IL-12 and iNOS showed a significant increase in the Ndrg2−/−mφ MIX group, while Arg-1 was reduced (Fig. 4c), indicating that premixed Ndrg2−/− macrophages not only tended to polarize toward an M1-like phenotype and suppress tumor growth but also could re-educate recruited macrophages toward a tumor-suppressor phenotype. Here, ARG1 is linked to neoplasm.