Proto-oncogene abnormalities and their relationship to tumorigenicity in some human glioblastomas.
Human glioblastomas are highly malignant intracranial tumors, some of which demonstrate amplification of the epidermal growth factor-receptor (EGF-R) gene. Overexpression of this gene is seen in the majority of primary tumors; however, the role of the EGF-R gene in glial tumorigenesis is unknown. The authors explored the relationship between EGF-R gene expression and glioblastoma cell growth in vitro and in vivo and found that this level of EGF-R gene expression did not correlate with tumor cell growth either in soft agar or in the nude mouse. This suggests that the EGF-R gene is not involved in effecting direct growth stimulation in glial oncogenesis. Tumorigenesis involves differentiation arrest; therefore, the expression of several proto-oncogenes in neuroectodermal tumors was investigated to evaluate the potential involvement of the EGF-R gene in glial differentiation. A nonoverlapping expression of the N-myc and EGF-R genes was found in neuronal-derived and glial-derived tumors, respectively. This suggests that the EGF-R gene may be involved in differentiation or its arrest in glia.
U
H S
HS
Division of Neurological Surgery, University of California, San Diego.
Kelley
P Y
PY
Hatton
J D
JD
Shew
J Y
JY
D000818:Animals; D002455:Cell Division; D002869:Chromosome Aberrations / Q000150:complications*; D025063:Chromosome Disorders; D066246:ErbB Receptors / Q000235:genetics; D005134:Eye Neoplasms / Q000235:genetics; D005784:Gene Amplification; D005910:Glioma / Q000209:etiology* / Q000235:genetics / Q000473:pathology; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D009447:Neuroblastoma / Q000235:genetics; D000090063:Proto-Oncogene Mas; D011519:Proto-Oncogenes; D012175:Retinoblastoma / Q000235:genetics; D014407:Tumor Cells, Cultured
C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D066246:ErbB Receptors