Long intergenic noncoding RNA LINC00173 as a potential serum biomarker for diagnosis of non-small-cell lung cancer

Abstract

BACKGROUND: Long intergenic non-coding RNA (lincRNA) belongs to a special type of RNA that is unable to encode proteins but has been proved to play a role in gene regulation and differentially expressed in various malignant tumors. OBJECTIVE: In this study, we aimed to identify whether lincRNA LINC00173 was differentially expressed in non-small-cell lung cancer (NSCLC) and whether it could serve as a potential diagnostic biomarker. METHODS: The quantification real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the expression of LINC00173 in serum and cultured cells. For large sample analysis, the lncRNA expression matrix in TCGA database were generated via R software. To evaluate the diagnostic performance of serum LINC00173, the receiver operating characteristic (ROC) curve was used. RESULTS: The qRT-PCR analysis showed that the serum LINC00173 expression level in 108 NSCLC patients was higher than that in 91 healthy donors and 55 patients with benign pulmonary disease (BPD). And the area under the curve (AUC) of serum LINC00173 was 0.809 for the diagnosis of NSCLC (95% CI: 0.750–0.868, p< 0.001), 0.670 for BPD (95% CI: 0.584–0.756, P< 0.001), and 0.730 for small-cell lung cancer (SCLC, 95% CI: 0.636–0.825, P< 0.001). Besides, we established a diagnostic model of combined detection of LINC00173, CEA and Cyfra21-1, and found that combined detection of these indicators significantly improved the diagnostic efficiency. Analysis of the Clinicopathological parameters showed that high LINC00173 expression was correlated with histological typing of tumor, tumor metastasis and serum Cyfra21-1 levels. In addition, serum LINC00173 expression decreased in patients who received chemotherapy and rebound in recurrent NSCLC patients. CONCLUSION: Serum LINC00173 may prove to be a potential non-invasive auxiliary diagnostic biomarker for NSCLC patients.