Microarray expression profile analysis of long non-coding RNAs in thoracic aortic aneurysm.

Thoracic aortic aneurysm (TAA) is a highly lethal vascular disease. Long non-coding RNAs (lncRNAs) are newly discovered as a regulator of protein genes and play critical roles in cardiovascular physio-pathological processes. However, there were a few studies looking at lncRNAs in TAA. In this study, we profiled differential expression of lncRNAs between TAA (TAA group, N = 6) and normal thoracic aorta (control group, n = 6) by third-generation lncRNA microarray. We identified 1352 up-regulated and 1624 down-regulated lncRNAs with differential expression (log fold-change > 2.0, p < 0.01). Through nearby protein-coding gene associated with extracellular matrix (ECM) metabolism and vascular smooth muscle cell (VSMC) apoptosis, 12 up-regulated and 9 down-regulated lncRNAs were selected for further analysis. By calculating phastCons score of base, we identified 8 candidate lncRNAs (4 up-regulated and 4 down-regulated) with high conservation across species. By tissue specificity analysis, we found that 5 lncRNAs (HIF1A-AS1, RP11-465L10.10, LOC100506472, CTD-2184D3.5 and RP-399O19.5) were highly expressed in aortic tissues, suggested that they may be closely associated with TAA. Among them, 2 lncRNAs (RP11-465L10.10 and CTD-2184D3.5) with higher specificity in aorta (p < 0.01) were analyzed by bioinformatics. Further catRAPID analysis revealed a strong RNA-protein interaction between RP11-465L10.10 and myeloid zinc finger gene 1 (MZF1), a transcription factor of MMP9. However, no intense RNA-protein interactions were observed between CTD-2184D3.5 and transcript factors of MAPK6. In conclusions, our study showed differential expression profiles of lncRNAs in TAA and revealed the interaction between certain lncRNAs and coding genes. These data provides insights into new biomarker and therapeutic targets for TAA.