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1.
Stud Mycol ; 104: 1-85, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37351542

RESUMEN

Fruiting bodies (sporocarps, sporophores or basidiomata) of mushroom-forming fungi (Agaricomycetes) are among the most complex structures produced by fungi. Unlike vegetative hyphae, fruiting bodies grow determinately and follow a genetically encoded developmental program that orchestrates their growth, tissue differentiation and sexual sporulation. In spite of more than a century of research, our understanding of the molecular details of fruiting body morphogenesis is still limited and a general synthesis on the genetics of this complex process is lacking. In this paper, we aim at a comprehensive identification of conserved genes related to fruiting body morphogenesis and distil novel functional hypotheses for functionally poorly characterised ones. As a result of this analysis, we report 921 conserved developmentally expressed gene families, only a few dozens of which have previously been reported to be involved in fruiting body development. Based on literature data, conserved expression patterns and functional annotations, we provide hypotheses on the potential role of these gene families in fruiting body development, yielding the most complete description of molecular processes in fruiting body morphogenesis to date. We discuss genes related to the initiation of fruiting, differentiation, growth, cell surface and cell wall, defence, transcriptional regulation as well as signal transduction. Based on these data we derive a general model of fruiting body development, which includes an early, proliferative phase that is mostly concerned with laying out the mushroom body plan (via cell division and differentiation), and a second phase of growth via cell expansion as well as meiotic events and sporulation. Altogether, our discussions cover 1 480 genes of Coprinopsis cinerea, and their orthologs in Agaricus bisporus, Cyclocybe aegerita, Armillaria ostoyae, Auriculariopsis ampla, Laccaria bicolor, Lentinula edodes, Lentinus tigrinus, Mycena kentingensis, Phanerochaete chrysosporium, Pleurotus ostreatus, and Schizophyllum commune, providing functional hypotheses for ~10 % of genes in the genomes of these species. Although experimental evidence for the role of these genes will need to be established in the future, our data provide a roadmap for guiding functional analyses of fruiting related genes in the Agaricomycetes. We anticipate that the gene compendium presented here, combined with developments in functional genomics approaches will contribute to uncovering the genetic bases of one of the most spectacular multicellular developmental processes in fungi. Citation: Nagy LG, Vonk PJ, Künzler M, Földi C, Virágh M, Ohm RA, Hennicke F, Bálint B, Csernetics Á, Hegedüs B, Hou Z, Liu XB, Nan S, M. Pareek M, Sahu N, Szathmári B, Varga T, Wu W, Yang X, Merényi Z (2023). Lessons on fruiting body morphogenesis from genomes and transcriptomes of Agaricomycetes. Studies in Mycology 104: 1-85. doi: 10.3114/sim.2022.104.01.

2.
Cancer Metastasis Rev ; 37(2-3): 245-255, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29808460

RESUMEN

In the past decades, a vast amount of data accumulated on the role of lipid signaling pathways in the progression of malignant melanoma, the most metastatic/aggressive human cancer type. Genomic studies identified that PTEN loss is the leading factor behind the activation of the PI3K-signaling pathway in melanoma, mutations of which are one of the main resistance mechanisms behind target therapy failures. On the other hand, illegitimate expressions of megakaryocytic genes p12-lipoxyganse, cyclooxygenase-2, and phosphodiestherase-2/autotaxin (ATX) are mostly involved in the regulation of motility signaling in melanoma through various G-protein-coupled bioactive lipid receptors. Furthermore, endocannabinoid signaling can also be a novel paracrine survival factor in melanoma. Last but not least, prenylation inhibitors acting even on mutated small GTP-ases, such as NRAS of melanoma may offer novel therapeutic opportunities. As regards melanoma, the most effective therapy nowadays is immunotherapy, with the resistance mechanisms also possibly involving the lipid signaling activities of melanoma cells, which further supports the idea of their being therapeutic targets.


Asunto(s)
Metabolismo de los Lípidos , Melanoma/metabolismo , Melanoma/patología , Transducción de Señal , Animales , Ácido Araquidónico/metabolismo , Ciclooxigenasa 2/metabolismo , Progresión de la Enfermedad , Endocannabinoides/metabolismo , Predisposición Genética a la Enfermedad , Humanos , Lisofosfolípidos/metabolismo , Melanoma/etiología , Redes y Vías Metabólicas , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfolipasas/metabolismo , Hidrolasas Diéster Fosfóricas , Prenilación , Prostaglandinas/metabolismo , Receptores del Ácido Lisofosfatídico/metabolismo
3.
Br J Cancer ; 112(5): 783-92, 2015 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-25633038

RESUMEN

BACKGROUND: Estimating the prognosis in malignant pleural mesothelioma (MPM) remains challenging. Thus, the prognostic relevance of Ki67 was studied in MPM. METHODS: Ki67 index was determined in a test cohort of 187 cases from three centres. The percentage of Ki67-positive tumour cells was correlated with clinical variables and overall survival (OS). The prognostic power of Ki67 index was compared with other prognostic factors and re-evaluated in an independent cohort (n=98). RESULTS: Patients with Ki67 higher than median (>15%) had significantly (P<0.001) shorter median OS (7.5 months) than those with low Ki67 (19.1 months). After multivariate survival analyses, Ki67 proved to be-beside histology and treatment-an independent prognostic marker in MPM (hazard ratio (HR): 2.1, P<0.001). Interestingly, Ki67 was prognostic exclusively in epithelioid (P<0.001) but not in non-epithelioid subtype. Furthermore, Ki67 index was significantly lower in post-chemotherapy samples when compared with chemo-naive cases. The prognostic power was comparable to other recently published prognostic factors (CRP, fibrinogen, neutrophil-to-leukocyte ratio (NLR) and nuclear grading score) and was recapitulated in the validation cohort (P=0.048). CONCLUSION: This multicentre study demonstrates that Ki67 is an independent and reproducible prognostic factor in epithelioid but not in non-epithelioid MPM and suggests that induction chemotherapy decreases the proliferative capacity of MPM.


Asunto(s)
Células Epitelioides/patología , Antígeno Ki-67/metabolismo , Neoplasias Pulmonares/mortalidad , Mesotelioma/mortalidad , Neoplasias Pleurales/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Células Epitelioides/metabolismo , Femenino , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Masculino , Mesotelioma/tratamiento farmacológico , Mesotelioma/metabolismo , Mesotelioma/patología , Mesotelioma Maligno , Persona de Mediana Edad , Neoplasias Pleurales/tratamiento farmacológico , Neoplasias Pleurales/metabolismo , Neoplasias Pleurales/patología , Análisis de Supervivencia , Resultado del Tratamiento
4.
Cancer Metastasis Rev ; 32(3-4): 493-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23636347

RESUMEN

Metastasis of human cancer is an organ-selective process that is determined by anatomical and biological factors as well as by specific microenvironmental properties. Dissemination of visceral malignancies to the skin is rather rare and usually occurs in a later stage of the disease. Using statistical approaches, both positive (renal and lung cancers) and negative (pancreatic and liver cancers) organ preferences can be identified in a variety of cancers. While certain cancer types are characterized by random distribution for skin metastasis (liver cancer), a number of cancers demonstrate a colonization preference to the region of origin: lung cancer to the supradiaphragmatic (mostly chest) and colorectal cancers to the infradiaphragmatic (abdominal) skin regions. In certain cases, however, skin metastasis develops more frequently at specific distant locations, as evidenced by the dissemination of renal cancer at the head and neck region. These findings are clinically relevant and useful especially in patients where skin metastasis is the first indication of a malignancy. Nevertheless, it is a strong argument for the predominant role of microenvironmental factors in cancer dissemination. On the other hand, skin metastases of visceral cancers provide a unique model to analyze the pathomechanisms determining organ selectivity, including the organ-specific vascularization, the dermatome-specific innervation, or immunological and developmental factors.


Asunto(s)
Neoplasias/patología , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/secundario , Humanos , Neoplasias/diagnóstico , Neovascularización Patológica , Especificidad de Órganos , Prevalencia , Neoplasias Cutáneas/epidemiología
5.
Br J Cancer ; 110(4): 984-90, 2014 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-24434429

RESUMEN

BACKGROUND: To investigate the clinical utility of pretreatment plasma fibrinogen levels in malignant pleural mesothelioma (MPM) patients. METHODS: A retrospective multicenter study was performed in histologically proven MPM patients. All fibrinogen levels were measured at the time of diagnosis and clinical data were retrospectively collected after approval of the corresponding ethics committees. RESULTS: In total, 176 MPM patients (mean age: 63.5 years ± 10.4 years, 38 females and 138 males) were analysed. Most patients (n=154, 87.5%) had elevated (≥ 390 mg dl(-1)) plasma fibrinogen levels. When patients were grouped by median fibrinogen, patients with low level (≤ 627 mg dl(-1)) had significantly longer overall survival (OS) (19.1 months, confidence interval (CI) 14.5-23.7 months) when compared with those with high level (OS 8.5; CI 6.2-10.7 months). In multivariate survival analyses, fibrinogen was found to be an independent prognostic factor (hazard ratio 1.81, CI 1.23-2.65). Most interestingly, fibrinogen (cutoff 75th percentile per 750 mg dl(-1)) proved to be a predictive biomarker indicating treatment benefit achieved by surgery within multimodality therapy (interaction term: P=0.034). Accordingly, only patients below the 75th percentile benefit from surgery within multimodality therapy (31.3 vs 5.3 months OS). CONCLUSIONS: Fibrinogen is a novel independent prognostic biomarker in MPM. Most importantly, fibrinogen predicted treatment benefit achieved by surgery within multimodality therapy.


Asunto(s)
Biomarcadores de Tumor/sangre , Fibrinógeno/análisis , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/cirugía , Mesotelioma/sangre , Mesotelioma/cirugía , Terapia Combinada , Femenino , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Masculino , Mesotelioma/tratamiento farmacológico , Mesotelioma Maligno , Persona de Mediana Edad , Neoplasias Pleurales/sangre , Neoplasias Pleurales/tratamiento farmacológico , Neoplasias Pleurales/cirugía , Pronóstico , Estudios Retrospectivos
6.
Br J Cancer ; 107(12): 1978-86, 2012 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-23169291

RESUMEN

BACKGROUND: Activins control the growth of several tumour types including thoracic malignancies. In the present study, we investigated their expression and function in malignant pleural mesothelioma (MPM). METHODS: The expression of activins and activin receptors was analysed by quantitative PCR in a panel of MPM cell lines. Activin A expression was further analysed by immunohistochemistry in MPM tissue specimens (N=53). Subsequently, MPM cells were treated with activin A, activin receptor inhibitors or activin-targeting siRNA and the impact on cell viability, proliferation, migration and signalling was assessed. RESULTS: Concomitant expression of activin subunits and receptors was found in all cell lines, and activin A was overexpressed in most cell lines compared with non-malignant mesothelial cells. Similarly, immunohistochemistry demonstrated intense staining of tumour cells for activin A in a subset of patients. Treatment with activin A induced SMAD2 phosphorylation and stimulated clonogenic growth of mesothelioma cells. In contrast, treatment with kinase inhibitors of activin receptors (SB-431542, A-8301) inhibited MPM cell viability, clonogenicity and migration. Silencing of activin A expression by siRNA oligonucleotides further confirmed these results and led to reduced cyclin D1/3 expression. CONCLUSION: Our study suggests that activin A contributes to the malignant phenotype of MPM cells via regulation of cyclin D and may represent a valuable candidate for therapeutic interference.


Asunto(s)
Activinas/antagonistas & inhibidores , Antineoplásicos/farmacología , Ciclina D/metabolismo , Mesotelioma/metabolismo , Mesotelioma/patología , Neoplasias Pleurales/metabolismo , Neoplasias Pleurales/patología , Western Blotting , Movimiento Celular , Proliferación Celular , Supervivencia Celular , Ciclina D/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica , Silenciador del Gen , Humanos , Inmunohistoquímica , Mesotelioma/tratamiento farmacológico , Fenotipo , Fosforilación/efectos de los fármacos , Neoplasias Pleurales/tratamiento farmacológico , ARN Interferente Pequeño/farmacología , Reacción en Cadena en Tiempo Real de la Polimerasa , Transducción de Señal/efectos de los fármacos , Proteína Smad2/metabolismo , Ensayo de Tumor de Célula Madre , Regulación hacia Arriba
7.
Phys Biol ; 9(1): 016010, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22313673

RESUMEN

Cell invasion from an aggregate into a surrounding extracellular matrix (ECM) is an important process during development disease, e.g., vascular network assembly or tumor progression. To describe the behavior emerging from autonomous cell motility, cell-cell adhesion and contact guidance by ECM filaments, we propose a suitably modified cellular Potts model. We consider an active cell motility process in which internal polarity is governed by a positive feedback from cell displacements, a mechanism that can result in highly persistent motion when constrained by an oriented ECM structure. The model allows us to explore the interplay between haptotaxis, matrix degradation and active cell movement. We show that for certain conditions the cells are able to both invade the ECM and follow the ECM tracks. Furthermore, we argue that enforcing mechanical equilibrium within a bulk cell mass is of key importance in multicellular simulations.


Asunto(s)
Neoplasias Encefálicas/patología , Adhesión Celular , Matriz Extracelular/fisiología , Modelos Biológicos , Animales , Neoplasias Encefálicas/ultraestructura , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Colágeno Tipo I/metabolismo , Células Endoteliales/citología , Humanos , Invasividad Neoplásica/patología , Ratas
8.
Br J Pharmacol ; 172(4): 1148-63, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25363319

RESUMEN

BACKGROUND AND PURPOSE: The clinical effects of anti-angiogenic agents remain controversial. Therefore, elucidating the pharmacological properties of these compounds is a pivotal issue. EXPERIMENTAL APPROACH: The effects of treatment with sunitinib on tumour and normal tissues of mice bearing C-26 adenocarcinoma cells were analysed by matrix-assisted laser desorption ionization MS imaging (MALDI-MSI). Expression of the key targets of sunitinib--angiogenic receptors--was studied by immunofluorescent labelling. KEY RESULTS: MALDI-MS assays showed that sunitinib and its fragment ions were present throughout tumour and normal tissues. Major metabolites were identified in blood and solid tissues, while minor drug metabolites were detectable only in blood. Tumour growth and intratumour VEGF receptor-2 expressions were significantly reduced in sunitinib-treated mice, while the expression of the other targeted receptors, PDGF receptor -α or -ß and fibroblast growth factor receptor-1, remained unaffected. Within tumour tissue, the close proximity of sunitinib metabolites to the precursor ion suggested in situ metabolism of the administered drug. There were intratumour areas where the signal intensity of sunitinib correlated with expression of VEGF receptor-2. CONCLUSIONS AND IMPLICATIONS: This is the first study that demonstrates MALDI-MSI is a versatile platform to study the intratumour localization of an unlabelled anti-angiogenic drug. The combination of MALDI-MSI and immunofluorescence analysis can provide further insights into the molecular interaction of drug compounds and their targets within tumour tissue.


Asunto(s)
Adenocarcinoma/metabolismo , Inhibidores de la Angiogénesis/farmacocinética , Indoles/farmacocinética , Pirroles/farmacocinética , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Inhibidores de la Angiogénesis/sangre , Inhibidores de la Angiogénesis/farmacología , Inhibidores de la Angiogénesis/uso terapéutico , Animales , Línea Celular Tumoral , Femenino , Indoles/sangre , Indoles/farmacología , Indoles/uso terapéutico , Riñón/metabolismo , Hígado/metabolismo , Ratones Endogámicos BALB C , Pirroles/sangre , Pirroles/farmacología , Pirroles/uso terapéutico , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Sunitinib , Carga Tumoral/efectos de los fármacos , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo
9.
Eur J Pharmacol ; 98(1): 79-91, 1984 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-6325212

RESUMEN

Experiments were performed to examine the acute effects of cholecystokinin octapeptides and fragments on the active and passive avoidance behaviour of rats following peripheral and central administration. Both the sulphated (CCK-8-SE) and non-sulphated cholecystokinin octapeptide (CCK-8-NS) and also the COOH-terminal tetra-, penta-, hexa- and heptapeptides of cholecystokinin octapeptide facilitated the extinction of active avoidance behaviour and retention of passive avoidance behaviour. This latter effect of cholecystokinin octapeptides was reversed by anxiolytic chlordiazepoxide pretreatment, showing that in these test situations cholecystokinin octapeptides are able to modify fear-motivation or arousal of the animals; their effect is at least partly similar to that of the neuroleptic substance haloperidol. Subcutaneous treatment with CCK-8-SE or CCK-8-NS appeared to be 3-10 times more effective than intraperitoneal treatment. Following intracerebroventricular administration, 100-300 times lower doses were needed to cause a behavioural effect similar to that after subcutaneous injection. Microinjection of CCK-8-SE or CCK-8-NS in the fmol dose range into the nucleus accumbens facilitated the extinction of active avoidance behaviour and attenuated the retention of passive avoidance behaviour, while microinjection of these peptides into the central amygdaloid nucleus caused opposite effects on these behavioural tests. It seems that the neuroleptic-like effects of cholecystokinin octapeptides are mediated through the nucleus accumbens, and the opposite action (non neuroleptic-like) through the central amygdaloid nucleus.


Asunto(s)
Reacción de Prevención/efectos de los fármacos , Sincalida/farmacología , Amígdala del Cerebelo/efectos de los fármacos , Animales , Clordiazepóxido/farmacología , Haloperidol/farmacología , Inyecciones Intravenosas , Inyecciones Intraventriculares , Masculino , Actividad Motora/efectos de los fármacos , Núcleo Accumbens/efectos de los fármacos , Ratas , Ratas Endogámicas , Sincalida/administración & dosificación , Relación Estructura-Actividad , Factores de Tiempo
10.
J Neurosurg ; 92(3): 428-34, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10701529

RESUMEN

OBJECT: The motility and doubling of human glioblastoma cells were investigated by means of statistical evaluation of large sets of data obtained using computer-aided videomicroscopy. METHODS: Data were obtained on cells in four established glioblastoma cell lines and also on primary tumor cells cultured from fresh surgical samples. Growth rates and cell cycle times were measured in individual microscopic fields. The averages of cell cycle time and the duplication time for the recorded cell populations were 26.2 +/- 5.6 hours and 38 +/- 4 hours, respectively. With these parameters, no significant differences among the cell lines were revealed. Also, there was no correlation in the cell cycle time of a parent cell and its progeny in any of the cultures. Statistical analysis of cell locomotion revealed an exponential distribution of cell velocities and strong fluctuations in individual cell velocities across time. The average velocity values ranged from 4.2 to 27.9 micro/hour. In spite of the uniform histopathological classification of the four tumors, each cell line produced by these tumors displayed distinct velocity distribution profiles and characteristic average velocity values. A comparison of recently established primary cultures with cell lines that had propagated multiple times indicated that cells derived from different tumors sustain their characteristic locomotor activity after several passages. CONCLUSIONS: It can be inferred from the data that statistical evaluation of physical parameters of cell locomotion can provide additional tools for tumor diagnosis.


Asunto(s)
Neoplasias Encefálicas/patología , División Celular/fisiología , Movimiento Celular/fisiología , Glioblastoma/patología , Microscopía por Video , Interpretación Estadística de Datos , Diseño de Equipo , Humanos , Procesamiento de Imagen Asistido por Computador/instrumentación , Técnicas In Vitro , Microscopía por Video/instrumentación , Células Tumorales Cultivadas
11.
J Pharm Biomed Anal ; 3(4): 303-13, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-16867665

RESUMEN

High resolution FT-IR data are given on five known and two uncharacterized modifications of cimetidine. On the basis of the chronological order of publications and the usual nomenclature, an attempt is made to clear up the uncertainty concerning the names of the various modifications. An attempt is made to rationalize the spectroscopic data characterizing the given modifications. The anhydrous and the monohydrate modifications are discussed separately, together with those changes which occur on the dehydration of the monohydrates without melting.

12.
J Pharm Biomed Anal ; 1(4): 497-506, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-16867788

RESUMEN

The application of chemical reactions in conjunction with spectrometric and chromatographic methods is exemplified by the formation of 2-nitrophenylhydrazide derivatives for the spectrometric assay of carboxylic acids; silylation and trifluoroacetylation of drugs for gas chromatography; selective reduction of steroid ketones for their IR spectrometric identification; the use of epoxidation in discriminating between saturated and unsaturated steroids in gas chromatography; increasing the selectivity and sensitivity of the spectrometric and gas chromatographic determination of isomeric Delta4- and Delta5-3-ethylenedioxy steroids by treatment with hydrochloric acid; and the use of the same reagent in the difference spectrometric determination of 2,5-dimethyl-alpha-ethyl benzhydrol.

13.
J Pharm Biomed Anal ; 7(5): 563-9, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2490760

RESUMEN

The polymorphic modifications of famotidine are described and characterized by their spectroscopic (infrared, X-ray) and some physico-chemical data. In addition to the standard physico-chemical data (melting point, solubility, bulk density) some further properties influencing its use in pharmaceutical technology are also characterized. The methods used to prepare the morphologically homogeneous modifications are also given.


Asunto(s)
Famotidina/química , Rastreo Diferencial de Calorimetría , Estabilidad de Medicamentos , Modelos Moleculares , Espectrofotometría Infrarroja , Termodinámica , Difracción de Rayos X
14.
J Pharm Biomed Anal ; 11(11-12): 1219-26, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8123737

RESUMEN

Impurities in drugs are classified on the basis of the types of side-reactions in drug syntheses resulting in their formation. This is shown by summarizing the authors' earlier results in the field of impurity profiling of 19-nor-steroids, ethynodiol diacetate, mazipredone, pipecuronium bromide, flumecinol, enalapril, pyridinol carbamate, phenylbutazone, thymotrinan and some new results related to danazol and famotidine.


Asunto(s)
Química Farmacéutica , Contaminación de Medicamentos , Preparaciones Farmacéuticas/síntesis química , Cromatografía de Gases , Cromatografía Líquida de Alta Presión , Cromatografía en Capa Delgada , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Preparaciones Farmacéuticas/análisis , Preparaciones Farmacéuticas/aislamiento & purificación , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta
15.
Cell Death Differ ; 20(6): 823-33, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23449395

RESUMEN

Interleukin-24 (IL-24), a member of the IL-10 cytokine family whose physiological function remains largely unknown, has been shown to induce apoptosis when expressed in an adenoviral background. It is yet little understood, why IL-24 alone induced apoptosis only in a limited number of tumor cell lines. Analyzing an influenza A virus vector expressing IL-24 for its oncolytic potential revealed enhanced pro-apoptotic activity of the chimeric virus compared with virus or IL-24 alone. Interestingly, IL-24-mediated enhancement of influenza-A-induced apoptosis did not require viral replication but critically depended on toll-like receptor 3 (TLR3) and caspase-8. Immunoprecipitation of TLR3 showed that infection by influenza A virus induced formation of a TLR3-associated signaling complex containing TRIF, RIP1, FADD, cFLIP and pro-caspase-8. Co-administration of IL-24 decreased the presence of cFLIP in the TLR3-associated complex, converting it into an atypical, TLR3-associated death-inducing signaling complex (TLR3 DISC) that induced apoptosis by enabling caspase-8 activation at this complex. The sensitizing effect of IL-24 on TLR3-induced apoptosis, mediated by influenza A virus or the TLR3-specific agonist poly(I:C), was also evident on tumor spheroids. In conclusion, rather than acting as an apoptosis inducer itself, IL-24 sensitizes cancer cells to TLR-mediated apoptosis by enabling the formation of an atypical DISC which, in the case of influenza A virus or poly(I:C), is associated with TLR3.


Asunto(s)
Apoptosis/fisiología , Interleucinas/biosíntesis , Interleucinas/farmacología , Neoplasias/terapia , Viroterapia Oncolítica/métodos , Receptor Toll-Like 3/metabolismo , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Caspasa 8/metabolismo , Línea Celular Tumoral , Chlorocebus aethiops , Citocinas/biosíntesis , Activación Enzimática , Humanos , Virus de la Influenza A/genética , Virus de la Influenza A/fisiología , Interleucinas/genética , Masculino , Melanoma/genética , Melanoma/metabolismo , Melanoma/patología , Melanoma/terapia , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/terapia , Proteínas Recombinantes/farmacología , Transducción de Señal , Esferoides Celulares , Transgenes , Regulación hacia Arriba
16.
Oncogene ; 30(20): 2333-44, 2011 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-21242963

RESUMEN

Meningiomas are among the most common primary central nervous system tumours in adults. Studies focused on the molecular basis for meningioma development are hampered by a lack of information with regard to the cell of origin for these brain tumours. Herein, we identify a prostaglandin D synthase-positive meningeal precursor as the cell of origin for murine meningioma, and show that neurofibromatosis type 2 (Nf2) inactivation in prostaglandin D2 synthase (PGDS) (+) primordial meningeal cells, before the formation of the three meningeal layers, accounts for the heterogeneity of meningioma histological subtypes. Using a unique PGDSCre strain, we define a critical embryonic and early postnatal developmental window in which biallelic Nf2 inactivation in PGDS (+) progenitor cells results in meningioma formation. Moreover, we identify differentially expressed markers that characterize the two major histological meningioma subtypes both in human and mouse tumours. Collectively, these findings establish the cell of origin for these common brain tumours as well as a susceptible developmental period in which signature genetic mutations culminate in meningioma formation.


Asunto(s)
Linaje de la Célula , Genes de la Neurofibromatosis 2 , Oxidorreductasas Intramoleculares/genética , Lipocalinas/genética , Neoplasias Meníngeas/patología , Meningioma/patología , Animales , Aracnoides/embriología , Aracnoides/metabolismo , Humanos , Ratones , Ratones Transgénicos , Células Madre/metabolismo , Factores de Tiempo
17.
Neuroscience ; 170(1): 178-88, 2010 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-20600672

RESUMEN

The purpose of this study was to investigate the progression of changes in retinal ganglion cells and optic nerve glia in neurofibromatosis-1 (NF1) genetically-engineered mice with optic glioma. Optic glioma tumors were generated in Nf1+/- mice lacking Nf1 expression in GFAP+ cells (astrocytes). Standard immunohistochemistry methods were employed to identify astrocytes (GFAP, S100beta), proliferating progenitor cells (sox2, nestin), microglia (Iba1), endothelial cells (CD31) and retinal ganglion cell (RGC) axons (Neurofilament 68k) in Nf1+/-, Nf1(GFAP)CKO (wild-type mice with Nf1 loss in glial cells), and Nf1+/-(GFAP)CKO (Nf1+/- mice with Nf1 loss in glial cells) mice. Ultrastructural changes in the optic chiasm and nerve were assessed by electron microscopy (EM). RGC were counted in whole retina preparations using high-resolution, mosaic confocal microscopy following their delineation by retrograde FluoroGold labeling. We found that only Nf1+/-(GFAP)CKO mice exhibited gross pre-chiasmatic optic nerve and chiasm enlargements containing aggregated GFAP+/nestin+ and S100beta+/sox2+ cells (neoplastic glia) as well as increased numbers of blood vessels and microglia. Optic gliomas in Nf1+/-(GFAP)CKO mice contained axon fiber irregularities and multilamellar bodies of degenerated myelin. EM and EM tomographic analyses showed increased glial disorganization, disoriented axonal projections, profiles of degenerating myelin and structural alterations at nodes of Ranvier. Lastly, we found reduced RGC numbers in Nf1+/-(GFAP)CKO mice, supporting a model in which the combination of optic nerve Nf1 heterozygosity and glial cell Nf1 loss results in disrupted axonal-glial relationships, subsequently culminating in the degeneration of optic nerve axons and loss of their parent RGC neurons.


Asunto(s)
Modelos Animales de Enfermedad , Neurofibromatosis 1/metabolismo , Glioma del Nervio Óptico/ultraestructura , Nervio Óptico/ultraestructura , Vías Visuales/ultraestructura , Animales , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neurofibromatosis 1/genética , Glioma del Nervio Óptico/genética , Glioma del Nervio Óptico/patología , Células Ganglionares de la Retina/patología , Células Ganglionares de la Retina/ultraestructura , Vías Visuales/patología
18.
Int J Pept Protein Res ; 22(1): 92-109, 1983 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6885253

RESUMEN

Sodium-liquid ammonia reduction has been used for over 50 years for removal of benzyl-type protecting groups in peptide chemistry. Up until now a definitely blue end-point has generally been accepted for detection of the completion of reaction. Systematic investigation with model compounds has revealed that this is not only unnecessary for the complete removal of the protecting groups but also that the application of sodium in excess results in many undesired transformations which can simply be suppressed or even eliminated by optimizing the sodium consumption. Cleavage of tert.-butyloxycarbonyl group and N-C alpha bond, reduction of carboxamide groups to carbinol derivatives, transpeptidation and formation of a hydantoin derivative have been observed in model experiments by using sodium in excess.


Asunto(s)
Péptidos , Amoníaco , Fenómenos Químicos , Química , Oligopéptidos/síntesis química , Oxidación-Reducción , Sodio
19.
J Biol Chem ; 276(40): 37594-601, 2001 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-11483596

RESUMEN

Superoxide and its derivatives are increasingly implicated in the regulation of physiological functions from oxygen sensing and blood pressure regulation to lymphocyte activation and sperm-oocyte fusion. Here we describe a novel superoxide-generating NADPH oxidase referred to as NADPH oxidase 5 (NOX5). NOX5 is distantly related to the gp91(phox) subunit of the phagocyte NADPH oxidase with conserved regions crucial for the electron transport (NADPH, FAD and heme binding sites). However, NOX5 has a unique N-terminal extension that contains three EF hand motifs. The mRNA of NOX5 is expressed in pachytene spermatocytes of testis and in B- and T-lymphocyte-rich areas of spleen and lymph nodes. When heterologously expressed, NOX5 was quiescent in unstimulated cells. However, in response to elevations of the cytosolic Ca(2+) concentration it generated large amounts of superoxide. Upon Ca(2+) activation, NOX5 also displayed a second function: it became a proton channel, presumably to compensate charge and pH alterations due to electron export. In summary, we have identified a novel NADPH oxidase that generates superoxide and functions as a H(+) channel in a Ca(2+)-dependent manner. NOX5 is likely to be involved in Ca(2+)-activated, redox-dependent processes of spermatozoa and lymphocytes such as sperm-oocyte fusion, cell proliferation, and cytokine secretion.


Asunto(s)
Calcio/metabolismo , Ganglios Linfáticos/enzimología , Proteínas de la Membrana/metabolismo , NADPH Oxidasas/metabolismo , Bazo/enzimología , Testículo/enzimología , Secuencia de Aminoácidos , Animales , Células COS , Calcio/fisiología , Citosol/metabolismo , Electrofisiología , Genoma , Células HeLa , Humanos , Hibridación in Situ , Transporte Iónico , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/fisiología , Datos de Secuencia Molecular , NADPH Oxidasa 5 , NADPH Oxidasas/química , NADPH Oxidasas/genética , NADPH Oxidasas/fisiología , Reacción en Cadena de la Polimerasa , Protones , Homología de Secuencia de Aminoácido , Superóxidos/metabolismo
20.
J Cell Sci ; 114(Pt 24): 4587-98, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11792823

RESUMEN

Fibulin-1 is an extracellular matrix protein often associated with fibronectin (FN) in vivo. In this study, the ability of fibulin-1 to modulate adhesion, spreading and motility-promoting activities of FN was investigated. Fibulin-1 was found to have pronounced inhibitory effects on the cell attachment and spreading promoted by FN. Fibulin-1 was also found to inhibit the motility of a variety of cell types on FN substrata. For example, the FN-dependent haptotactic motility of breast carcinoma (MDA MB231) cells, epidermal carcinoma (A431), melanoma (A375 SM), rat pulmonary aortic smooth muscle cells (PAC1) and Chinese hamster ovary (CHO) cells was inhibited by the presence of fibulin-1 bound to FN-coated Boyden chamber membranes. Cells transfected to overproduce fibulin-1 displayed reduced velocity, distance of movement and persistence time on FN substrata. Similarly, the incorporation of fibulin-1 into FN-containing type I collagen gels inhibited the invasion of endocardial cushion mesenchymal cells migrating from cultured embryonic heart explants. By contrast, incorporation of fibulin-1 into collagen gels lacking FN had no effect on the migration of endocardial cushion cells. These results suggest that the motility-suppressive effects of fibulin-1 might be FN specific. Furthermore, such effects are cell-type specific, in that the migration of gingival fibroblasts and endothelial cells on FN substrata is not responsive to fibulin-1. Additional studies found that the mechanism for the motility-suppressive effects of fibulin-1 does not involve perturbations of interactions between alpha5beta1 or alpha4 integrins, or heparan sulfate proteoglycans with FN. However, fibulin-1 was found to inhibit extracellular signal regulated kinase (ERK) activation and to suppress phosphorylation of myosin heavy chain. This ability to influence signal transduction cascades that modulate the actin-myosin motor complex might be the basis for the effects of fibulin-1 on adhesion and motility.


Asunto(s)
Proteínas de Unión al Calcio/fisiología , Movimiento Celular/fisiología , Regulación hacia Abajo , Proteínas de la Matriz Extracelular/fisiología , Fibronectinas/antagonistas & inhibidores , Fibronectinas/fisiología , Actomiosina/metabolismo , Animales , Antígenos CD/fisiología , Células CHO , Bovinos , Adhesión Celular/fisiología , Línea Celular , Inhibición de Migración Celular , Células Cultivadas , Quimiotaxis/fisiología , Embrión de Pollo , Cricetinae , Glicosaminoglicanos/metabolismo , Humanos , Integrina alfa4 , Mesodermo/citología , Mesodermo/fisiología , Ratas , Receptores de Fibronectina/metabolismo , Transducción de Señal/fisiología , Sulfatos/metabolismo , Factores de Tiempo , Células Tumorales Cultivadas
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