Clinicopathological Significance of Neuropilin 1 Expression in Gastric Cancer: A Meta-Analysis

Background Neuropilin 1 (NRP1) is involved in tumorigenesis, development, invasion, and metastasis by promoting angiogenesis of tumors. The study is aimed at evaluating the correlation between the expression of NRP1 protein and clinicopathological features of gastric cancer by meta-analysis. Methods The published studies were searched in databases including CNKI, Wanfang, Chongqing VIP, Web of Science, and PubMed online. Clinical case studies were included to compare the correlation between NRP1 protein expression and clinicopathological characteristics of gastric cancer. The quality of the included literatures was evaluated by NOS scale. Meta-analysis was performed by Stata software to calculate the odds ratio (OR) and 95% confidence interval (CI). Results A total of 12 studies were included in this analysis, involving 1,225 patients with gastric cancer. The analysis indicated that the expression of NRP1 protein in gastric cancer tissues was lower in the group of early stage versus advanced stage (OR = 0.128, 95%CI = 0.059 - 0.277, P ≤ 0.001), tumor size less than 5 cm versus more than 5 cm (OR = 0.443, 95%CI = 0.310 - 0.632, P ≤ 0.001), TNM stage I-II group versus stage III-IV patients (OR = 0.736, 95%CI = 0.589 - 0.919, P = 0.007), well to medium differentiation group versus poor differentiation group (OR = 0.735, 95%CI = 0.632 - 0.854, P ≤ 0.001), and nonlymph node metastasis group versus lymph node metastasis group (OR = 0.667, 95%CI = 0.522 - 0.854, P ≤ 0.001). The expression of NRP1 protein in gastric cancer was not related to gender, age, and Lauren's classification. Conclusion The expression of NRP1 protein in gastric cancer is closely correlated to clinical stage, tumor size, TNM stage, differentiation, and lymph node metastasis.