Background:The majority of lung cancer cases are non-small cell lung cancer (NSCLC). MicroRNAs (miRNAs) are small non-coding molecules that control target gene(s) expression. Aims: Identification of circulating levels of miRNA-21, 126, 513a, and 98 in NSCLC and assessment of their diagnostic and predictive values. Material and Methods: In this study, the levels of miRNA-21, 126, 513a, and 98 were evaluated in 19 NSCLC patients and 11 healthy individuals. miRNAs were extracted from patients and healthy control whole blood samples and cDNA was synthesized with the specific primers for each miRNA, real-time quantitative polymerase chain reaction (RT-qPCR) was used to assay the expression pattern of miRNAs. Results:The circulating levels of miRNA-21, 126, and 513a were significantly up-regulated in NSCLC patients as compared to the healthy subjects. Of interest, the circulating levels of these miRNAs were about twice higher in stage IV patients than stage III patients. miRNA-513a showed the highest diagnostic accuracy (AUC = 0.942, specificity = 100, and sensitivity = 85.7) and sensitivity was improved when in combination with miRNA-21 (AUC = 0.929, specificity = 90.91, and sensitivity = 92.8). All studied miRNAs showed clear changes during the treatment of NSCLC patients with the platinum regimen. Conclusions: miRNA-21, 126, and 513a may be considered as candidate diagnostic circulating biomarkers in NSCLC as well as a potential predictive biomarkers for the response to the platinum regimen. miRNA-513a showed the highest diagnostic accuracy for distinguishing NSCLC patients from healthy controls.

No abstract