Circulating Microrna-339-5p and -21 in Plasma As an Early Detection Predictors of Lung Adenocarcinoma

BACKGROUND:Many studies have shown that differentially expressed miRs in body fluids can serve as biomarkers in non-invasive detection of the cancers. However, the clinical significance of plasma miRs in the diagnosis of lung adenocarcinoma (LA) is still not clear. Therefore, we examined the LA-specific miRs in plasma, which could be utilized to diagnosis and monitor LA in routine clinical practice.METHODS:Twenty-eight LA cases and twenty-eight healthy controls were recruited to our study. MiRs differential expression in plasma was measured by miRNA Microarray assay and revalidated by using qRT-PCR based absolute quantification methods The diagnostic power of circulating miRs in LA was evaluated using the receiver operating characteristics (ROC) curves and the area under the ROC curves (AUC).RESULTS:Tumor tissues and plasma levels of miR-339-5p were significantly down-regulated in LA patients compared with those in the control group, whereas the levels of miR-21 in LA patients were significantly higher than control group. ROC analysis showed that miR-339-5p and miR-21 could distinguish LA patients from healthy controls with high AUC (0.900 and 0.880, respectively), sensitivity (0.821 and 0.821, respectively) and specificity (0.929 and 0.964, respectively). Importantly, the combination of miR-339-5p and miR-21 markedly improved AUC (0.963), sensitivity (0.929) and specificity (0.929).CONCLUSION:Plasma miR-339-5p or miR-21 could serve as a potential biomarker for diagnosis of LA, however, the combination of miR-339-5p and miR-21 was more efficient for LA detection.