In the mice, TAMs are mainly derived from bone marrow monocytes (TAMs in human HCC arise from CCR2+ monocytes) that can recruited by inflammatory signals released by cancer cells in both the primary and metastatic tumors, and they can differentiate into TAMs under the action of chemokines and growth factors produced by the stromal cells and tumor cells, thus promoting tumor progression [20–23]. Here, CCR2 is linked to hepatocellular carcinoma.