MEIS1 and acute myeloid leukemia: Moreover, we found a significant association between low or no PU.1 protein expression and high expression of HOXA9 and MEIS1 (78.2% compared with 10% for HOXA9-overexpressing samples, p < 9 × 10−6, Fisher's exact test) in our AML patient cohort (Figures 5D and 5E).