STAT1 and anaplastic large cell lymphoma: Stimulation with these cytokines led to increased phosphorylation levels of STAT1, STAT5 and ERK1/2, but not STAT3, in ALCL cell lines except for SUP-M2 (IL-2Rγ-negative) and Jurkat (IL-2Rα- and IL-2Rβ-negative; Fig. 3c and Supplementary Fig. 4e, f).