Various components of the insulin-like growth factor system in tumor tissue, cerebrospinal fluid and peripheral blood of pediatric medulloblastoma and ependymoma patients.
Int J Cancer
; 123(3): 594-600, 2008 Aug 01.
Article
en En
| MEDLINE
| ID: mdl-18478565
The insulin-like growth factor (IGF) system plays an important role in neuronal development and may contribute to the development of brain tumors. In this study, we studied mRNA expression levels of IGFs, insulin-like growth factor binding proteins (IGFBPs) and insulin-like growth factor receptors (IGFRs) in 27 pediatric medulloblastomas, 13 pediatric ependymomas and 5 control cerebella. Compared to normal cerebellum, mRNA levels of IGFBP-2 and IGFBP-3 were significantly increased in medulloblastomas and ependymomas. IGFBP-2 expression was indicative of poor prognosis in medulloblastomas, whereas IGFBP-3 mRNA levels were especially high in anaplastic ependymomas. IGFBP-5 and IGF-II mRNA levels were significantly increased in ependymomas compared to control cerebellum. Protein expression levels of IGFs and IGFBPs were analyzed in the cerebrospinal fluid (CSF) of 16 medulloblastoma, 4 ependymoma and 23 control patients by radioimmuno assay to determine whether they could be used as markers for residual disease after surgery. No aberrant CSF protein expression levels were found for ependymoma patients. In medulloblastoma patients, the IGFBP-3 protein levels were significantly higher than in ependymoma patients and controls. Moreover, enhanced levels of proteolytic fragments of IGFBP-3 were found in the CSF of medulloblastoma patients, being in concordance with a significantly increased IGFBP-3 proteolytic activity in the CSF of these patients. In conclusion, our data suggest that the IGF system is of importance in pediatric medulloblastomas and ependymomas. Larger studies should be conducted to validate the predictive values of the levels of intact IGFBP-3 and proteolytic fragments in CSF in the follow-up of medulloblastomas.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Neoplasias Encefálicas
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Factor I del Crecimiento Similar a la Insulina
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Factor II del Crecimiento Similar a la Insulina
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Proteínas de Unión a Factor de Crecimiento Similar a la Insulina
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Ependimoma
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Meduloblastoma
Tipo de estudio:
Observational_studies
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Prognostic_studies
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Risk_factors_studies
Idioma:
En
Revista:
Int J Cancer
Año:
2008
Tipo del documento:
Article
País de afiliación:
Países Bajos
Pais de publicación:
Estados Unidos