Effect of Ezrin on epithelial⁃to⁃mesenchymal transition in human tongue squamous cell carcinoma with cisplat⁃ in⁃resistance

Objective To investigate the effect of Ezrin on epithelial⁃to⁃mesenchymal transition(EMT) in human tongue squamous cell carcinoma (TSCC) with cisplatin⁃resistance. Methods A MTT⁃based method was used to analyse the half maximal inhibitory concentration (IC50) values of TSCC cell line CAL27 and its cisplatin ⁃ resistant cell line CAL27/CDDP. Bright⁃phase microscopic was used to observe the morphological changes. Western blot was used to de⁃ tect for Vimentin, E⁃cadherin and Ezrin expression. Transwell assay was used to detect for invasion. After transfected Ezrin with siRNA, Ezrin, Vimentin and E⁃cadherin expression, as well as invasion, were furthered detected in CAL27/ CDDP. Results IC50 of CAL27/CDDP increased by 6.8 fold compared to its parent cell line. CAL27 cells with polygo⁃ nal morphology stimulated by cisplatin trans⁃differentiated into epithelioid structure with clustered shape and tight con⁃ nection between the cells whereas CAL27/CDDP showed a mesenchymal phenotype with an elongated morphology. CAL27/CDDP showed upregulated Vimentin, downregulated E⁃cadherin and upregulated Ezrin expression, as well as in⁃ creased invasion. After knocking down Ezrin with siRNA, Ezrin and Vimentin were downregulated but E⁃cadherin was upregulated in CAL27/CDDP, as well as decreased invasion. Conclusion Knocking down of Ezrin inhibits epithelial⁃to⁃ mesenchymal transition and metastasis in TSCC with cisplatin⁃resistance.