[Expression of Oct4 and Sox2 and their clinical significance in tongue squamous cell carcinoma].

Objective: To investigate Oct4 and Sox2 protein expression in tongue squamous cell carcinoma (TSCC) and the relationships between the expressions of Oct4 and Sox2 and clinical pathological characteristics and survival of patients. Methods: The paraffin imbedded tissue specimens of 51 patients with histologically confirmed TSCC were included. Immunohistochemistry was employed to detect the protein expression of Oct4 and Sox2 in 51 TSCC tissue samples. The protein expression levels of Oct4 and Sox2 and their relationships with both clinicopathological features and survival of patients with TSCC were evaluated. Results: In 51 TSCC cases,positive expressions of Oct4 and Sox2 were mainly located in the nucleus of tumor cells. The expression of Oct4 was strongly positive in 27 cases (53%), weakly positive in 16 (31%) and negative in 8 (16%), whereas that of Sox2 was strongly positive in 25 cases (49%), weakly positive in 22 (43%) and negative in 4 (8%). Oct4 and Sox2 expression levels were significantly correlated with the histological grade of TSCC (P=0.004, P=0.006, respectively), not correlated with age, gender, T stage, tobacco smoking and alcohol consumption status (P>0.05), but Oct4 expression level was significantly associated with lymph node metastasis (P=0.001). Sox2 expression level was not associated with lymph node metastasis (P>0.05). The expression of Sox2 was significantly correlated with Oct4 (P<0.001). Oct4 and Sox2 expression was associated with poor overall survival of patients with TSCC (P=0.001, P=0.002, respectively), cases with higher Oct4 and Sox2 expression had the poorest overall survival (P<0.001). Sox2 expression and lymph node metastasis were independent prognostic factors of overall survival in patients with TSCC (P=0.02, P=0.001, respectively). Conclusions: Sox2 had independent prognostic effects on overall survival, suggesting that Sox2 expression may be an usefull indicator for predicting the prognosis of patients with TSCC.