Plasma circulating microRNA-944 and microRNA-3662 as potential histologic type-specific early lung cancer biomarkers.

Altered expression of microRNAs (miRNAs) is associated with the development and invasion of cancers by regulating post-transcriptionally gene function. Possibility of detection of miRNA expression in patients' plasma or serum makes them valuable biomarkers of different neoplasms. In the present study, we investigated the potential role of miR-944 and miR-3662 expression analysis as novel lung cancer biomarkers and their lung tumor specificity in plasma samples of 90 patients with lung cancer and 85 healthy individuals using quantitative reverse transcription-polymerase chain reaction analysis. Expression of miR-944 and miR-3662 was upregulated in patients with lung cancer in comparison with healthy individuals. Receiver operating curve analysis has presented diagnostic power of analysis of both miRNA expressions for detection of patients with I and II stages of non-small cell lung cancer with area under the curve (AUC) of 0.881. Moreover, miR-944 has shown diagnostic accuracy for operable squamous cell carcinoma detection (AUC = 0.982), whereas miR-3662 has shown the diagnostic accuracy for operable adenocarcinoma (AUC = 0.926). Higher stage of lung cancer correlated with higher miRNA expressions. Our results suggest that the profile of studied miRNAs could be further evaluated and considered as potential lung cancer biomarkers.