Identification Of A Serum Circulating LncRNA Panel For The Diagnosis And Recurrence Prediction Of Bladder Cancer

Objective:Accumulating evidence indicates that dysregulated lncRNAs are involved in tumor genesis and progression.We evaluated the expression level of lncRNAs in bladder cancer(BC)tissue and serum samples,determined lncRNAs that showed statistically differential expression and established the lncRNA-panel for the diagnosis of BC.The diagnostic performance of the lncRNA-panel and the association between lncRNAs and tumor recurrence was also examined.Methods:1.lncRNAs that were previously reported to be dysregulated in BC were selected as candidate lncRNAs.2.The expression level of candidate lncRNAs were evaluated in 80 BCand matched adjacent normal tissues via quantititative real-time PCR(qRT-PCR).After date analysis,we selected lncRNAs that were dysregulated between BC and matched adjacent normal tissues for further evaluation.3.In the training set,we investigated the expression level of selected lncRNAs through qRT-PCR in serum from 52 healthy subjects,68 benign disease and 120 BC patients.We then selected lncRNAs that were significantly dysregulated in healthy vs.BCs and benign disease vs.BCs as potential diagnostic lncRNAs.Those potential diagnostic lncRNAs were used to constructed the diagnostic lncRNA panel for the differentiation between BCs and control group.We also analyzed the correlation of selected lncRNAs expression level between serum samples and corresponding tumor tissue samples by Pearson correlation analysis.4.In the validation set,potential diagnostic lncRNAs were further examined in an independent cohort of 48 healthy subjects,52 benign disease and 100 BC patients and the diagnostic value of the lncRNA panel for BC was also evaluated.In addition,the urine samples were also obtained from these 100control subjects and 100 BC patients for urine cytology.The comparison of the diagnostic performance between urine cytology and lncRNA panel was also performed5.In order to evaluate the relation between potential diagnostic lncRNAs and the recurrence of BC,we followed 100 BC patients including 61 NMIBC and 39 MIBC.In NMIBC and MIBC group,the analysis of survive curves and independent recurrence prediction factor was identified by Kaplan-Meier method and Cox proportional hazard regression model,respectively.Results:1.11 of 13 candidate lncRNAs were significantly dysregulated between BC samples and matched adjacent normal tissues(p<0.01).2.In the training set,three lncRNAs including MEG3,SNHG16,and MALAT1 showed significantly different expression in healthy vs.BCs and benign disease vs.BCs comparisons.MEG3 was significantly down-regulated,and SNHG16 and MALAT1 were significantly up-regulated(all p<0.01).The AUCs of MEG3,SNHG16 and MALAT1 were 0.798,0.687 and 0.640,respectively.By pearson correlation analysis,a significant correlation was observed for MEG3(r = 0.629,p<0.05),SNHG16(r = 0.556,p<0.05)and MALATI(r = 0.401,p<0.05),respectively.3.In the-validation set,the expression level of MEG3,SNHG16 and MALAT1 showed the same dysregulation in healthy vs.BCs and benign disease vs.BCs comparisons.The AUC of the lncRNA panel was 0.828(95%Cl = 0.768-0.877,sensitivity = 82.0%and specificity = 73.0%).The AUCs of the panel for BC patients diagnosed as Ta,T1 and T2-T4 were 0.778,0.805 and 0.880,significantly higher than those of urine cytology,which were 0.548,0.604 and 0.682,respectively(p<0.01).4.By Kaplan-Meier survival analysis,we observed that patients with low MEG3 level had shorter recurrence-free survival(RFS)than patients with high MEG3 level(p =0.028).Multivariate Cox regression analysis showed that MEG3(p = 0.046)and tumor stage(p = 0.041)were independent prognostic factors for the RFS of NMIBC.In MIBC,no independent recurrence prognostic factor was found.Cornclusions:1.The serum MEG3.SNHG16 and MALAT1 have high diagnostic value for BC.2.The serum lncRNA diagnostic panel could serve as a method to diagnose BC and would have considerable clinical value for BC diagnosis especially for early stage.3.The expression level of MEG3 could serve as a recurrence-independent prognostic factor of NMIBC.