Circulating LncRNA XLOC_009167 Serves As a Diagnostic Biomarker to Predict Lung Cancer

Background: Long noncoding RNAs (lncRNAs) have been proven to be involved in carcinogenesis and to be released into peripheral blood. Our objective was to develop a circulating lncRNA as a novel biomarker to predict lung cancer.

Methods: We analyzed the lncRNA expression profile in lung cancer patients by lncRNA array and identified lncRNA XLOC_009167 as a circulating biomarker using qRT-PCR in whole blood of lung cancer patients. The diagnostic value of was analyzed by area under curve (AUC) and the receiver operating characteristic (ROC) test.

Results: LncRNA XLOC_009167 was screened as a candidate biomarker for lung cancer and was up-regulated in both lung cancer tissues and cell lines. Notably, lncRNA XLOC_009167 in whole blood of lung cancer patients was highly expressed as compared with that in healthy controls or in patients with pneumonia. The values of AUC of lung cancer vs. healthy controls, and that of lung cancer vs. pneumonia were 0.7398 (95%CI = 0.6493 to 0.8303) and 0.7005 (95%CI = 0.5771 to 0.8240), respectively. Intriguingly, the ROC showed lncRNA XLOC_009167 was a better diagnostic potential compared to the traditional biomarkers (CYFR21-1, NSE and CA72-4), and the circulating lncRNA XLOC_009167 was found to be stable in whole blood under different conditions.

Conclusions: LncRNA XLOC_009167 could serve as a novel diagnostic biomarker to distinguish lung cancer from benign lung disease and healthy controls.