miR-29c-3p is an Effective Biomarker of Abdominal Aortic Aneurysm in Patients Undergoing Elective Surgery.

BACKGROUND

Abdominal aortic aneurysm (AAA) is usually asymptomatic and mostly diagnosed incidentally. Aortic dilatation progresses along with the wall weakening and eventually leads to a life-threatening rupture. Currently, there are no effective screening biomarkers for AAA. MicroRNAs, a class of small noncoding RNA molecules, offer great potential as biomarkers because of their stability in the bloodstream and expression profile specific for different diseases.

OBJECTIVE

To assess the circulating miR-29c-3p as a potential biomarker of AAA and to elucidate the biological functions of miR-29c-3p in terms of pathogenesis of aneurysms.

METHODS

Two groups of patients scheduled for elective surgery were studied: 52 patients with AAA, and 51 patients with peripheral artery disease who served as a control group (matched by age and gender). Serum miRNA was measured for circulating miR-29c-3p using quantitative real-time PCR. Functional tests of miR-29c-3p impact on the targeted transcripts were studied using its mimic or inhibitor and a cell culture of endothelial cells.

RESULTS

Serum miR-29c-3p was significantly elevated in AAA patients as compared with controls (RQ=8.73) and correlated with the diameter of the aneurysm. No association between well-known risk factors and level of circulating miR-29c-3p was found using a logistic regression. In vitro study revealed that miR-29c-3p suppressed transcripts of ELN, COL4A1, PTEN and VEGFA.

CONCLUSION

The results suggest that elevated miR-29c-3p is a potential serum biomarker for AAA. Causal involvement of miR-29c-3p in pathogenesis of the disease was found in human vascular endothelial cells, which extracellular matrix synthesis and integrity maintenance was inhibited.