CXCR1 and osteosarcoma: It has been reported that CXCL6, CXCR1, and CXCR2 are aberrantly expressed both at the transcript and protein levels in several osteosarcoma cell lines and that the ectopic expression of CXCL6 enhances tumor growth, metastasis to the lungs, and the activation of Wnt/β-catenin and PI3K/AKT pathways in immunocompromised mice in vivo, suggesting the crucial role of the CXCL6/CXCR1 axis in facilitating the proliferation and metastasis of cancer cells [10].