title: Superiority of adriamycin-14-octanoate over adriamycin in reducing viability of methotrexate-resistant L5178Y cells: brief communication.
abstract: Adriamycin-14-octanoate (ADR-OCT) was superior to adriamycin (ADR) in reducing the viability of L5178Y cells resistant to methotrexate (MTX). This effect was seen in logarithmically growing and plateau-phase cultures and increased both with dose and duration of exposure. Both ADR-OCT and ADR were effective inhibitors of the exogenous Escherichia coli DNA-dependent RNA polymerases in vitro and of the endogenous polymerase in mammalian cultured cells. Drug concentrations required for approximately 50% enzyme inhibition in both systems were comparable for both agents, being of the order of 10(-5) M. These experimental studies suggested that ADR-OCT may be a valuable agent for treating neoplasms resistant to MTX.
mesh_terms: D000818:Animals; D002455:Cell Division; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D012321:DNA-Directed RNA Polymerases / Q000037:antagonists & inhibitors; D004317:Doxorubicin / Q000031:analogs & derivatives* / Q000494:pharmacology*; D004351:Drug Resistance; D066298:In Vitro Techniques; D007942:Leukemia, Experimental / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D008727:Methotrexate / Q000494:pharmacology*
chemical_list: D004317:Doxorubicin; D012321:DNA-Directed RNA Polymerases; D008727:Methotrexate