Low plasma miR-25 expression is a favorite prognosis factor in non-small cell lung cancer

OBJECTIVE: Circulating microRNAs (miRNAs) are promising biomarkers for the diagnosis and prognosis prediction of cancer. In the study, we aimed to investigate the potential clinical significance of the plasma miR-25 in non-small cell lung carcinoma (NSCLC). PATIENTS AND METHODS: We first compared the miRNAs expression pattern between NSCLC tissues and adjacent normal tissues then. bioinformatic analysis of the downstream targets of miR-25 was performed. The diagnostic and prognostic value of the plasma miR-25 in NSCLC was then evaluated. RESULTS: The expression level of miR-25 was increased in NSCLC tissues compared to the adjacent normal tissues. In addition, bioinformatic analysis of the downstream-targeted genes of miR-25 revealed that many gene ontology functions and pathways were associated with cancer progression. The levels of plasma miR-25 were significantly upregulated in NSCLC patients compared to normal controls. In addition, the plasma miR-25 levels were especially higher in NSCLC patients with positive lymph node metastasis, poorly differentiation or advanced clinical stage. Subsequently, we found that the plasma miR-25 expression levels were dramatically decreased in 45 NSCLC patients after receiving surgical treatment. The receiver operating characteristic (ROC) curve analysis indicated that the plasma miR-25 exhibited high diagnostic sensitivity and specificity to discriminate NSCLC cases from healthy subjects. More interestingly, the combination of the plasma miR-25 and carcinoembryonic antigen (CEA) could effectively enhance the accuracy for distinguishing NSCLC patients from normal controls. Moreover, the plasma miR-25 overexpression was closely correlated with aggressive clinical characteristics and poor survival. Finally, the plasma miR-25 was identified as an independent prognostic marker for the overall survival of NSCLC. CONCLUSIONS: Collectively, our findings demonstrated that the plasma miR-25 might serve as a novel promising biomarker in the diagnosis and prognosis prediction of NSCLC.