“…Several chemokines derived from bone-tropic tumor cells act as osteolytic factors by inducing bone resorption of osteoclasts and promoting the recruitment and differentiation of osteoclast precursors (14)(15)(16), and the levels of these chemokines in serum or bone marrow are associated with cancer-mediated osteolysis in humans (17,18). In the case of OSCC, various chemokines, including CXCL12/CXCR4, CCL5/CCR5, CXCL8, and CCL2, are known to play critical roles in invasion and metastasis by promoting EMT, MMP expression, and cell dissemination (19)(20)(21). OSCC cell-derived CXCL2 and CXCL13 induce RANKL expression in osteoblastic/stromal cells (22,23), and serum levels of CXCL9 and tissue expression of CCL2 are positively correlated with OSCC bone invasion (24,25).…”