CD166 promotes cancer stem cell-like phenotype via the EGFR/ERK1/2 pathway in the nasopharyngeal carcinoma cell line CNE-2R

Aims: The present study aimed to investigate the role and underlying mechanisms of CD166 in cancer stem cell-like (CSCs) phenotype of the radioresistant nasopharyngeal carcinoma cell CNE-2R. Main methods: Established CD166-shRNA- CNE-2R cell line by lentivirus-mediated silencing CD166. Then, CSC-related genes mRNAs and proteins, and EGFR/ERK1/2 signaling pathway were detected using RT-PCR and western blot. Sphere formation assay was performed to evaluate the sphere formation capacity in CD166-shRNA-CNE-2R cells. The tumorigenesis ability in vivo was examined in nude mice mode. Key findings: Downregulation of CD166 inhibited the expression of the CSC-related genes, pEGFR and pERK in vitro and vivo. The capacity to form spheres and tumorigenesis was significantly decreased in CD166-shRNA cells. Furthermore, EGF-stimulated CD166-shRNA cells exhibited an increase in CSC-like traits by activating EGFR/ERK1/2 signaling. Significance: CD166 induced CSCs formation by activating the EGFR/ERK1/2 signaling pathway in nasopharyngeal carcinoma, which may serve as a critical molecular target for NPC therapeutic strategies.