MiRNA analysis in Thoracic Aortic aneurysms

Thoracic Aortic Aneurysm (TAA) is characterized by the dilation and degradation of the aorta and is fatal if not diagnosed and treated appropriately. There are no specific clinical symptoms, so better knowledge of the physiopathology of TAAs and their underlying genetic mechanisms is needed to improve diagnosis and therapy. MiRNAs regulate gene expression post-transcriptionally and are known to be involved in cerebrovascular disease. The current study aimed to identify differentially expressed miRNAs in patients with TAAs and determine whether their predicted target genes could be associated with this condition. Nanostring assays identified miRNAs in plasma and tissue samples from four TAA patients. RT-PCR validated the expression levels of these miRNAs in a further 22 plasma samples. Three, hsa-miR140-5p, hsa-miR-191-5p and hsa-miR-214-3p showed significant expression level differences between plasma samples collected pre- and post-surgically from each patient. Analyses of the predicted target gene controlled by these miRNAs revealed nine genes whose expression was investigated in the same 22 plasma samples. The gene expression levels were inversely correlated with the expression of their respective miRNAs. From these, CCND2, CRKL, HEY1, MTMR4, NFIA and PPP1CB, showed fold-change differences >1.5 between the two plasma samples. An in-depth literature search and Cytoscape software three genes; MTMR4, NFIA and PPP1CB, showed a possible association with the TGF-β signalling pathway. It is suggested that the three miRNAs detected together with their target genes could play a role in the TGF-β signalling pathway and thus be involved in TAA pathogenesis. Nanostring assays of miRNAs in plasma and tissue samples from four TAA patients.