In addition, breast cancer cells treated with the conditioned medium from human adipose tissue-derived macrophages exhibited enhanced malignant phenotypes, and these macrophages over-expressed a cluster of cancer-associated genes, with the C-X-C chemokine ligand 1 (CXCL1) and C-X-C chemokine ligand 5 (CXCL5) being mostly upregulated18. Here, CXCL5 is linked to breast cancer.