Targeting the Inactive Conformation of JAK2 in Hematological Malignancies.

Activating JAK2 mutants cause hematological malignancies. Current clinical type I JAK2 inhibitors effectively relieve symptoms but fail to resolve the disease. In this issue of Cancer Cell, two articles by Wu and colleagues and Meyer and colleagues characterize a type II JAK2 inhibitor that is effective in preclinical models of JAK2-dependent myeloproliferative neoplasms and B cell acute lymphoblastic leukemia.