Overexpression of N-ras oncogene and epidermal growth factor receptor gene in human glioblastomas.
Five human glioblastoma cell lines were analyzed for oncogene activation with a panel of probes. Abnormal expression of the epidermal growth factor receptor (EGFr) gene was detected in four of five lines; N-ras oncogene overexpression was found in all five cell lines. These results were subsequently confirmed with fresh brain tumor and nonneoplastic brain tissue biopsy samples; increased expression of the N-ras proto-oncogene was observed in five of five glioblastomas, all of which also showed EGFr gene overexpression, but not in well-differentiated gliomas or in nonneoplastic brain tissue specimens. No significant differences in Ha-ras and Ki-ras expression were observed. Preliminary histochemical observations showed that intracellular levels of transforming growth factor alpha, a putative biochemical link between these two oncogenes, were significantly higher in glioblastoma cells than in controls.
Gerosa
M A
MA
Department of Neurosurgery, University of Verona, Italy.
Talarico
D
D
Fognani
C
C
Raimondi
E
E
Colombatti
M
M
Tridente
G
G
De Carli
L
L
Della Valle
G
G
D015152:Blotting, Northern; D015139:Blotting, Southern; D001932:Brain Neoplasms / Q000235:genetics*; D002460:Cell Line; D015342:DNA Probes; D066246:ErbB Receptors / Q000235:genetics*; D005910:Glioma / Q000235:genetics*; D006801:Humans; D000090063:Proto-Oncogene Mas; D011519:Proto-Oncogenes
D015342:DNA Probes; C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D066246:ErbB Receptors