CD8A and neoplasm: Besides, in theory, radiation can induce tumor cell death, leading to tumor-antigen release and subsequent antigen-presenting process, alteration in tumor surface markers (e.g., MHC-I, FAS ligand, immune checkpoint molecules) expression, production of cytokines and chemokines, and recruitment of CD8 T cells and tumor-infiltrating lymphocytes, all of which exerts the immune-stimulation facility.