SOCS3 and neoplasm: In this study, we successfully constructed a conditionally SOCS3 gene knockout mouse model in the myeloid lineage by using the murine Cre-loxP system (SOCS3KO) and detected a significant increase in the amount of CD11b+Gr-1− eMDSCs both in bone marrow (eMDSCsSOCS3KO) and tumor tissues (eMDSCsTumor) of tumor-bearing SOCS3KO mice.