Serum miR-19a expression correlates with worse prognosis of patients with non-small cell lung cancer.

The aim of this study was to investigate the expression levels of miR-19a in non-small cell lung cancer (NSCLC) tissue and serum, and to clarify the relationships of serum miR-19a expression with clinical factors and prognosis of NSCLC patients. Expression levels of miR-19a in 25 paired NSCLC, paracancerous tissues and serum, and sera from 103 controls and 201 NSCLC patients were respectively detected using real-time quantitative PCR. Compared with the paracancerous tissue, miR-19a was overexpressed in NSCLC tissue (P = 0.006), and there was a strong correlation between expression levels of miR-19 in 25 paired sera and tissues (P = 0.001). Serum miR-19a expression in NSCLC patients was significantly upregulated compared with those in healthy individuals (P = 0.001). High serum miR-19a expression was significantly correlated with TNM stage and lymph node metastasis (P = 0.004 and 0.017, respectively). Survival analysis revealed that overall survival rate of patients with high serum miR-19a expression was significantly worse than those of patients with low serum miR-19a expression (hazard ratio = 1.438, 95% confidence interval 1.007-2.052, P = 0.046). High serum miR-19a expression may be an independent poor prognostic factor for survival in NSCLC patients.