Dual PI3Kα/δ inhibition is required to block AKT and NF-κB activation in ABC-DLBCL PI3K regulates BCR-dependent and -independent NF-κB activation via p-IκBα and cIAPs PI3Kα/δ inhibitor copanlisib induced tumor regression in MYD88mut ABC-DLBCL in vivo Ibrutinib and copanlisib combination led to sustained complete response of DLBCL