PDCD1 and neoplasm: Carfilzomib, a proteasome inhibitor approved by the FDA to treat relapsed/refractory multiple myeloma patients, has been supported to reprogram M2 macrophages into an M1-like population through IRE1a-TRAF2-NF-κB signaling and synergize with PD-1 inhibitors to reduce tumor growth in an autochthonous lung cancer model (158).