α2δ1 may be a potential marker for cancer stem cell in laryngeal squamous cell carcinoma.

Abstract

Cancer stem cells (CSCs) have the ability to dictate tumor initiation, recurrence, and metastasis. Here, we examined the expression of a21 in laryngeal cancer tissues and further determined the effect of 21 on the migratory ability and tumorigenicity of laryngeal cancer cells. Immunofluorescence staining revealed that 21 was positive in 13 (13/16, 81.25%) cases in laryngeal squamous cell carcinoma (LSCC) tissues, 7 (7/16, 43.75%) cases in paracancerous tissues and only 2 (2/16, 12.5%) cases in normal tumor tissues. Our quantitative RT-PCR assays further showed that 21 LSCC cells expressed significantly higher levels of stem cell-associated genes and drug efflux and resistance genes versus21 cells. Sphere-forming assays demonstrated higher sphere-forming efficiency in the 21versus21 subpopulation. Our Matrigel assays showed that 21 cells exhibited significantly greater invasive and migratory ability than 21 cells. Furthermore, the percentage of purified 21 in TU686 and TU212 cells treated cisplatin or paclitaxel was significantly higher than that of the control group. Tumor xenograft assays revealed that the tumorigenicity of 21 cells was much higher than 21 cells. In conclusion, a 21 subpopulation with CSC-like property was present in laryngeal cancer and possessed high self-renewal activity and was sufficient for tumor growth, differentiation, migration, invasion, and chemotherapeutic resistance. They could represent a promising therapeutic target for LSCC.