Prognostic significance of NDRG2 combined with EGFR patients with lung adenocarcinoma

Abstract

Background: N-myc downstream-regulated gene 2 (NDRG2) plays a substantial role in lung adenocarcinoma (LUAD). Epidermal growth factor receptor (EGFR) mutation could significantly improve prognosis in patients with LUAD. In this study, we aimed to elucidate the prognostic value of NDRG2/EGFR in patients with LUAD. Methods: Immunohistochemistry, Western blotting, and reverse transcription-polymerase chain reaction (RT-PCR) were conducted to detect the expression levels of NDRG2 protein. Association between NDRG2/EGFR expression and clinicopathological characteristics of patients with LUAD was examined as well. Serum level of carcinoembryonic antigen (CEA) was tested prior to treatment of patients with LUAD. Patients’ overall survival was assessed by Kaplan–Meier method. Multivariate Cox regression analysis was carried out to investigate the effects of patients’ demographic characteristics on OS. Results: The expression level of NDRG2 was significantly decreased in patients with LUAD. The expression level of NDRG2 was positively correlated with levels of CEA and EGFR. Advanced stages were significantly associated with low expression level of NDRG2. We found that patients in NDRG2-high/EGFR(+) group had the best outcome, while patients in NDRG2-low/EGFR(-) group had the worst. Meanwhile, Cox regression analysis showed that NDRG2-low/EGFR(+), NDRG2-high/EGFR(+), and vascular invasion were independent prognostic factors of LUAD. Conclusion: The significant prognostic value of NDRG2/EGFR should be highly considered in patients with LUAD.