Study on role of CDH17 regulating TGF-β autocrine for affecting invasion of gastric cancer cells / 重庆医学

ABSTRACT

Objective To explore the role and possible mechanism of transforming growth factor (TGF)-β autocrine in CDH17 regulating invasion of gastric cancer cells.Methods Construction and transfection of siRNA-CDH17 into MKN-45 gastric cancer cell line to silence the expression of CDH17.Expression of TGF-β and concentrations of TGF-β in supernatants were detected before and after CDH17 silence by immunofluorescence,immunoblotting and ELISA.The autocrine situation of TGF-β was observed.Meanwhile,the activation of TGF-β/Smad3 signaling pathway was also detected by immunoblot.After giving signaling pathway inhibitor,the changes of invasion ability of MKN-45 cells were observed by Transwell invasion experiment.The role of TGF-β autocrine and related signaling pathway activation in CDH17-regulated invasion of gastric cancer cells was evaluated.Results After transfecting siRNA-CDH17 for silencing CDH17 expression in MKN-45 cells,the expression of TGF-β was significantly decreased compared with non-transfection group,its concentration in supernatants was also significantly reduced[(510 ±55)pg/mL vs.(115±20) pg/mL,P<0.01].The immunoblots revealed that phosphorylation level of Smad3 after CDH17 silence was also significantly diminished.However,giving the TGF-β/Smad3 signaling inhibitor SIS3 (10 μmol/L) could also suppress the phosphorylation level of Smad3 when CDH17 was highly expressed,meanwhile silencing CDH17 and inhibiting Smad3 phosphorylation could significantly decrease the invasion of MKN-45 gastric cancer cells (P<0.05).Conclusion CDH17 could participate in the invasion of gastric cancer cells by promoting TGF-β autocrine to activate TGF-β/Smad3 signaling pathway.