NOTCH1 and acute lymphoblastic leukemia: Leukemic cells reside in the BM niche, which protects them from traditional chemotherapy.[21] We used an activated Notch1 mutant driven T‐ALL murine model, which presents over 60% human T‐ALL both phenotypically and genetically,[22, 23, 24, 25] to explore a functional nanocarrier that could target leukemic cells in BM (Figure S1a, Supporting Information).