Fig. 3.

AMP-activated protein kinase (AMPK) activation was responsible for the enhanced histone acetylation and cytotoxicity by the combination of simvastatin and romidepsin. (A) Cells were treated for 48 h with 5 μM simvastatin and 20 nM romidepsin with or without 5 μM compound C. Apoptotic cells were detected by annexin-V assay using flow cytometry. 10,000 cells were counted. Bar graphs show the increase in annexin-V positive cells. Data are expressed as mean ± SD from three independent experiments. FITC, fluorescein isothiocyanate; 7-AAD, 7-amino-actinomycin D. *p = 0.0495. (B) Western blotting for AMPK and acetylated histone. Cells were treated for 48 h with 5 μM simvastatin and 20 nM romidepsin with or without 5 μM compound C. Actin was used for the loading control. Representative blots are shown.