title: Different epidermal growth factor growth responses and receptor levels in human colon carcinoma cell lines.
abstract: The growth response to epidermal growth factor (EGF) and the numbers and types of EGF receptors were studied in three human colon tumor cell lines from each of two groups of cell lines that differ markedly in their growth properties and extent of differentiation. Aggressively growing and poorly differentiated colon cells (group I) did not respond to EGF alone, while less aggressively growing and more differentiated cells (group III) responded with increased growth when EGF was added to their chemically defined, serum-free medium. The average number of EGF receptors (EGF-R) measured at the surface of group III cell lines by radioligand binding assays, was eight-fold higher than that measured for group I cell lines. These observations provide evidence for possible autocrine mechanisms that maintain available EGF-R levels in more differentiated group III colon tumor cells and down-regulate EGF-R levels in group I colon tumor cells.
authors.affiliation: Department of Pharmacology, Baylor College of Medicine, Houston, TX 77030.
authors.forename: C W
authors.initials: CW
authors.lastname: Wan
authors.forename: M K
authors.initials: MK
authors.lastname: McKnight
authors.forename: D E
authors.initials: DE
authors.lastname: Brattain
authors.forename: M G
authors.initials: MG
authors.lastname: Brattain
authors.forename: L C
authors.initials: LC
authors.lastname: Yeoman
mesh_terms: D002460:Cell Line; D003110:Colonic Neoplasms / Q000378:metabolism*; D004815:Epidermal Growth Factor / Q000378:metabolism*; D066246:ErbB Receptors / Q000378:metabolism*; D006801:Humans; D007700:Kinetics
chemical_list: D004815:Epidermal Growth Factor; D066246:ErbB Receptors