miR-145 and miR20a-5p Potentially Mediate Pleiotropic Effects of Interferon-Beta Through Mitogen-Activated Protein Kinase Signaling Pathway in Multiple Sclerosis Patients

MicroRNAs are dysregulated in peripheral blood mononuclear cells in multiple sclerosis and correlate with T cell mediators

T cell mediators and microRNAs are involved in the pathogenesis of multiple sclerosis (MS), but their interaction largely remains undetermined. We investigated by RT-qPCR the dysregulation of microRNAs in peripheral blood mononuclear cells of MS patients versus healthy controls, according to radiological disease activity or treatment. Several microRNAs correlated positively/negatively with IL21/FOXP3 mRNA expression, but not with serum neurofilament light chain levels. Cytokine expression is conceivably balanced by several regulators, whereas microRNAs possibly target upstream transcription factors rather than directly cytokine mRNAs. Functional studies are needed to investigate their interaction, notably for the predicted targeting of FOXP3 by miR-34c-5p.

Emerging imaging and liquid biomarkers in multiple sclerosis

The advent of highly effective disease modifying therapy has transformed the landscape of multiple sclerosis (MS) care over the last two decades. However, there remains a critical, unmet need for sensitive and specific biomarkers to aid in diagnosis, prognosis, treatment monitoring, and the development of new interventions, particularly for people with progressive disease. This review evaluates the current data for several emerging imaging and liquid biomarkers in people with MS. MRI findings such as the central vein sign and paramagnetic rim lesions may improve MS diagnostic accuracy and evaluation of therapy efficacy in progressive disease. Serum and cerebrospinal fluid levels of several neuroglial proteins, such as neurofilament light chain and glial fibrillary acidic protein, show potential to be sensitive biomarkers of pathologic processes such as neuro-axonal injury or glial-inflammation. Additional promising biomarkers, including optical coherence tomography, cytokines and chemokines, microRNAs, and extracellular vesicles/exosomes, are also reviewed, among others. Beyond their potential integration into MS clinical care and interventional trials, several of these biomarkers may be informative of MS pathogenesis and help elucidate novel targets for treatment strategies.

Current Advancement of Immunomodulatory Drugs as Potential Pharmacotherapies for Autoimmunity Based Neurological Diseases

Dramatic advancement has been made in recent decades to understand the basis of autoimmunity-mediated neurological diseases. These diseases create a strong influence on the central nervous system (CNS) and the peripheral nervous system (PNS), leading to various clinical manifestations and numerous symptoms. Multiple sclerosis (MS) is the most prevalent autoimmune neurological disease while NMO spectrum disorder (NMOSD) is less common. Furthermore, evidence supports the presence of autoimmune mechanisms contributing to the pathogenesis of amyotrophic lateral sclerosis (ALS), which is a neurodegenerative disorder characterized by the progressive death of motor neurons. Additionally, autoimmunity is believed to be involved in the basis of Alzheimer’s and Parkinson’s diseases. In recent years, the prevalence of autoimmune-based neurological disorders has been elevated and current findings strongly suggest the role of pharmacotherapies in controlling the progression of autoimmune diseases. Therefore, this review focused on the current advancement of immunomodulatory drugs as novel approaches in the management of autoimmune neurological diseases and their future outlook.

microRNA Expression and Its Association With Disability and Brain Atrophy in Multiple Sclerosis Patients Treated With Glatiramer Acetate

Background

MicroRNAs are small non-coding RNA that regulate gene expression at a post-transcriptional level affecting several cellular processes including inflammation, neurodegeneration and remyelination. Different patterns of miRNAs expression have been demonstrated in multiple sclerosis compared to controls, as well as in different courses of the disease. For these reason they have been postulated as promising biomarkers candidates in multiple sclerosis.

Objective

to correlate serum microRNAs profile expression with disability, cognitive functioning and brain volume in patients with remitting-relapsing multiple sclerosis.

Methods

cross-sectional study in relapsing-remitting multiple sclerosis patients treated with glatiramer acetate. Disability was measured with Expanded Disability Status Scale (EDSS) and cognitive function was studied with Symbol Digit Modalities Test (SDMT). Brain volume was analyzed with automatic software NeuroQuant®.

Results

We found an association between miR.146a.5p (rs:0.434, p=0.03) and miR.9.5p (rs:0.516, p=0.028) with EDSS; and miR-146a.5p (rs:-0.476, p=0.016) and miR-126.3p (rs:-0.528, p=0.007) with SDMT. Regarding to the brain volume, miR.9.5p correlated with thalamus (rs:-0.545, p=0.036); miR.200c.3p with pallidum (rs:-0.68, p=0.002) and cerebellum (rs:-0.472, p=0.048); miR-138.5p with amygdala (rs:0.73, p=0.016) and pallidum (rs:0.64, p=0.048); and miR-223.3p with caudate (rs:0.46, p=0.04).

Conclusions

These data support the hypothesis of microRNA as potential biomarkers in this disease. More studies are needed to validate these results and to better understand the role of microRNAs in the pathogenesis, monitoring and therapeutic response of multiple sclerosis.

The role of microRNAs in diseases and related signaling pathways

MicroRNAs (miRNAs) are epigenetic regulators of the gene expression and act through posttranslational modification. They bind to 3'-UTR of target mRNAs to inhibit translation or increase the degradation mRNA in many tissues. Any alteration in the level of miRNA expression in many human diseases indicates their involvement in the pathogenesis of many diseases. On the other hand, the regulation of the signaling pathways is necessary for the maintenance of natural and physiological characteristics of any cell. It is worth mentioning that dysfunction of the signaling pathways manifests itself as a disorder or disease. The significant evidence report that miRNAs regulate the several signaling pathways in many diseases. Base on previous studies, miRNAs can be used for therapeutic or diagnostic purposes. According to the important role of miRNAs on the cell signaling pathways, this article reviews miRNAs involvement in incidence of diseases by changing signaling pathways.

Expression and clinical significance of IL7R, NFATc2, and RNF213 in familial and sporadic multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory and autoimmune disorder of the central nervous system characterized by myelin loss and axonal dysfunction. Increased production of inflammatory factors such as cytokines has been implicated in axon destruction. In the present study, we compared the expression level of IL7R, NFATc2, and RNF213 genes in the peripheral blood of 72 MS patients (37 familial MS, 35 sporadic MS) and 74 healthy controls (34 individuals with a family history of the disease, 40 healthy controls without a family history) via Real-time PCR. Our results showed that the expression level of IL7R was decreased in the sporadic patients in comparison with other groups. Additionally, there was an increased NFATc2 expression level in MS patients versus healthy controls. Increased expression of NFATc2 in sporadic and familial groups compared to the controls, and familial group versus FDR was also seen. Our results also represented an increased expression level of RNF213 in familial patients as compared to the control group. The similar RNF213 expression between sporadic and control group, as well as FDR and familial group was also seen. Diagnostic evaluation was performed by receiver operating characteristic (ROC) curve analysis and area under the curve (AUC) calculation. The correlation of clinical parameters including onset age and Expanded Disability Status Scale (EDSS) with our gene expression levels were also assessed. Overall, decreased expression level of IL7R in the sporadic cases and increased expression level of NFATc2 may be associated with the pathogenesis of MS disease. Confirmation of the effects of differential expression of RNF213 gene requires further studies in the wider statistical populations.

miR-20a suppresses Treg differentiation by targeting Map3k9 in experimental autoimmune encephalomyelitis

Background

Experimental autoimmune encephalomyelitis (EAE) is a model for inflammatory demyelinating diseases of the central nervous system (CNS), a group of autoimmune diseases characterized by inflammatory infiltration, demyelination, and axonal damage. miR-20a is dysregulated in patients with CNS inflammatory demyelinating diseases; however, the function of miR-20a remains unclear. In this study, we intended to explore the role of miR-20a in EAE.

Methods

The expression of miR-20a was detected by quantitative real-time PCR (qRT-PCR) in EAE mice and patients with MOG antibody-associated demyelinating diseases. CD4⁺ T cells of EAE mice were sorted, stimulated, and polarized with miR-20a knockdown. Activation and differentiation of CD4⁺ T cells were analyzed by flow cytometry. The expression of target gene Map3k9 was detected by qRT-PCR and western blot experiments. The binding of miR-20a to the 3’ UTR of Map3k9 was tested by luciferase assays. The feasibility of miR-20a as a therapeutic target to alleviate the severity of EAE was explored by intravenous administration of miR-20a antagomirs to EAE mice.

Results

miR-20a was upregulated in splenocytes and lymph node cells, CD4⁺ T cells, and spinal cords of EAE mice. Moreover, miR-20a knockdown did not influence the activation of antigen-specific CD4⁺ T cells but promoted their differentiation into Treg cells. Map3k9 was predicted to be a target gene of miR-20a. The expressions of Map3k9 and miR-20a were negatively correlated, and miR-20a knockdown increased the expression of Map3k9. In addition, miR-20a binded to the 3’ UTR of Map3k9, and simultaneous knockdown of miR-20a and Map3k9 counteracted the enhanced differentiation of Tregs observed when miR-20a was knocked down alone. Furthermore, injection of miR-20a antagomirs to EAE mice reduced the severity of the disease and increased the proportion of Treg cells in peripheral immune organs.

Conclusions

miR-20a suppresses the differentiation of antigen-specific CD4⁺ T cells into Tregs in EAE by decreasing the expression of Map3k9. miR-20a antagomirs alleviate EAE, suggesting a new therapy for EAE and CNS inflammatory demyelinating diseases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-02893-4.

The role of microRNAs in multiple sclerosis

Despite numerous studies on multiple sclerosis (MS) and understanding many aspects of this disease, researchers still struggle to find proper biomarkers that facilitate diagnosis; prognosis and monitoring of treatment efficacy in MS. MicroRNAs (miRNAs) are considered as endogenous, comparatively stable and small non-coding RNAs involved in various biological and pathological signaling pathways. Interestingly, miRNAs have been emerged as a potential biomarker for monitoring novel therapies in MS patients. In this review, we described the miRNAs alteration in the MS patients as well as their altered expression in patients under common MS therapies.

Genetic variations in autoimmune genes and VKH disease

PURPOSE

Vogt-Koyanagi-Harada (VKH) disease is a rare autoimmune disease. The autoimmune response in VKH disease is against the melanin-producing cells; therefore, in affected individuals melanocyte-containing organs manifest disease symptoms including eyes, ears, skin and nervous system. VKH is a multifactorial disease, and the precise cause of the VKH disease is unknown. Studies have suggested that both environmental and genetic factors are responsible for the VKH disease. In this review, the authors have collected all the available literature on the genetics of VKH to their knowledge and discussed the role of genetic variants in causing VKH disease.

METHODS

An extensive literature search was performed in order to review all the published studies regarding VKH clinical phenotyping and genetic variants in VKH disease. Medline, PubMed, Cochrane library, and Scopus was searched using combination of keywords.

RESULTS

It was found that variants in HLA genes, IL-12b, TNFSF4, and miR-20-5p genes are significantly associated with VKH; however, variants in genes ATG10, TNIP1 and CLEC16A did not achieve significant genome-wide association threshold. Moreover, polymorphisms in TNIP1 and CLEC16A play a protective role against VKH.

CONCLUSION

The authors conclude that increased sample size and a more homogeneous VKH patient population may reveal a significant association of variants in ATG10, TNIP1 and CLEC16A genes with VKH disease.

Epigenetics in Multiple Sclerosis

Multiple sclerosis (MS) is an aggravating autoimmune disease that cripples young patients slowly with physical, sensory and cognitive deficits. The break of self-tolerance to neuronal antigens is the key to the pathogenesis of MS, with autoreactive T cells causing demyelination that subsequently leads to inflammation-mediated neurodegenerative events in the central nervous system. The exact etiology of MS remains elusive; however, the interplay of genetic and environmental factors contributes to disease development and progression. Given that genetic variation only accounts for a fraction of risk for MS, extrinsic risk factors including smoking, infection and lack of vitamin D or sunshine, which cause changes in gene expression, contribute to disease development through epigenetic regulation. To date, there is a growing body of scientific evidence to support the important roles of epigenetic processes in MS. In this chapter, the three main layers of epigenetic regulatory mechanisms, namely DNA methylation, histone modification and microRNA-mediated gene regulation, will be discussed, with a particular focus on the role of epigenetics on dysregulated immune responses and neurodegenerative events in MS. Also, the potential for epigenetic modifiers as biomarkers and therapeutics for MS will be reviewed.

microRNAs: key modulators of disease-modifying therapies in multiple sclerosis

There is a high level of heterogeneity in symptom manifestations and response to disease-modifying therapies (DMTs) in multiple sclerosis (MS), an immune-based neurodegenerative disease with ever-increasing prevalence in recent decades. Because of unknown aspects of the etiopathology of MS and mechanism of action of DMTs, the reason for this variability is undetermined, and much remains to be understood. Traditionally, physicians consider switching to other DMTs based on the exacerbation of symptoms and/or change in the results of magnetic resonance imaging and biochemical factors. Therefore, identifying biological treatment response markers that help us recognizing non-responders rapidly and subsequently choosing another DMTs is necessary. microRNAs (miRNAs) are micromanagers of gene expression which have been profiled in different samples of MS patients, highlighting their role in pathogenetic of MS. Recent studies have investigated expression profiling of miRNAs after treatment with DMTs to clarify possible DMTs-mediated mechanism and obtaining response to therapy biomarkers. In this review, we will discuss the modulation of miRNAs by DMTs in cells and pathways involved in MS.

Connection of miR-185 and miR-320a expression levels with response to interferon-beta in multiple sclerosis patients

BACKGROUND

Multiple sclerosis (MS) is an inflammatory autoimmune disease characterized by neurodegeneration in the CNS. Interferon-beta (IFN-β) is an FDA-approved drug used as the first-line treatment for relapse-remitting multiple sclerosis (RRMS). The exact mechanism of IFN-β during the treatment of RRMS still remains unknown. Recently, many studies have shifted towards the role of miRNAs in the treatment of MS patients.

METHODS

Herein, the expression level of miR-185-5p and miR-320a has been evaluated in order to candidate them as novel biomarkers for monitoring the response to IFN-β therapy. For this purpose, one-hundred whole blood samples from patients with RRMS were collected, consisting of 50 responders and 50 non-responders to IFN-β therapy. To predict the possible molecular mechanisms of IFN-β and highlight the role of these miRNAs, in silico analysis was applied to enrich the signaling pathways which may be involved based on the target genes of miR-185-5p and miR-320a.

RESULTS

It is identified that the differentially expressed miR-185-5p was statistically significant between the two treated groups with IFN-β. Furthermore, MAPK signaling pathway was suggested as the main non-canonical pathway involved in IFN-β therapy.

CONCLUSION

miR-185-5p could be considered as a novel biomarker for monitoring the response to IFN-β therapy.

Principal component analysis of blood microRNA datasets facilitates diagnosis of diverse diseases

Early, ideally pre-symptomatic, recognition of common diseases (e.g., heart disease, cancer, diabetes, Alzheimer’s disease) facilitates early treatment or lifestyle modifications, such as diet and exercise. Sensitive, specific identification of diseases using blood samples would facilitate early recognition. We explored the potential of disease identification in high dimensional blood microRNA (miRNA) datasets using a powerful data reduction method: principal component analysis (PCA). Using Qlucore Omics Explorer (QOE), a dynamic, interactive visualization-guided bioinformatics program with a built-in statistical platform, we analyzed publicly available blood miRNA datasets from the Gene Expression Omnibus (GEO) maintained at the National Center for Biotechnology Information at the National Institutes of Health (NIH). The miRNA expression profiles were generated from real time PCR arrays, microarrays or next generation sequencing of biologic materials (e.g., blood, serum or blood components such as platelets). PCA identified the top three principal components that distinguished cohorts of patients with specific diseases (e.g., heart disease, stroke, hypertension, sepsis, diabetes, specific types of cancer, HIV, hemophilia, subtypes of meningitis, multiple sclerosis, amyotrophic lateral sclerosis, Alzheimer’s disease, mild cognitive impairment, aging, and autism), from healthy subjects. Literature searches verified the functional relevance of the discriminating miRNAs. Our goal is to assemble PCA and heatmap analyses of existing and future blood miRNA datasets into a clinical reference database to facilitate the diagnosis of diseases using routine blood draws.

miR-504 expression level is increased in multiple sclerosis patients responder to interferon-beta

Multiple sclerosis is immune-mediated disease of the central nervous system characterized by demyelination in axons. IFN-β is first-line treatment of MS. Biomarkers are needed for early prediction of responders and non-responders to therapy in the first month of treatment to avoid further disabilities. In this study, we analyzed the expression level of miR-504 and miR-711 in 52 IFN-β responder patients in comparison to 53 non-responders. In the next step, the in-silico analysis was used to enrich related signaling pathways. The expression level of miR-504 was significantly higher in patients who respond to IFN-β therapy, compared with non-responders and we obtain related statistically significant KEGG molecular signaling pathways. Our findings suggest that miR-504 can be considered as a novel biomarker for response to IFN-b therapy.

Environmental Influencers, MicroRNA, and Multiple Sclerosis

Multiple sclerosis (MS) is a complex neurological disorder characterized by an aberrant immune system that affects patients' quality of life. Several environmental factors have previously been proposed to associate with MS pathophysiology, including vitamin D deficiency, Epstein-Barr virus (EBV) infection, and cigarette smoking. These factors may influence cellular molecularity, interfering with cellular proliferation, differentiation, and apoptosis. This review argues that small noncoding RNA named microRNA (miRNA) influences these factors' mode of action. Dysregulation in the miRNAs network may deeply impact cellular hemostasis, thereby possibly resulting in MS pathogenicity. This article represents a literature review and an author's theory of how environmental factors may induce dysregulations in the miRNAs network, which could ultimately affect MS pathogenicity.

Precision Medicine in Neurodegenerative Diseases: Some Promising Tips Coming from the microRNAs' World

: Novel insights in the development of a precision medicine approach for treating the neurodegenerative diseases (NDDs) are provided by emerging advances in the field of pharmacoepigenomics. In this context, microRNAs (miRNAs) have been extensively studied because of their implication in several disorders related to the central nervous system, as well as for their potential role as biomarkers of diagnosis, prognosis, and response to treatment. Recent studies in the field of neurodegeneration reported evidence that drug response and efficacy can be modulated by miRNA-mediated mechanisms. In fact, miRNAs seem to regulate the expression of pharmacology target genes, while approved (conventional and non-conventional) therapies can restore altered miRNAs observed in NDDs. The knowledge of miRNA pharmacoepigenomics may offers new clues to develop more effective treatments by providing novel insights into interindividual variability in drug disposition and response. Recently, the therapeutic potential of miRNAs is gaining increasing attention, and miRNA-based drugs (for cancer) have been under observation in clinical trials. However, the effective use of miRNAs as therapeutic target still needs to be investigated. Here, we report a brief review of representative studies in which miRNAs related to therapeutic effects have been investigated in NDDs, providing exciting potential prospects of miRNAs in pharmacoepigenomics and translational medicine.

Elevated microRNA-145 inhibits the development of oral squamous cell carcinoma through inactivating ERK/MAPK signaling pathway by down-regulating HOXA1

Background: Oral cancer is one of the most frequent solid cancers worldwide, and oral squamous cell carcinoma (OSCC) constitutes approximately 90% of oral cancers. The discovery of reliable prognostic indicators would be a potential strategy for OSCC treatment. In the present study, we aim to explore the underlying mechanism by which microRNA-145 (miR-145) affected OSCC. Methods: Forty-eight patients diagnosed with OSCC were enrolled to obtain the OSCC tissues and adjacent normal tissues. The targeting relationship between miR-145 and Homeobox A1 (HOXA1) was verified. In order to assess the effects of miR-145 in OSCC and the detailed regulatory mechanism, the SCC-9 cell line was adopted, in which expression of miR-145 and HOXA1 were altered by transfection. Then, a series of in vitro and in vivo experiments were performed to evaluate the cell viability, migration, invasion, and tumor growth. Results: miR-145 was poorly expressed and HOXA1 was highly expressed in OSCC. HOXA1 was verified as a target of miR-145 to mediate the activation of the extracellular signal-regulated kinase/mitogen activated protein kinase (ERK/MAPK) signaling pathway. In the circumstance of miR-145 elevation or HOXA1 depletion, the SCC-9 cell line manifested with inhibited cell viability, invasion, and migration in vitro, coupled with reduced tumor growth in vivo, with a decreased expression of ERK/MAPK signaling pathway-related genes/proteins. Conclusion: These findings suggested that miR-145 can inhibit HOXA1 to inactivate the ERK/MAPK signaling pathway, thereby suppressing OSCC cell proliferation, migration, and invasion to further inhibit the development of OSCC, highlighting a novel therapeutic target for the OSCC treatment.

MicroRNAs change the games in central nervous system pharmacology

MicroRNAs (miRNAs) represent a class of important post-transcriptional regulators of gene expression, enabling cells to follow their intrinsic developmental program. By directly binding to their targets, miRNAs can both promote transcriptional patterns in crucial steps of cell growth, and act as powerful buffering system that titrate protein content in case of aberrant gene expression. The literature of the last decade showed that the presence of tissue-enriched miRNAs in body fluids could be reminiscent of disease state. This is particularly relevant in neurodegenerative disorders, in which peripheral biomarkers could be helpful means to detect disease onset. However, dysregulation of miRNAs is not merely a consequence of disease, but directly contributes to pathological outcomes. On this basis, increasing interest is growing in the development of pharmacological agents targeting specific miRNAs. Actually, this apparently futuristic approach is already part of the current therapies. In fact, several drugs approved for CNS disorders, such as L-Dopa or valproic acid, were also demonstrated to restore some miRNAs. Moreover, ongoing clinical trials demonstrated that miRNA-based drugs are effective against tumors, suggesting that miRNAs also represent a promising class of therapeutic molecules. However, several issues still need to be addressed, particularly in case of CNS diseases, in which stability and delivery are crucial aspects of the therapy. In this commentary, we highlighted potential advantages and limitations of miRNAs as next generation targets in CNS pharmacology, focusing on multiple sclerosis, a chronic demyelinating disease lacking specific therapeutic targets and bona-fide biomarkers.

miR-145 eliminates lipopolysaccharides-induced inflammatory injury in human fibroblast-like synoviocyte MH7A cells

Recently, it has been accepted that miR-based therapy may be beneficial for rheumatoid arthritis (RA). This study aimed to evaluate the potential involvement of miR-145 in RA in vitro. The expression of miR-145 in the human fibroblast-like synoviocyte line MH7A was overexpressed by miR-mimic transfection, after which cells were subjected to lipopolysaccharides (LPS). Cell viability, apoptosis, and the release of pro-inflammatory cytokines were measured. The result showed that the apoptosis and the release of IL-1β, IL-6, IL-8, and TNF-α were significantly induced by LPS. Meanwhile, LPS treatment led to downregulation of miR-145. miR-145 overexpression in LPS-untreated MH7A cells had no impacts on cell apoptosis and inflammation. But, restoring miR-145 expression in LPS-stimulated cells by supplementation of a miR-145 mimic protected MH7A cells against LPS-induced apoptosis and inflammation. Furthermore, miR-145 overexpression in LPS-untreated MH7A cells slightly blocked the PI3K/ATK and mTOR pathways, whereas miR-145 overexpression in LPS-stimulated cells notably repressed the LPS-induced activation of PI3K/ATK and MAPK/mTOR pathways. Our study suggested that miR-145 protected MH7A cells against LPS-induced apoptosis and inflammation by inhibiting the PI3K/AKT and MAPK/mTOR pathways.

MicroRNA-20a-5p suppresses IL-17 production by targeting OSM and CCL1 in patients with Vogt-Koyanagi-Harada disease

Aim

To elucidate the role of microRNA-20a-5p (miR-20a-5p) in the pathogenesis of Vogt-Koyanagi-Harada (VKH) disease.

Methods

Quantitative real-time PCR was used to quantify miR-20a-5p expression in CD4+ T cells from patients with active VKH and normal controls. The promoter methylation status of miR-20a-5p was detected by bisulfite sequencing PCR. Targets were evaluated by a luciferase reporter assay. The functional effects of miR-20a-5p on CD4+ T cells from patients with active VKH were assessed by upregulation or downregulation of its expression using liposomes.

Results

The miR-20a-5p level was significantly decreased in CD4+ T cells from patients with active VKH as compared with normal controls. The two genes, oncostatin M (OSM) and C-C motif chemokine ligand 1 (CCL1), were identified as targets of miR-20a-5p. The upregulation of miR-20a-5p significantly suppressed interleukin 17 (IL-17) production in CD4+ T cells from patients with active VKH, whereas downregulation of miR-20a-5p exhibited an inverse effect. In addition, overexpression of OSM and CCL1 could rescue the effect of the upregulation of miR-20a-5p. Moreover, the level of miR-20a-5p was reduced in response to hypermethylation of the promoter. Further study showed that miR-20a-5p suppressed the activity of the phosphoinositide 3-kinase-AKT pathway.

Conclusions

Our findings indicate that downregulation of miR-20a-5p is caused by promoter hypermethylation. MiR-20a-5p could also suppress the production of IL-17 by targeting OSM and CCL1 production in CD4+ T cells in patients with active VKH.