Figure 7. Ectopic MDM2 expression abrogates enhanced effect of combined rapamycin/doxorubicin therapy.

(A–B) U2-OS cells were transiently transfected with MDM2 or a vector control. Twenty-four hours post transfections, cells were pretreated with rapamycin (100 nM) for 48 hours and then treated with doxorubicin (1 µg/mL) for 36 hours. Both floating and adherent cells were collected, and subjected to western blotting (A) or flow cytometry analysis (B). (C) Morphology of U2-OS cells was recorded by phase contrast microscopy (100×).