CD8+T cells are the dominant effector cells of anti-tumor immune response, which can bind to helper T1 cells and release perforin, granulozyme and tumor necrosis factor-α (TNF-α) to directly kill tumor cells and mediate anti-tumor immune response.[21] However, the activity of CD8+T cells is suppressed to some extent in the TME. The gene discussed is CD8A; the disease is neoplasm.