Expression of epidermal growth factor receptor and associated glycoprotein on cultured human brain tumor cells

✍ Scribed by Peter A. Steck; Gary E. Gallick; Steve A. Maxwell; Richard P. Moser; Jordan U. Gutterman; W. K. Alfred Yung; William S. Kloetzer; Ralph B. Arlinghaus

• Publisher: John Wiley and Sons
• Year: 1986
• Tongue: English
• Weight: 638 KB
• Volume: 32
• Category: Article
• ISSN: 0730-2312
• DOI: 10.1002/jcb.240320102

✦ Synopsis

The expression of epidermal growth factor (EGF-R) in normal glial and glioma cells grown in culture was examined by using several independent assays. Immunoprecipitation with the monoclonal antibody R1 of extracts from metabolically labeled glial and glioma cells revealed a protein of M, -170,000, with a migration in sodium dodecyl sulfate-polyacrylamide gels identical to the EGR-R of A431 epidermal carcinoma cells. Furthermore, in the majority of glioma extracts, a protein of M, -190,000 was specifically immunoprecipitated by this antibody.

Similar results were obtained by immunoblotting with a second antibody directed against a synthetic peptide in the sequence of the v-erbB oncogene. In cell lines expressing both proteins, each was specifically phosphorylated on tyrosine in immune complex kinase assays. The majority of glioma cells bound between 40,000 to 80,000 1251-labeled epidermal growth factor molecules per cell. These results suggest that the expression of EGF-R is common in cultured human glioma cells. In addition, a structurally related protein, is expressed in some of these cells.