Down-regulated miR-495 can target programmed cell death 10 in ankylosing spondylitis.

BACKGROUND

MicroRNAs (miRNAs) play crucial roles in regulating eukaryotic gene expression. Recent studies indicated that aberrantly expressed miRNAs are involved in the pathogenesis of ankylosing spondylitis (AS). Indeed, hsa-miR-495-3p (miR-495) has been reported as an anti-oncogene in different cancers. However, the role of miR-495 in AS is still unknown.

METHODS

In this study, quantitative real-time polymerase chain reaction (PCR) was used to detect the expression of miR-495 in the peripheral blood mononuclear cells (PBMCs), whole blood, and serum of patients with AS. Bisulfite-specific PCR sequencing and methylated DNA immunoprecipitation were used to detect the methylation in the promoter region of miR-495. To determine the influence of miR-495 expression on the target gene, programmed cell death 10 (PDCD10), dual luciferase reporter assays together with an adenoviral vector containing the miR-495 locus were used. Receiver operating characteristic (ROC) curves were used to evaluate the efficacy of miR-495 as a diagnostic biomarker of AS. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes pathway analysis, and western blotting were used to explore the potential role of miR-495 in AS pathogenesis and the mechanism by which it facilitates AS pathogenesis.

RESULTS

miR-495 is down-regulated and the promoter region of miR-495 is highly methylated in AS. The expression of miR-495 is negatively associated with PDCD10 expression in both patients with AS and healthy controls. Further experiments showed that PDCD10 can be targeted by miR-495. The ROC curves of miR-495 suggested that it is a very specific and sensitive biomarker for AS diagnosis. Bioinformatics analysis and signal pathway studies indicated that miR-495 can down-regulate β-catenin and transforming growth factor-β1.

CONCLUSIONS

Our studies indicated that down-regulation of miR-495 can be used as a potential molecular marker for the diagnosis and treatment of AS, thus providing new insights into the role of miRNAs in AS pathology.