The mean inhibition of CLL cell viability (±SD) in the NOTCH1 wild type versus NOTCH1ΔCT mutated CLL cases at an inhibitor concentration of 0.5 μM after 3 days was as follows: 84% (±23%) versus 87% (±16%) for gliotoxin, 14% (±13%) versus 36% (±14%) for RO4929097, and 10% (±14%) versus 33% (±16%) for DAPT, respectively. This evidence concerns the gene NOTCH1 and B-cell chronic lymphocytic leukemia.