Effect of epidermal growth factor(EGF) on the biological characteristics of a cell line expressing EGF receptor on its membrane

Objective To study the effect of EGF on the biological characters of a cell line(CHO-EGFR-GFP1) expressing EGFR on its membrane.Methods Trypan blue exclusion assays were used to test cell viability and proliferation after EGF treatment at different concentrations.Cell cycle and apoptosis were determined with flow cytometry after the cells were treated with EGF at different concentrations for 48h or 100 ng/mL EGF for different interval and stained with piopidium iodide.The apoptosis was also analyzed with Hoechst 33258 staining.EGFR expression levels were detected with flow cytometry by evaluating the mean fluorescence intensity(MFI) of GFP(green fluorescent protein).Results EGF at low concentrations promoted proliferation,while EGF at high concentrations induced loss of adhesion,cell cycle arrest,apoptosis,and inhibition of proliferation.The effects of EGF on cell proliferation correlated well with the expression levels of EGFR.EGF at high concentrations induced both EGFR expression and apoptosis in a dose-dependent manner.Conclusion EGF treatments at different concentrations have different effects on the biological characteristics of CHO-EGFR-GFP1.The loss of adhesion caused by EGF treatment at high concentrations might be one of mechanisms promoting the metastasis of tumor cells.