PDn. (A) XPO1 mRNA levels in PBMCs isolated from patients before and after the first dose of selinexor. Each point represents data from patients across all doses normalized to the predose level, with the number of patients per time point indicated on the graph. The Student t test was used to determine statistical significance (*P < .05; ***P < .0001 vs predose). (B-D) Assessment of protein and mRNA levels in patient-derived BM blasts. XPO1, p53, FLT3, and Kit protein levels were analyzed by western blot at baseline and near the end of cycle 1 (day 24). GAPDH was used as a loading control. (E) FLT3 and Kit mRNA levels from corresponding BM blast samples assayed in panel D.