ERN1 and melanoma: To further prove that tumorous IRE1α-induced potentiated activation of CD8+T cells was dependent on NF-κB signaling, co-culture system harboring both melanoma cells and PBMCs were employed, in which A2058 or A375 melanoma cells were pre-stimulated with HA15 (10 μM for both A2058 and A375) for 24 h to induce intracellular ER stress and UPR activation, and meanwhile triggered little reduction of cell viability (Additional file 1: Fig. S6A).