Kang Lin,1,* Tao Xu,1,* Bang-Shun He,1 Yu-Qin Pan,1 Hui-Ling Sun,1 Hong-Xin Peng,2 Xiu-Xiu Hu,2 Shu-Kui Wang1 1Central Laboratory, Nanjing First Hospital, Nanjing Medical University, 2Medical School, Southeast University, Nanjing, Jiangsu, People’s Republic of China *These authors contributed equally to this work Abstract: Lung cancer is one of the leading causes of cancer death worldwide. Accumulating evidence has indicated that microRNAs (miRNAs) can be proposed as promising diagnostic and prognostic markers for various cancers. The current study analyzed the miRNA expression profiles of 418 lung adenocarcinoma (LUAD) cases obtained from The Cancer Genome Atlas dataset, with the aim to investigate the relationship of miRNAs with progression and prognosis of LUAD. A total of 185 miRNAs were found to be differentially expressed between LUAD tumor tissues and adjacent normal tissues. Among them, 13, 10, 0, and 10 miRNAs were discovered to be associated with pathologic T, N, M, and Stage, respectively. Interestingly, mir-200 family (mir-200a, mir-200b, and mir-429) was shown to play a critical role in the progression of LUAD. In the multivariate Cox regression analysis, mir-1468 (P=0.009), mir-212 (P=0.026), mir-3653 (P=0.012), and mir-31 (P=0.002) were significantly correlated with recurrence-free survival. With regard to overall survival, mir-551b (P=0.011), mir-3653 (P=0.016), and mir-31 (P=0.001) were proven as independent prognostic markers. In summary, this study identified the cancer-specific miRNAs that may predict the progression and prognosis of LUAD. Keywords: microRNA, progression, prognosis, lung adenocarcinoma