During the “elimination” phase, the natural killer (NK) cells, CD4+Th1, CD8+CTL (cytotoxic T lymphocyte), and cytokines including tumor necrosis factor-α (TNF-α), interferon-α, interferon-β, interferon-γ and interleukin-12(IL-12) are the primary factors to recognize and eliminate cancer cells (17). Here, CD8A is linked to cancer.