Prognosis and functional role of EIF4G1 in lung squamous cell carcinoma

Abstract Purpose To study the functional role and prognosis of EIF4G1 in lung squamous cell carcinoma (LSCC). Methods The clinical relevance of EIF4G1 in LSCC was investigated following detection of the expression levels of EIF4G1 by immunohistochemical staining (IHC). The expression levels of EIF4G1, AKT2, p-AKT, mTOR, cyclin D1 and β-actin were detected by western blot analysis. The cell proliferation and colony formation assays were used to detect the cell proliferative ability; flow-cytometry was used to assess the cell cycle; an invasion assay was used to detect cell invasive ability and the real-time quantitative polymerase chain reaction (Q-PCR) assay was used to assess the expression levels of EIF4G1 and β-actin. The role of EIF4G1 was verified by xenograft models. These experimental methods were employed to assess the functional role of EIF4G1 in LSCC pathogenesis. Results EIF4G1 was overexpressed in LSCC tumor tissues (P < 0.05) compared with the corresponding expression noted in paired adjacent tissues and cells. The expression levels of EIF4G1 were dependent on age (P = 0.002) and clinical stage (I vs II vs III + IV) (P < 0.001). High expression of EIF4G1 (P = 0.008, HR = 2.277, 95% CI = 1.250–4.145) could be used to predict the overall survival of LSCC patients as determined by the Cox’s proportional hazard model. High expression of EIF4G1 exhibited a lower survival (LogRank = 7.167, P = 0.007) in LSCC. Downregulation of EIF4G1 significantly inhibited LSCC proliferation, invasion and cell cycle progression. Conclusion EIF4G1 promotes LSCC cell proliferation and may represent an indicator of prognosis in LSCC.