Studies on the kinetics of expression of cell cycle dependent proto-oncogenes during mitogen-induced liver cell proliferation.
The present study was undertaken to determine the kinetics of DNA synthesis and expression of cell cycle dependent proto-oncogenes in response to two types of cell proliferative stimuli in male Wistar rat liver. The peak of DNA synthesis was approximately 24 h after a compensatory cell proliferative stimulus induced by 2/3 partial hepatectomy and approximately 36 h following a mitogenic stimulus obtained with a single dose of lead nitrate (10 micromol/100 g body wt, through femoral vein). Even though both proliferative stimuli induced the expression of c-fos, c-myc and c-Ha-ras, the extent of the increase in c-fos expression was 4- to 5-fold less in mitogen-induced cell proliferation. In addition, while the expression of c-myc, following partial hepatectomy returned to basal level by 4 h, the induced expression of c-myc persisted for up to 40 h during the lead nitrate-induced liver cell proliferation.
Coni
P
P
Department of Pathology, University of Toronto, Ontario, Canada.
Bignone
F A
FA
Pichiri
G
G
Ledda-Columbano
G M
GM
Columbano
A
A
Rao
P M
PM
Rajalakshmi
S
S
Sarma
D S
DS
D000818:Animals; D002453:Cell Cycle; D004247:DNA / Q000096:biosynthesis*; D015870:Gene Expression; D011905:Genes, ras; D007700:Kinetics; D008099:Liver / Q000378:metabolism*; D008297:Male; D009942:Organometallic Compounds / Q000494:pharmacology; D011518:Proto-Oncogene Proteins / Q000235:genetics; D016760:Proto-Oncogene Proteins c-fos; D016271:Proto-Oncogene Proteins c-myc; D011519:Proto-Oncogenes; D051381:Rats; D011919:Rats, Inbred Strains
D009942:Organometallic Compounds; D011518:Proto-Oncogene Proteins; D016760:Proto-Oncogene Proteins c-fos; D016271:Proto-Oncogene Proteins c-myc; D004247:DNA; C008261:lead acetate