Bortezomib is largely used in clinical practice in multiple myeloma [170] and is currently being tested in preclinical studies in T-ALL [54], where it was shown to cause cellular death in a large panel of T-ALL cell lines at sub-nanomolar concentrations, and to suppress the expression of Notch and its target genes (HES1, GATA3, and RUNX3), as well as to hamper NF-Kb activity. This evidence concerns the gene HES1 and acute lymphoblastic leukemia.