MicroRNA from the blood extracellular microvesicles for minimally invasive diagnostics of lung cancer

BACKGROUND: Asymptomatic development and untimely diagnostics of lung cancer are the main reasons of high mortality caused by this disease. The development of tests based on “fluid biopsy”, which analyze circulating nucleic acids in blood, including the microRNA (miRNA) derived from the microvesicles, can be implemented as an effective screening test for lung cancer assuring the timely detection of the disease. AIM: To analyze the relative expression of 17 miRNAs in the microvesicles fraction from blood plasma samples from patients with non-small-cell lung cancer (NSCLC) and healthy donors. METHODS: The blood plasma microvesicles were isolated by aggregation-precipitation. miRNA was then isolated from the obtained blood microvesicles fraction using the glass fiber filters. Using the method of reverse transcription polymerаse chain reaction, an evaluation was carried out for the diagnostic efficiency of previously proposed miRNA pairs. This analysis was also used to select the most effective diagnostic pairs and panels. RESULTS: The obtained data have confirmed the diagnostic efficiency of four miRNA pairs (-31/-125b; -133b/-374a; -133b/-425; -133b/-222). The sensitivity and the specificity of distinguishing NSCLC patients from donors were 79% and 100%, respectively. Further analysis using paired normalization, compiling the regression models and multiple sample generations yielded three independent minimal panels of miRNA pairs, capable of diagnosing NSCLC with 100% accuracy: (1) -19b/-425, -125b/-378a, -205/-660; (2) -324/-374a, -30e/-92a, -125b/-378a; (3) -324/-374a, -125b/-378a, -205/-660. CONCLUSION: The diagnostic performance of the proposed miRNA panel across independent cohorts, along with the observed inter-cohort variability, supports its promising potential for NSCLC screening test development. These data demonstrate the necessity to identify additional multi-purpose miRNA markers and to validate the panel in further independent patient groups. Such research is essential to establish a reliable and timely miRNA-based screening tool for NSCLC.