Alternatively, MSCs are consistently attracted to the TME via various signaling molecules such as VEGF, IGF1, bFGF, HGF, CCL-5, CXCL-16, and TGF-β, which are produced by immunosuppressive cells, cancer-associated fibroblasts (CAFs), and BC cells (Fig. 9) [254]. Here, CCL5 is linked to breast cancer.