For example, tumor infiltration by CD8+ effector T cells is associated with significant antitumoral response and longer survival in breast carcinoma.13 Conversely, TReg cells, which normally suppress self-reactive T cells to fight autoimmune diseases, are believed to contribute to tumor tolerance by suppressing other immune cells.13 However, the overall percentage of lymphocytes in the tumor bed observed without subtyping are still predictive of better prognosis in TNBC and HER2+ breast cancer.12,18–20. Here, CD8A is linked to autoimmune disease.