Depletion of CD8+ T cells in EMT6 tumor-bearing mice resulted in increased local and distant metastasis, as demonstrated by live images of animals (Fig. 3a, b), as well as ex vivo images of lungs, livers, and spleens showed significantly higher luciferase activity in CD8+ T-cell-depleted animals (Fig. 3c). This evidence concerns the gene CD8A and neoplasm.