Over-expression of prolyl isomerase Pin1 promotes cervical tumorigenesis and metastasis.

Overexpression of the prolyl isomerase PIN1 is involved in tumorigenesis, but the role of PIN1 in cervical cancer is unclear. In this study, we examined PIN1 protein expression by immunohistochemistry in 221 paraffin-embedded samples from cervical cancer patients, cervical intraepithelial neoplasia patients, and control tissues, and found that high expression of PIN1 was significantly associated with lymph node metastasis (P=0.002), advanced stage according to the International Federation of Gynecology and Obstetrics guidelines (P=0.026). When endogenous PIN1 expression was knocked down using siRNA, cell proliferation, colony formation, migration, and invasion were inhibited in the SiHa cervical cancer cell line. Additionally, PIN1 knockdown increased E-cadherin and β-catenin expression, and decreased expression of N-cadherin and Vimentin, suggesting that PIN1 can promote epithelial-mesenchymal transition (EMT). These results indicate that the Overexpression of the prolyl isomerase PIN1 in cervical cancer indicates tumor-Promotive properties of PIN1 that may be a marker of poor prognosis in cervical cancer patients, and the molecular determinants of epithelial polarity which have tumorigenesis enhancing impact, might through EMT.