Therefore, we analyzed the cytotoxic activity of OVA peptide-stimulated splenocytes obtained from the mice immunized with IL-15:IL-15Rα-B16F10-OVA, control-B16F10-OVA cells, or the “no virus group” against two OVA-expressing cancer cell lines, B16F10-OVA or E.G7-OVA lymphoma cells. This evidence concerns the gene IL15 and cancer.