Evaluation of histone acetylation in patient peripheral blood samples and bone marrow biopsies. Induction of histone H3 acetylation was rapidly induced in (A) patient peripheral blood (100 mg, n = 3; 150 mg, n = 3; 200 mg, n = 6; 250 mg, n = 6) and (B) bone marrow cells, and generally returned to baseline levels by the end of cycle 1. Some of the hyperacetylated cells appear to be leukemic blasts based on morphology. Error bars represent SD.