Dose dependence of the cytokinetic and cytotoxic effects of epirubicin in vitro.
CHO cells were exposed in vitro for 1 h to concentrations of 0.1-20 micrograms/ml of the cytostatic drug epirubicin. Population growth, survival fractions, cell-cycle-phase distribution, and BrdU incorporation were analyzed. A fraction of the cells showed a transitory cytostatic reaction at 1 microgram/ml, and greater than 99% of the cells were killed at 10 micrograms/ml. The survival curve was biphasic with a steep slope at concentrations of up to 5 micrograms/ml. Approximately 0.1% of the cells were resistant to higher concentrations of epirubicin. Bivariate DNA/BrdU flow cytometry revealed that the sensitive cells were blocked and probably killed in the G2M phase of the cell cycle.
Bartkowiak
D
D
Department of Radiotherapy, University of Ulm, Federal of Germany.
Hemmer
J
J
Röttinger
E
E
D000818:Animals; D001973:Bromodeoxyuridine / Q000378:metabolism; D016466:CHO Cells; D002453:Cell Cycle / Q000187:drug effects*; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects*; D006224:Cricetinae; D004247:DNA / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D015251:Epirubicin / Q000494:pharmacology*
D015251:Epirubicin; D004247:DNA; D001973:Bromodeoxyuridine