Expression And Study On The Mechanism Of FOXO4 And FOSB In Glioma

Objective: In this study,the surgical specimens of glioma patients admitted to Neurosurgery Department of Yijishan hospital(the First Affiliated Hospital of Wannan Medical College)and Neurosurgery Department of the Eastern Theater General Hospital were taken as the research objects.The purpose of this study was to investigate the expression of transcription factor human forkhead box protein O4(FOXO4)and g0/g1 conversion regulatory protein 3(FOSB)in glioma.Furthermore,by regulating FOXO4 and FOSB in glioma cells,the effects of FOXO4 and FOSB on proliferation and migration phenotype of malignant cells were recorded,and the role of FOXO4 and FOSB in the occurrence and development of glioma was searched,so as to accumulate more relevant basic data for clinical treatment and understanding of glioma.Methods: Firstly,the tumor tissue samples of clinical glioma patients,including low-grade glioma samples and high-grade glioma samples,were collected,and the normal brain tissue samples were taken as the control group.Western Blot and immunohistochemical staining were used to detect the expression of FOXO4 and FOSB in different grades of gliomas and normal brain tissues,and the difference was statistically analyzed.Then,it was further verified in the cell line.The expression of FOXO4 and FOSB in normal human astrocytes(HA)and five glioblastoma(GBM)cell lines(U251,U118,U87,T98 G,A172)were detected by quantitative real-time PCR(qRT-PCR)and Western Blot.We selected two GBM cell lines with strong difference between GBM cell lines and HA cell line from five cell lines.We regulated the expression of FOXO4 and FOSB,transfected over expression or knockdown lentivirus,established stable cell lines and detected tumor phenotype.Western Blot was used to verify the expression difference of FOXO4 and FOSB in the transfected two GBM celllines.The tumor phenotype was detected by scratch test,plate cloning,cell counting kit-8(CCK-8),Transwell method,and subcutaneous implantation in nude mice.The effect of FOXO4 or FOSB on the phenotype of glioma cell line was detected.Results: The results of immunohistochemistry and Western Blot showed that the expression of FOXO4 in gliomas was lower than that in normal brain tissues,and the expression of FOXO4 in high-grade gliomas was lower than that in low-grade gliomas(P < 0.05).In further cell line experiments,FOXO4 expression in GBM cell lines(U87and U251)was lower than that in normal HA cell line(P < 0.05).FOXO4 over expressed stable cell line significantly inhibited the proliferation,migration and invasion of GBM cells.In CCK-8 proliferation experiment,FOXO4 increased the apoptosis of GBM cell lines,FOXO4 also reduced the temozolomide resistance of GBM cell lines,and inhibited the growth of GBM cells transplanted subcutaneously in nude mice(P < 0.05).The expression of FOSB in gliomas,especially in high-grade gliomas,was significantly higher than that in normal brain tissue(P < 0.05).After deletion of FOSB gene,FOSB decreased,caspase 3 expression increased,that is,GBM cell apoptosis increased(P < 0.05).Plate cloning and CCK-8 experiments showed that the proliferation ability of U87 and U251 GBM cell lines decreased after FOSB gene knockdown,while Transwell experiment showed that the migration ability of glioblastoma cell lines decreased after FOSB gene knockdown(P < 0.05).Conclusion: The expression of FOXO4 in glioma was lower than that in normal brain tissue,and FOXO4 has the activity of inhibiting glioma.However,FOSB was highly expressed in glioma tissues,and the proliferation and migration ability of glioma cells decreased after down-regulation of FOSB.It is suggested that FOSB may promote the expansion and migration of glioma.The expression of FOXO4 and FOSB in glioma can provide experimental data for understanding and treatment of glioma,and lay a foundation for targeted therapy of glioma.