Later on, the same group revealed that T-ALL generated from fetal liver (FL) and adult BM have a dramatic difference in their T-LIC activity, i.e., that FL-derived leukemia with robust NOTCH1-driven autocrine IGF1 signaling exhibits 2-log lower T-LIC activity compared to BM-derived leukemia [98]. Here, IGF1 is linked to acute lymphoblastic leukemia.