IFNG and neoplasm: Nevertheless, the activation of anti-tumor immune responses contributes substantially to the anti-tumor effect , for the reason that: 1) the combination treatment resulted in a massive infiltration of IFNγ-producing cells to the tumor; 2) anti-tumor effect of the combination therapy was reduced in IFNγ KO mice; 3) the number of splenic MDSCs was markedly reduced and the residual MDSCs showed a more mature phenotype; 4) tumor-free mice after CY+1D11 treatment developed long term anti-tumor immunity.