XIAP and mantle cell lymphoma: Moreover, simultaneous use of ibrutinib and bortezomib synergistically increased mitochondrial injury and apoptosis in diffuse large B cell lymphoma (D LBCL) and Mantle cell lymphoma (MCL) cells, with significant AKT and NF-κB inactivation, decrease in Mcl-1, BCL-XL, and X-linked inhibitor of apoptosis protein (XIAP), and increased DNA damage and endoplasmic reticulum stress [25].