Figure 7.

Flow cytometric analysis of the effect of pinoresinol (14) on the efflux of doxorubicin (DOX) from (A) Lucena 1 and (B) K562 cells. After 1 h pre-incubation with 14 at 112 μM, verapamil or ethanol, cells were exposed to DOX for 1 h. Subsequently, cells were washed and then incubated in the presence of 14 at 112 μM, verapamil or ethanol at various time points in a DOX-free medium. Data points represent the mean ± SE. Significant differences from the control were determined by using unpaired one-tailed Student's t-test (^**p < 0.01, ^*p < 0.05).