Advances in surface markers of liver cancer stem cell

Abstract

Liver cancer stem cells (LCSCs), a small subpopulation that constitutes liver cancer heterogeneity, play a vital role in cancer initiation, invasion, recurrence, metastasis, and resistance to chemo-radiotherapy. It is believed that therapies targeting LCSCs can improve the efficacy of conventional chemotherapy and radiotherapy by completely eliminating tumors while preventing recurrence. Therefore, during last decades, numerous surface markers for LCSCs have been identified and characterized in many subtypes of liver cancer, especially in hepatocellular carcinoma (HCC). These well-recognized surface markers significantly promote the therapeutic efficacy that identifies, targets and destroys LCSCs. Meanwhile, there have been intensive studies that aim to investigate the molecular mechanism of how stemness contributes to liver cancer relapse, recurrence and resistance. However, liver cancer stemness seems to be regulated by a hierarchical organization and crosstalk of a wide variety of signaling pathways. Using individual or few LCSC surface markers may not be able to completely reveal the intrinsic stemness hierarchy. From an integrated perspective, understanding of recent advances in LCSC surface markers remains important and urgent. In this review, we concentrate on demonstrating the indispensable roles of LCSC surface markers in identification and characterization of multiple cancer stages including initiation, invasion, metastasis, resistance and highlighting the cutting-edge therapeutic strategies against cancer stem cells in HCC.

Keywords

Liver cancer / hepatocellular carcinoma / cancer stem cell / surface marker

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