Decreased Expression of a Novel lncRNA FAM181A-AS1 is Associated with Poor Prognosis and Immune Infiltration in Lung Adenocarcinoma

BACKGROUND: There is no clear information regarding the role of FAM181A antisense RNA 1 (FAM181A-AS1) in lung adenocarcinoma (LUAD). We explored the relationship between FAM181A-AS1 and LUAD using bioinformatics analysis and experimental validation in this study. METHODS: Statistics and databases were used to evaluate the relationship between clinical features in LUAD patients and FAM181A-AS1 expression, prognostic factors, regulation network, and immune infiltration of FAM181A-AS1 in function. LUAD cell lines were tested for FAM181A-AS1 expression using qRT-PCR. RESULTS: FAM181A-AS1 showed significantly low expression in LUAD patients. Low FAM181A-AS1 expression predicted a poorer overall survival (OS) (HR: 0.66; 95% CI: 0.49–0.88; P=0.005) and disease specific survival (DSS) (HR: 0.64; 95% CI: 0.44–0.92; P=0.017) of LUAD patients. There was also an independent correlation between low FAM181A-AS1 expression (HR: 0.547; 95% CI: 0.350–0.857; P=0.008) and OS in LUAD patients. The FAM181A-AS1 high-expression phenotype was differentially enriched for M phase, cellular senescence, cell cycle checkpoints, chromatin modifying enzymes, ESR-mediated signaling, DNA repair, G2/M checkpoints, HCMV infection, and DNA double-strand break repair. A correlation was found between the expression of FAM181A-AS1 and immune infiltrating cells. A significant decrease in FAM181A-AS1 expression was observed in LUAD cell lines compared to Beas-2B. CONCLUSION: There was a significant association between low FAM181A-AS1 expression in LUAD patients and poor survival and immune infiltration. The FAM181A-AS1 gene may provide a useful biomarker for LUAD prognosis and immunotherapy response.