CRLF2 and acute lymphoblastic leukemia: Transphosphorylation of JAK2 by JAK1 or TYK2 does not confer resistance to BBT594 [16], and CHZ868, a benzimidazole analogue JAK2 type II inhibitor, was recently shown to have superior activity in blocking JAK2 signaling in Ph-like cell line model BaF/3 expressing Ph-like related genes and murine transgenic Ph-like ALL model co-expressing CRLF2 and mutant JAK2 R683G [15].