Effect of miR-200b on gemcitabine induced epithelial mesenchymal transition in pancreatic cancer cell line MiaPaCa-2 / 中华胰腺病杂志

ABSTRACT

Objective To investigate the role of miR-200b on gemcitabine induced epithelialmesenchymal transition (EMT) in pancreatic cancer cell line MiaPaCa-2.Methods Different concentrations of gemcitabine were used to induce MiaPaCa-2,and the concentration of 50％ cell proliferation inhibited (IC50) was applied to obtain drug-resistant MiaPaCa-2 cells.MiR-200b or nonsense small molecular fragments (negative control,NC) was transfected into MiaPaCa-2 cells by liposomes,then gemcitabine of IC50 was used to induce cells to obtain drug-resistant MiaPaCa-2 cells transfected with miR-200b or NC.The morphological characteristics of MiaPaCa-2 cells were observed by inverted microscope.Invasion of cells were detected by transwell chamber.The expression of miR-200b was measured by using real-time PCR.The expressions of Ecadherin,Vimentin,Zebl,Zeb2 proteins were determined by Western blot.Results After gemcitabine treatment,the cells' size gradually diminished,intercellular junctions decreased,pseudopodium increased,which presented the characteristics of mesenchymal morphology.The invaded cell number increased from (26 ± 3) to (85 ± 6),and the expression of Vimentin Zebl,Zeb2 was increased to (1.87 ± 0.17),(2.57 ±0.21),(5.24 ± 0.83) folds of the parent cells.The expression of miR-200b was decreased to (0.36 ± 0.01)folds of the parent cells,and the expression of E-cadherin was decreased to 0.47 ± 0.05 folds of the parent cells,while the invaded cell number of drug-resistant MiaPaCa-2 transfected with miR-200b was decreased to (42 ± 4),and the expression of Zebl,Zeb2 was decreased to (0.36 ± 0.07),(0.08 ± 0.01) folds of drugresistant MiaPaCa-2 transfected with NC.Conclusions The occurrence of EMT is observed in pancreatic cancer cell line MiaPaCa-2 during gemcitabine induction,and miR-200b down-regulation may be a possible mechanism.