Finally, we analysed the overall survival of breast cancer patients using TCGA data and found patients with low CD8+ T-cell level and high levels of platelets and MDSCs had low survival probability compared to those with high levels of CD8+ T cells and low levels of platelets and MDSCs (log-rank test, HR = 5.09 (2.04–12.65), P = 0.00011) (Supplementary Fig. S6d). The gene discussed is CD8A; the disease is breast cancer.