MicroRNA-134 as a potential plasma biomarker for the diagnosis of acute pulmonary embolism

Background: Acute pulmonary embolism (APE) remains a diagnostic challenge due to a variable clinical presentation and the lack of a reliable screening tool. MicroRNAs (miRNAs) regulate gene expression in a wide range of pathophysiologic processes. Circulating miRNAs are emerging biomarkers in heart failure, type 2 diabetes and other disease states; however, using plasma miRNAs as biomarkers for the diagnosis of APE is still unknown.Methods: Thirty-two APE patients, 32 healthy controls, and 22 non-APE patients (reported dyspnea, chest pain, or cough) were enrolled in this study. The TaqMan miRNA microarray was used to identify dysregulated miRNAs in the plasma of APE patients. The TaqMan-based miRNA quantitative real-time reverse transcription polymerase chain reactions were used to validate the dysregulated miRNAs. The receiver-operator characteristic (ROC) curve analysis was conducted to evaluate the diagnostic accuracy of the miRNA identified as the candidate biomarker.Results: Plasma miRNA-134 (miR-134) level was significantly higher in the APE patients than in the healthy controls or non-APE patients. The ROC curve showed that plasma miR-134 was a specific diagnostic predictor of APE with an area under the curve of 0.833 (95% confidence interval, 0.737 to 0.929; P <0.001).Conclusions: Our findings indicated that plasma miR-134 could be an important biomarker for the diagnosis of APE. Because of this finding, large-scale investigations are urgently needed to pave the way from basic research to clinical utilization.