[Progress and prospects in cancer stem cell research for hepatocellular carcinoma]

The cancer stem cell (CSC) theory stipulates that it is a small population of cells called CSCs that initiates tumor formation and maintains its growth. CSCs are scarce within the bulk of the tumor mass, and possess stem cell-like properties such as self-renewal, differentiation and resistance to therapies, and so on. In the past few years, by using side population technique and approaches based on surface markers, including CD133, CD90, OV6 and EpCAM, researchers have identified and isolated a subpopulation of liver cancer cells with enhanced colony-forming and tumorigenic ability, which is strong evidence for the existence of liver CSCs. In this review, we summarized the progress of research on liver CSCs, discussed the significance of liver CSCs in the diagnosis and treatment of hepatocellular carcinomas, and put forward the future research directions as well as the challenges and opportunities.