CD44 and hepatocellular carcinoma: Since then, according to xenotransplantation experiments, several cellular biomarkers of CSCs in HCC have been identified, including epithelial cell adhesion molecule (EpCAM), CD133, CD44, CD90, CD13, CD24, OV6, CD47, calcium channel α2δ1 isoform5, and intercellular adhesion molecule 1 (ICAM-1) 6, 16.