Epithelial-Mesenchymal Transition Predicts Survival in Oral Squamous Cell Carcinoma

Synergistic loss of E-cadherin and acquisition of vimentin are characteristic feature of epithelial-mesenchymal transition (EMT) which confers an invasive phenotype of epithelial cancer cells. The aim of the study was to evaluate the prognostic significance of E-cadherin and vimentin expression individually and in combination as a measure of epithelial-mesenchymal transition (EMT) in oral squamous cell carcinoma (OSCC). Expression of E-cadherin and vimentin through immunohistochemical analysis was examined in 200 patients with surgically resected OSCC. Combined E-cadherin and vimentin expression was evaluated to determine the EMT status. Kaplan-Meier curves and log-rank test were used to compare differences in survival. Cox regression analysis was performed to identify independent prognostic factors. E-cadherin expression was negative in 28 (14%) tumors, and vimentin expression was positive in 87 (43.5%) tumors. Moreover, 99 (49.5%), 87 (43.5%), and 14 (7.5%) tumors exhibited no, partial, and complete EMT, respectively. Both individual protein expression were significant prognostic factors [Negative E-cadherin, hazard ratio (HR) = 1.74, 95% confidence interval (CI) = 1.04-2.93; positive vimentin, HR = 1.64, 95% CI = 1.12-2.41]. For EMT status, the HR increased with EMT progression [partial EMT, HR = 1.64, 95% CI = 1.09-2.49; complete EMT, HR = 2.88, 95% CI = 1.44-5.79], of which, the complete EMT had higher HR than was individual protein expression. Combined E-cadherin and vimentin expression as a measure of EMT showed a superior prognostic significance compared with individual protein expression.