Identification and Functional Analysis of Serum Specific miRNAs in Recurrent Aphthous Stomatitis Patients with Excess-heat or Yin-deficiency

Background:To identity key miRNAs as signatures for recurrent aphthous stomatitis(RAS)with Excess-heat or Yin-deficiency bymiRNA microarrays. Method: Serum samples were collected from patients meeting the RAS diagnostic criteria of excess-heat oryin-deficiencysyndrome and healthy individuals. CoremicroRNAs (miRNAs) were then identified under miRNA microarray analyses. Target prediction and bioinformatic analyses were carried out andgene-pathway-networks werevisualized to better understand the relationship between differentgenes and pathways.Result:(1) 90 individuals meeting the inclusion criteria were collected in this study, of which 30 were normal control, 30 were patients of excess-heat syndrome and the rest were patients ofyin-deficiency syndrome. Among them, 9 miRNAs werescreened out in excess-heat syndrome group, with 1 upregulated and 8 downregulated. And four randommiRNAs(hsa-miR-20b-5p, hsa-miR-122-5p, hsa-miR-483-5p and hsa-miR-3197) were validatedby real-time PCR method. 14 miRNAs werescreened out in yin-deficiency syndrome group(7 upregulated and 7 downregulated). And hsa-miR-17-5p, hsa-miR-106-5p and hsa-miR-20b-5p were validated. (2)A total of 4776 target genes were identified for the validated 9 miRNAs in excess-heat syndrome group.These targets were enriched inGO categories including nervous system development, homophilic cell adhesion via plasma membrane adhesion molecules, and calcium ion binding and KEGG pathway such as proteoglycans in cancer, P13K-AKT signaling pathway and Calcium signaling pathway. 10172 target genes were identified for the validated 14 miRNAs in yin-deficiency syndrome group. The enrichedGO categories included protein binding, positive regulation of transcription from RNA polymerase II promoter and membrane andenrichedKEGG pathway included pathways in cancer, MAPK signaling pathway and Ras signaling pathway.Conclusion:Hsa-miR-20b-5p in patients with RAS could act as the novel target for syndromeclassification of the disease. It is upregulated in RAS patients with excess-heat syndrome while downregulated in patients with yin-deficiency syndrome. The PI3K-Akt signaling pathway and MAPK signaling pathway and related target genes may provide new insights into the molecular mechanisms of RAS with excess-heat syndrome or yin-deficiency syndrome, respectively.