They suggested that MRC1+ CCL18+ TAMs might originate from Kupffer cells in the liver and found that M2 polarization-related genes (APOE, MARCO) were significantly upregulated in MRC1+ CCL18+ TAMs of CRLM, while MRC1+ CCL18+ TAMs of primary CRC showed higher expression of inflammatory cytokines (TNF, IL1B, CCL3, and CCL4). This evidence concerns the gene CCL18 and colorectal carcinoma.