Abstract: Background and purpose: Neuropilin-1 (NRP1), a vascular endothelial growth factor (VEGF) receptor, plays an important role in tumor angiogenesis and tumor cell migration. The purpose of this study was to determine the correlation between NRP1 expression and sensitivity to first-line platinum-based chemotherapy in patients with advanced non-small cell lung cancer (NSCLC), and between NRP1 expression and survival. Methods: NRP1 expression in tumor tissues of 104 advanced NSCLC patients treated with first-line platinum-based regimen was detected by immunohistochemisty. A chi-square test and logistic regression model were used to analyze the relationship between NRP1 expression and the chemotherapy response rate. Kaplan-Meier and Cox proportional hazard regression models were used to analyze the effect of NRP1 expression on patient survival. Results: Among the 104 patients, 56 (53.8%) had high expression of NRP1. High expression of NRP1 was not related to age, gender, histological type, degree of differentiation, performance status, and chemotherapy regimen. The chemotherapy response rate was significantly higher in patients with low NRP1 expression than in patients with high expression (43.8% vs 23.2%, P=0.026). The low NRP1 expression was significantly associated with longer progression-free survival (4.6 months vs 3.0 months, P=0.001 for log-rank test, χ²=11.273) and overall survival (11.5 months vs 9.2 months, P=0.000 for log-rank test, χ²=14.392) as compared with high NRP1 expression. Multivariate analysis showed that high expression of NRP1 was an independent predictor for the chemotherapy response rate and overall survival in patients with advanced NSCLC. Conclusion: NRP1 expression is associated with response rate and survival in advanced NSCLC patients treated with first-line platinum-based chemotherapy. NRP1 expression may be a potential biomarker for predicting chemosensitivity and prognosis in patients with advanced NSCLC.

Key words: Non-small cell lung cancer, Neuropilin-1, Chemosensitivity, Prognosis