Figure 6. Effect of cryptopleurin on the TNF-α-induced apoptosis.

(A) MDA-MB231 cells were pretreated with 30 nM cryptopleurine for 12 h and then incubated with 20 ng/ml TNF-α for 24 h, and subsequently stained with Annexin V-FITC and propidium iodide, followed by analysis using a flow cytometer. Representative plots of one set of triplicate experiments. Early apoptotic cell (Annexin-V⁺ and PI) were displayed in the lower right quadrant and late apoptotic cells (Annexin-V⁺ and PI⁺) were shown in the upper right quadrant. (B) MDA-MB231 cells were pretreated with 30 nM cryptopleurine for 12 h and then incubated with 20 ng/ml TNF-α for 24 h. Whole cell extracts were analyzed by Western blot using indicated antibodies for cleaved capase-8, cleaved capase-3, cleaved PARP, and tubulin.