Identification of miRNAs as non-invasive biomarkers for early diagnosis of lung cancers.

Current clinical diagnostic methods lack the specificity in detecting lung cancer patients. The issue is particularly critical for stage I and II patients. Considerable evidence showed microRNA plays a very important role in lung carcinogenesis. Here, we identified a panel of 41 miRNAs significantly elevated in patients with lung cancer, of which eight miRNAs were further validated in an independent sample cohort. Classification analysis using the panel of eight miRNAs generated a discriminatory power of 93.3 % sensitivity and 93.8 % specificity in separating non-small-cell lung cancer (NSCLC) patients from normal controls, indicating the miRNAs have a potential clinical utility in discriminating NSCLC. Interestingly, miR-1244 was found significantly elevated in the serum samples of lung cancer patients, and the test characteristics of the single miRNA were area under the curve (AUC) of 0.832 in NSCLC vs healthy controls, and 0.861 in NSCLC vs patients with unidentified pulmonary nodules. This is the first study showing serum miR-1244 could be a biomarker to screen lung cancer patients from the high-risk population.