title: Disulfiram is a potent in vitro inhibitor of DNA topoisomerases.
abstract: The drug disulfiram is a thiol-reacting drug that is relatively nontoxic when used alone and has been used in the therapy of alcohol abuse for more than 40 years. Several effects of this drug have been reported for DNA synthesis and cell proliferation. In this study, the inhibitory effect of disulfiram on topoisomerase I and II activity was investigated by measuring the relaxation of superhelical plasmid pBR322 DNA. Disulfiram (1-100 microM) inhibited topoisomerase I and II in a concentration-dependent manner (IC(50) congruent with 42 +/- 8 and 30 +/- 9 microM, respectively). Consistent with the assumption that a thiol residue is involved, dithiothreitol (1 mM) markedly prevented the inhibitory effect of disulfiram on the activity of both classes of topoisomerases. These findings might explain certain aspects of disulfiram toxicity and encourage new studies to determine the usefulness of this drug and its analogues as antineoplastic agent.
authors.affiliation: Applied Biochemistry, Clinical Research Center, Karolinska Institute, Novum, Huddinge University Hospital, S-141 86 Huddinge, Sweden. Sebastian.Yakisich@neuro.hs.sll.se
authors.forename: J S
authors.initials: JS
authors.lastname: Yakisich
authors.forename: A
authors.initials: A
authors.lastname: Sidén
authors.forename: P
authors.initials: P
authors.lastname: Eneroth
authors.forename: M
authors.initials: M
authors.lastname: Cruz
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology; D002455:Cell Division; D004247:DNA / Q000378:metabolism; D004264:DNA Topoisomerases, Type I / Q000378:metabolism; D004250:DNA Topoisomerases, Type II / Q000378:metabolism; D004221:Disulfiram / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004587:Electrophoresis, Agar Gel; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D020128:Inhibitory Concentration 50; D010957:Plasmids / Q000378:metabolism; D059004:Topoisomerase I Inhibitors
chemical_list: D000970:Antineoplastic Agents; D004791:Enzyme Inhibitors; D059004:Topoisomerase I Inhibitors; D004247:DNA; D004264:DNA Topoisomerases, Type I; D004250:DNA Topoisomerases, Type II; D004221:Disulfiram