Effect of the interaction between MiR-200b-3p and DNMT3A on cartilage cells of osteoarthritis patients.

The aim of this research is to explore the effect of miR-200b-3p targeting DNMT3A on the proliferation and apoptosis of osteoarthritis (OA) cartilage cells. Quantitative RT-PCR was performed to analyse the expression of miR-200b-3p, DNMT3A, MMP1, MMP3, MMP9, MMP13 and COL II in normal and OA cartilage tissues. The dual-luciferase reporter assay and Western blot assay were conducted to confirm the targeting relationship between miR-200b-3p and DNMT3A. We also constructed eukaryotic expression vector to overexpress miR-200b-3p and DNMT3A. We detected the expression level of MMPs and COL II in stable transfected cartilage cells using RT-PCR and Western blot. Cell proliferation and apoptosis were evaluated using the MTS, pellet culture and Hoechst 33342 staining method. Finally, we explored the effect of miR-200b-3p targeting DNMT3A on the proliferation and apoptosis of OA cartilage cells. The results of RT-PCR indicated that both miR-200b-3p and COL II were down-regulated in OA cartilage tissues, while the expression of DNMT3A and MMPs was up-regulated in OA cartilage tissues. The expressions of DNMT3A, MMPs and COL II detected by Western blot showed the same trend of the results of RT-PCR. The dual-luciferase reporter assay and Western blot assay confirmed the targeting relationship between miR-200b-3p and DNMT3A. In overexpressed miR-200b-3p cartilage cells, DNMT3A and MMPs were significantly down-regulated, COL II was significantly up-regulated, cell viability was enhanced and apoptosis rate was decreased (P < 0.05). In overexpressed DNM3T cartilage cells, MMPs were significantly up-regulated, COL II was significantly down-regulated, cell viability was weakened and apoptosis rate was increased (P < 0.05). MiR-200b-3p inhibited the secretion of MMPs, promoted the synthesis of COL II and enhanced the growth and proliferation of OA cartilage cells through inhibiting the expression of DNMT3A.

Systemic bioinformatics analysis of recurrent aphthous stomatitis gene expression profiles.

Recurrent aphthous stomatitis (RAS) represents the most common chronic oral diseases with the prevalence ranges from 5% to 25% for different populations. Its pathogenesis remains poorly understood, which limits the development of effective drugs and treatment methods. In this study, we conducted systemic bioinformatics analysis of gene expression profiles from the Gene Expression Omnibus (GEO) to identify potential drug targets for RAS. We firstly downloaded the gene microarray datasets with the accession number of GSE37265 from GEO and performed robust multi-array (RMA) normalization with affy R programming package. Secondly, differential expression genes (DEGs) in RAS samples compared with control samples were identified based on limma package. Enriched gene ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways of DEGs were obtained through the Database for Annotation, Visualization and Integrated Discovery (DAVID). Finally, protein-protein interaction (PPI) network was constructed based on the combination of HPRD and BioGrid databases. What's more, we identified modules of PPI network through MCODE plugin of Cytoscape for the purpose of screening of valuable targets. As a result, 915 genes were found to be significantly differential expression in RAS samples and biological processes related to immune and inflammatory response were significantly enriched in those genes. Network and module analysis identified FBXO6, ITGA4, VCAM1 and etc as valuable therapeutic targets for RAS. Finally, FBXO6, ITGA4, and VCAM1 were further confirmed by real time RT-PCR and western blot. This study should be helpful for the research and treatment of RAS.