CCL2 and breast cancer: BMSCs can be recruited by all kinds of chemokines in various cancers, for example CXCL16 in prostate cancer,4 CXCL12 in breast cancer,5 CXCL8/IL‐8, CCL2/MCP‐1 and CXCL1‐2‐3/GRO that play a role in the homing of BMSCs to liver tumour sites,6 CCL5,7 TGF‐β and interleukin‐17b,8 CXCL10, placental growth factor 9 and platelet‐derived growth factor receptor beta.10