Diagnosic Significance Of Plasma MiRNA-20a And MiRNA-210 Expression For Lung Cancer

Objective:The purpose of this study was to probe the feasibility and clinical value of plasma miRNA-20a and miRNA-210 in the diagnosis of lung cancer.Methods:1.Research objects:Taking 58 lung cancer patients and 46 benign disease patients as the research objects.2.Primer designs and syntheses:Primers of miRNA-20a,miRNA-210 and U6 gene were designed and synthesized by Rui Bo biological company.3.Research Method:The plasma was separated from peripheral blood samples of the research objects,and then total RNA was extracted from the plasma,followed by the reverse transcription reaction for cDNA synthesis.After that,qRT-PCR reaction was performed to detect the Ct values of plasma miRNA-20a and miRNA-210.The formula(objective gene Ct value-reference gene Ct values = ?Ct values)was used to obtain ? Ct values.Finally,the relative levels of plasma miRNA-20a and miRNA-210 expression were calculated using the 2-??Ct method.4.Statistical analyses:Statistical analyses were performed using SPSS19.0.The Wilcoxon rankings were used to compare the paired groups,a P-value<0.05 was considered statistical significant.Receiver-operating characteristic(ROC)curves were constructed and area under the ROC curve(AUC)were analyzed to define the optimal cut-off points which were used to calculate the sensitivity,specificity,positive predictive value and negative predictive value for diagnosing lung cancer.Results:1.The expression levels of plasma miRNA-20a and miRNA-210 in patients with lung cancer were significantly elevated than those with benign lung disease(P<0.05).2.There was no significant correlation between expression of plasma miRNA-20a and clinicopathological characteristics in lung cancer patients,whereas the expression levels of plasma miRNA-210 was significantly associated with tumor histological types,differential degree and clinical stages(P=0.008,P=0.041 and P=0.016,respectively)in patients with lung cancer.3.The AUCs of plasma miRNA-20a and miRNA-210 were 0.883(95%CI,0.821-0.946)and 0.824(95%CI,0.745-0.904),which were higher than those of CEA(0.656,95%CI,0.551-0.761)and Cyfra21-1(0.754,95%CI,0.658-0.847),respectively.The sensitivity(77.6%and 75.9%)and accuracy(81.7%and 77.9%)of the two sRNAs for diagnosing lung cancer were higher than those of CEA(44.8%and 62.5%)and Cyfra21-1(56.9%and 72.1%).And the sensitivity was increased when analeses were done by combining miRNA-20a with miRNA-210.4.The combination of plasma miRNA-20a and miRNA-210 with CEA or Cyfra21-1 further raised the sensitivity in diagnosis of lung cancer,despite slightly decreased specificity.5.Using kappa identity test analyses,the results showed that the kappa values of miRNA-20a(42.763,p<0.001)and miRNA-210(32.534,p<0.001)were significantly higher than those of CEA(10.383,p =0.001)and Cyfra21-1(26.005,p<0.001).Conclusions:1.Plasma miRNA-20a and miRNA-210 may serve as a biomarker in the diagnosis of lung cancer.2.Comparing with serum CEA and Cyfra21-1,the diagnostic performance of plasma miRNA-20a and miRNA-210 as tumor markers for lung cancer was better.