides effective concentrations for treating methicillin-resistant Staphylococcus aureus (MRSA) in DFI.


Assuntos
Acetamidas/farmacocinética , Anti-Infecciosos/farmacocinética , Pé Diabético/complicações , Inflamação/metabolismo , Oxazolidinonas/farmacocinética , Infecções dos Tecidos Moles/tratamento farmacológico , Infecções Cutâneas Estafilocócicas/tratamento farmacológico , Acetamidas/efeitos adversos , Idoso , Feminino , Humanos , Linezolida , Masculino , Resistência a Meticilina , Pessoa de Meia-Idade , Oxazolidinonas/efeitos adversos , Permeabilidade , Infecções dos Tecidos Moles/metabolismo , Infecções Cutâneas Estafilocócicas/metabolismo
11.
J Clin Invest ; 104(8): 1077-85, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10525046

RESUMO

Cardiotrophin-1 (CT-1), an IL-6-related cytokine, causes hypertrophy of cardiac myocytes and has pleiotropic effects on various other cell types, including motoneurons. Here, we analyzed systemic CT-1 effects in progressive motor neuronopathy (pmn) mice that suffer from progressive motoneuronal degeneration, muscle paralysis, and premature death. Administration of an adenoviral CT-1 vector to newborn pmn mice leads to sustained CT-1 expression in the injected muscles and bloodstream, prolonged survival of animals, and improved motor functions. CT-1-treated pmn mice showed a significantly reduced degeneration of facial motoneuron cytons and phrenic nerve myelinated axons. The terminal innervation of skeletal muscle, grossly disturbed in untreated pmn mice, was almost completely preserved in CT-1-treated pmn mice. The remarkable neuroprotection conferred by CT-1 might become clinically relevant if CT-1 side effects, including cardiotoxicity, could be circumvented by a more targeted delivery of this cytokine to the nervous system.


Assuntos
Adenoviridae/genética , Citocinas/genética , Terapia Genética , Doença dos Neurônios Motores/prevenção & controle , Fármacos Neuroprotetores/uso terapêutico , Animais , Axônios/efeitos dos fármacos , Células Cultivadas , Técnicas de Transferência de Genes , Humanos , Camundongos , Camundongos Mutantes , Doença dos Neurônios Motores/genética , Nervos Periféricos/efeitos dos fármacos
12.
Oncogene ; 36(11): 1597-1606, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27641335

RESUMO

The neural L1 transmembrane cell adhesion receptor of the immunoglobulin-like family is a target gene of Wnt-ß-catenin signaling in human colorectal cancer (CRC) cells and is expressed at the invasive edge of the tumor tissue. L1 overexpression in cultured CRC cells confers enhanced proliferation, motility and liver metastasis. We have analyzed the mechanisms of L1-mediated signaling in CRC cells by using various point mutations in the L1 ectodomain that are known to cause severe genetically inherited mental retardation disorders in patients. We found that all such L1 ectodomain mutations abolish the ability of L1 to confer metastatic properties in CRC cells. Using gene array analysis, we identified L1-mutation-specific gene expression signatures for the L1/H210Q and L1/D598N mutations. We identified CD10, a metalloprotease (neprilysin, neutral endopeptidase) and a gene that is specifically induced in CRC cells by L1 in an L1/H210Q mutation-specific manner. CD10 expression was required for the L1-mediated induction of cell proliferation, motility and metastasis, as suppression of CD10 levels in L1-expressing CRC cells abolished the L1 effects on CRC progression. The signaling from L1 to CD10 was mediated through the L1-ezrin-NF-κB pathway. In human CRC tissue L1 and CD10 were localized in partially overlapping regions in the more invasive areas of the tumor tissue. The results suggest that CD10 is a necessary component conferring the L1 effects in CRC cells. The identification of gene expression patterns of L1-domain-specific point mutations may provide novel markers and targets for interfering with L1-mediated CRC progression.


Assuntos
Neoplasias Colorretais/genética , Neprilisina/genética , Molécula L1 de Adesão de Célula Nervosa/genética , Mutação Puntual , Domínios e Motivos de Interação entre Proteínas/genética , Substituição de Aminoácidos , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Proteínas do Citoesqueleto/metabolismo , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica , Xenoenxertos , Humanos , Neoplasias Hepáticas/secundário , Masculino , Camundongos , NF-kappa B/metabolismo , Metástase Neoplásica , Neprilisina/metabolismo , Molécula L1 de Adesão de Célula Nervosa/química , Molécula L1 de Adesão de Célula Nervosa/metabolismo , Transdução de Sinais
13.
Oncogene ; 35(5): 549-57, 2016 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-25915847

RESUMO

Overactivation of Wnt-ß-catenin signaling, including ß-catenin-TCF target gene expression, is a hallmark of colorectal cancer (CRC) development. We identified the immunoglobulin family of cell-adhesion receptors member L1 as a ß-catenin-TCF target gene preferentially expressed at the invasive edge of human CRC tissue. L1 can confer enhanced motility and liver metastasis when expressed in CRC cells. This ability of L1-mediated metastasis is exerted by a mechanism involving ezrin and the activation of NF-κB target genes. In this study, we identified the secreted modular calcium-binding matricellular protein-2 (SMOC-2) as a gene activated by L1-ezrin-NF-κB signaling. SMOC-2 is also known as an intestinal stem cell signature gene in mice expressing Lgr5 in cells at the bottom of intestinal crypts. The induction of SMOC-2 expression in L1-expressing CRC cells was necessary for the increase in cell motility, proliferation under stress and liver metastasis conferred by L1. SMOC-2 expression induced a more mesenchymal like phenotype in CRC cells, a decrease in E-cadherin and an increase in Snail by signaling that involves integrin-linked kinase (ILK). SMOC-2 was localized at the bottom of normal human colonic crypts and at increased levels in CRC tissue with preferential expression in invasive areas of the tumor. We found an increase in Lgr5 levels in CRC cells overexpressing L1, p65 or SMOC-2, suggesting that L1-mediated CRC progression involves the acquisition of a stem cell-like phenotype, and that SMOC-2 elevation is necessary for L1-mediated induction of more aggressive/invasive CRC properties.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Neoplasias do Colo/genética , Mucosa Intestinal/metabolismo , Células-Tronco/metabolismo , Animais , Proteínas de Ligação ao Cálcio/biossíntese , Proteínas de Ligação ao Cálcio/metabolismo , Processos de Crescimento Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Progressão da Doença , Xenoenxertos , Humanos , Intestinos/patologia , Camundongos , Camundongos Nus , Metástase Neoplásica , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Células-Tronco/patologia , Ativação Transcricional , Via de Sinalização Wnt
14.
J Neurosci ; 20(13): 4992-5000, 2000 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10864957

RESUMO

Glial cell-line derived neurotrophic factor (GDNF) and its relative neurturin (NTN) are potent trophic factors for motoneurons. They exert their biological effects by activating the RET tyrosine kinase in the presence of a glycosyl-phosphatidylinositol-linked co-receptor, either GFRalpha1 or GFRalpha2. By whole-mount in situ hybridization on embryonic mouse spinal cord, we demonstrate that whereas Ret is expressed by nearly all motoneurons, Gfra1 and Gfra2 exhibit complex and distinct patterns of expression. Most motoneurons purified from Gfra1 null mutant mice had lost their responsiveness to both GDNF and NTN. However, a minority of them ( approximately 25%) retained their ability to respond to both factors, perhaps because they express GFRalpha2. Surprisingly, Gfra2(-/-) motoneurons showed normal survival responses to both GDNF and NTN. Thus, GFRalpha1, but not GFRalpha2, is absolutely required for the survival response of a majority of motoneurons to both GDNF and NTN. In accordance with the phenotype of the mutant motoneurons observed in culture we found the loss of distinct groups of motoneurons, identified by several markers, in the Gfra1(-/-) spinal cords but no gross defects in the Gfra2(-/-) mutant. During their natural programmed cell death period, motoneurons in the Gfra1(-/-) mutant mice undertook increased apoptosis. Taken together these findings support the existence of subpopulations of motoneuron with different trophic requirements, some of them being dependent on the GDNF family.


Assuntos
Proteínas de Drosophila , Neurônios Motores/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Receptores Proteína Tirosina Quinases/fisiologia , Medula Espinal/embriologia , Animais , Apoptose , Sobrevivência Celular/efeitos dos fármacos , Desenvolvimento Embrionário e Fetal , Regulação da Expressão Gênica no Desenvolvimento , Fator Neurotrófico Derivado de Linhagem de Célula Glial , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial , Glicosilfosfatidilinositóis/metabolismo , Hibridização In Situ , Camundongos , Camundongos Knockout , Neurônios Motores/citologia , Neurônios Motores/efeitos dos fármacos , Fatores de Crescimento Neural/farmacologia , Proteínas do Tecido Nervoso/farmacologia , Neurturina , Proteínas Proto-Oncogênicas/deficiência , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-ret , Receptores Proteína Tirosina Quinases/deficiência , Receptores Proteína Tirosina Quinases/genética , Medula Espinal/citologia
15.
J Clin Oncol ; 7(2): 236-44, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2915240

RESUMO

The optimal management for patients with stage II neuroblastoma has not yet been established. In order to determine the impact of adding chemotherapy and/or radiation therapy to surgery, we reviewed by questionnaire 156 patients with stage II neuroblastoma treated by 28 Childrens Cancer Study Group (CCSG) institutions from 1978 to 1985. Survival and progression-free survival (PFS) were analyzed by life-table methods with respect to age at diagnosis, site and size of primary tumor, spinal cord involvement, extent of initial resection, and treatment in addition to surgery. The overall 5-year survival was 96%; the PFS was 90%, similar to previous CCSG studies. Age at diagnosis had a small impact on PFS, with 92% PFS for patients less than 2 years of age at diagnosis, and 84% for those greater than 2 (P = .10). The only site with an adverse outcome was the head and neck (n = 11), with a PFS of 68% compared with 93% for the remaining sites (P = .02). Size of primary and intraspinal extension of primary did not affect PFS. The extent of resection and subsequent treatment with radiation therapy and/or chemotherapy did not affect the PFS. The outcome for 75 patients treated with surgery alone (6-year PFS, 89%) was not significantly different from that of 66 patients receiving radiation therapy (6-year PFS, 94%). There was no significant difference between 40 patients with gross or microscopic residual disease treated with surgery alone (PFS, 92%) and 59 patients with residual disease who also received radiation (PFS, 90%). Five of seven patients who progressed after surgery alone have been salvaged with further therapy and are now free of disease. One survives with disease, so that the 6-year survival is 98% for those treated initially with surgery alone, compared with 95% for those receiving radiation therapy and/or chemotherapy. These data suggest that surgery alone, even if complete resection is not achieved, is sufficient initial therapy for stage II neuroblastoma. The data also identify another stage of neuroblastoma, in addition to stage IV-S, for which almost all patients have a favorable prognosis because their tumor may be biologically limited in growth.


Assuntos
Neuroblastoma/terapia , Neoplasias Abdominais/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Neuroblastoma/mortalidade , Neuroblastoma/patologia , Prognóstico , Neoplasias Torácicas/terapia
16.
J Clin Oncol ; 14(9): 2417-26, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8823319

RESUMO

PURPOSE: To compare event-free survival (EFS) for patients with stage IV neuroblastoma who were treated with induction chemotherapy followed by additional courses of the same chemotherapy or by intensive chemoradiotherapy and autologous bone marrow transplantation (ABMT). METHODS: Two hundred seven children who were diagnosed with stage IV neuroblastoma after 1 year of age were given five to seven courses of induction chemotherapy consisting of cisplatin, etoposide, doxorubicin, and cyclophosphamide (CCC-321-P2). This chemotherapy was continued for 13 total courses for some patients, whereas intensive chemoradiotherapy with ABMT was given to others (CCG-321-P3). The decision to continue chemotherapy versus to consolidate with chemoradiotherapy was not randomized but was made by parents and physicians. Marrow used for ABMT was purged ex vivo and was free of immunocytologically detectable neuroblastoma cells. RESULTS: One hundred fifty-nine of 207 patients (77%) remained event-free during induction therapy. Of these, 67 received chemoradiotherapy/ABMT (CCG-321-P3) and 74 continued chemotherapy (CCG-321-P2). Using Cox regression analysis, the relative risk (RR) of an event after chemoradiotherapy/ABMT was estimated to be 58% of that for patients who continued chemotherapy (P = .01). Similarly, Kaplan-Meier analysis estimated EFS at four years for the chemoradiotherapy/ABMT and chemotherapy groups to be 40% and 19% respectively (P = .019). Subgroups appearing to benefit from chemoradiotherapy/ABMT were those with only a partial tumor response to induction chemotherapy (RR = 0.43; P = .008; EFS, 29% v 6%) and those whose tumors had amplification of the N-myc gene (RR = 0.26; P = .112; EFS, 67% v 0%). CONCLUSION: Consolidation with intensive, myeloablative chemoradiotherapy followed by purged ABMT may be more effective than continuing chemotherapy for patients with stage IV neuroblastoma.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Medula Óssea , Neuroblastoma/secundário , Neuroblastoma/terapia , Adolescente , Purging da Medula Óssea , Criança , Pré-Escolar , Terapia Combinada , Intervalo Livre de Doença , Humanos , Lactente , Neuroblastoma/tratamento farmacológico , Neuroblastoma/mortalidade , Análise de Regressão , Taxa de Sobrevida , Transplante Autólogo
17.
J Clin Oncol ; 18(1): 18-26, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10623689

RESUMO

PURPOSE: To determine prospectively whether surgery alone is sufficient therapy for Evans stages I and II neuroblastoma and to define biologic and clinical features having prognostic potential for this group. PATIENTS AND METHODS: Between June 1989 and August 1995, 374 eligible children (age range, 0 to 18 years) with newly diagnosed stage I (n = 141) and stage II (n = 233) neuroblastoma were registered onto Children's Cancer Group trial 3881. Surgical resection was the only primary therapy except in cases with spinal cord compression, where radiation therapy was allowed. Event-free survival (EFS) and overall survival (OS) were analyzed by life-table methods according to clinical and biologic features. RESULTS: EFS and OS (mean +/- SE) for all stage I patients were 93% +/- 3.0% and 99% +/- 1.0%, respectively, compared with 81% +/- 4.0% and 98% +/- 2. 0%, respectively, for stage II patients. The significantly higher recurrence rate among stage II patients was managed successfully in 38 of 43 children with either surgery or multimodality treatment. There was one death among stage I patients and six among stage II. For stage II patients tumor MYCN gene amplication, unfavorable histopathology, an age greater than 2 years, and positive lymph nodes predicted a lower OS (P <.05). CONCLUSION: Children with stages I and II neuroblastoma have 98% survival with surgery alone as primary therapy. Supplemental treatment was necessary in only 10% of stage I patients and 20% of stage II patients. In children with localized neuroblastoma, a subset of patients that are at higher risk for death can be defined as those with stage II disease who have tumor MYCN amplification or who are >/= 2 years of age with either unfavorable histopathology or positive lymph nodes.


Assuntos
Biomarcadores Tumorais , Amplificação de Genes , Genes myc/genética , Neuroblastoma/diagnóstico , Neuroblastoma/cirurgia , Adolescente , Análise de Variância , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Humanos , Lactente , Recém-Nascido , Tábuas de Vida , Masculino , Metástase Neoplásica , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Neuroblastoma/mortalidade , Prognóstico , Estudos Prospectivos , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fatores de Risco , Taxa de Sobrevida , Estados Unidos/epidemiologia
18.
J Clin Oncol ; 12(11): 2382-9, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7964954

RESUMO

PURPOSE: We have compared the toxicity, relapse rate, and progression-free survival (PFS) of high-risk neuroblastoma patients receiving identical induction therapy and myeloablative chemotherapy plus total-body irradiation (TBI) followed by allogeneic or autologous purged bone marrow transplantation (BMT). PATIENTS AND METHODS: Fifty-six patients with high-risk neuroblastoma underwent BMT at investigator and parent option if they did not have progressive disease after induction chemotherapy with cisplatin, cyclophosphamide, doxorubicin, and etoposide. After surgery and local radiation to residual tumor, myeloablative therapy consisting of etoposide, melphalan, cisplatin, and TBI was given followed by BMT. Patients with human leukocyte antigen (HLA)-compatible siblings received allogeneic bone marrow (n = 20). The remaining patients (n = 36) received autologous bone marrow that had undergone multimodality purging and had no remaining detectable tumor cells by immunocytology. RESULTS: Four of 20 allogeneic patients had a treatment-related death, compared with three of 36 autologous patients (P = .21). The relapse rate among allogeneic BMT patients was 69%, compared with 46% for autologous BMT patients (P = .14). The estimated PFS rates 4 years after BMT were 25% for allogeneic BMT patients and 49% for autologous BMT patients (P = .051). CONCLUSION: Overall outcome for patients with neuroblastoma given this same induction therapy followed by autologous purged marrow was similar to that with allogeneic marrow, although bias in patients selection cannot be excluded in a nonrandomized comparison.


Assuntos
Transplante de Medula Óssea , Neuroblastoma/terapia , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Medula Óssea/efeitos adversos , Criança , Pré-Escolar , Terapia Combinada , Esquema de Medicação , Seguimentos , Humanos , Lactente , Recidiva Local de Neoplasia , Neuroblastoma/tratamento farmacológico , Neuroblastoma/patologia , Projetos Piloto , Prognóstico , Transplante Autólogo , Transplante Homólogo , Irradiação Corporal Total
19.
J Clin Oncol ; 18(6): 1260-8, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10715296

RESUMO

PURPOSE: A prospective Children's Cancer Group study, CCG-3881, has been completed to determine if a more accurate prediction of prognosis by biologic features can identify subgroups of infants with stage IV neuroblastoma (NBL) who require differing intensities of treatment. PATIENTS AND METHODS: One hundred thirty-four infants were registered from June 1989 to August 1995, with a median follow-up of 47.1 months (range, 0 to 88 months). The biologic factors examined were tumor MYCN copy number, Shimada histopathologic classification, serum ferritin, and bone marrow immunocytology (sensitivity, one tumor cell per 10(5) bone marrow cells). Patients treated on CCG-3881 (n = 116) received four-drug chemotherapy for 9 months (cisplatin, cyclophosphamide, doxorubicin, and etoposide), with surgery and local radiation to residual disease. After January 1991, all subsequent infants with tumor MYCN amplification (n = 18) were transferred after one cycle of therapy to the high-risk CCG-3891 protocol (open January 1991 to April 1996) for more intensive treatment. RESULTS: The 3-year event-free survival (EFS) and overall survival (mean +/- SD) for the 134 infants were 63% +/- 5% and 71% +/- 5%, respectively. Patients whose tumors were without MYCN amplification had a 93% +/- 4% 3-year EFS, whereas those with amplified MYCN had a 10% +/- 7% 3-year EFS (P <. 0001). Each of the other biologic features studied had prognostic significance in univariate analysis but not after stratifying by MYCN copy number. CONCLUSION: Infants less than 1 year of age at diagnosis with stage IV NBL have a much improved outcome compared with children >/= 1 year of age. Nonamplified MYCN tumors identify a group of infants with a 93% +/- 4% EFS, whereas amplified MYCN copy number clearly identifies patients who are unlikely to survive despite intensive chemotherapy.


Assuntos
Fatores Biológicos/metabolismo , Neuroblastoma/metabolismo , Neuroblastoma/mortalidade , Proteínas Proto-Oncogênicas c-myc/metabolismo , Medula Óssea/patologia , Pré-Escolar , Progressão da Doença , Feminino , Ferritinas/sangue , Humanos , Lactente , Masculino , Estadiamento de Neoplasias , Neuroblastoma/patologia , Neuroblastoma/terapia , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos
20.
J Clin Oncol ; 16(12): 3744-51, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9850017

RESUMO

PURPOSE: National Wilms' Tumor Study (NWTS)-4 was designed to evaluate the efficacy, toxicity, and cost of the administration of different regimens for the treatment of Wilms' tumor (WT). PATIENTS AND METHODS: Between August 6, 1986 and September 1, 1994, 905 previously untreated children aged younger than 16 years with stage II favorable histology (FH) WT (low-risk [LR]), stages III to IV FH WT, or stages I to IV clear-cell sarcoma of the kidney (high-risk[HR]) were randomized after the completion of 6 months of chemotherapy to discontinue (short) or continue for 9 additional months (long) treatment with chemotherapy regimens that included vincristine and either divided-dose (standard [STD]) courses (5 days) or single-dose (pulse-intensive [PI]) treatment with dactinomycin. HR patients also received either divided-dose (STD) courses (3 days) or single-dose (PI) treatment with doxorubicin. RESULTS: The 4-year relapse-free survival (RFS) rates after the second randomization for LR patients were 83.7% for the 190 patients treated with short and 88.2% for the 187 patients treated with long chemotherapy (P = .11). The 4-year RFS rates after the second randomization for HR FH patients were 89.7% for the 256 patients treated with short and 88.8% for the 246 patients treated with long chemotherapy (P = .87). The charge for treatment with the short PI treatment regimens for all children with stages I through IV FH WT was approximately one half of that with the long STD treatment regimens. CONCLUSION: The short administration schedule for the treatment of children with WT is no less effective than the long administration schedule and can be administered at a substantially lower total treatment cost.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/economia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cuidado Periódico , Custos de Cuidados de Saúde , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/economia , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Neoplasias Embrionárias de Células Germinativas/economia , Adolescente , Antibióticos Antineoplásicos/administração & dosagem , Antineoplásicos Fitogênicos/administração & dosagem , Criança , Pré-Escolar , Análise Custo-Benefício , Dactinomicina/administração & dosagem , Doxorrubicina/administração & dosagem , Esquema de Medicação , Feminino , Humanos , Lactente , Neoplasias Renais/patologia , Masculino , Estadiamento de Neoplasias , Neoplasias Embrionárias de Células Germinativas/secundário , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Estados Unidos , Vincristina/administração & dosagem , Tumor de Wilms/tratamento farmacológico , Tumor de Wilms/economia
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