Noteworthy, TIL populations contain not only CD8 T cells able to kill tumor cells and CD4 T helper cells that secrete cytokines supporting proliferation of other T cells, but also regulatory T cells (Treg) able to inhibit function and proliferation of other T cells, and T cells that secrete, e.g., chemokines attracting macrophages and vasoendothelial growth factor (VEGF) promoting neoangiogenesis. The gene discussed is CD8A; the disease is neoplasm.