To thoroughly understand the role of cytokines in mediating AML cell survival, Carey et al. used a unique ex vivo screen; cell viability was tested in the presence of 94 different cytokines, and only a few cytokines could significantly promote cell growth, including IL-1, GM-CSF, IL-3, M-CSF, G-CSF, and TNF-a. The gene discussed is CSF1; the disease is acute myeloid leukemia.