IFT80 Improves Invasion Ability In Gastric Cancer Cell Line Via Ift80/p75NGFR/MMP9 Signaling

Objective:To investigate the effects of IFT80(Intraflagellar transport 80)on proliferation,apoptosis and invasion of gastric cancer cells SGC-7901 and MKN-45,and the overexpression of IFT80 up-regulated the nerve growth factor receptor p75 NGFR to increase the expression of MMP9 to promote gastric cancer metastasis.Methods:The expression of IFT80 in 48 clinical gastric cancer tissues was detected by immunohistochemistry.We established SGC-7901 and MKN-45 gastric cancer cell lines that stably overexpressed IFT80.The human gastric cancer cell lines SGC-7901 and MKN-45 were transfected with the control plasmid and IFT80 plasmid,respectively,as verified by Western blot and quantitative reverse transcription-PCR.Overexpression of IFT80 in SGC-7901 cells transfected for 48 h by immunofluorescence assay.FCM was used to detect apoptotic rate of cells.The human gastric cancer cell lines SGC-7901 and MKN-45 were transfected with the control plasmid and the IFT80 plasmid,respectively,and the proliferation ability of the cells was examined by CCK-8.For further verification,we designed three groups,the control group,the IFT80 overexpression group,and the IFT80 overexpression plus inhibitor PD90780 group,after transfecting the three groups with the control plasmid and IFT80 plasmid for 48 h,we detected the expression of p75 NGFR in the three groups by Western blot,qRT-PCR and immunofluorescence.After gastric cancer transfected with control plasmid and IFT80 plasmid for 48 h,the invasion ability of IFT80 on SGC-7901 and MKN-45 cells was examined by the Matrigel invasion assay.Gastric cancer cells transfected with different plasmids for 48 h,the expression of MMP9 were detected by Western blot,quantitative reverse transcription-PCR and immunofluorescence.Results:1.IFT80 is highly expressed in clinical gastric cancer.Besides,overexpression of IFT80 in the gastric cancer cell lines,led to lengthening cilia.2.Overexpression of IFT80 significantly improved proliferation and invasion,but inhibited apoptosis,in gastric cancer cells.3.We further found that overexpression of IFT80 increased p75 NGFR and MMP9 mRNA and protein expression.4.PD90780,the p75 NGFR antagonist,inhibits the increased invasion ability resulting from overexpression IFT80 in SGC-7901 and MKN-45 gastric cancer cells,and the protein expression of MMP9 was also decreased.Conclusion:1.The high expression of IFT80 protein in human gastric cancer tissues may play an important role in gastric cancer process.2.IFT80 overexpression may induces invasion of gastric cancer SGC-7901 and MKN-45 cells by up-regulating the expression of MMP9 and p75 NGFR protein.3.After the addition of the antagonist of p75NGFR(PD90780),the invasive ability of gastric cells is weakened,these results suggested that the reduction in MMP9 protein expression and inhibition of the metastatic ability of gastric cancer cells was at least partially mediated by the down regulation of p75 NGFR.It is further demonstrated that IFT80 improves invasion ability in gastric cancer cell line via ift80/p75NGFR/MMP9 signaling.