In an elegant high-content screening study using a library of 313 cytokines, the positive regulators of primitive CML cells were screened, and it was identified that IFN-γ, IL-1β, and IL-6 had growth-promoting effects along with IL-3, IL-1α, and granulocyte-macrophage colony-stimulating factor (GM-CSF) as reported earlier (von Palffy et al., 2020). Here, CSF2 is linked to chronic myelogenous leukemia, BCR-ABL1 positive.