High circulating miR‐18a, miR‐20a, and miR‐92a expression correlates with poor prognosis in patients with non‐small cell lung cancer

The purpose of this study was to assess the predictive value of angiogenic miRNAs for disease‐free survival (DFS) and overall survival (OS) of patients with non‐small cell lung cancer (NSCLC). In total, 196 patients with NSCLC (tumor lymph nodes metastasis (TNM) stage I–III) were enrolled and peripheral blood samples were collected. Total RNA was extracted from blood samples, and the relative expression levels of candidate miRNAs were evaluated by real time‐polymerase chain reaction (RT‐PCR). The median follow‐up period was 56.7 months, and the final follow‐up date was in August 2016. The median DFS of all patients was 30.0 (14.0–49.0) months, whereas the median OS was 41.5 (23.0–58.0) months. Furthermore, the 5‐year DFS and OS rates were 11.3% and 32.3%, respectively. Kaplan–Meier (K–M) curves showed that high plasma miR‐18a (P < 0.001), miR‐20a (P < 0.001), miR‐92a (P < 0.001), miR‐126 (P < 0.001), miR‐210 (P = 0.003), and miR‐19a (P = 0.027) expressions levels correlated with a worse DFS. Moreover, patients with high plasma miR‐18a, miR‐20a, miR‐92a, miR‐210, and miR‐126 expression levels had a shorter OS than patients with low expression levels of these miRNAs (all P <= 0.001). Furthermore, multivariate Cox regression analyses revealed that high plasma expression levels of miR‐18a, miR‐20a, and miR‐92a as well as lymphatic node metastasis (all P < 0.001) were independent risk factors for both DFS and OS in patients with NSCLC. Thus, the circulating miR‐18a, miR‐20a, and miR‐92a levels may serve as novel and promising prognostic biomarkers in patients with NSCLC.