TGF-?1 And Trichostatin A Regulate Epithelial To Mesenchymal Transition(EMT) In Differentiated Pancreatic Cancer Cells

Background: In pancreatic cancer(PC),epithelial to mesenchymal transition(EMT)plays a significant role in disease progression,metastasis,and resistance to chemotherapy or radiation therapy.However,the molecular mechanism underlying EMT in various differentiated PC cells is unclear.Transforming Growth Factor-?1(TGF-?1)and trichostatin A(TSA)were recently found to regulate EMT in tumor cells.In present study,we aimed to explore the impacts of TGF-?1 and TSA on EMT and tumor metastasis in different PC cells.Methods: We used real-time RT-PCR and western blotting to measure the expression of EMT-associated markers in PC cells with differing degrees of differentiation: PANC-1(poorly differentiated),Patu8988(moderately differentiated),and SW1990(well-differentiated).Flow cytometry was performed to detect the percentage of CD24+CD44+ESA+ PANC-1 cells.The migratory and invasive capacity of PANC-1 cells was examined by transwell migration and invasion assay.Results: The m RNA expression levels of epithelial and mesenchymal markers were different in the three PC cell lines.Compared to Patu8988 and SW1990 cells,epithelial marker lowly expressed,and mesenchymal markers highly expressed in PANC-1 cells.TGF-?1 dose-dependently induced EMT as assessed by decreased expression of E-cadherin and increased expression of N-cadherin,fibronectin,and vimentin in the PANC-1 cells.TGF-?1 at 5ng/ml may have the best stimulation of EMT in PANC-1 cells.We found that TGF-?1 could not induce EMT in Patu8988 and SW1990 cell lines.TSA inhibited TGF-?1-induced EMT in PANC-1 cells,as evidenced by up-and down-regulation of E-cadherin and vimentin expression at protein and m RNA levels,respectively.Treatment of PANC-1 cells with TGF-?1 reduced the percentage of CD24+CD44+ESA+ cells,and this reduction was reversed by TSA treatment.TGF-?1 enhanced the migratory and invasive capacity of PANC-1 cells,and this effect was also suppressed by TSA.Conclusion: In PC cell lines with varying degrees of differentiation,TGF-?1 dose-dependently induced EMT in PANC-1 cells,but could not stimulate EMT in Patu8988 and SW1990 cells.In PANC-1 cells,the TGF-?1 EMT stimulation was reversed by TSA treatment.Furthermore,TGF-?1 and TSA have significant and opposing effects on EMT and CSC properties,as well as the migration and invasion of poorly differentiated PANC-1 cells.