Chemoresistance of CD133+ cancer stem cells in laryngeal carcinoma

Background Mounting evidence suggests that tumors are histologically heterogeneous and are maintained by a small population of tumor cells termed cancer stem cells. CD133 has been identified as a candidate marker of cancer stem cells in laryngeal carcinoma. This study aimed to analyze the chemoresistance of CD133+ cancer stem cells.Methods The response of Hep-2 cells to different chemotherapeutic agents was investigated and the expression of CD133 was studied. Fluorescence-activated cell sorting analysis was used to identify CD133,and the CD133+ subset of cells was separated and analyzed in colony formation assays,cell invasion assays,chemotherapy resistance studies,and analyzed for the expression of the drug resistance gene ABCG2.Results About 1%-2% of Hep-2 cells were CD133+ cells,and the CD133+ proportion was enriched by chemotherapy.CD133+ cancer stem cells exhibited higher potential for clonogenicity and invasion,and were more resistant to chemotherapy. This resistance was correlated with higher expression of ABCG2.Conclusions This study suggested that CD133+ cancer stem cells are more resistant to chemotherapy. The expression of ABCG2 could be partially responsible for this. Targeting this small population of CD133+ cancer stem cells could be a strategy to develop more effective treatments for laryngeal carcinoma.