title: Differential mechanisms of multidrug resistance are expressed during stepwise selection of KB-3-1 cells with adriamycin.
abstract: A major limitation of cancer chemotherapy is development of resistance. In this study, we analyzed KB-3-1 cells and adriamycin-selected multidrug resistant sublines KB-A1 and KB-A10 cells for mechanisms of resistance. KB-A10 cells are 10-fold more resistant than KB-A1 cells but have lower P-glycoprotein. Of the known mechanisms of multidrug resistance, topoisomerase II and lung-resistance-related protein were altered between the resistant cell lines. Glutathione-S-transferase activity and multidrug-resistance-related protein levels were higher in the resistant cell lines compared to the sensitive cells but were similar in KB-A1 and KB-A10 cells. Results indicate differential regulation of mechanisms of resistance with stepwise selection.
authors.affiliation: UNIV VERMONT,DEPT PHARMACOL,BURLINGTON,VT 05405. UNIV VERMONT,VERMONT CANC CTR,BURLINGTON,VT 05405. FREE UNIV AMSTERDAM HOSP,DEPT PATHOL,AMSTERDAM,NETHERLANDS.
authors.forename: L
authors.initials: L
authors.lastname: Villagra
authors.forename: A
authors.initials: A
authors.lastname: Darling
authors.forename: D
authors.initials: D
authors.lastname: Yassa
authors.forename: R
authors.initials: R
authors.lastname: Scheper
authors.forename: T
authors.initials: T
authors.lastname: Tritton
authors.forename: A
authors.initials: A
authors.lastname: Bhushan