Molecular genetic changes in a series of neuroepithelial tumors of childhood.
Amplification of the EGFR, mdm2, CDK4 and PDGFR A genes has been widely demonstrated in adult malignant gliomas, almost exclusively glioblastomas. To determine the role of these mutational events in pediatric astrocytic gliomas we investigated the presence of EGFR, mdm2, CDK4 and PDGFR A gene amplification in 38 childhood brain tumor biopsies, including 24 low-grade astrocytomas and 14 malignant tumors. We used differential PCR assay on DNA extracted either from paraffin embedded or frozen tissues. EGFR gene amplification was detected in 4 out of 14 malignant tumors; no low-grade astrocytoma showed amplification. Tumors with EGFR gene amplification were negative for the presence of p53 mutations, as observed in a previous study. One glioblastoma showed PDGFR A amplification, while no amplifications were observed for mdm2 and CDK4 genes. These data are in line with those obtained from studies on gliomas of adults and suggest the existence of two different subsets of malignant gliomas also in pediatric brain tumors: one carrying EGFR gene amplification, the other showing p53 mutations.
Di Sapio
Alessia
A
Divisione Universitaria di Neurologia, Ospedale San Luigi, Torino, Italy. alessia.disapio@tin.it
Morra
Isabella
I
Pradotto
Luca
L
Guido
Marilena
M
Schiffer
Davide
D
Mauro
Alessandro
A
D000293:Adolescent; D001254:Astrocytoma / Q000235:genetics*; D001932:Brain Neoplasms / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D051358:Cyclin-Dependent Kinase 4; D018844:Cyclin-Dependent Kinases / Q000235:genetics; D004252:DNA Mutational Analysis; D004273:DNA, Neoplasm / Q000032:analysis; D005784:Gene Amplification; D018773:Genes, erbB-1 / Q000235:genetics; D016158:Genes, p53 / Q000235:genetics; D006801:Humans; D007223:Infant; D009687:Nuclear Proteins; D016133:Polymerase Chain Reaction; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D051736:Proto-Oncogene Proteins c-mdm2; D017479:Receptors, Platelet-Derived Growth Factor / Q000235:genetics
D004273:DNA, Neoplasm; D009687:Nuclear Proteins; D011518:Proto-Oncogene Proteins; C497206:MDM2 protein, human; D051736:Proto-Oncogene Proteins c-mdm2; D017479:Receptors, Platelet-Derived Growth Factor; C495900:CDK4 protein, human; D051358:Cyclin-Dependent Kinase 4; D018844:Cyclin-Dependent Kinases