title: Retinoic acid blockade of imidazole-induced tyrosinase expression in B16 melanoma cultures: similar effects of the active retinoid and triiodothyronine.
abstract: The effect of retinoic acid on the induction of tyrosinase (EC 1:14.18.1) by imidazole was determined in cultured B16/C3 melanoma cells. Retinoic acid could block the induction of enzyme activity within 3 hours of addition to the culture medium at a physiological concentration (10nM). The blockade was similar to that of 3,3',5-L-triiodothyronine (T3) already reported. mRNA hybridizable to a tyrosinase DNA probe was induced by imidazole while retinoic acid and T3 blocked that increase. These observations suggest that retinoic acid can mimic the action of T3 in B16 melanoma cells in culture.
authors.affiliation: Department of Medicine, State University of New York, Buffalo 14215.
authors.forename: T J
authors.initials: TJ
authors.lastname: Smith
authors.forename: J T
authors.initials: JT
authors.lastname: Warren
authors.forename: E L
authors.initials: EL
authors.lastname: Kline
mesh_terms: D000818:Animals; D004156:Catechol Oxidase / Q000037:antagonists & inhibitors*; D002460:Cell Line; D004790:Enzyme Induction / Q000187:drug effects; D007093:Imidazoles / Q000494:pharmacology*; D008545:Melanoma / Q000201:enzymology*; D051379:Mice; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis; D014212:Tretinoin / Q000494:pharmacology*; D014284:Triiodothyronine / Q000494:pharmacology*; D014407:Tumor Cells, Cultured / Q000201:enzymology
chemical_list: D007093:Imidazoles; D012333:RNA, Messenger; D014284:Triiodothyronine; D014212:Tretinoin; C029899:imidazole; D004156:Catechol Oxidase; D014442:Monophenol Monooxygenase