To further investigate the association between tumor-derived FOXO1 and M2 macrophage infiltration in vivo, we established FOXO1-transfected tumor cells (FOXO1(+)) and control (FOXO1(-)) cells (Figure S1E-H) and injected them subcutaneously into the left and right dorsal flanks of nude mice (n = 5), respectively. The gene discussed is FOXO1; the disease is neoplasm.