[The cytotoxic and antimutagenic effect of dithranol]

The anti-psoriatic compound anthralin (dithranol, cignolin) was determined to exhibit a strong cytostatic activity on HeLa-Köln cells; an ED50 concentration of 1.2 microM was determined for the cells. These growth-inhibition data were confirmed by thymidine-uptake experiments. The drug anthralin was determined to be neither direct a mutagen nor a premutagen in the Ames test using Salmonella typhimurium strain TA 100 (anthralin-concentration = 5 microM). Moreover, this compound was a strong inhibitor of benzo(a)pyrene monooxygenase, an enzyme which causes the metabolic conversion of premutagens to mutagens. These data demonstrate anthralin to be an antipsoriatic compound devoid of mutagenic property in vitro with regard to base-pair substitutions and provided at least with some antimutagenic potential.