Purpose: To mine differentially expressed microRNAs (miRs) in lung adenocarcinoma (LUAD) via The Cancer Genome Atlas (TCGA).
Methods: The transcriptome and pathological data of LUAD patients were downloaded from TCGA. The differentially expressed genes were screened using "edgeR" package in R and analyzed by univariate and multivariate Cox regressions. The expression and clinic value of serum miR-548v in 50 patients with LUAD (study group) and 50 healthy individuals (control group) was detected by the quantitative real time polymerase chain reaction (qRT-PCR), and the diagnostic value of miR-548v in LUAD was analyzed by the receiver operating characteristic (ROC) curve.
Results: A total of 233 differentially expressed genes were found, of which 115 were highly expressed and 118 were lowly expressed. Multivariate Cox regression showed that hsa-mir-142 and hsa-mir-548v were independent prognostic factors for patients with LUAD. The study group showed significantly higher serum miR-548v expression than the control group (p<0.001). miR-548v was related to TNM staging, lymph node metastasis, and tumor size of patients (p<0.05). The area under the curve (AUC) of miR-548v in diagnosing LUAD was 0.960, and that in determining TNM staging, lymph node metastasis and tumor size was 0.829, 0.851 and 0.881 respectively.
Conclusion: Differential expression of miR-548v predicts poor prognosis of patients with LUAD and is closely related to TNM staging, lymph node metastasis and tumor size. Therefore, it is expected to be a potential diagnostic and prognostic marker for LUAD.