For instance, compared to normal adipocytes, CAAs secrete a higher amount of leptin, IL-1b, IL-6, CCL5, MCP-1, TNF-α, VEGF and insulin-like growth factor binding protein-2 (IGFBP-2) which in turn promote invasion and metastasis of BC (24, 44, 45). Here, CCL2 is linked to breast cancer.