In three distinct murine models of AMKL carrying CBFA2T3::GLIS2 alone, in combination with JAK2 p.V617F, or with copy number alterations on chromosome 21, ruxolitinib significantly prolongs survival, justifying its therapeutic testing in pediatric AMKL (Drenberg et al., 2019). The gene discussed is GLIS2; the disease is acute megakaryoblastic leukemia.