CCR2 and lip and oral cavity carcinoma: Binding of CCL2 to its receptors (the most important of which is CCR2) triggers various signaling pathways, and eventually leads to various immune events, such as inflammation.[32] Previous studies have shown that the level of CCL2 in gingival crevicular fluid in periodontal lesions is up-regulated compared with healthy sites.[33] CCL2 has been considered as a potential candidate gene for oral cancer caused by chronic infection.[34]