Regulation of c-fos expression in primary culture of guinea pig glandular epithelial cells stimulated by growth factors and estradiol.
The c-fos expression was investigated in primary culture of guinea pig glandular epithelial cells. These cells were made quiescent by serum deprivation and stimulated with fetal calf serum (FCS, 15%), 17 beta-estradiol (E2 10(-8) mol/l) alone or in combination with epidermal growth factor (EGF, 100 ng/ml) and insulin (I, 10 micrograms/ml). Low levels of c-fos mRNA were detectable in quiescent cells and were not increased in cells stimulated with either E2, EGF, I, or EGF plus I. On the contrary, the c-fos mRNA were early and transiently increased by FCS or E2 plus EGF plus I (4.5 and 9.5 fold induction, respectively). This effect was independent of de novo protein synthesis since it was not abolished in the presence of cycloheximide. It appears that E2 acts in a multiple step process including the stimulation by EGF plus insulin.
Jouvenot
M
M
INSERM U 198, Biochimie Hormonale et des Régulations, Besançon, France.
Pellerin
I
I
Maréchal
G
G
Royez
M
M
Ordener
C
C
Alkhalaf
M
M
Adessi
G L
GL
D000818:Animals; D001769:Blood; D002478:Cells, Cultured; D004717:Endometrium / Q000187:drug effects / Q000378:metabolism*; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D004848:Epithelium / Q000378:metabolism; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects*; D006168:Guinea Pigs; D007328:Insulin / Q000494:pharmacology*; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger / Q000378:metabolism
D007328:Insulin; D011518:Proto-Oncogene Proteins; D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger; D004958:Estradiol; D004815:Epidermal Growth Factor