Effects of SIRT inhibitors on the MCF-7 cell cycle. MCF-7 cells were treated with 50 μM of compound 8, salermide, sirtinol, AK-7 and EX-527 for 24 h. Flow cytometric analysis of DNA content was performed after propidium iodide staining. Percentage of cells in each phase of the cell cycle (sub-G1, G1, S and G2-M) is indicated. Representative data from three independent experiments are shown.