Circulating Long Non-coding RNAs Act As Potential Novel Biomarkers For Diagnosis And Prognosis Of Non-small Cell Lung Cancer

Objective:Lung cancer is one of the most common malignant tumors all over the world.Non-small cell lung cancer(NSCLC)is the most common pathological type of lung cancer.Currently,the method of diagnosing NSCLC is quite limited,variety of questions occurred,such as the lower sensitivity and specificity of screen methods,the worse compliance of patients.So searching for one rapid noninvasive screen biomarker with high sensitivity and specificity is an urgent work.Recent years,IncRNAs become the focus of biomarker research,as accumulating studies shown that IncRNAs play vital roles in tumor initiation and progression.In the present study,we aimed to evaluate whether serum circulating IncRNAs have the potential value for acting as biomarkers for diagnosis and prognosis of NSCLC.Methods:1.Firstly,NSCLC related dysregulated IncRNAs were obtained by searching literatures in PubMed database using key words "NSCLC"、"IncRNA",and were selected as candidate IncRNAs.2.In screening stage,quantitative real-time PCR(qRT-PCR)was utilized to detect the expression profiles of candidate IncRNAs in NSCLC and corresponding adjacent normal tissues.After statistical analysis,IncRNAs dysregulated between NSCLC and normal tissues were selected for further serum evaluation and then picked the dysregulated IncRNAs in NSCLC serum compared with healthy control serums.Moreover,we enrolled training cohort including 140 NSCLC and 120 healthy controls to evaluate the expression of thus selected IncRNAs in serum samples.At the same time,we measured the expression level of NSCLC related protein tumor markers-CEA,CYFRA21-1,SCCA from NSCLC patients and healthy controls and assessed the diagnose efficiency of each molecule.We next constructed the NSCLC diagnostic panel consisting of the potential IncRNAs and CEA,CYFRA21-1,SCCA based on a logistic regression model.We then analyzed the diagnose efficiency of thisdiagnostic panel.3.In validation stage,we evaluated the expression level of selected IncRNAs in another independent cohort(100 NSCLC patients and 100 healthy controls).Next,we analyzed the diagnostic capability of the serum IncRNA diagnostic panel in this cohort by calculating the area under the ROC curve(AUC).4.100 patients in validation stage were followed up to explore the correlation between IncRNAs and overall survival(OS)rate of NSCLC patients.A Kaplan-Meier survival analysis and Cox proportional hazard regression model were utilized to portray the survival curve and identify independent hazard prognostic factor.Results:1.14 NSCLC-related dysregulated IncRNAs were selected from PubMed database as candidate IncRNAs.2.During screening stage,12 IncRNAs were significantly dysregulated among 14 candidate IncRNAs between NSCLC and matched adjacent normal tissues(p<0.05).2 IncRNAs(SOX2OT and ANRIL)were statistically different between NSCLC and healthy control serum specimens.In training stage,SOX2OT and ANRIL were overexpressed in NSCLC serum samples compared with healthy controls(p<0.01).The AUCs of SOX2OT,ANRIL,CEA,CYFRA21-1 and SCCA was 0.745.0.723.0.631.0.620 and 0.612 respectively.And the AUC of the serum NSCLC diagnostic panel composed of above 5 molecules was 0.853(95%CI:0.804-0.894,sensitivity:77.1%,specificity:79.2%).3.In validation stage,SOX20T and ANRIL were significantly dysregulated in serum samples of NSCLC compared with healthy controls(p<0.01).The AUCs of the serum NSCLC diagnostic panel composed of SOX20T,ANRIL,CEA,CYFRA21-1 and SCCA was 0.883(95%CI:0.830-0.924,sensitivity:91.0%,specificity:70.0%).The AUCs of the 5-molecule diagnostic panel for distinguishing TNM Ⅰ,Ⅱ,Ⅲ stage NSCLC patients were 0.862,0.875 and 0.917,respectively.4.Kaplan-Meier survival analysis indicated that patients with low expressions of SOX20T and ANRIL achieved a higher 5-year OS rate compared with patients with higher expressions of SOX20T and ANRIL(p=0.008,0.017,respectively).Multivariate Cox proportional hazards regression model analysis revealed SOX20T level((p = 0.036)and TNM stage(p = 0.023)were identified as significantly independent prognostic factors.Conclusions:1.The serum IncRNAs were valuable to act as a potential biomarker to diagnose NSCLC from healthy controls.And the constructed panel was of great significance for NSCLC diagnosis at early stage.2.LncRNA SOX2OT could serve as an independent prognostic factor of NSCLC.