These strong indications of biological relevance and therapeutic potential of targeting Notch1 in glioblastoma, together with recent promising results on a new anti-Notch1 directed drug candidate20, the first-in-man tested humanized anti-Notch1 blocking antibody termed brontictuzumab (BRON), in other cancers21–23 encouraged us to study the biologic consequences of BRON on models systems of glioblastoma stem-like cells. The gene discussed is NOTCH1; the disease is glioblastoma.