CXCR4 and colorectal carcinoma: Along this line, another study described CD44v6 as a CSC marker in CRC and showed that its expression seemed to be induced by factors like osteopontin and hepatocyte growth factor (HGF), which promoted CXCL12/CXCR4 axis activation and induced a more metastatic phenotype in the CRC CSC population [24].