MiR-34a, miR-21 and miR-23a as potential biomarkers for coronary artery disease: a pilot microarray study and confirmation in a 32 patient cohort

Abstract

The aim of this study was to investigate the expression of circulating microRNAs (miRNAs) in apolipoprotein E (apoE) knockout mice (apoE−/−) and to validate the role of these miRNAs in human coronary artery disease (CAD). Pooled plasma from 10 apoE−/− mice and 10 healthy C57BL/6 (B6) mice was used to perform the microarray analysis. The results showed that miR-34a, miR-21, miR-23a, miR-30a and miR-106b were differentially expressed in apoE−/− mice, and these expression changes were confirmed by real-time quantitative reverse-transcription PCR. Then, miR-34a, miR-21, miR-23a, miR-30a and miR-106b were detected in the plasma of 32 patients with CAD and of 20 healthy controls. Only miR-34a, miR-21 and miR-23a were significantly differentially expressed in the plasma of CAD patients (all P<0.01). In conclusion, miR-34a, miR-21 and miR-23a were elevated in CAD patients, which means that these miRNAs might serve as biomarkers of CAD development and progression. The levels of three microRNA (miRNA) molecules in blood may serve as useful biomarkers for coronary artery disease (CAD). MicroRNAs are small non-coding RNAs that regulate gene expression by binding to messenger RNA and inhibiting its ability to make proteins. The human genome encodes over 1000 miRNAs and many are implicated in various diseases. Shanshun Luo and colleagues at Harbin Medical University in China used microarray analysis to detect elevated levels of several miRNAs in a mouse model of CAD associated with high cholesterol levels. They found elevated levels of three of these miRNAs in the blood of 32 patients with CAD. They suggest that the identified miRNAs could be used as markers to screen patients for CAD and to monitor its progression and the effectiveness of treatment.