Background: The aim of the study was to explore the expression level of miRNA-30 expression in patients with non-small cell lung cancer (NCLC) and analyze its correlation with clinicopathological features and prognosis.
Methods: Preoperative serum samples and paracancerous tumor-free tissues of 108 patients with NSCLC treated in our hospital as well as serum samples of 108 healthy subjects were collected from April 2015 to May 2018. The expression levels of miRNA-30 in tissue samples were detected by in situ hybridization and that of miRNA-30 mRNA in serum samples by real-time quantitative PCR (RT-qPCR). The difference in miRNA-30 expression in tumor-free tissues of NSCLC patients and NSCLC tissues of each stage was measured. The miRNA-30 mRNA levels in NSCLC patients was compared with those in healthy subjects. All subjects were divided into low-expression group (< mean) and high expression group (≥ mean) with the mean value of miRNA-30 levels being the critical value. The relationship between miRNA-30 levels and clinicopathological parameters (gender, age, lymph node metastasis, tumor size, TNM stage, degree of infiltration, and differentiation) was analyzed, and the prognosis of different serum miRNA-30 levels was compared based to follow-up data.
Results: The expression level of miRNA-30 in cancer tissues and serum of NSCLD patients was significantly lower (p < 0.05, respectively). The results of ROC curve analysis showed that the area under the curve for the diagnosis of NSCLC using miRNA-30 was 0.802 (95% CI: 0.742 to 0.861, p < 0.001), with the diagnostic threshold being 0.798, sensitivity and specificity being 75.9% and 76.0%, respectively. Serum miRNA-30 levels in NSCLC patients were not associated with gender, age, and depth of infiltration (p > 0.05), but correlated with lymph node metastasis, tumor size, TNM stage, and degree of differentiation (p < 0.05). The median overall survival of the miRNA-30 low expression group was 23.0 months, which was shorter than the 36.0 months of high expression group, and the difference was statistically significant (p < 0.05).
Conclusions: miRNA-30 is lowly expressed in NSCLC patients and participates in the development of NSCLC. Moreover, NSCLC patients with low expression show poor prognosis. Thus, miRNA-30 features potential as a marker for NSCLC screening and prognosis prediction.