ABI1 is downregulated in hematopoietic progenitor cells and granulocytes obtained from patients with MPNs. (A) Reverse transcription (RT)-PCR analysis of ABI1 transcript levels in CD34⁺ cells isolated from the bone marrow aspirates of patients with PMF (n = 5) or healthy control patients (n = 5). ABI1 gene expression was normalized to RPP14 (RNaseP) and ACTB. (B) RT-PCR analysis of ABI1 gene expression in peripheral blood granulocytes from patients with PMF (n = 36), ET (n = 15), PV (n = 20), myelofibrosis post-ET (n = 5), and post-PV (n = 9) or from healthy controls (n = 16), normalized to RPP14. (C) RT-PCR analysis of ABI1 gene expression in peripheral blood granulocytes from patients with PMF with JAK2 (JAK2 V617F) or CALR mutations (Del52 or Ins5), normalized to RPP14. Clinical details of the analyzed samples are presented in supplemental Table 1. Boxes represent the interquartile range that contains 50% of the subjects, and the horizontal line in the box indicates the median. *P < .05, ***P < .001.