Objective quantification of staining intensity per high power field view showed a significant increase in galectin-1 with progression to myelofibrosis across patient groups (Fig. 7B, P < 0.001 for myelofibrosis vs. healthy donors and P < 0.001 for myelofibrosis vs. ET and PV). This evidence concerns the gene LGALS1 and acquired polycythemia vera.