Extracellular microRNAs in bronchoalveolar lavage samples from patients with lung diseases as predictors for lung cancer.

Abstract Objective The detection of tumor-associated microRNA expression in bronchial lavage (BL) samples of lung cancer patients could improve the non-invasive tumor diagnostic. Methods The profile of extracellular microRNAs in bronchial lavage was evaluated using three pools for lung cancer group (malignant) and three pools for non-cancerous group (benign) of 10 patients each. To confirm the results for the selected microRNAs in a qRT-PCR the BL of 30 different lung cancer and non-cancerous patients was used. We examined total-RNA from cell-free supernatant of BL samples. For normalization we added exogenous cel-miR 39. Results Using microRNA arrays we found a panel of eight microRNAs (hsa-miR 19b-1, 1285, 1289, 1303, 217, 29a-5p, 548-3p, 650) that were differentially expressed between the lung cancer and the non-cancerous group. Further investigation by qPCR revealed five microRNAs (U6 snRNA, hsa-miR 1285, 1303, 29a-5p, 650) that were significantly up-regulated in patients with lung cancer. Conclusions In bronchial lavage samples the five microRNAs identified in this study have a diagnostic potential for use as noninvasive biomarkers in lung cancer.