The Effect Of Transforming Growth Factor-β1(TGF-β1) And Hypoxia On Epithelial-Mesenchymal Transition (EMT)and Stem Characteristics In Pancreatic Cancer Cell Line

AIM To investigate the effect of transforming growth factor-β1(TGF-β1) andhypoxia, in vitro, on epithelial-mesenchymal transition and stem characteristics inpancreatic cancer cell line PANC-1.Methods Human pancreatic cancer cell line PANC-1was incubated with10ng/mlTGF-β1and physical hypoxia (1%O2) for different period of time, separately.Western blot was used to detect the protein expression levels of E-cadherin,vimentin, HIF-1alpha, CD133and OCT-4. The mRNA level of E-cadherin,vimentin, CD133as while as OCT-4was detected with Real-time fluorescentquantitative PCR.The percentage of CD133+cells was measured by flow cytometry.Results Transforming growth factor β1and hypoxia had induced the pancreaticcancer cell line PANC-1, in vitro, from the epithelial cell morphology intomesenchymal cell morphology.The protein level of Vimentin and CD133in PANC-1cells was up-regulatedsignificantly, after treated with10ng/ml TGF-β1for12h,24h,36h,48h. measured byWesten blot. Meanwhile, the level of E-cadherin and OCT-4was down-regulatedsignificantly (p <0.05). The mRNA level of vimentin and CD133was upregulated,and mRNA level of E-cadherin and OCT4was downregulated detecting withReal-time fluorescent quantitative PCR (p <0.05). When PANC-1cells were treatedwith TGF-β1in10ng/ml for12h,24h,36h,48h, the percentage of CD133+cells were10.64%,34.87%,21.12%, and28.33%, respectively. There was significant differentbetween control group and TGF–β1groups (p <0.05). The protein level of Vimentin and CD133in PANC-1cells was up-regulatedsignificantly, after treated with Hypoxia (1%O2) for2h,4h,6h and12h, measured byWesten blot. Meanwhile, the protein level of E-cadherin and OCT-4wasdown-regulated significantly (p <0.05). The mRNA level of vimentin and CD133was upregulated, and mRNA level of E-cadherin and OCT4was downregulateddetecting with Real-time fluorescent quantitative PCR (p <0.05). When PANC-1cellswere treated with1%O2for2h,4h,6h,12h,the percentage of CD133+cells were3.46%,3.46%,3.38%and1.69%respectively. There was no significant differentbetween control group and hypoxia groups (p>0.05).Conclusion The epithelial-mesenchymal transition (EMT) of pancreatic cancer cellline PANC-1could be induced by transforming growth factor β1and hypoxia in vitro,which was accompanied with the increase of pancreatic cancer stem cell surfacemolecule CD133and the reduced of OCT4.