Tumor-Derived Exosomal miR-620 as a Diagnostic Biomarker in Non-Small-Cell Lung Cancer

BACKGROUND: Evidence has suggested the functional role of exosomal miRNAs in cancer diagnosis. This study aimed to determine whether the serum exosomal biomarkers can improve the diagnosis of patients with non-small-cell lung cancer (NSCLC). MATERIALS AND METHODS: The exosomes were extracted from the serum of NSCLC patients (n = 235) and healthy donors (n = 231) using ultracentrifugation and then were evaluated by using transmission electron microscopy, qNano, and western blotting. The serum exosomal miRNA expression was validated using qPCR. RESULTS: Exosomal miR-620 was significantly reduced in NSCLC and early-stage NSCLC patients (P < 0.0001) when compared to that of healthy controls, with an area under the curve (AUC) of 0.728 and 0.707, respectively. Exosomal miR-620 expression showed an association with drinking (P=0.008) and distant metastasis (P=0.037). Additionally, the downregulated exosomal miR-620 showed association with chemotherapeutic effect (P=0.044). CONCLUSION: These findings suggest the serum exosomal miR-620 as a promising diagnostic and prognostic noninvasive biomarker in NSCLC patients.