The majority of studies reported MCP-1 related to tumor progression, clinical aggressiveness, and the promotion of metastasis, with a prevalent worse effect for digestive tract, urogenital, and head neck tumors, but no detrimental effect has been observed in pulmonary tumors [70], and a reduced metastatic potential has been reported in a murine model of colon cancer and in pancreatic cancer [71, 72]. This evidence concerns the gene CCL2 and head and neck neoplasm.