The resulting cross of HGFL−/− mice into the PyMT model showed a significant impairment of tumor growth, metastasis, and tumor characteristics that were repeatedly observed in several in vivo experiments upon loss of HGFL including reduced tumor cell proliferation, increased tumor cell death, elevated M1 (iNOS+) macrophage recruitment, diminished M2 (Arginase-1+) macrophage recruitment, and increased CD8a+ and CD4+ T cell recruitment. Here, ARG1 is linked to neoplasm.