Differential expression of microRNAs profile in the peripheral blood of children with drug-resistant epilepsy / 中华实用儿科临床杂志

ABSTRACT

Objective:To study the profile of microRNAs (miRNAs) in the peripheral blood of children with drug-resistant epilepsy, and to find diagnostic biomarkers for early identification of drug-resistant epilepsy in children.Methods:Retrospective study.Five peripheral blood samples were collected from children in drug-resistant epilepsy group (group R), drug-responsive epilepsy group (group F) composed of the children with epilepsy in pediatric neurology clinic of the First Affiliated Hospital of Zhengzhou University from January 2018 to June 2019 and healthy control group (group J) composed of healthy children who underwent physical examination in the children′s health care clinic at the same time for analyzing miRNA profiles by high-throughput sequencing.In addition, peripheral blood samples were collected from children in R′ group (5 cases), F′ group (7 cases) and J′ group (6 cases) similarly for validating expression levels of 11 candidate miRNAs by quantificational real-time polymerase chain reaction (qPCR). Receiver operating characteristic curves (ROC) were plotted to analyze the diagnostic potential of 7 targeted miRNAs in distinguishing children with drug-resistant epilepsy from drug-responsive epilepsy.Target genes of the 7 validated miRNAs were predicted using online databases, which were then analyzed by Kyoto Encyclopedia of Genes and Genomes (KEGG) and gene ontology (GO). Kruskal-Wallis rank sum test was used for comparison among the three groups.Results:High-throughput sequencing found that compared with group F, there were 68 differentially expressed miRNAs in group R, involving 22 up-regulated and 46 down-regulated miRNAs.qPCR results showed that, expression trends of 7 miRNAs (let-7f, miR-99a-5p, miR-99b-5p, and miR-125a-5p, miR-125b-5p, miR-142-5p, miR-100) were consistent with high-throughput sequencing results among the 11 selected miRNAs.ROC analysis found that when the cut-off values of miR-99a-5p, miR-99b-5p, miR-125a-5p, miR-125b-5p, miR-142-5p and miR-100 were greater than 0.56, 1.00, 3.17, 2.24, 2.09 and 0.59, respectively, their area under curve (AUC) (≥0.871), sensitivity (≥80.0%) and specificity (≥85.7%) were relatively high, which were expected to be diagnostic marker for drug-resistant epilepsy in children.Among them, the diagnostic potential of miR-125b-5p was the best.Bioinformatics analysis found that miR-125b-5p was enriched in the regulation of hypoxia inducible factor-1 signaling pathway, insulin signaling pathway, pluripotent stem cell signaling pathway, mitogen-activated protein kinase signaling pathway, sphingomyelin signaling pathway, neurotrophic protein signaling pathway and mammalian target of rapamycin signaling pathway.Conclusions:The miRNA profile in the whole blood of children with drug-resistant epilepsy is significantly different from that in children with drug-responsive epilepsy.miR-125b-5p is expected to be a potential biomarker of drug-resistant epilepsy in children.