The secretion of IFN-γ from CD8+ T cells showed no significant differences with or without pep-20 treatment after macrophages depletion despite the increase of CD8+ T cells population in the tumor tissue, indicating the critical role of macrophages in mediating the antigen cross-presentation and thus activating the CD8+ T cells (figure 4C–E). This evidence concerns the gene CD8A and neoplasm.