TSA and/or TPX induced differentiation in both myeloid (e.g., U937) and erythroid (e.g., K562) cell lines. Co-treatment with ATRA resulted in a synergistic enhancement of differentiation. In clinical AML specimens ranging from M0 to M7, TSA alone elicited morphological and phenotypic changes in 12 of 35 samples (34%). This evidence concerns the gene TPO and acute myeloid leukemia.