CXCL12 and colorectal cancer: After the injection of exosomes collected from a colorectal cancer cell line (HT-29) with liver-targeted metastatic properties, the mice implanted with Caco-2 cells (low metastatic colorectal cancer cell line) show an increase in the hepatic burden of metastasis via the SDF-1α/CXCR4 axis [59].