CXCL12 and cancer: Bone cells can release factors like CXCL12 to promote cancer cell bone metastasis, and the abundant blood supply and continuous remodeling process in bone create a permissive microenvironment: osteoblasts and osteoclasts secrete chemokines that recruit these cancer cells, subsequently triggering bone destruction while promoting cancer cell proliferation and differentiation (Hiraga et al., 2012).