IGF1 Brings Growing Pains for T-ALL LSCs.

Hematopoietic progenitors undergo marked shifts during transition from fetal to postnatal life, and the implication of these changes for the cell-of-origin of childhood leukemia are unclear. In this issue of Cell Stem Cell, Giambra et al. (2018) show that epigenetically regulated IGF1 signaling regulates the ability of fetal-liver- or bone-marrow-derived cells to initiate T-ALL.