Embryonic stem cell markers Sox-2 and OCT4 expression and their correlation with WNT signal pathway in cervical squamous cell carcinoma

BACKGROUND: Both the expression of embryonic stem cells (ESCs) markers (Sox2, Oct4) and the Wnt signal pathway (β-catenin) are crucial for progression of various human malignancies. The purpose of this study was to investigate the clinicopathologic significance of Sox2, Oct4 and β-catenin in cervical squamous cell carcinoma (CSCC) and to study their correlation with the occurrence and prognosis.

METHODS: Sox2, Oct4 and β-catenin were assessed using immunohistochemistry in normal cervix tissues (n=28) and invasive cervical squamous cell carcinoma (n=43). Associations of Sox2, Oct4 and β-catenin levels with clinicopathological characteristics and with overall survival were studied using uni- and multivariate analysis.

RESULTS: The expression levels of Sox2, Oct4 and β-catenin were highly increased in CSCC compared with the normal cervix tissues. The ESCs markers expression (Sox2 and Oct4) correlated significantly with β-catenin expression. High expression of Sox2, but not that of Oct4 or β-catenin, was correlated with poorer differentiation (P<0.05). Furthermore, Sox2 expression was significantly correlated with patients' status of survival in advanced CSCC (P<0.05), whereas there was no significant finding in Oct4 or β-catenin expression.

CONCLUSIONS: These findings provide evidence that both ESCs biomarkers (Sox2, Oct4) and Wnt signal pathway (β-catenin) are activated in CSCC. Sox2 can be regarded as a novel predictor of poor prognosis for CSCC patients.