Fig. 2.

Antiproliferative and cell death induction activities of PI3K, Akt, and mTORC1 inhibitors in breast cancer cell lines. (A) MDA-MB231 (Left), MCF-7 (Center), and MDA-MB361 (Right) cells were incubated with increasing concentrations of either RAD001, PI-103, ZSTK474, NVP-BEZ235, or C124017 for a period of 72 h. Cells were then fixed and effect on viability plotted as described. The dashed line represents the concentration for which the compound is able to kill 50% of the cells (LD₅₀ values). (B) Raptor protein knock-down was induced in the HCC1954⁽³⁾ cell line by the addition of doxycycline (200 ng/mL) to the growth media. Seventy-two hours later, the cells were analyzed for the effects on proliferation (Right) and signaling events (Left), either in absence or presence of the indicated amounts of the PI3K inhibitor ZSTK474.