Modulation of c-myc gene expression by extracellular stimuli in rat hepatoma cells.
Modulation of c-myc gene expression by extracellular stimuli in H4IIE rat hepatoma cells was investigated by Northern blot analysis. Treatment of these cells with phorbol 12-O-tetradecanoate 13-acetate (TPA), insulin and concanavalin A (Con A) resulted in transient accumulation of c-myc transcripts within 2 hours. The induction of c-myc mRNA was dose dependent with similar responses for all three agents. The maximally induced c-myc mRNA levels varied from 5- to 15-fold of the control. Treatment with cycloheximide (10 micrograms/ml) and H7, a protein kinase C inhibitor (20 microM), inhibited this induction, suggesting that c-myc induction by these agents requires protein synthesis and protein kinase C activation.
Department of Toxicology and Microbial Chemistry, Faculty of Pharmaceutical Sciences, Science University of Tokyo, Japan.
S
S
Morimura
K
K
Kato
F
F
Tashiro
Y
Y
Ueno
D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D000818:Animals; D015152:Blotting, Northern; D003208:Concanavalin A / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D003513:Cycloheximide / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D015870:Gene Expression / Q000187:drug effects*; D007328:Insulin / Q000494:pharmacology*; D007329:Insulin Antagonists / Q000494:pharmacology; D007546:Isoquinolines / Q000494:pharmacology; D008114:Liver Neoplasms, Experimental; D010879:Piperazines / Q000494:pharmacology; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis / Q000235:genetics*; D016271:Proto-Oncogene Proteins c-myc; D011519:Proto-Oncogenes; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D015398:Signal Transduction; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
D007328:Insulin; D007329:Insulin Antagonists; D007546:Isoquinolines; D010879:Piperazines; D011518:Proto-Oncogene Proteins; D016271:Proto-Oncogene Proteins c-myc; D012333:RNA, Messenger; D003208:Concanavalin A; D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D003513:Cycloheximide; D013755:Tetradecanoylphorbol Acetate