Intratumor depletion of NK cells or blockade of IFN-γ causes tumor outgrowth. C3B6F1 mice were subcutaneously inoculated with Ag104L^dLIGHT tumor cells with intratumor NK depletion by anti-asialo GM1 antibody (A) or blockade of IFN-γ via anti–IFN-γ mAb (B) at days 9, 12, and 15. Tumor growth was monitored every other day and data are the mean ± SD of 5 mice for each group.