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2.
Clin Transl Radiat Oncol ; 13: 44-49, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30345398

RESUMEN

INTRODUCTION: Prospective clinical trials are essential to translate new therapy concepts or rather any scientific development into the medical routine. Besides a sophisticated trial protocol, the success of clinical trials depends on patient recruitment and participation. Patient recruitment remains a challenge and depends on several factors. To get a current picture of the patients' attitude, we conducted the present survey. METHODS: We designed a survey with seven questions, which was given to all oncological patients treated within a timeframe of three months between Mai and July 2017. Participation was voluntary and anonymous. The questionnaire mainly inquires patients' participation in clinical trials in a university-based setting, their attitude towards clinical trials regarding risks and benefits, and their source of information in this context. RESULTS: 771 patients (1:1 male/female) participated with a median age of 61 years (range 18-91 years) with a response rate of 71.5%. Of all, 17.8% (137/771) were participating in a clinical trial. The most mentioned reason was to serve medical progress and cancer research. Out of the patients not currently participating in a trial, 79 (12.7%, 79/623) refusers named the following main reasons: extensive travel time to the clinic, no therapeutic advantage, and too time-consuming. Out of the patients not offered to take part in a trial, 265 (51.0%, 265/520) would participate if offered. Of all patients, 8.3% (64/771) used the clinics' homepage as a source of information, of those 79.7% (51/64) were satisfied with its content. To enhance patient recruitment strategies, we asked how patients wish to be informed about possible trials: More than half (52.0%) of the questioned patients preferred an individual medical consultation with their physician.We further analyzed the trial participation depending on age, gender, unit, and tumor entity. We could show a significant influence of age (p < 0.001) but not for gender (p = 0.724). The trial participation was also significantly associated with the treating unit (p < 0.001) and tumor entity (p = 0.001). CONCLUSION: Patients are willing to participate in clinical trials. Better information strategies need to be implemented. Physicians need to be aware of running trials within their department and must counseling counsel patients effectively to improve recruitment. Trial concepts should keep in mind patients' needs including an adequate number of appointments, positive risk-benefit profiles, and information material.

3.
J Biol Chem ; 278(32): 30028-36, 2003 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-12748172

RESUMEN

Anaplastic large-cell lymphoma is a subtype of non-Hodgkin lymphomas characterized by the expression of CD30. More than half of these lymphomas carry a chromosomal translocation t(2;5) leading to expression of the oncogenic tyrosine kinase nucleophosmin-anaplastic lymphoma kinase (NPM-ALK). NPM-ALK is capable of transforming fibroblasts and lymphocytes in vitro and of causing lymphomas in mice. Previously, we and others demonstrated phospholipase C-gamma and phosphatidylinositol 3-kinase as crucial downstream signaling mediators of NPM-ALK-induced oncogenicity. In this study, we used an ALK fusion protein as bait in a yeast two-hybrid screen identifying NIPA (nuclear interacting partner of ALK) as a novel downstream target of NPM-ALK. NIPA encodes a 60-kDa protein that is expressed in a broad range of human tissues and contains a classical nuclear translocation signal in its C terminus, which directs its nuclear localization. NIPA interacts with NPM-ALK and other ALK fusions in a tyrosine kinase-dependent manner and is phosphorylated in NPM-ALK-expressing cells on tyrosine and serine residues with serine 354 as a major phosphorylation site. Overexpression of NIPA in Ba/F3 cells was able to protect from apoptosis induced by IL-3 withdrawal. Mutations of the nuclear translocation signal or the Ser-354 phosphorylation site impaired the antiapoptotic function of NIPA. In NPM-ALK-transformed Ba/F3 cells, apoptosis triggered by wortmannin treatment was enhanced by overexpression of putative dominant-negative NIPA mutants. These results implicate an antiapoptotic role for NIPA in NPM-ALK-mediated signaling events.


Asunto(s)
Núcleo Celular/metabolismo , Linfoma de Células B Grandes Difuso/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Fosfolipasas de Tipo C/química , Transporte Activo de Núcleo Celular , Proteínas Adaptadoras Transductoras de Señales , Secuencia de Aminoácidos , Androstadienos/farmacología , Animales , Apoptosis , Northern Blotting , Células COS , Ciclo Celular , Proteínas de Ciclo Celular , Línea Celular , Clonación Molecular , ADN Complementario/metabolismo , Electroforesis en Gel de Poliacrilamida , Inhibidores Enzimáticos/farmacología , Fibroblastos/metabolismo , Glutatión Transferasa/metabolismo , Humanos , Immunoblotting , Etiquetado Corte-Fin in Situ , Antígeno Ki-1/biosíntesis , Ratones , Microscopía Fluorescente , Modelos Biológicos , Datos de Secuencia Molecular , Mutación , Ácidos Fosfoaminos/metabolismo , Fosfolipasa C gamma , Fosforilación , Plásmidos/metabolismo , Unión Proteica , Estructura Terciaria de Proteína , Proteínas Tirosina Quinasas/química , ARN Mensajero/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Homología de Secuencia de Aminoácido , Serina/química , Transducción de Señal , Factores de Tiempo , Distribución Tisular , Transfección , Técnicas del Sistema de Dos Híbridos , Tirosina/química , Wortmanina
4.
J Biol Chem ; 277(14): 12437-45, 2002 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-11790798

RESUMEN

Vav is a guanine nucleotide exchange factor for the Rho/Rac family predominantly expressed in hematopoietic cells and implicated in cell proliferation and cytoskeletal organization. The oncogenic tyrosine kinase Bcr-Abl has been shown to activate Rac-1, which is important for Bcr-Abl induced leukemogenesis. Previous studies by Matsuguchi et al. (Matsuguchi, T., Inhorn, R. C., Carlesso, N., Xu, G., Druker, B., and Griffin, J. D. (1995) EMBO J. 14, 257-265) describe enhanced phosphorylation of Vav in Bcr-Abl-expressing Mo7e cells yet fail to demonstrate association of the two proteins. Here, we report the identification of a direct complex between Vav and Bcr-Abl in yeast, in vitro and in vivo. Furthermore, we show tyrosine phosphorylation of Vav by Bcr-Abl. Mutational analysis revealed that the SH2 domain and the C-terminal SH3 domain as well as a tetraproline motif directly adjacent to the N-terminal SH3 domain of Vav are important for establishing this phosphotyrosine dependent interaction. Activation of Rac-1 by Bcr-Abl was abrogated by co-expression of the Vav C terminus encoding the SH3-SH2-SH3 domains as a dominant negative construct. Bcr-Abl transduced primary bone marrow from Vav knock-out mice showed reduced proliferation in a culture cell transformation assay compared with wild-type bone marrow. These results suggest, that Bcr-Abl utilizes Vav as a guanine nucleotide exchange factor to activate Rac-1 in a process that involves a folding mechanism of the Vav C terminus. Given the importance of Rac-1 activation for Bcr-Abl-mediated leukemogenesis, this mechanism may be crucial for the molecular pathogenesis of chronic myeloid leukemia and of importance for other signal transduction pathways leading to the activation of Rac-1.


Asunto(s)
Proteínas de Ciclo Celular , Proteínas de Fusión bcr-abl/química , Proteínas de Fusión bcr-abl/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteína de Unión al GTP rac1/metabolismo , Células 3T3 , Animales , Células de la Médula Ósea/metabolismo , Línea Celular , ADN Complementario/metabolismo , Electroforesis en Gel de Poliacrilamida , Activación Enzimática , Genes Dominantes , Glutatión Transferasa/metabolismo , Humanos , Immunoblotting , Ratones , Ratones Noqueados , Fosforilación , Plásmidos/metabolismo , Pruebas de Precipitina , Prolina/química , Unión Proteica , Estructura Terciaria de Proteína , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas c-vav , Proteínas Recombinantes de Fusión/metabolismo , Retroviridae/genética , Transducción de Señal , Temperatura , Transfección , Técnicas del Sistema de Dos Híbridos , Tirosina/metabolismo , Dominios Homologos src
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