Has_Circ_0002490 Circular RNA: A Potential Novel Biomarker for Lung Cancer

Background: Lung cancer (LC) is ranked as a leading cause of cancer-related death worldwide. However, there are still few reliable screening biomarkers for daily clinical practice in LC. Circular RNAs (circRNAs) have been suggested as valuable diagnostic biomarkers in various cancers. In this study, the expression and diagnostic potential of several circRNAs for LC were explored. Methods: Seventy-two pairs of LC tissues and adjacent normal lung tissues were collected to measure the relative expression level of circRNAs using quantitative reverse transcription-polymerase chain reaction. In addition, the relationships between circRNAs and the clinicopathological features of LC patients were analyzed. Furthermore, the sensitivities and specificities of the circRNAs were evaluated by receiver operating characteristic (ROC) analysis. Results: The expression levels of has_circ_0002490, has_circ_0087357, has_circ_0004891, has_circ_0074368, and has_circ_0000896 were downregulated in LC tissues compared with adjacent normal lung tissues. The lower levels of has_circ_0002490, has_circ_0087357, has_circ_0004891, and has_circ_0000896 were significantly correlated with advanced disease stages. The area under the ROC curves of has_circ_0002490, has_circ_0087357, has_circ_0074368, has_circ_0004891, and has_circ_0000896 were 0.833, 0.793, 0.773, 0.730, and 0.645, respectively. Conclusions: Has_circ_0002490, has_circ_0087357, has_circ_0074368, has_circ_0004891, and has_circ_0000896 are capable of distinguishing LC tissues from normal lung tissues. Besides, the biggest area under the ROC curve value of has_circ_000249 suggests it appears to be a better diagnosis marker for LC patients.