CDC25A is overexpressed in JAK2^V617F-positive primary cells. (A) CDC25A expression was analyzed by Western blot in CD36⁺ cells purified from the BM of 4 JAK2^V617F-positive patients (PV, ET) and 3 healthy donors (HD). (B) Paraffin-embedded BM biopsies from 3 JAK2^V617F-positive PV patients, 1 JAK2^V617F-positive ET patient, and 2 HDs were subjected to an immunohistochemical staining for CDC25A. Pictures representative of JAK2^V617F-positive and control BM biopsies are shown. (C) Purified CD34⁺ cells from a JAK2^V617F-positive PV patient, 2 JAK2^V617F-positive ET patients, and 2 representative healthy controls (HD) were grown in liquid erythroid differentiation medium. Cells were harvested at day 7, corresponding to a proerythroblast stage, and subjected to a Western blot analysis for CDC25A (left). The presence of CD36 and GPA markers was visualized by flow cytometry (right). (D) BM (left) and spleen lysates (right) from 3 WT and 4 Jak2^V617F KI mice were subjected to Western blot analysis for CDC25A. CDC25A expression in BA/F3 JAK2^V617F cell line was used as molecular weight control. β-actin or α-tubulin levels were used as control.