Increased expression of CRLF2 independently has been correlated with a poor prognosis in B-ALL, and the synergistic effects of CRLF2 overexpression and JAK2 constitutive activation may play a major role in the leukemogenesis of the disease that can be prognostically considered and therapeutically targeted [8]. This evidence concerns the gene JAK2 and precursor B-cell acute lymphoblastic leukemia.