Open AccessDifferential responsiveness of myc- and ras-transfected cells to growth factors: selective stimulation of myc-transfected cells by epidermal growth factor.
Author(s) -
David F. Stern,
Anita B. Roberts,
Nanette S. Roche,
Michael B. Sporn,
Robert A. Weinberg
Publication year - 1986
Publication title -
molecular and cellular biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.14
H-Index - 327
eISSN - 1067-8824
pISSN - 0270-7306
DOI - 10.1128/mcb.6.3.870
Subject(s) - biology , transfection , epidermal growth factor , autocrine signalling , growth factor , platelet derived growth factor receptor , platelet derived growth factor , transforming growth factor , transforming growth factor beta , 3t3 cells , growth factor receptor inhibitor , microbiology and biotechnology , transforming growth factor, beta 3 , stimulation , tgf alpha , cell culture , endocrinology , receptor , biochemistry , genetics
To identify functional relationships between oncogenes and growth factors, we compared the effects of transfected myc and ras oncogenes on the responsiveness of Fischer rat 3T3 cells to three growth factors: epidermal growth factor (EGF), platelet-derived growth factor (PDGF), and transforming growth factor-beta (TGF-beta). Control cells did not grow in soft agar under any conditions. ras-Transfected cells grew in soft agar under all conditions tested and were insensitive to the stimulatory effects of exogenous growth factors. These cells secreted elevated levels of both EGF-like factors and TGF-beta, suggesting that the lack of responsiveness of these cells to exogenous growth factors arose from autocrine stimulation. myc-Transfected cells displayed conditional anchorage-independent growth: they formed numerous colonies in soft agar in the presence of EGF but relatively few colonies in the presence of PDGF or TGF-beta. Secretion of EGF-like factors and TGF-beta by these cells was not elevated above that of control cells. These results suggest a model for the mechanism of cooperation between myc and ras oncogenes in which ras-like genes induce growth factor production, while myc-like genes increase the responsiveness of cells to these factors.