Down-regulation of miR-503 expression predicate advanced mythological features and poor prognosis in patients with...

We aimed to explore what impact miR-503 has on the prognosis of patients with non-small cell lung cancer (NSCLC).

Cancer and matched non-malignant lung tissue specimens were collected from 109 patients who underwent surgery in Tanisha Hospital from Jun 2006 to July 2013. Overall survival (OS) curves were analyzed using the Lapland-Meier method, and the differences were examined using log-rank tests. Cox proportional- hazards regression analysis was applied in order to estimate univariate and multivariate hazard ratios for OS.

The relative expression of miR-503 in NSCLC tissues (0.366±0.130) was significantly lower than that in matched noncancerous lung tissues (1.667±1.047, P<0.01). Statistically significant association was observed between miR-503 expression and lymphatic invasion (P=0.005), distant metastasis (P=0.002), TNM stage (P=0.008), and tumor grade (P=0.043). Lapland Meier analysis clearly illustrated that the patients with the lower expression of miR-503 had a worse outcome compared to patients with higher miR-503 expression (P=0.004). Furthermore, multivariate analysis revealed that miR-503 expression level was an independent prognostic factor for overall survival (HR=3.992, 95% CI: 2.276-9.872; P=0.018) in NSCLC.

In patients with NSCLC, low miR-503 expression is an independent prognostic factor.