HEY1 and T-cell acute lymphoblastic leukemia: Only a few genes, such as HES4, HEY1, MYC, NOTCH3, NRARP, and TFRC, are similarly regulated in mutationally activated NOTCH1-driven cancers, such as T-cell acute lymphoblastic leukemia (T-ALL), mantle cell lymphoma (MCL), and breast cancer [83].