Taurolidine induces epithelial-mesenchymal transition via up-regulation of the transcription factor Snail in human pancreatic cancer cell lines

Abstract

Purpose: The taurine derivative taurolidine (TRD) exerts anti-neoplastic effects in a variety of tumor models. On the other hand, TRD at low doses was shown to reduce cell-cell adhesion, a prerequisite for metastasis. The aim of this study was to elucidate the effects of low-dose TRD on pancreatic cancer. Methods: Human pancreatic cancer cell lines representing diverse states of differentiation were exposed to TRD for 24 h. Cell viability was assessed by MTT assay and trypan blue staining, apoptosis by caspase-3/7 activity, and flow-cytometric cell cycle analysis. Expression of Snail and E-cadherin was analyzed by polymerase chain reaction and Western blotting. Results: MTT-tested viability of all pancreatic cancer cell lines decreased dose-dependently up to 50 % of the untreated control. In contrast to staurosporine TRD (100 and 250 μM) did not induce apoptosis but increased the percentage of cells in G1/G0 arrest. Correlation of MTT test and trypan blue staining revealed a decreased adherence of vital tumor cells at 250 μM TRD. This was associated with reduced expression of the adhesion molecule E-cadherin and an increased expression of the transcription factor Snail, a regulator of epithelial-mesenchymal transition (EMT). Conclusion: Low-dose TRD reduces not only viability but also cell-cell adherence and E-cadherin expression of pancreatic cancer cells, whereas the expression of the EMT inducer Snail was increased. By induction of these EMT hallmarks, low-dose TRD may promote metastasis in pancreatic cancer.