Circulating CUDR, LSINCT-5 and PTENP1 long noncoding RNAs in sera distinguish patients with gastric cancer from healthy controls

The examination of circulating nucleic acids (CNAs) is an emerging noninvasive diagnostic technique. However, it is unclear if serum long noncoding RNAs (lncRNAs) represent a novel marker to detect gastric cancer (GC). In this study, we measured 39 candidate cancer-associated lncRNAs by reverse transcription and quantitative polymerase chain reaction (RT-qPCR) in sera from 110 patients with GC, 106 age- and sex-matched healthy subjects and 15 patients with gastric peptic ulcer, markers were validated and assessed by RT-qPCR. The correlation of the expression levels of the candidate serum lncRNAs with clinical parameters of GC patients was performed. A three-lncRNA signature, including CUDR, LSINCT-5 and PTENP1, was identified that may be potential diagnostic marker for GC. The areas under the receiver operating characteristic (ROC) curve for this serum three-lncRNA signature were 0.920 and 0.829 for the two sets of serum samples. Moreover, a risk model for the serum three-lncRNA signature demonstrated that healthy samples can be distinguished from early GC samples. Three-lncRNA signature in serum was identified as diagnostic marker for GC. This work may facilitate the detection of GC and serve as the basis for further studies of the clinical value of serum lncRNAs in maintaining surveillance and forecasting prognosis. What's new? Certain long noncoding RNAs (lncRNAs) may be involved in oncogenesis or tumor suppression, raising questions about their potential service as cancer biomarkers. The authors of the present study systematically assessed the diagnostic value of serum-detectable lncRNAs for gastric cancer (GC) patients. Reverse transcription, quantitative PCR resulted in the identification of a GC-associated three-lncRNA signature centering on CUDR, LSINCT-5 and PTENP1. The three-lncRNA signature successfully distinguished between early-stage GC patients and healthy subjects. The findings warrant further investigation of the clinical utility of serum lncRNAs in the detection of early-stage GC.