NOTCH1 and acute lymphoblastic leukemia: We then extended our analysis to include a human T-ALL cancer cell line (CUTTL1) that is sensitive to GSI treatment, and in which Notch1 is both constitutively cleaved and activated in a ligand-independent manner, and in which both endogenous Notch1 activity and nuclear abundance are high (Fig. 1K, Extended Data Fig. 3:I/M)7–9,50–52 .