Furthermore, in lung metastatic tumor model, we also found that compared to without lung metastatic mice, the percentage of CXCR2+ MDSCs in peripheral blood was higher in mice with lung metastasis (76.8 ± 4.0% vs 55.7 ± 3.0%), and the number of CXCR2+ MDSCs in 1g spleen and 1g primary tumor was also higher in mice with lung metastatic (33070.7 ± 2718.0 vs 20648.6 ± 1932.2 in 1g spleen, 7916.5 ± 1079.8 vs 3814.2 ± 1090.3 in 1g primary tumor), and the number of CXCR2+ MDSCs in 1g lung was higher in mice with lung metastatic mice (254317.1 ± 38711.1 vs 64163.3 ± 39316.9) (Figure 3C–3F). The gene discussed is CXCR2; the disease is neoplasm.