Consequently, as we demonstrated, the addition of the SMAC mimetic birinapant to ET increased the expression of NF-κB immune target genes, leading to the migration of T cells toward ER+ breast cancer cells and MHC-I-specific T-cell–mediated cell death in ER+ breast cancer cells, while also increasing tumor regression in a cell autonomous manner. The gene discussed is NFKB1; the disease is breast carcinoma.