Nidogen-1 is a common target of microRNAs MiR-192/215 in the pathogenesis of Hirschsprung's disease.

Recent studies have emphasized the important role of microRNA (miRNA) clusters and common target genes in disease progression. Despite the known involvement of the miR-192/215 family in many human diseases, its biological role in Hirschsprung disease (HSCR) remains undefined. In this study, we explored the role of the miR-192/215 family in the pathogenesis of HSCR. Quantitative real-time PCR and western blotting measured relative expression levels of miRNAs, mRNAs, and proteins in 80 HSCR patients and 77 normal colon tissues. Targets were evaluated by dual-luciferase reporter assays, and the functional effects of miR-192/215 on human 293T and SH-SY5Y cells were detected by the Transwell assay, CCK8 assay and flow cytometry. MiR-192/215 was significantly down-regulated in HSCR tissue samples, and their knockdown inhibited cell migration and proliferation in the human 293T and SH-SY5Y cell lines. Nidogen 1 (NID1) was confirmed as a common target gene of miR-192/215 by dual-luciferase reporter gene assay and its expression was inversely correlated with that of miR-192/215 in tissue samples and cell lines. Silencing of NID1 could rescue the extent of the suppressing effects by miR-192/215 inhibitor. The down-regulation of miR-192/215 may contribute to HSCR development by targeting NID1. We proposed the following cascade for the proposed mechanism of miR-192/215 in the pathogenesis of Hirschsprung disease (HSCR) by targeting Nidogen 1 (NID1). Aberrant expression of miR-192/215 inhibits cell migration and cell proliferation via NID1. We think the miR-192/miR-215/NID1 signaling pathway may play an important role in the pathogenesis of HSCR.

A common polymorphism in pre-miR-146a underlies Hirschsprung disease risk in Han Chinese.

BACKGROUND: Hirschsprung disease (HSCR) is a rare multigenic congenital disorder characterized by the absence of the enteric ganglia. To date, single nucleotide polymorphisms (SNPs) in pre-miRNAs have been confirmed related with some diseases. Thus, we hypothesized that pre-miRNA polymorphisms might contribute to HSCR susceptibility. We investigated whether rs2910164 and rs11614913 of pre-miR-146a and pre-miR-196a2, are associated with HSCR. METHODS: Polymorphisms were genotyped using the Taqman method. Real-time PCR was used for detecting the expression level of miR-146a and its target gene ROBO1 in CC and GG genotypes. RESULTS: Significant differences were found in the genotype distribution of rs2910164 and rs11614913 polymorphism between HSCR cases and controls (p = 0.023 and 0.041, respectively). Furthermore, G allele of rs2910164 might increase the risk of HSCR (OR, 1.54; 95% CI, 1.06-2.23). Moreover, the expression level of miR-146a for homozygote GG was also higher than homozygote CC (p = 0.0193). In contrast, the expression level of its target gene ROBO1 predicted in bioinformatics for homozygote GG was much lower than homozygote CC (p = 0.0096). CONCLUSIONS: Our results showed that the polymorphism rs2910164 in pre-miR-146a might alter the production of mature miR-146a and then down-regulate the target gene ROBO1, which plays an important role in pathogenesis of HSCR.

Down-regulation of miR-206 is associated with Hirschsprung disease and suppresses cell migration and proliferation in cell models.

Hirschsprung disease (HSCR) is a well-known congenital digestive disease that originates due to the developmental disorder of neural crest cells. MiR-206 is kown to have a relationship with digestive malfunctions. Therefore, we investigated whether or not miR-206 was involved in the pathogenesis of HSCR. qRT-PCR and Western blot assays were used to detect the expression levels of miRNA and mRNAs, and proteins in case and control tissue samples and two cell lines (293T and SH-SY5Y). The functions of miR-206 in vitro were measured by transwell assay, CCK8 assay and flow cytometry. Finally, we conducted dual-luciferase reporter assay to verify the connections between miR-206 and the target mRNA SDPR. Down-regulation of miR-206 was found in HSCR case tissue samples compared with controls, which was validated to be connected with the increased level of mRNA and protein of SDPR by qRT-PCR and dual-luciferase reporter assay. Moreover, miR-206 suppressed the cell migration and proliferation and silencing of SDPR could rescue the extent of the suppressing effects by miR-206 inhibitor. The findings suggest that miR-206 may play a significant role in the pathogenesis of HSCR, as well as inhibiting the cell migration and proliferation by targeting SDPR in disease models.