Establishment of FGFR4 over-expression cell line and analysis of its biological activity

Objective: To construct the fibroblast growth factor receptor 4 (FGFR4) over-expression cell line and investigate the effects of FGFR4 on cell proliferation and mechanism of FGFR4-related protein activation so as to provide a molecular model for studying anti-tumor drug candidate targeting on FGFR4. Methods: HEK293 cells were transfected with FGFR4-pcDNA plasmid. Then G418-resistant clones of HEK293 cells were obtained under G418 selection. The expression level of FGFR4 was confirmed by immunoblot and immunofluorescence. Cell proliferation rate was measured using cell counting assay. Flow cytometry analysis was performed to explore the effects of FGFR4 on HEK293 cell cycle. ERK1/2 and p-ERK1/2 expression levels were confirmed by immunoblot. Results: FGFR4 promoted the proliferation of HEK293 cells as compared with native cells under the same culture condition. Cell phase of G₀/G₁ was depressed by FGFR4 activation. The FGFR4 proteins elicited constitutive phosphorylation of ERK1/2, leading to the activation of the mitogen-activated MAPK. Conclusion: We have successfully constructed the over-expression FGFR4 cell line, which lays an experimental foundation for screening anti-tumor drug candidate targeting on FGFR4.