GPD induces apoptosis in SK-MEL-28 human melanoma cells.

(A) GPD induces apoptosis in SK-MEL-28 cells. Cells (1.2×105/60 mm dish) were incubated with or without 20 µM, 40 µM of GPD or 40 µM Rb1 for 48 h and apoptotic cells were stained with annexin V and propidium iodide (PI). (B) Apoptosis was determined by Fluorescence Activated Cell Sorting (FACS). The results are shown as mean of total apoptosis % ±SE (n = 3). The asterisk (**) indicates a significant difference (pMaterials and Methods. (D) The expression of the apoptotic markers cleaved PARP and cleaved caspases 3, 7 and 9, increased after 40 µM of GPD treatment, as confirmed by western blot analysis.