Snail family proteins in cervical squamous carcinoma: Expression and significance

Abstract

Epithelial-mesenchymal transition (EMT) is crucial for tumor progression and metastasis. Snail family members, including Snail, Slug and Smuc, are the transcription factors that repress E-cadherin expression and induce epithelial-mesenchymal transition in some tumor tissues. In this study, the expression of snail family proteins in cervical squamous cancers was evaluated. A series of 144 samples, comprising 28 cases of normal cervical tissues and 116 cases of squamous cell carcinoma (SCC), were used for analysis. The expression of Snail, Slug, Smuc, E-cadherin and vimentin was assessed in the tissues by immunohistochemistry and was statistically analyzed by SPSS13.0. The increase in nuclear expression of snail and smuc was associated with down-regulation of E-cadherin and up-regulation of vimentin. The nuclear expression of Snail and Smuc was positively associated with lymph node metastasis of the SCC, and the nuclear expression of Snail was also positively related with histological differentiation. In contrast, tumor size, histological differentiation, lymph node metastasis and stages of the SCC were not associated with the expression of Slug, cytpolasmic Smuc or cytoplasm levels of Snail. Snail and Smuc proteins, but not Slug, may contribute to the onset of EMT in SCC. Inhibiting the expression of Snail and Smuc might be a potential therapeutic target for the treatment of metastasis and invasion of cervical carcinomas.