Figure 3.

Effect of ZD6474 on the uptake of rhodamine-123 (Rho-123) in MCF-7/ADR cells. (A) MCF-7/ADR cells were incubated with 5 μM rhodamine-123 in the absence (a) or presence of 10 μM ZD6474 (b) at 37°C for 1 h. The cells were observed and photographed under a fluorescence microscope. (B) Uptake of rhodamine-123 in multidrug-resistant MCF-7/ADR cells was analysed by flow cytometry. (C) ZD6474 had no evident effect on the rhodamine-123 uptake in MCF-7 cells that do not overexpress P-gp. Data shown are representatives of at least three independent experiments.