NOTCH1 and neoplasm: Collectively, results show that bortezomib can restore Notch signaling in anti-tumor CD8+ T cells by enhancing a crosstalk between Notch and NFκB pathways via its multiple effects on the expression of Notch1 and Notch2 receptors, NICD, and downstream Notch genes, together with increased phosphorylation of the IκB kinase, IκBα and p65, which subsequently stimulate NFκB activity.