NOTCH1 and T-cell leukemia: Focusing more specifically on the trafficking of leukemia cells to the CNS, Buonamici et al. used murine T-cell leukemia models involving expression of the oncogenic, intracellular Notch1 fragment in hematopoietic progenitors combined with gene expression profiling to identify the chemokine receptor CCR7 as an essential adhesion molecule required for the infiltration of leukemic T-cells into the CNS (44).