Targeted therapy for BRAFV600E malignant astrocytoma.
Clin Cancer Res
; 17(24): 7595-604, 2011 Dec 15.
Article
en En
| MEDLINE
| ID: mdl-22038996
ABSTRACT
PURPOSE:
Malignant astrocytomas (MA) are aggressive central nervous system tumors with poor prognosis. Activating mutation of BRAF (BRAF(V600E)) has been reported in a subset of these tumors, especially in children. We have investigated the incidence of BRAF(V600E) in additional pediatric patient cohorts and examined the effects of BRAF blockade in preclinical models of BRAF(V600E) and wild-type BRAF MA. EXPERIMENTALDESIGN:
BRAF(V600E) mutation status was examined in two pediatric MA patient cohorts. For functional studies, BRAF(V600E) MA cell lines were used to investigate the effects of BRAF shRNA knockdown in vitro, and to investigate BRAF pharmacologic inhibition in vitro and in vivo.RESULTS:
BRAF(V600E) mutations were identified in 11 and 10% of MAs from two distinct series of tumors (six of 58 cases total). BRAF was expressed in all MA cell lines examined, among which BRAF(V600E) was identified in four instances. Using the BRAF(V600E)-specific inhibitor PLX4720, pharmacologic blockade of BRAF revealed preferential antiproliferative activity against BRAF(V600E) mutant cells in vitro, in contrast to the use of shRNA-mediated knockdown of BRAF, which inhibited cell growth of glioma cell lines regardless of BRAF mutation status. Using orthotopic MA xenografts, we show that PLX4720 treatment decreases tumor growth and increases overall survival in mice-bearing BRAF(V600E) mutant xenografts, while being ineffective, and possibly tumor promoting, against xenografts with wild-type BRAF.CONCLUSIONS:
Our results indicate a 10% incidence of activating BRAF(V600E) among pediatric MAs. With regard to implications for therapy, our results support evaluation of BRAF(V600E)-specific inhibitors for treating BRAF(V600E) MA patients.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Astrocitoma
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Neoplasias Encefálicas
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Proteínas Proto-Oncogénicas B-raf
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Mutación
Límite:
Adolescent
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Adult
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Animals
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Child
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Child, preschool
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Female
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Humans
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Infant
Idioma:
En
Revista:
Clin Cancer Res
Asunto de la revista:
NEOPLASIAS
Año:
2011
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
EEUU
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ESTADOS UNIDOS
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ESTADOS UNIDOS DA AMERICA
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EUA
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UNITED STATES
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UNITED STATES OF AMERICA
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US
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USA