CXCL16 and liver cancer: Other angiocrine factors implicated in tumor metastasis include ANGPT2, IL-8, CXCL16, and CCL2 in liver cancer [40]; IL-6, TGF-β, and MMP9 in prostate cancer [41]; CXCL5 in head and neck cancer [42]; CXCL1 in gastric cancer [43]; IL-6, G-CSF, GM-CSF, and sICAM1 in colorectal cancer [44]; and lysyl oxidase (LOX) in renal carcinoma [45], all of which have been implicated in metastasis.