Here, we show that estrogen deprivation triggers a broad immunosuppressive transcriptional program in ER+ BC cells, which includes the secretion of cytokines that activate NF‐κB signaling such as TNF‐α, but also additional cytokines such as IFN‐γ and IL‐6 that trigger the activation of the JAK/STAT pathway. The gene discussed is NFKB1; the disease is breast cancer.