The presence of 10 μM NSC95397 during culture had no significant effect on viability, neither when analyzing the overall results for the 79 patients (median 35%, range 6%–80%), nor when comparing various patient subsets that differed with regard to AML cell differentiation (morphology according to the FAB classification, expression of the CD34 stem cell marker), cytogenetic abnormalities, or Flt3/NPM1 mutations (data not shown). The gene discussed is NPM1; the disease is acute myeloid leukemia.