Analysis of EGFR overexpression, EGFR gene amplification and the EGFRvIII mutation in Portuguese high-grade gliomas.
BACKGROUND
Patients with malignant gliomas do not respond to any current therapy. Epidermal growth factor receptor (EGFR) controls several oncogenic processes, being frequently up-regulated in gliomas due to overexpression, gene amplification and gene mutation. EGFR inhibitors are being tried in gliomas, yet the molecular determinants of therapeutic response are unclear.


METHODS
EGFR overexpression, EGFRvIII mutation and EGFR amplification were determined by immunohistochemistry and chromogenic in situ hybridization (CISH) in 27 primary glioblastomas (GBM), 24 anaplastic oligodendrogliomas (AO) and four anaplastic oligoastrocytomas (AOA).


RESULTS
EGFR overexpression was associated with EGFR amplification, being found in 48% and 53% GBM, 33% and 40% AO and 75% and 67% AOA, respectively. EGFRvIII was found in 22% GBM, 8% AO and was absent in AOA. No association was observed between EGFR alterations and patient survival.


CONCLUSIONS
We characterized, for the first time, EGFR molecular alterations in Portuguese patients with malignant glioma and identified a subpopulation of patients presenting putative biomarkers for EGFR-based therapies.
Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal.
Marta
M
Viana-Pereira
José Manuel
JM
Lopes
Suzie
S
Little
Fernanda
F
Milanezi
Diana
D
Basto
Fernando
F
Pardal
Chris
C
Jones
Rui Manuel
RM
Reis
D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000378:metabolism*; D066246:ErbB Receptors / Q000235:genetics*; D005260:Female; D005784:Gene Amplification; D005909:Glioblastoma / Q000235:genetics; D005910:Glioma / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D009837:Oligodendroglioma / Q000235:genetics; D011174:Portugal; D011379:Prognosis; D015854:Up-Regulation
C410723:epidermal growth factor receptor VIII; D066246:ErbB Receptors