Analysis of CIC-associated CpG island methylation in oligoastrocytoma.
Neuropathol Appl Neurobiol
; 39(7): 831-6, 2013 Dec.
Article
em En
| MEDLINE
| ID: mdl-23521081
AIMS: Combined deletion of the whole chromosomal arms 1p and 19q is a frequent event in oligodendroglial tumours. Recent identification of recurrent mutations in CIC on 19q and FUBP1 on 1p and their mutational patterns suggest a loss of function of the respective proteins. Surprisingly, oligoastrocytomas harbouring identical genetic characteristics regarding 1p/19q codeletion and frequent IDH1/2 mutations have been shown to carry CIC mutations in a significantly lower number of cases. The present study investigates whether epigenetic modification may result in silencing of CIC. METHODS: As IDH1/2 mutation-mediated DNA hypermethylation is a prominent feature of these tumours, we analysed a set of CIC wild-type oligoastrocytomas and other diffuse gliomas with regard to 1p/19q status for presence of CIC-associated CpG island methylation by methylation-specific PCR. RESULTS: Both methylation-specific PCR and subsequent bisulphite-sequencing of selected cases revealed an unmethylated status in all samples. CONCLUSION: Despite the hypermethylator phenotype in IDH1/2 mutant tumours and recent detection of gene silencing particularly on retained alleles in oligodendroglial tumours, hypermethylation of CIC-associated CpG islands does not provide an alternative mechanism of functional CIC protein abrogation.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oligodendroglioma
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Cromossomos Humanos Par 1
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Cromossomos Humanos Par 19
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Neoplasias Encefálicas
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Ilhas de CpG
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Metilação de DNA
Tipo de estudo:
Prognostic_studies
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Risk_factors_studies
Limite:
Humans
Idioma:
En
Ano de publicação:
2013
Tipo de documento:
Article