Valinomycin-induced modulation of adriamycin resistance and cationic probe distribution in MCF-7 cell lines.
In vitro restoration of adriamycin sensitivity in a resistant human breast tumor cell line was obtained by continuous exposure to nanomolar nontoxic valinomycin concentrations. Seven-day treatment with nanomolar valinomycin concentrations caused a slight increase of the signal of the cationic fluorescent cyanine probe DiOC5(3) but did not appreciably affect adriamycin incorporation in the cells. A marked increase of the DiOC5(3) signal was obtained in the presence of micromolar valinomycin concentrations, which were incompatible with the in vitro cellular growth.
Crifò
C
C
Department of Biochemical Sciences, University of Rome La Sapienza, Italy.
Capuozzo
E
E
Cucco
C
C
Zupi
G
G
Salerno
C
C
D002232:Carbocyanines; D002455:Cell Division / Q000187:drug effects; D004317:Doxorubicin / Q000008:administration & dosage / Q000494:pharmacology*; D004351:Drug Resistance; D004357:Drug Synergism; D005456:Fluorescent Dyes; D006801:Humans; D014407:Tumor Cells, Cultured / Q000187:drug effects*; D014634:Valinomycin / Q000008:administration & dosage / Q000494:pharmacology*
D002232:Carbocyanines; D005456:Fluorescent Dyes; D014634:Valinomycin; C015843:3,3'-dipropyloxadicarbocyanine; D004317:Doxorubicin