Interferon-enhancement of tyrosine phosphorylation of epidermal growth factor receptors in human breast carcinoma cells.
Interferons have been postulated to inhibit cell growth by modulating the cellular response to growth factors. We now demonstrate that interferon increases tyrosine phosphorylation of EGFR in the human breast carcinoma cell line MDA 468, in the presence of EGF. The kinase activity of EGFR was elevated about two-fold when cells were cultured in the presence of IFN. Antiphosphotyrosine immunoblotting revealed that phosphorylation was increased two-fold on tyrosine residues in EGFR. These results suggest that IFN affects EGF signal transduction, and that such changes may play a role in growth inhibition induced by IFN in MDA 468 cells.
Huslig
R L
RL
University of Maryland Cancer Center, Program of Oncology/Department of Pathology, Baltimore 21201.
Mishra
S
S
Hamburger
A W
AW
D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D002277:Carcinoma / Q000378:metabolism* / Q000473:pathology; D002455:Cell Division / Q000187:drug effects; D004357:Drug Synergism; D066246:ErbB Receptors / Q000378:metabolism*; D005260:Female; D019833:Genistein; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology*; D007529:Isoflavones / Q000494:pharmacology; D010766:Phosphorylation / Q000187:drug effects; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D014407:Tumor Cells, Cultured; D014443:Tyrosine / Q000494:pharmacology*
D007529:Isoflavones; D014443:Tyrosine; D007371:Interferon-gamma; D019833:Genistein; D066246:ErbB Receptors; D011505:Protein-Tyrosine Kinases