Circulating microRNA signature for the diagnosis of childhood dilated cardiomyopathy

Abstract

Circulating miRNAs are proposed as a biomarker of heart disease. This study evaluated whether circulating miRNAs could be used as a biomarker for childhood dilated cardiomyopathy (CDCM). A total of 28 participants were enrolled in a discovery set, including patients with CDCM (n = 16) and healthy children (n = 12). The cardiac function of patients with CDCM was characterized by echocardiography and serum miRNA profiles of all participants were assessed by miRNA sequencing. After miRNA profiling, we quantitatively confirmed 148 regulated miRNAs in patients with CDCM compared with healthy subjects, and none were downregulated. Validation of candidate miRNAs was assessed by quantitative real-time polymerase chain reaction in other patients with CDCM (n = 30) and healthy controls (n = 16). A unique signature comprising mir-142-5p, mir-143-3p, mir-27b-3p, and mir-126-3p differentiated patients with CDCM from healthy subjects. Importantly, we observed an increase in mir-126-3p or let-7g in parallel with a robust decrease in the ejection fraction in patients with CDCM, which could differentiate heart failure patients from non-heart failure patients with CDCM. Moreover, mir-126-3p and let-7g were significantly negatively associated with the left ventricular ejection fraction. This study shows that a signature of four serum miRNAs may be a potential biomarker for diagnosing CDCM and assessing heart failure.

Conflict of interest statement

The authors declare that they have no competing interests.

Figures

Figure 1

Overview of miRNAs Sequencing Data. (A)Volcano plot of differentially expressed miRNAs between DCM patients and healthy controls. Volcano plot of detectable genome-wide miRNA profiles in differentiating 16 DCM cases and 12 controls. The x-axis shows the log2 foldchange in circulating miRNAs’ expression between DCM cases and controls, while the y-axis shows the −log10 of p value for each miRNA. (B) Heat map of differentially expressed miRNAs between DCM patients and healthy controls. The result of unsupervised hierarchical clustering of circulating miRNAs from DCM patients and healthy control. The color scale shown at the top illustrates the relative expression level of a miRNA, comparing the DCM patients group clusters with the CON group. Red color represents an expression level above mean and green color represents expression lower than the mean.

Figure 2

Quantitative RT-PCR analysis of differentially expressed miRNAs in serum. Comparative analysis of expression levels of (A) let-7f-5p, (B) let-7g-5p (C) let-7i-5p (D) miR-142-5p (D) miR-1425p (E) miR-126-3p (F) miR-143-3p (G) miR-24-5p (H) miR-26a-3p (I) miR-27a-3p (J) miR-27b3p (K) miR-98-5p by quantitative RT-PCR analysis in an validation phase. ****P < 0.0001; ***P, < 0.001; **P < 0.01; *0.01 < P < 0.05.

Figure 3

Receiver operating characteristic(ROC) curve for single circulating miRNA for the diagnosis DCM.

Figure 4

Comparison of miRNAs in DCM patients with different cardiac function. Comparative analysis of expression levels for selected microRNA candidates for DCM EF > 55%, DCM EF ≤ 55% and healthy controls; ****P 

Figure 5

ROC plots of the individual and combined 2 miRNAs differentially expressed between the CDCM patients with heart failure and non-Heart failure.

Figure 6

Linear Regression Analysis of ejection fraction and microRNA in DCM patients. Linear Regression Analysis of EF and MicroRNA in DCM patients.