Creatine kinase has been utilized as a diagnostic marker for Duchenne muscular dystrophy (DMD), but it correlates less well with the DMD pathological progression. In this study, we hypothesized that muscle-specific microRNAs (miR-1, -133, and -206) in serum may be useful for monitoring the DMD pathological progression, and explored the possibility of these miRNAs as potential non-invasive biomarkers for the disease. By using real-time quantitative reverse transcription-polymerase chain reaction in a randomized and controlled trial, we detected that miR-1, -133, and -206 were significantly overexpressed in the serum of 39 children with DMD (up to 3.20 AE 1.20, 2 ÀDDCt ): almost 2-to 4-fold enriched in comparison to samples from the healthy controls (less than 1.15 AE 0.34, 2 ÀDDCt ). To determine whether these miRNAs were related to the clinical features of children with DMD, we analyzed the associations compared to creatine kinase. There were very good inverse correlations between the levels of these miRNAs, especially miR-206, and functional performances: high levels corresponded to low muscle strength, muscle function, and quality of life. Moreover, by receiver operating characteristic curves analyses, we revealed that these miRNAs, especially miR-206, were able to discriminate DMD from controls. Thus, miR-206 and other muscle-specific miRNAs in serum are useful for monitoring the DMD pathological progression, and hence as potential non-invasive biomarkers for the disease.

BackgroundThe Pediatric Quality of Life InventoryTM (PedsQLTM) is a widely used instrument to measure pediatric health-related quality of life (HRQOL) in children aged 2 to 18 years. The current study aimed to evaluate the reliability and validity of the Chinese version of the PedsQLTM 3.0 Neuromuscular Module in children with Duchenne muscular dystrophy (DMD).MethodsThe PedsQLTM 3.0 Neuromuscular Module was translated into Chinese following PedsQLTM Measurement Model Translation Methodology. The Chinese version scale was administered to 56 children with DMD and their parents, and the psychometric properties were evaluated.ResultsThe missing value percentages for each item of the Chinese version scale ranged from 0.00% to 0.54%. Internal consistency reliability approached or exceeded the minimum reliability standard of α = 0.7 (child α = 0.81, parent α = 0.86). Test-retest reliability was satisfactory, with intraclass correlation coefficients (ICCs) of 0.66 for children and 0.88 for parents (P < 0.01). Correlation coefficients between iteims and their hypothesized subscales were higher than those with other subscales (P < 0.05). The subscale of “About My/My Child’s Neuromuscular Disease” significantly related to mobility and stair climbing status (Child t = 2.21, Parent t = 2.83, P < 0.05). The inter-correlations among the Chinese version of the PedsQLTM 3.0 Neuromuscular Module and the PedsQLTM 4.0 Generic Core Scales had medium to large effect sizes (P < 0.05). The child self-report scores were in moderate agreement with the parent proxy-report scores (ICC = 0.51, P < 0.05).ConclusionsThe Chinese version of the PedsQLTM 3.0 Neuromuscular Module has acceptable psychometric properties. It is a reliable measure of disease-specific HRQOL in Chinese children with DMD.