Background
Myeloproliferative neoplasms (MPN) are clonal hematopoietic stem cell malignancies comprising several diverse pathologies. The 2008 World Health Organization (WHO) classification incorporated JAK2 V617F mutation status into the diagnosis of BCR-ABL negative MPN [1]. This mutation is the most frequent somatic change in MPN, occurring in over 95% of patients with polycythemia vera (PV) and in 50% of patients with essential thrombocythemia (ET) or primary myelofibrosis (PMF) [2]. The valine to phenylalanine substitution at amino acid 617 causes a disruption of the auto-inhibitory JH2 domain of JAK2, leading to constitutive activation of the JAK2 tyrosine kinase activity and a consequent loss of control in cell proliferation and growth [3,4]. Small-molecule inhibitors targeting JAK2-driven cancers have recently entered clinical trials [5,6].