Regulation of p53 expression in HeLa cells.
Incubation of Hela cells in the presence of insulin results in suppression of p53 expression. Treatment of cells with vanadate, an inhibitor of protein tyrosine phosphatase, likewise led to a dramatic reduction in the level of p53 transcript. On the other hand, significant induction of p53 message was demonstrated when Hela cells were exposed to genistein, a protein tyrosine kinase inhibitor. When cells were cultured in the presence of phosphotyrosine, there was a marked decrease in p53 expression. Neither phosphoserine nor phosphothreonine had an effect on p53 expression. Furthermore, simultaneous presence of both insulin and phosphotyrosine did not result in a greater suppression of the p53 message than when either of the agents was acting singly.
Chen
Z P
ZP
Department of Biochemistry, University of Hong Kong, Hong Kong.
Yeung
D C
DC
D004791:Enzyme Inhibitors / Q000494:pharmacology; D019833:Genistein; D006367:HeLa Cells; D006801:Humans; D007328:Insulin / Q000494:pharmacology*; D007529:Isoflavones / Q000494:pharmacology; D009363:Neoplasm Proteins / Q000096:biosynthesis*; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis*; D014638:Vanadates / Q000494:pharmacology
D004791:Enzyme Inhibitors; D007328:Insulin; D007529:Isoflavones; D009363:Neoplasm Proteins; D016159:Tumor Suppressor Protein p53; D014638:Vanadates; D019833:Genistein; D011505:Protein-Tyrosine Kinases