We performed an initial screening of miRNA expression using RNA isolated from 20 patients with angiographically documented very early-onset CAD and 20 age- and sex-matched normal controls. For further confirmation, we prospectively examined the miRNAs selected from 40 patients with very early-onset CAD and 40 angiography-normal controls.
A total of 22 overexpressed miRNAs and 22 underexpressed miRNAs were detected in the initial screening. RT-qPCR analysis of the miRNAs obtained from the initial screening revealed that four miRNAs including miR-196-5p, miR-3163-3p, miR-145-3p, and miR-190a-5p exhibited significantly decreased expression in patients compared with that in controls (P<0.05). The areas under the receiver operating characteristic curve for these miRNAs were 0.824 (95% CI, 0.731–0.917; P<0.001), 0.758 (95% CI, 0.651–0.864; P<0.001), 0.753 (95% CI, 0.643–0.863; P<0.001), and 0.782 (95% CI, 0.680–0.884; P<0.001), respectively, in the validation set.
To our knowledge, this is an advanced study to report about four serum miRNAs (miR-196-5p, miR-3163-3p, miR-145-3p, and miR-190a-5p) that could be used as novel biomarkers for the diagnosis of very early-onset CAD.