Daunorubicin (DNR) and 1-β-D-arabinofuranosylcytosine (Ara-C) act in a schedule-dependent fashion on leukemic cells. The present study was undertaken to determine whether the inhibition exerted by DNR on Ara-C cytotoxicity on HL 60 cells could be accounted for by an impairment of its uptake. After 250 ng/ml DNR treatment for 30 min, the time course of Ara-C uptake was measured, up to 128 min of incubation at 37°C and at 4°C, compared with controls. We found that DNR inhibits Ara-C uptake both at 37 and 4°C, mostly acting on passive diffusion.
- Scheduling-dependent effect Antitumor drugs
ASJC Scopus subject areas
- Pharmacology (medical)