Analysis Of LncRNAs In Lung Adenocarcinoma Based On TCGA Database

Objective In this study,LncRNAs differentially expressed in lung adenocarcinoma tissues and adjacent tissues were screened and analyzed from the Cancer Genome Atlas(TCGA)database.The purpose of this study was to analyze Long non-coding RNA(LncRNAs)related to lung adenocarcinoma and lay a foundation for further study of the biological function of LncRNAs with significantly increased differential expression multiple in lung adenocarcinoma tissues.Meanwhile,LncRNAs related to the prognosis of lung adenocarcinoma were screened to analyze the influence of LncRNAs expression on survival of lung adenocarcinoma.Methods(1)The data of LncRNAs from 535 lung adenocarcinoma tissues and 59 adjacent lung adenocarcinoma tissues were screened from TCGA database,and the clinical data of patients with lung adenocarcinoma were analyzed by edger package of R language.The screening criteria were corrected P < 0.01 and differential expression multiple > 2(FDR < 0.01 and | logFC | > 2)as LncRNAs with statistical significance,and according to the difference.The differential expression of LncRNAs in lung adenocarcinoma tissues was obtained by the logarithmic analysis of the multiple of heterologous expression.(2)Using the survival data of lung adenocarcinoma patients from the differential LncRNAs combined with TCGA database,survival package was used for univariate COX regression analysis,and LncRNAs associated with mortality risk were obtained according to the standard analysis of P < 0.05.(3)In order to reduce over-fitting,the glmnet package and survival package were used for lasso regression analysis,and the minimum cross-validation error was selected as the best reference value to screen more accurate LncRNAs related to death risk.(4)The LncRNAs screened above were used to calculate the hazard ratio(HR),95% confidence interval and P value of each LncRNAs by using survival package,and then selected statistically significant prognostic LncRNAs according to P < 0.05.At the same time,the forest map was drawn using survminer package,and the prognostic LncRNAs could be visually seen.(5)The statistical significance of LncRNAs was analyzed,Kaplan-Meiersurvival curve was drawn,and the effect of high and low expression of each LncRNAs on survival rate was analyzed.Results(1)A total of 1657 LncRNAs were differentially expressed in 535 lung adenocarcinoma tissues and 59 adjacent tissues selected from the TCGA database,of which 1472 were up-regulated and 185 were down-regulated.(2)Univariate COX regression analysis was performed on 1657 differentially expressed LncRNAs,and 86 LncRNAs related to death risk were screened according to P < 0.05 standard.(3)Lasso regression analysis was performed to further compress target death risk-related LncRNAs(P < 0.05),and 48 more accurate LncRNAs related to death risk were screened.(4)Multivariate COX regression analysis was performed on 48 LncRNAs associated with mortality risk(P < 0.05).A total of 11 LncRNAs associated with prognosis were obtained with statistical significance.(5)11 LncRNAs related to prognosis were analyzed by survival package,and the Kaplan-Meier survival curve of each LncRNAs was drawn.It can be seen intuitively that there was no significant difference between the high and low expression of the same LncRNAs in the survival analysis of lung adenocarcinoma patients.The Kaplan-Meier survival curve indicated no significant difference.Conclusions(1)PRKCA-AS1,AC104823.1,AP000542.2,LINC01929,CCAT1,AC090164.2,AP000317.2,AC106874.1,AC106729.1,AP002892.2 and AC004801.5 are prognostic LncRNAs.(2)According to Kaplan-Meier survival curve analysis,each LncRNA related to prognosis was obtained.The expression level of LncRNA had no significant effect on the survival rate of patients.