CCL2 and breast neoplasm: We analyzed the induction of chemotaxis on THP1 human monocytes by supernatants of the three main cell types and their co-cultures, and we also used recombinant and/or synthetic forms of some of the paracrine factors we propose may be present in the breast tumor microenvironment of obese females, e.g., leptin, the saturated FFA lauric acid and CCL2.