Thus, we sought to examine (1) whether molecularly characterized LIC can be identified among specific hematopoietic subpopulations in pediatric T-ALL without preceding in vitro culture, (2) the role of NOTCH1 activation in LIC propagation, and (3) whether LIC have an intrinsic predilection for specific hematopoietic niches. This evidence concerns the gene NOTCH1 and acute lymphoblastic leukemia.