Methylation Status of the O6-Methylguanine- Deoxyribonucleic Acid Methyltransferase Gene Promoter in World Health Organization Grade III Gliomas
Journal of Korean Neurosurgical Society
; : 385-388, 2009.
Article
in En
| WPRIM
| ID: wpr-153155
Responsible library:
WPRO
ABSTRACT
OBJECTIVE: We analyzed the methylation status of the O6-methylguanine-DNA methyltransferase (MGMT) gene promoter in World Health Organization (WHO) grade III gliomas in association with other molecular markers to evaluate their prevalence. METHODS: The samples of a total of 36 newly WHO grade III glioma patients including 19 anaplastic oligodendrogliomas (AO), 7 anaplastic oligoastrocytomas (AOA), and 10 anaplastic astrocytomas (AA) were analyzed. The methylation status of the MGMT gene promoter was confirmed by methylation-specific polymerase chain reaction. The 1p/19q chromosomal deletion status and EGFR amplification were assessed by Fluorescence In-Situ Hybridization. MGMT, EGFR, EGFRvIII, and p53 expression were analyzed by immunohistochemical staining. RESULTS: The MGMT gene promoter was methylated in 32 (88.9%) and unmethylated in 4 (11.2%). Among them, all of the AO and AOA had methylated MGMT gene promoter without exception. Significant associations between MGMT gene promoter hypermethylation and 1p/19q deletion was observed (p = 0.003). Other molecular markers failed to show significant associations between MGMT gene promoter statuses. CONCLUSION: There was extensive epigenetic silencing of MGMT gene in high grade gliomas with oligodendroglial component. Together with frequent 1p/19q co-deletion in oligodendroglial tumors, this may add plausible explanations supporting the relative favorable prognosis in oligodendroglial tumors compared with pure astrocytic tumors.
Key words
Full text:
1
Index:
WPRIM
Main subject:
Oligodendroglioma
/
Prognosis
/
Astrocytoma
/
World Health Organization
/
DNA
/
Chimera
/
Polymerase Chain Reaction
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Global Health
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Prevalence
/
Epigenomics
Type of study:
Prevalence_studies
/
Prognostic_studies
Limits:
Humans
Language:
En
Journal:
Journal of Korean Neurosurgical Society
Year:
2009
Type:
Article