Dysregulated expression of microRNAs in aqueous humor from intraocular tuberculosis patients

Diagnostic value of microRNAs in active tuberculosis based on quantitative and enrichment analyses

BACKGROUND

Tuberculosis (TB) infection remains a crucial global health challenge, with active tuberculosis (ATB) representing main infection source. MicroRNA (miRNA) has emerged as a potential diagnostic tool in this context. This study aims to identify candidate miRNAs for ATB diagnosis and explore their possible mechanisms.

METHODS

Differentially expressed miRNAs in ATB were summarized in qualitative analysis. The diagnostic values of miRNAs for ATB subtypes were assessed by overall sensitivity, specificity, and area under the curve. Additionally, we conducted enrichment analysis on miRNAs and target genes.

RESULTS

Over 100 differentially expressed miRNAs were identified, with miR-29 family being the most extensively studied. The miR-29 family demonstrated sensitivity, specificity, and area under the curve of 80 %, 80 % and 0.86 respectively for active pulmonary TB (PTB). The differentially expressed miR-29-target genes in PTB were enriched in immune-related pathways.

CONCLUSIONS

The miR-29 family exhibits good diagnostic value for active PTB and shows association with immune process.

Detection of microRNAs expression signatures in vitreous humor of intraocular tuberculosis

BACKGROUND

MicroRNA (miRNA) expression analysis has been shown to provide them as biomarkers in several eye diseases and has a regulatory role in pathogenesis. However, miRNA expression analysis in the vitreous humor (VH) of intraocular tuberculosis (IOTB) is not studied. Thus, we aim to find miRNA expression signatures in the VH of IOTB patients to identify their regulatory role in disease pathogenesis and to find them as potential biomarkers for IOTB.

METHODS AND RESULTS

First, we profiled miRNAs in VH of three IOTB and three Macular hole (MH) samples as controls through small-RNA deep sequencing using Illumina Platform. In-house bioinformatics analysis identified 81 dysregulated miRNAs in IOTB. Further validation in VH of IOTB (n = 15) compared to MH (n = 15) using Real-Time quantitative PCR (RT-qPCR) identified three significantly upregulated miRNAs, hsa-miR-150-5p, hsa-miR-26b-5p, and hsa-miR-21-5p. Based on the miRNA target prediction, functional network analysis, and RT-qPCR analysis of target genes, the three miRNAs downregulating WNT5A, PRKCA, MAP3K7, IL7, TGFB2, IL1A, PRKCB, TNFA, and TP53 genes involving MAPK signaling pathway, PI3K-AKT signaling pathway, WNT signaling pathway, Cell cycle, TGF-beta signaling pathway, Long-term potentiation, and Sphingolipid signaling pathways, have a potential role in disease pathogenesis. The ROC analysis of RT-qPCR data showed that hsa-miR-150-5p with AUC = 0.715, hsa-miR-21-5p with AUC = 0.789, and hsa-miR-26b-5p with AUC = 0.738; however, the combination of hsa-miR-21-5p and hsa-miR-26b-5p with AUC = 0.796 could serve as a potential biomarker for IOTB.

CONCLUSIONS

This study provides the first report on miRNA expression signatures detected in VH for IOTB pathogenesis and also provides a potential biomarker for IOTB.

Differential methylation of microRNA encoding genes may contribute to high myopia

Introduction: High myopia (HM), an eye disorder with a refractive error ≤-6.0 diopters, has multifactorial etiology with environmental and genetic factors involved. Recent studies confirm the impact of alterations in DNA methylation and microRNAs (miRNAs) on myopia. Here, we studied the combined aspects evaluating to the role of methylation of miRNA encoding genes in HM. Materials and Methods: From the genome-wide DNA methylation data of 18 Polish children with HM and 18 matched controls, we retrieved differentially methylated CG dinucleotides localized in miRNA encoding genes. Putative target genes of the highest-ranked miRNAs were obtained from the miRDB and included in overrepresentation analyses in the ConsensusPathDB. Expression of target genes was assessed using the RNA sequencing data of retinal ARPE-19 cell line. Results: We identified differential methylation of CG dinucleotides in promoter regions of MIR3621, MIR34C, MIR423 (increased methylation level), and MIR1178, MIRLET7A2, MIR885, MIR548I3, MIR6854, MIR675, MIRLET7C, MIR99A (decreased methylation level) genes. Several targets of these miRNAs, e.g. GNAS, TRAM1, CTNNB1, EIF4B, TENM3 and RUNX were previously associated with myopia/HM/refractive error in Europeans in genome-wide association studies. Overrepresentation analyses of miRNAs' targets revealed enrichment in pathways/processes related to eye structure/function, such as axon guidance, transcription, focal adhesion, and signaling pathways of TGF-β, insulin, MAPK and EGF-EGFR. Conclusion: Differential methylation of indicated miRNA encoding genes might influence their expression and contribute to HM pathogenesis via disrupted regulation of transcription of miRNAs' target genes. Methylation of genes encoding miRNAs may be a new direction in research on both the mechanisms determining HM and non-invasive indicators in diagnostics.