The antileukemic effects of our combinatorial treatment of SAHA and DAC on AML cells are featured by the upregulated expression of proapoptotic proteins Bax and cytochrome c1, as well as a remarkable induction of the cell cycle protein, p21, and significant increase in the cleavage of procaspases 8, 9, and 3, as compared to the effect obtained by SAHA or DAC treatment alone. This evidence concerns the gene CYC1 and acute myeloid leukemia.