Cancer Stem Cells in Hepatocellular Cancer

Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide and typically portends a poor prognosis with a median survival ranging from 6 to 16 months. In the United States, a total of 24,120 new cases of primary liver cancers and 18,910 deaths are projected to occur in 2010. Associated factors potentially contributing to this abysmal prognosis include delayed diagnosis, underlying cirrhosis, and resistance to chemotherapy. Recently, compelling evidence has emerged in support of the cancer stem cell (CSC) hypothesis for many solid organ cancers including hepatocellular cancer (HCC). CSCs are postulated to account for tumor initiation, therapeutic resistance, and relapse following surgery or therapy. Identification, proper characterization, and understanding the biology of the HCC-derived CSCs (HCSCs) are imperative for improving early detection and treatment outcomes. If proven correct, the CSC hypothesis may herald a paradigm shift in the treatment of this deadly disease. This chapter summarizes the differences between HCSCs and normal liver stem cells through state-of-the-art identification and characterization, and then assesses the clinical correlation and potential novel therapeutic strategies based on HCSCs.