Remarkably, using a pre-clinical mouse model of breast cancer brain metastasis (BCBM), Uceda-Castro and colleagues discovered that doxorubicin-induced senescence in BCBM tumor cells triggers a significant recruitment of PD-1+ CD8+ T lymphocytes to BCBM lesions thus promoting the efficacy of anti-PD-1 treatment [212]. The gene discussed is CD8A; the disease is neoplasm.