MicroRNAs in systemic rheumatic diseases

MiR-146a (rs2910164) Gene Polymorphism and Its Impact on Circulating MiR-146a Levels in Patients with Inflammatory Bowel Diseases

MicroRNA-146a (miR-146a) has been involved in the pathophysiology of inflammatory bowel disease (IBD). However, the precise processes are still not entirely understood. Contradictory studies suggest that miR-146a expression could be influenced by the miR-146a rs2910164 C > G polymorphism. This case-control study aimed to investigate the association of miR-146a rs2910164 C > G gene polymorphism and its impact on circulating miR-146a expression levels in Egyptian IBD patients. We included 40 IBD patients and 30 matched healthy controls. Genotyping of miR-146a rs2910164 polymorphism and assessment of miR-146a expression level were done using quantitative real-time PCR in all participants. MiR-146a rs2910164 GG genotype and the G allele were reported in 47% and 70% of the IBD patient group, respectively. And they were associated with increased IBD risk. All the IBD patients with the CC genotype (100%) and most of those with the CG genotype (66.67%) had an inactive disease, while most IBD patients with the GG genotype (73.68%) had an active disease. The miR-146a expression level was the highest with the CC genotype and the lowest with the GG genotype. Also, miR-146a expression level decreased significantly in IBD patients than controls and with disease activity. Combined detection of fecal calprotectin with miR-146a expression level improved the diagnostic sensitivity and the negative predictive value in differentiating IBD patients with active disease from those inactive. Our study identified a strong association of miR-146a rs2910164 GG genotype and G allele with IBD-increased susceptibility and activity in the Egyptian population. The miR-146a rs2910164 polymorphism can reduce miR-146a expression levels in these patients as well. Further research on a larger sample size and different ethnic populations can be the key to progress in establishing this genetic association.

New insights at the interface between leprosy and immune-mediated rheumatic diseases

Leprosy is an infectious and contagious disease of slow evolution, triggered by Mycobacterium leprae. Arthritis is its third most common manifestation, after cutaneous and peripheral nerve involvement. Since musculoskeletal symptoms may be the initial presentation of the disease, it is important for health professionals to recognize its rheumatic manifestations for early diagnosis and appropriate treatment, especially in endemic areas. In addition, cases of leprosy have increased globally, notably in patients undergoing treatment with TNF-α blockers and due to the increase in migration and travel of people from developing countries to developed countries. This review proposes to discuss the main scenarios of mimicry of different rheumatic diseases by leprosy, as well as the role of immunosuppressive drugs used in rheumatology practice in the treatment of reactional states and in the risk of developing the infection.

Neighborhood-based inference and restricted Boltzmann machine for small molecule-miRNA associations prediction

Background

A growing number of experiments have shown that microRNAs (miRNAs) can be used as target of small molecules (SMs) to regulate gene expression for treating diseases. Therefore, identifying SM-related miRNAs is helpful for the treatment of diseases in the domain of medical investigation.

Methods

This article presents a new computational model, called NIRBMSMMA (neighborhood-based inference (NI) and restricted Boltzmann machine (RBM)), which we developed to identify potential small molecule-miRNA associations (NIRBMSMMA). First, grounded on known SM-miRNAs associations, SM similarity and miRNA similarity, NI was used to predict score of an unknown SM-miRNA pair by reckoning the sum of known associations between neighbors of the SM (miRNA) and the miRNA (SM). Second, utilizing a two-layered generative stochastic artificial neural network, RBM was used to predict SM-miRNA association by learning potential probability distribution from known SM-miRNA associations. At last, an ensemble learning model was conducted to combine NI and RBM for identifying potential SM-miRNA associations.

Results

Furthermore, we conducted global leave one out cross validation (LOOCV), miRNA-fixed LOOCV, SM-fixed LOOCV and five-fold cross validation to assess performance of NIRBMSMMA based on three datasets. Results showed that NIRBMSMMA obtained areas under the curve (AUC) of 0.9912, 0.9875, 0.8376 and 0.9898 ± 0.0009 under global LOOCV, miRNA-fixed LOOCV, SM-fixed LOOCV and five-fold cross validation based on dataset 1, respectively. For dataset 2, the AUCs are 0.8645, 0.8720, 0.7066 and 0.8547 ± 0.0046 in turn. For dataset 3, the AUCs are 0.9884, 0.9802, 0.8239 and 0.9870 ± 0.0015 in turn. Also, we conducted case studies to further assess the predictive performance of NIRBMSMMA. These results illustrated the proposed model is a useful tool in predicting potential SM-miRNA associations.

Systemic lupus erythematosus: From non-coding RNAs to exosomal non-coding RNAs

Systemic lupus erythematosus (SLE), as an immunological illness, frequently impacts young females. Both vulnerabilities to SLE and the course of the illness's clinical symptoms have been demonstrated to be affected by individual differences in non-coding RNA expression. Many non-coding RNAs (ncRNAs) are out of whack in patients with SLE. Because of the dysregulation of several ncRNAs in peripheral blood of patients suffering from SLE, these ncRNAs to be showed valuable as biomarkers for medication response, diagnosis, and activity. NcRNAs have also been demonstrated to influence immune cell activity and apoptosis. Altogether, these facts highlight the need of investigating the roles of both families of ncRNAs in the progress of SLE. Being aware of the significance of these transcripts perhaps elucidates the molecular pathogenesis of SLE and could open up promising avenues to create tailored treatments during this condition. In this review we summarized various non-coding RNAs and Exosomal non-coding RNAs in SLE.

miRNAs insights into rheumatoid arthritis: Favorable and detrimental aspects of key performers

Rheumatoid arthritis (RA) is a severe autoimmune inflammation that mostly affects the joints. It's a multifactorial disease. Its clinical picture depends on genetic and epigenetic factors such as miRNAs. The miRNAs are small noncoding molecules that are able to negatively or positively modulate their target gene expression. In RA, miRNAs are linked to its pathogenesis. They disrupt immunity balance by controlling granulocytes, triggering the release of several proinflammatory cytokines such as interleukin-6 and tumor necrosis factor-α, finally leading to synovium hyperplasia and inflammation. Besides, they also may trigger activation of some pathways as nuclear factor kappa-β disrupts the balance between osteoclast and osteoblast activity, leading to increased bone destruction. Moreover, miRNAs are also applied with efficiency in RA diagnosis and prognosis. Besides the significant association between miRNAs and RA response to treatment, they are also applied as a choice for treatment based on their effects on the immune system and inflammatory cytokines. Hence, the review aims to present an updated overview of miRNAs, their biogenesis, implications in RA pathogenesis, and finally, the role of miRNAs in RA treatment.

lncRNA-mediated synovitis in rheumatoid arthritis: A perspective for biomarker development

Long noncoding RNAs (lncRNAs) are a regulatory class of noncoding RNAs with a wide range of activities such as transcriptional and post-transcriptional regulations. Emerging evidence has demonstrated that various lncRNAs contribute to the initiation and progression of Rheumatoid Arthritis (RA) through distinctive mechanisms. The present study reviews the recent findings on lncRNA role in RA development. It focuses on the involvement of different lncRNAs in the main steps of RA pathogenesis including T cell activation, cytokine dysregulation, fibroblast-like synoviocyte (FLS) activation and joint destruction. Besides, it discusses the current findings on RA diagnosis and the potential of lncRNAs as diagnostic, prognostic and predictive biomarkers in Rheumatology clinic.

Expression of the miR-9-5p, miR-125b-5p and its target gene NFKB1 and TRAF6 in childhood-onset systemic lupus erythematosus (cSLE)

Childhood- onset systemic lupus erythematosus (cSLE) is a multisystem inflammatory disease that can lead to severe clinical conditions resulting in early comorbidities. Several genetic, environmental, and immunological factors are known to influence the onset of the disease. MiRNAs have been already considered as potential actors involved in the development and activity of the SLE. Thus, understanding the behavior of these regulators can contribute to clarify the inflammatory process affecting SLE patients. Among miRNAs, miR-125b-5p and miR-9-5p targeting NFKB1 and TRAF6 genes can be involved in the etio-pathogenesis of the disease by modulating inflammation. In this study we evaluated miR-9-5p and miR-125b-5p expression and its target genes NFKB1 and TRAF6 in peripheral blood samples (PBMC) from the 35 cSLE patients and 35 healthy controls. MiRNAs and gene target expression have been evaluated by using RT-PCR with specific TaqMan® probes. Both miR-9-5p [Fold Change (FC) = -2.21; p = 0.002] and miR-125b-5p (FC= -3.30; p < 0.0001) and NFKB1 (FC = -1.84; p < 0.001) were downregulated in cSLE patients, while TRAF6 was upregulated (FC = 1.80; p = 0.006) in cSLE patients when compared to controls. A significant correlation was found between miR-125b-5p and its target gene NFKB1 [Spearman (r) = 0.47; p = 0.023]. Our results showed miR-125b-5p and miR-9-5p differential expression in cSLE patients, possibly contributing to better understanding the role of these regulators in cSLE development and disease pathogenesis.

Regulation of mi-RNAs Target Cancer Genes Between Exercise and Non-exercise in Rat Rheumatoid Arthritis Induction: Pilot Study

Introduction:

Rheumatoid arthritis is associated with various cancers. Many studies have investigated physical exercise interventions as health improvements to ameliorate the risk of cancer during rheumatoid arthritis diagnosis. Recently, microRNAs were used as biomarkers for health assessment and cancer prediction in rheumatoid arthritis patients.

Methods:

The effects of exercise interventions on serum microRNAs were investigated in pristane-induced arthritis (PIA) rat models. Twelve Sprague-Dawley male rats were divided into 4 groups including non-exercise without PIA (N-EX), non-exercise with PIA (N-EX + PIA), exercise without PIA (EX) and exercise with PIA (EX + PIA). Blood samples were collected at the end of the study period to analyze miRNA biomarkers and target cancer gene predictions.

Results:

Four significant Rattus norvegicus (rno-microRNAs) may purpose as tumor suppressors were identified as potential target cancer gene candidate expressions within the 4 comparative interventional exercise groups. One rno-microRNA and target cancer gene candidate was up-regulated and 3 rno-microRNAs and their target cancer genes were down-regulated.

Conclusions:

Exercise interventions affected rno-miRNAs regulated target cancer gene candidates ITPR3, SOCS6, ITGA6, and NKX2-1 as biomarkers for cancer prognosis in rheumatoid arthritis diagnosis.

MicroRNAs (miRNAs) in Cardiovascular Complications of Rheumatoid Arthritis (RA): What Is New?

Rheumatoid Arthritis (RA) is among the most prevalent and impactful rheumatologic chronic autoimmune diseases (AIDs) worldwide. Within a framework that recognizes both immunological activation and inflammatory pathways, the exact cause of RA remains unclear. It seems however, that RA is initiated by a combination between genetic susceptibility, and environmental triggers, which result in an auto-perpetuating process. The subsequently, systemic inflammation associated with RA is linked with a variety of extra-articular comorbidities, including cardiovascular disease (CVD), resulting in increased mortality and morbidity. Hitherto, vast evidence demonstrated the key role of non-coding RNAs such as microRNAs (miRNAs) in RA, and in RA-CVD related complications. In this descriptive review, we aim to highlight the specific role of miRNAs in autoimmune processes, explicitly on their regulatory roles in the pathogenesis of RA, and its CV consequences, their main role as novel biomarkers, and their possible role as therapeutic targets.

Identification and Contribution of Inflammation-Induced Novel MicroRNA in the Pathogenesis of Systemic Lupus Erythematosus

Recently microRNAs (miRNAs) have been recognized as powerful regulators of many genes and pathways involved in the pathogenesis of inflammatory diseases including Systemic Lupus Erythematosus (SLE). SLE is an autoimmune disease characterized by production of various autoantibodies, inflammatory immune cells, and dysregulation of epigenetic changes. Several candidate miRNAs regulating inflammation and autoimmunity in SLE are described. In this study, we found significant increases in the expression of miR21, miR25, and miR186 in peripheral blood mononuclear cells (PBMCs) of SLE patients compared to healthy controls. However, miR146a was significantly decreased in SLE patients compared to healthy controls and was negatively correlated with plasma estradiol levels and with SLE disease activity scores (SLEDAI). We also found that protein levels of IL-12 and IL-21 were significantly increased in SLE patients as compared to healthy controls. Further, our data shows that protein levels of IL-12 were positively correlated with miR21 expression and protein levels of IL-21 positively correlated with miR25 and miR186 expression in SLE patients. In addition, we found that levels of miR21, miR25, and miR186 positively correlated with SLEDAI and miR146a was negatively correlated in SLE patients. Thus, our data shows a dynamic interplay between disease pathogenesis and miRNA expression. This study has translational potential and may identify novel therapeutic targets in patients with SLE.

Association between Maternal Periodontitis and Development of Systematic Diseases in Offspring

Periodontal disease (PD) is one of the most common oral conditions affecting both youths and adults. There are some research works suggesting a high incidence of PD in pregnant women. As an inflammatory disease of bacterial origin, PD may result in the activation of the pathways affecting the course and the pregnancy outcome. The authors, based on the literature review, try to answer the PICO question: Does maternal periodontitis (exposure) influence the incidence of complications rates in pregnancy and the development of systemic diseases in childhood and adult offspring (outcome) in the humans of any race (population) compared to the offspring of mothers with healthy periodontium (comparison)? The authors try to describe the molecular pathways and mechanisms of these interdependencies. There is some evidence that maternal periodontitis may affect the pregnancy course and outcome, resulting in preeclampsia, preterm delivery, vulvovaginitis and low birth weight. It can be suggested that maternal periodontitis may affect offspring epigenome and result in some health consequences in their adult life.

Downregulation of Renal Hsa-miR-127-3p Contributes to the Overactivation of Type I Interferon Signaling Pathway in the Kidney of Lupus Nephritis

MicroRNAs are involved in the pathogenesis of systemic lupus erythematosus (SLE) and dysregulated in the kidneys of lupus nephritis (LN) patients, but their pathogenic roles in LN are largely unknown. Janus Kinase 1 (JAK1) mediates the activation of the downstream signaling pathways of many inflammatory cytokines, including type I interferon (IFN-I) signaling pathway which is critical to the development of SLE and LN. Thus, JAK1 is a potent therapeutic target for these autoimmune diseases. However, there are few studies demonstrating the dysregulation of JAK1 in autoimmune diseases and the molecular mechanism behind it. In this concise report, we show an inhibitory effect of hsa-miR-127-3p, a microRNA that is downregulated in the renal tissues of LN patients, on IFN-I signaling. We found the overexpression of hsa-miR-127-3p could inhibit the induction of ISRE and GAS mediated gene expression, the phosphorylation of STAT1 and STAT2, and the upregulation of IFN stimulated genes (ISGs) stimulated by IFN-I. While, hsa-miR-127-3p antagonist enhanced the activation of IFN-I signaling in primary renal mesangial cells. Subsequently, we identified JAK1 as a bona fide target gene of hsa-miR-127-3p and showed hsa-miR-127-3p targeted JAK1 through binding to its 3’UTR and coding region. Consistently, we found the downregulation of hsa-miR-127-3p was associated with the upregulation of JAK1 and ISGs in kidney tissues of LN patients. Our data indicate renal downregulation of hsa-miR-127-3p contributes to the overactivation of IFN-I signaling pathway in the kidneys of LN patients through promoting the expression of JAK1, suggesting hsa-miR-127-3p mimics may be used to inhibit JAK1 and IFN-I signaling pathway in LN.

Highlighting the interplay of microRNAs from Leishmania parasites and infected-host cells

Leishmania parasites, the causative agents of leishmaniasis, are protozoan parasites with the ability to modify the signalling pathway and cell responses of their infected host cells. These parasite strategies alter the host cell environment and conditions favouring their replication, survival and pathogenesis. Since microRNAs (miRNAs) are able to post-transcriptionally regulate gene expression processes, these biomolecules can exert critical roles in controlling Leishmania-host cell interplay. Therefore, the identification of relevant miRNAs differentially expressed in Leishmania parasites as well as in infected cells, which affect the host fitness, could be critical to understand the infection biology, pathogenicity and immune response against these parasites. Accordingly, the current review aims to address the differentially expressed miRNAs in both, the parasite and infected host cells and how these biomolecules change cell signalling and host immune responses during infection. A deep understanding of these processes could provide novel guidelines and therapeutic strategies for managing and treating leishmaniasis.

Serum Exosomal miRNA-1915-3p Is Correlated With Disease Activity of Korean Rheumatoid Arthritis

BACKGROUND/AIM

It has been found that microRNAs (miRNA) affect rheumatoid arthritis (RA) pathophysiology. This study aimed to identify novel serum exosomal miRNAs related to RA disease activity in patients with an inadequate treatment response.

PATIENTS AND METHODS

The sample population comprised clinical remission (CR) and non-clinical remission (non-CR) groups of RA patients. To identify potent miRNA markers for RA disease activity, miRNA array and qPCR were performed after patient serum exosomes preparation.

RESULTS

Has-miR-1915-3p and has-miR-6511b-5p were significantly higher in the serum exosomes of the CR group. The level of serum C-reactive protein (CRP) was negatively correlated with has-miR-1915-3p level in serum exosomes.

CONCLUSION

Has-miR-1915-3p may be a potential marker for Korean RA disease activity.

GWAS for autoimmune Addison's disease identifies multiple risk loci and highlights AIRE in disease susceptibility

Autoimmune Addison's disease (AAD) is characterized by the autoimmune destruction of the adrenal cortex. Low prevalence and complex inheritance have long hindered successful genetic studies. We here report the first genome-wide association study on AAD, which identifies nine independent risk loci (P < 5 × 10^-8). In addition to loci implicated in lymphocyte function and development shared with other autoimmune diseases such as HLA, BACH2, PTPN22 and CTLA4, we associate two protein-coding alterations in Autoimmune Regulator (AIRE) with AAD. The strongest, p.R471C (rs74203920, OR = 3.4 (2.7-4.3), P = 9.0 × 10^-25) introduces an additional cysteine residue in the zinc-finger motif of the second PHD domain of the AIRE protein. This unbiased elucidation of the genetic contribution to development of AAD points to the importance of central immunological tolerance, and explains 35-41% of heritability (h²).

Osteoimmunological insights into the pathogenesis of ankylosing spondylitis

Ankylosing spondylitis (AS) is inflammatory arthritis predominantly affecting the spine, which is involved in the disorders of both immune and skeletal systems. The exact pathogenesis of AS is not fully understood. Osteoimmunology is a new subject of study in inflammatory arthritis, in particular the pathogenic events involved in the cross-regulation of both skeletal and immune systems. In this review, we discuss osteoimmunological and pathological changes of AS in the spine that are characterized by altered osteogenesis and osteolytic bone destruction, accompanied by the changes of the immune system. It was revealed that bone cells like mesenchymal stem cells, osteoblast, and osteoclast in crossing talking with immune cells such as T cells, B cells coregulate to the pathogenesis of AS. Further, an array of cytokines and molecules expressed by both skeletal and immune systems contribute to these complex interplays. Understanding the cellular and molecular mechanisms underlying the pathogenesis of AS will lay a foundation for the exploration of the potential new treatment to AS.

Effect of cardiac rehabilitation on circulating microRNA expression in heart failure: a preliminary study

OBJECTIVES

There are benefits of exercise-based cardiac rehabilitation (CR) in patients with heart failure (HF), but their underlying molecular mechanisms remain elusive. The effect of CR on the expression profile of circulating microRNAs (miRNAs), which are short noncoding RNAs that regulate posttranscriptional expression of target genes, is unknown. If miRNAs respond to changes following CR for HF, then serum profiling of miRNAs may reveal cardioprotective mechanisms of CR.

METHODS

This study enrolled three hospitalized patients with progressed systolic HF and three normal volunteer controls. In patients, CR was initiated after improvement of HF, which included 2 weeks of bicycle ergometer and resistance exercises. Genome-wide expression profiling of circulating miRNAs was performed using microarrays for the patients (mean±SD age, 60.0±12.2 years) and controls (58.7±0.58 years). Circulating miRNA expression profiles were compared between patients with HF before and after CR and the controls.

RESULTS

Expression levels of two miRNAs were significantly different in patients before CR compared with controls and patients after CR. The expression of hsa-miR-125b-1-3p was significantly downregulated and that of hsa-miR-1290 was significantly upregulated in patients before CR.

CONCLUSIONS

When performing CR, expression of certain circulating miRNAs in patients with HF is restored to nonpathological levels. The benefits of CR for HF may result from regulation of miRNAs through multiple effects of gene expression.

Dysregulation of genes and microRNAs in localized aggressive periodontitis

AIM

Previous data from our laboratory have demonstrated that localized aggressive periodontitis (LAP) patients produce elevated levels of pro-inflammatory cytokines in response to TLR4 and TLR2 ligation compared to unrelated and periodontally healthy controls (HC). The aim of the present work is to evaluate the contribution of TLR-related gene expression and miRNA regulation in LAP disease.

MATERIAL AND METHODS

Peripheral blood mononuclear cells (PBMCs) from LAP and health control (HC) patients were isolated. Gene and miRNA expression involved in TLR signalling pathway and immunopathology were evaluated in unstimulated PBMCs by real-time PCR (RT-PCR).

RESULTS

TICAM-1 (TRIF), FOS, IRAK1, TLR2 and CCL2 genes and the miRNAs miR-9-5p, miR-155-5p and 203a-3p, miR-147a, miR-182-5p and miR-183-5p were significantly up-regulated in LAP compared to HC.

CONCLUSIONS

Most of the genes and miRNAs overexpressed here are directly or indirectly related to immune response and inflammation. This profile supports our previous findings that suggests LAP patients have a "hyper-responsive" phenotype upon activation of TLR pathway by periodontal pathogens.

Epigenetics and systemic sclerosis: An answer to disease onset and evolution?

There is growing evidence that implicates epigenetic modification in the pathogenesis of systemic sclerosis (SSc). The complexity of epigenetic regulation and its dynamic nature complicate the investigation of its role in the disease. We will review the current literature for factors that link epigenetics to SSc by discussing DNA methylation, histone acetylation and methylation, and non-coding RNAs (ncRNAs), particularly microRNA changes in endothelial cells, fibroblasts (FBs), and lymphocytes. These three cell types are significantly involved in the early stages and throughout the course of the disease and are particularly vulnerable to epigenetic regulation. The pathogenesis of SSc is likely related to modifications of the epigenome by environmental signals in individuals with a specific genetic makeup. The epigenome is an attractive therapeutic target; however, successful epigenetics-based treatments require a better understanding of the molecular mechanisms controlling the epigenome and its alteration in the disease.

Upregulation of MicroRNA-125b Leads to the Resistance to Inflammatory Injury in Endothelial Progenitor Cells

Objectives

MicroRNA-125b (miR-125b) has been recognized as one of the key regulators of the inflammatory responses in cardiovascular diseases recently. This study sought to dissect the role of miR-125b in modulating the function of endothelial progenitor cells (EPCs) in the inflammatory environment of ischemic hearts.

Methods

EPCs were cultured and transfected with miR-125b mimic and negative control mimic. Cell migration and adhesion assays were performed after tumor necrosis factor-α (TNF-α) treatment to determine EPC function. Cell apoptosis was analyzed by flow cytometry. The activation of the NF-κB pathway was measured by western blotting. EPC-mediated neovascularization in vivo was studied by using a myocardial infarction model.

Results

miR-125b-overexpressed EPCs displayed improved cell migration, adhesion abilities, and reduced cell apoptosis compared with those of the NC group after TNF-α treatment. miR-125b overexpression in EPCs ameliorated TNF-α-induced activation of the NF-κB pathway. Mice transplanted with miR-125b-overexpressed EPCs showed improved cardiac function recovery and capillary vessel density than the ones transplanted with NC EPCs.

Conclusions

miR-125b protects EPCs against TNF-α-induced inflammation and cell apoptosis by attenuating the activation of NF-κB pathway and consequently improves the cardiac function recovery and EPC-mediated neovascularization in the ischemic hearts.

Impaired microRNA processing in neutrophils from rheumatoid arthritis patients confers their pathogenic profile. Modulation by biological therapies

The aim of this study was to investigate the microRNA (miRNA) expression pattern in neutrophils from rheumatoid arthritis (RA) patients and its contribution to their pathogenic profile and to analyze the effect of specific autoantibodies or inflammatory components in the regulation of miRNA in RA neutrophils and its modulation by biological therapies. Neutrophils were isolated from paired peripheral blood (PB) and synovial fluid samples of 40 patients with RA and from PB of 40 healthy donors. A miRNA array was performed using nCounter technology. Neutrophils from healthy donors were treated in vitrowith antibodies to citrullinated protein antigens isolated from RA patients and tumor necrosis factor-a (TNF-a) or interleukin-6. A number of cytokines and chemokines were analyzed. In vitro treatments of RA-neutrophils with tocilizumab or infliximab were carried out. Transfections with pre-miRNA and DICER downregulation experiments were further performed. RA-neutrophils showed a global downregulation of miRNA and genes involved in their biogenesis, alongside with an upregulation of various potential mRNA targets related to migration and inflammation. Decreased levels of miRNA and DICER correlated with autoimmunity, inflammation and disease activity. Citrullinated protein antigens and TNF-a decreased the expression of numerous miRNA and their biogenesis-related genes, increasing their potential mRNA targets. Infliximab reversed those effects. Transfections with pre-miRNA-223, -126 and -148a specifically modulated genes regulating inflammation, survival and migration whereas DICER depletion influenced the inflammatory profile of neutrophils. Taken together RA-neutrophils exhibited a global low abundance of miRNA induced by autoantibodies and inflammatory markers, which potentially contributed to their pathogenic activation. miRNA biogenesis was significantly impaired in RAneutrophils and further associated with a greater downregulation of miRNA mainly related to migration and inflammation in synovial fluid neutrophils. Finally, anti-TNF-a and anti-interleukin-6 receptor treatments can modulate miRNA levels in the neutrophils, minimizing their inflammatory profile.

From the Argonauts Mythological Sailors to the Argonautes RNA-Silencing Navigators: Their Emerging Roles in Human-Cell Pathologies

Regulation of gene expression has emerged as a fundamental element of transcript homeostasis. Key effectors in this process are the Argonautes (AGOs), highly specialized RNA-binding proteins (RBPs) that form complexes, such as the RNA-Induced Silencing Complex (RISC). AGOs dictate post-transcriptional gene-silencing by directly loading small RNAs and repressing their mRNA targets through small RNA-sequence complementarity. The four human highly-conserved family-members (AGO1, AGO2, AGO3, and AGO4) demonstrate multi-faceted and versatile roles in transcriptome’s stability, plasticity, and functionality. The post-translational modifications of AGOs in critical amino acid residues, the nucleotide polymorphisms and mutations, and the deregulation of expression and interactions are tightly associated with aberrant activities, which are observed in a wide spectrum of pathologies. Through constantly accumulating information, the AGOs’ fundamental engagement in multiple human diseases has recently emerged. The present review examines new insights into AGO-driven pathology and AGO-deregulation patterns in a variety of diseases such as in viral infections and propagations, autoimmune diseases, cancers, metabolic deficiencies, neuronal disorders, and human infertility. Altogether, AGO seems to be a crucial contributor to pathogenesis and its targeting may serve as a novel and powerful therapeutic tool for the successful management of diverse human diseases in the clinic.

Serum LINC00305 expression and its genetic variant rs2850711 are associated with clinical and laboratory features of rheumatoid arthritis

BACKGROUND

Long intergenic non-protein coding (lnc) RNA 00305 (LINC00305) is a pro-inflammatory atherosclerosis-associated lncRNA. We hypothesised that LINC00305 expression and its variant rs2850711 (A/T) are implicated in rheumatoid arthritis (RA) and linked with clinical and routine laboratory markers.

METHODS

100 RA patients and 100 healthy controls were recruited. LINC00305 genotyping and expression were performed using allelic-discrimination PCR and quantitative real-time PCR. LINC00305 diagnostic power was evaluated using area under the receiver operating characteristic curve (AUC). Serum nuclear factor- κB (NF-κB) and matrix metalloproteinase-3 (MMP-3) levels were determined by ELISA, standard laboratory markers by routine methods.

RESULTS

LINC00305 expression was significantly increased in RA patients and positively correlated with DAS28, C-reactive protein, erythrocyte sedimentation rate, rheumatoid factor and anti-cyclic citrullinated peptide antibody. In multivariate analysis, NF-κB, MMP-3 and LINC00305 were significant predictors of RA (P< 0.0001). Individuals carrying AT and TT genotypes of rs2850711 polymorphism had significantly more likely to have RA than AA genotype carriers (P< 0.05). LINC00305 expression, DAS28 score and serum levels of NF-κB and MMP-3 were significantly increased in the patients carrying LINC00305 AT and TT genotypes as compared with AA genotype patients (P< 0.01).

CONCLUSION

Increased expression level of LINC00305 and its rs2850711 genetic variant may play a role in the diagnosis and management of RA, and its severity and activity.

The dual role of mir-146a in metastasis and disease progression

OBJECTIVE

MicroRNAs are ribonucleic acids that are single-stranded and endogenous non-coding acids that regulate gene expression in later stages of the translation process by binding to genomic regulatory sites. miR146a is mostly involved in the regulation of inflammatory systems and another process that role in the innate immune system. In the present review, we have focused on the recent acquisitions about the main role played by mir146a in the control of the immune system and tumorigenesis. The main purpose of this review article is to systematically investigate the mir146a and its role in regulating signaling pathways involved in cancer and the immune system as well as its involved therapeutic methods.

METHODS

Systematic search of MEDLINE, Web of Science and Cochrane Library was conducted for all comparative studies from 2000 to 2019 with the limitations of the English language.

RESULTS

For a notable period of time, researchers have mainly focused on the therapeutic mechanisms of mir146a involved in the modulation of inflammatory and anti-inflammatory genes. We found that levels of mir146a expression were associated with cancer cell metastasis as a dual role (Inhibitory and stimulatory roles). The results of various studies also showed that this microRNA has a therapeutic role through its effects on other gene expressions such as NF-kB, SIRT1, TNF- α and IL-1β and leads to disease control.

CONCLUSION

Knowledge about alterations in mir146a regulation will give a better understanding of the molecular basis for various chronic inflammatory diseases and cancers.

Assessment of Circulating Microribonucleic Acids in Patients With Familial Mediterranean Fever

Objectives

This study aims to evaluate the plasma expression of microribonucleic acids (miRNAs) that may be associated with the pathogenesis of familial Mediterranean fever (FMF).

Patients and methods

Thirty patients with FMF (18 males, 12 females; mean age 9.1±4.7 years; range, 3 to 15.5 years) and 30 age- and sex-matched healthy children (18 males, 12 females; mean age 9.5±4.6 years; range, 4 to 16.5 years) were included in this study. The plasma levels of four candidate miRNAs (miRNA-16, miRNA-155, miRNA-204 and miRNA-451) were measured in all subjects. The plasma levels of miRNAs were analyzed with real- time polymerase chain reaction in attack and remission periods of patients and healthy controls (HCs).

Results

Plasma miRNA-204 levels of FMF patients were decreased 6.5 fold in remission period compared to HCs (p<0.001). This decrease was more prominent in M694V mutation carriers. Plasma miRNA-155 levels of FMF patients were lower in remission period (p=0.03).

Conclusion

Our findings showed significant alterations in the plasma expression of miRNA-155 and miRNA-204 in FMF patients compared to HCs. Our data suggest that miRNA-155 and miRNA-204 may be related to the pathogenesis of FMF. Further comprehensive and functional researches may help to clarify the role of miRNAs in FMF and elucidate the pathogenesis of the disease.

Genome-wide association study revealed novel loci which aggravate asymptomatic hyperuricaemia into gout

Objective

The first ever genome-wide association study (GWAS) of clinically defined gout cases and asymptomatic hyperuricaemia (AHUA) controls was performed to identify novel gout loci that aggravate AHUA into gout.

Methods

We carried out a GWAS of 945 clinically defined gout cases and 1003 AHUA controls followed by 2 replication studies. In total, 2860 gout cases and 3149 AHUA controls (all Japanese men) were analysed. We also compared the ORs for each locus in the present GWAS (gout vs AHUA) with those in the previous GWAS (gout vs normouricaemia).

Results

This new approach enabled us to identify two novel gout loci (rs7927466 of CNTN5 and rs9952962 of MIR302F) and one suggestive locus (rs12980365 of ZNF724) at the genome-wide significance level (p<5.0×10^–8). The present study also identified the loci of ABCG2, ALDH2 and SLC2A9. One of them, rs671 of ALDH2, was identified as a gout locus by GWAS for the first time. Comparing ORs for each locus in the present versus the previous GWAS revealed three ‘gout vs AHUA GWAS’-specific loci (CNTN5, MIR302F and ZNF724) to be clearly associated with mechanisms of gout development which distinctly differ from the known gout risk loci that basically elevate serum uric acid level.

Conclusions

This meta-analysis is the first to reveal the loci associated with crystal-induced inflammation, the last step in gout development that aggravates AHUA into gout. Our findings should help to elucidate the molecular mechanisms of gout development and assist the prevention of gout attacks in high-risk AHUA individuals.

Oral administration of Domain-I of beta-2glycoprotein-I induces immunological tolerance in experimental murine antiphospholipid syndrome

It is well established that the humoral immunity in antiphospholipid syndrome (APS) is presented by circulating pathogenic anti-β2GPI autoantibodies targeting mainly domain I of the β2GPI protein, playing a major role in the disease pathogenesis. Previously, we have demonstrated that treatment of experimental APS mice with tolerogenic dendritic cells loaded with domain-I was more efficient in tolerance induction than with the whole molecule or domain-V. In the current study we had orally administered a domain-I derivative of the β2GPI molecule, as a new therapeutic approach to induce oral tolerance in this mouse model of APS. BALB/c mice immunized with β2GPI, were fed with either domain-I, domain-V derivative or the complete β2GPI protein. β2GPI immunized mice developed experimental APS which were fed with domain-I significantly had decreased fetal loss (p < 0.004), a lower size of thrombi (p < 0.001) and lower circulating anti-β2GPI Abs in comparison to mice fed with domain-V or PBS (p < 0.002). Likewise, Domain-I fed mice had a lowered inflammatory response, exhibited by decreased expression of inflammatory cytokines (IFNγ, IL-6, IL-17) and elevated production of IL-10 anti-inflammatory cytokine by splenocytes. Moreover, the anti-inflammatory response in the domain-I fed APS mice was associated with increased circulating miRNA variations (155, 146, 182, 98) by RT-PCR, which are associated with immunomodulation of the immune network. We propose that oral tolerance with domain-I can be a novel therapy for patients with APS.

Ferritin heavy subunit enhances apoptosis of non-small cell lung cancer cells through modulation of miR-125b/p53 axis

Ferritin is a nanocage protein composed by the variable assembly of 24 heavy and light subunits. As major intracellular iron storage protein, ferritin has been studied for many years in the context of iron metabolism. However, recent evidences have highlighted its role, in particular that of the heavy subunit (FHC), in pathways related to cancer development and progression, such as cell proliferation, growth suppressor evasion, cell death inhibition, and angiogenesis. At least partly, the involvement in these pathways is due to the ability of FHC to control the expression of a repertoire of oncogenes and oncomiRNAs. Moreover, the existence of a feedback loop between FHC and the tumor suppressor p53 has been demonstrated in different cell types. Here, we show that ectopic over-expression of FHC induces the promoter hypermethylation and the down-regulation of miR-125b that, in turn, enhances p53 protein expression in non-small cell lung cancer (NSCLC) cell lines. Notably, analysis by absolute quantitative RT-PCR of FHC, miR-125b, and p53 strongly suggests that this axis might be active in human NSCLC tissue specimens. In vitro, FHC over-expression attenuates survival of NSCLC cells by inducing p53-mediated intrinsic apoptosis that is partially abrogated upon miR-125b re-expression. Overall, our findings demonstrate that FHC acts as a tumor suppressor gene, thus providing a potential molecular strategy for induction of NSCLC apoptotic cell death.

Evaluation of plasma microRNA expressions in patients with juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic disease of childhood, yet its etiology is unknown. It is known that microribonucleic acids (miRNAs) play a role in immunoregulation. We aimed to evaluate the plasma expression of some candidate miRNAs that are associated with the pathogenesis of autoimmunity. Thirty-one patients diagnosed with JIA and age-sex-matched 31 healthy children were enrolled for the study. The plasma levels of four candidate miRNAs (miRNA-16, miRNA-155, miRNA-204, and miRNA-451), which are known to be associated with autoimmunity, were examined in all the subjects. The plasma levels of miRNAs were measured with real-time PCR in the patients in active and inactive periods and in the healthy controls. The groups were compared with each other. The plasma miRNA-155 levels were found to increase in the JIA patients compared to the healthy controls, and it was statistically more significant in the inactive period. We found that the JIA patients had the higher levels of miRNA-16 and the lower levels of miRNA-204/miRNA-451 expressions compare with the control group, but there was no statistically significant difference. A statistically significant decrease in the plasma levels of miRNA-204 was found in the patients that were in inactive disease with only methotrexate therapy. The plasma miRNA expressions were compared in the JIA subtypes, and it was observed that miRNA-204 levels were higher in polyarticular JIA and miRNA-451 levels were higher in enthesitis-related arthritis without statistical significance. The significant alterations in the plasma expression of miRNA-155 and miRNA-204 suggest to us that these molecules may be related to the pathogenesis of JIA. More comprehensive and functional researches about the role of these molecules are needed in this regard.

Calcium Oxalate Differentiates Human Monocytes Into Inflammatory M1 Macrophages

Purpose

A number of hyperoxaluric states have been associated with calcium oxalate (CaOx) deposits in the kidneys. In animal models of stone disease, these crystals interact with circulating monocytes that have migrated into the kidney as part of innate immunity. Similarly, macrophages surround CaOx crystals in kidneys of patients excreting high levels of oxalate. We investigate the effect of this exposure and subsequent human immunological response in vitro.

Materials and methods

Primary human monocytes were collected from healthy donors and exposed to CaOx, potassium oxalate, and zinc oxalate (ZnOx). Cytokine production was measured with a multiplex ELISA. Quantitative reverse transcription-polymerase chain reaction was done to validate the mRNA profile expression. M1 macrophage phenotype was confirmed with immunofluorescence microscopy.

Results

Both primary monocytes and THP-1 cells, a human monocytic cell line, respond strongly to CaOx crystals in a dose-dependent manner producing TNF-α, IL-1β, IL-8, and IL-10 transcripts. Exposure to CaOx followed by 1 h with LPS had an additive effect for cytokine production compared to LPS alone, however, LPS followed by CaOx led to significant decrease in cytokine production. Supernatants taken from monocytes were previously exposed to CaOx crystals enhance M2 macrophage crystal phagocytosis. CaOx, but not potassium or ZnOx, promotes monocyte differentiation into inflammatory M1-like macrophages.

Conclusion

In our in vitro experiment, human monocytes were activated by CaOx and produced inflammatory cytokines. Monocytes recognized CaOx crystals through a specific mechanism that can enhance or decrease the innate immune response to LPS. CaOx promoted M1 macrophage development. These results suggest that monocytes have an important role promoting CaOx-induced inflammation.

MicroRNA expression in the affected skin of adult patients with IgA vasculitis

IgA vasculitis (IgAV) represents a common systemic vasculitis in pediatric and adult population. Our current knowledge of disease pathogenesis is still very limited, without information on miRNAs in IgAV. The aim of our study was to determine the expression of five pre-selected miRNAs (miRNA-146a-5p, miRNA-148-3p, miRNA-155-5p, miRNA-223-3p, and let-7b) in the affected skin of adult IgAV patients. The study included 65 skin samples from consecutive, untreated IgAV patients (61.5% male, median age 67.6 years, range 29-91), diagnosed between October 2014 and September 2016, and 20 samples of normal skin from healthy volunteers. Total RNA was isolated from tissue sections of formalin-fixed, paraffin-embedded samples. Expression of miRNAs was measured using qRT-PCR. To present relative miRNA expression, the ΔΔCT method was used. Skin miRNA expression was correlated to clinical characteristics of adult IgAV patients. We found significantly higher levels of miRNA-155-5p, miRNA-223-3p, and let-7b in the affected skin compared to controls (18.6-fold, 6.4-fold, and 7.9-fold higher respectively). Contrary, the miRNA 148-3p expression was significantly lower (2.2-fold). The expression of the miRNA-146-5p showed near normal levels. Patients with necrotic skin lesions had significantly higher miRNA-223 tissue expression than those with non-necrotic purpura (p = 0.029). Gastrointestinal tract involvement inversely correlated with the expression of miRNA-155-5p and/or miRNA-146a-5p in affected skin. Altered expression of miRNA-148b-3p, miRNA-155-5p, miRNA-223-3p, and let-7b was found in vasculitic skin lesions in IgAV. Additionally, we found a positive association between the severity of purpura and skin miRNA-223-3p expression. Aberrantly expressed miRNAs could represent a biomarker in adult IgAV.

miR-20a inhibition using locked nucleic acid (LNA) technology and its effects on apoptosis of human macrophages infected by Toxoplasma gondii RH strain

Toxoplasma gondii is a ubiquitous and infectious parasite that multiplies in any nucleated cell of warm-blooded animals and humans worldwide. This parasite has intricate mechanisms to reciprocate host-cell apoptosis to exist in the host cell. So far, the details of the parasite interactions with host cells are not well known. MicroRNAs (miRNAs) are one of the small noncoding RNAs that are now considered as a key mechanism of gene regulation. They are important in physiological and pathological processes such as apoptosis. In this study a Real Time quantitative PCR technique was used to evaluate the levels of miR-20a of miRNAs family in human macrophage during T. gondii infection to determine the role of miR-20a in apoptosis. Then, the inhibition of miR-20a function through interaction with transfection of Locked Nucleic Acid (LNA) antisense oligomer was studied. Furthermore, it was examined whether miR-20a is involved in apoptosis of human macrophages with T. gondii infected cells using flow cytometry. We found that miR-20a expression is up-regulated in human macrophages following T. gondii infection. After LNA anti miR-20a oligomer transfection, miR-20a inhibition was evaluated by quantitative reverse transcriptase polymerase chain reaction. Flow cytometry results showed that LNA anti-miR20a oligomer increased apoptosis. In agreement with this result, we found that specific LNA oligonucleotides prevent the functional activity of miR-20a and promotion of human macrophages apoptosis with T. gondii infection by inhibition of this miRNAs gene. Also, the results support the concept that LNA oligomer antisense may be used as a therapeutic implement for blocking detrimental miRNAs overexpressed in infections.

From blood coagulation to innate and adaptive immunity: the role of platelets in the physiology and pathology of autoimmune disorders

Thrombosis and cardiovascular complications are common manifestations of a variety of pathological conditions, including infections and chronic inflammatory diseases. Hence, there is great interest in determining the hitherto unforeseen immune role of the main blood coagulation executor-the platelet. Platelets store and release a plethora of immunoactive molecules, generate microparticles, and interact with cells classically belonging to the immune system. The observed effects of platelet involvement in immune processes, especially in autoimmune diseases, are conflicting-from inciting inflammation to mediating its resolution. An in-depth understanding of the role of platelets in inflammation and immunity could open new therapeutic pathways for patients with autoimmune disorders. This review aims to summarize the current knowledge on the role of platelets in the patomechanisms of autoimmune disorders and suggests directions for future research.

Novel Triazole linked 2-phenyl benzoxazole derivatives induce apoptosis by inhibiting miR-2, miR-13 and miR-14 function in Drosophila melanogaster

Apoptosis is an important phenomenon in multi cellular organisms for maintaining tissue homeostasis and embryonic development. Defect in apoptosis leads to a number of disorders like- autoimmune disorder, immunodeficiency and cancer. 21-22 nucleotides containing micro RNAs (miRNAs/miRs) function as a crucial regulator of apoptosis alike other cellular pathways. Recently, small molecules have been identified as a potent inducer of apoptosis. In this study, we have identified novel Triazole linked 2-phenyl benzoxazole derivatives (13j and 13h) as a negative regulator of apoptosis inhibiting micro RNAs (miR-2, miR-13 and miR-14) in a well established in vivo model Drosophila melanogaster where the process of apoptosis is very similar to human apoptosis. These compounds inhibit miR-2, miR-13 and miR-14 activity at their target sites, which induce an increased caspase activity, and in turn influence the caspase dependent apoptotic pathway. These two compounds also increase the mitochondrial reactive oxygen species (ROS) level to trigger apoptotic cell death.

Altered Expression of MicroRNAs in Rheumatoid Arthritis

Rheumatoid arthritis is one of the most common types of inflammatory joint diseases. Women, smokers, and people with positive family history are more susceptible to this disease. Diagnostic criteria include at least one swollen joint that has not been caused by other diseases. MicroRNAs are non-coding RNAs that are evolutionarily conserved and have a length of 18-25 nucleotides. MicroRNAs control gene expression at the post-transcriptional level via promoting mRNA degradation or translational repression. Recognition of alterations in microRNA status and their respective targets, may offer an opportunity to better identify the pathways that are involved in the etiopathogenesis of autoimmune diseases. It has been suggested that microRNAs may serve as potential biomarkers for both diagnosis and prognosis of autoimmune diseases. Here, we review the available evidence on the deregulations of microRNA expression in rheumatoid arthritis. More precisely, this review focuses on the microRNA involved in T cell regulation and gives perspectives on the use of this microRNA as biomarkers of diagnosis, prognosis, or intervention efficacy. J. Cell. Biochem. 119: 478-487, 2018. © 2017 Wiley Periodicals, Inc.

Upregulation of circulating microRNA-134 in adult-onset Still's disease and its use as potential biomarker

Adult-onset Still’s disease (AOSD) is a multi-systemic inflammatory disorder of unknown etiology. To date, no single diagnostic test is available for AOSD. Herein, we investigated the pathogenic role of microRNAs in AOSD. MicroRNA profiles in plasma from AOSD patients and healthy controls were analyzed by microarray analysis, followed by quantitative reverse transcription PCR validation. The biological functions of microRNAs were evaluated using in vitro cell-based assay. Among the differentially expressed microRNAs, microRNA-134 (miR-134) expression was positively correlated with AOSD activity scores and significantly decreased after effective treatment. An increased miR-134 level is significantly associated with the activation of Toll-like receptor 3 (TLR3). The reporter assay identified IL-18 binding protein (IL-18BP) as the target of miR-134. A negative correlation between miR-134 expression and IL-18BP mRNA levels were detected in peripheral blood cells following TLR3 ligand treatment. Lower plasma IL-18BP levels and higher IL-18 levels were also observed in active AOSD patients who had higher miR-134 expression than inactive patients. Upregulation of circulating miR-134 was associated with elevated IL-18 levels by targeting IL-18BP in AOSD patients and was positively correlated with disease activity, suggesting its involvement in AOSD pathogenesis. MiR-134 may be a novel activity indicator or potential prognostic biomarker in AOSD.

Identification of synovial fluid microRNA signature in knee osteoarthritis: differentiating early- and late-stage knee osteoarthritis

OBJECTIVES

This study aimed to identify circulating microRNA (miRNA) signatures in knee synovial fluid (SF) from early-stage and late-stage knee osteoarthritis (OA) patients.

METHODS

miRNAs were screened by miRNA-PCR-arrays and validated by Real-time quantitative polymerase chain reaction (RT-qPCR) in SF from early-stage (Kellgren-Lawrence (KL): Grade: I/II) and late-stage OA patients (Grade: III/IV). OA cartilage or synovial explants were cultured to study the source/release of identified miRNAs. Computational-approach was utilized to predict gene/pathway targets.

RESULTS

Our screening/validation analysis identified a panel of seven (out of 752) circulating miRNAs (23a-3p, 24-3p, 27a-3p, 27b-3p, 29c-3p, 34a-5p and 186-5p) that were significantly differentially expressed in late-stage vs early-stage OA-SF, irrespective of age, gender and Body Mass Index (BMI). miR-378a-5p was mostly detectable in majority of late-stage OA-SF. Cartilage explants stimulated with IL-1β showed a significant reduction in miR-23a-3p, 27a-3p and 27b-3p expression with no significant changes in other validated miRNAs. However, IL-1β-stimulated OA synovial explants exhibited significantly increased expression of miR-23a-3p, 24-3p, 27a-3p, 27b-3p, 29c-3p, 186-5p and 378a-5p, and release of only 23a-3p and 27b-3p in supernatants, suggesting that IL-1β contributes to the release of 23a-3p and 27b-3p into the SF from synovium. Computational-analysis identified 2 genes (ROQUIN-1 [RC3H1] and quaking-gene [QKI]) that are targeted by six out of eight miRNAs; miR-27b-3p exhibited greatest association with RC3H1 and QKI genes. Indeed, synovial explants treated with miR-27b-3p-mimic show significant suppression of both RC3H1 and QKI genes.

CONCLUSIONS

We provide first evidence of the differential expression of circulating miRNAs in early-stage vs late-stage knee OA-SF. Further, we provide source, release and genes/pathways regulated by identified miRNAs.

Can baseline serum microRNAs predict response to TNF-alpha inhibitors in rheumatoid arthritis?

BACKGROUND

In rheumatoid arthritis, prediction of response to TNF-alpha inhibitor (TNFi) treatment would be of clinical value. This study aims to discover miRNAs that predict response and aims to replicate results of two previous studies addressing this topic.

METHODS

From the observational BiOCURA cohort, 40 adalimumab- (ADA) and 40 etanercept- (ETN) treated patients were selected to enter the discovery cohort and baseline serum profiling on 758 miRNAs was performed. The added value of univariately selected miRNAs (p < 0.05) over clinical parameters in prediction of response was determined by means of the area under the receiver operating characteristic curve (AUC-ROC). Validation was performed by TaqMan single qPCR assays in 40 new patients.

RESULTS

Expression of miR-99a and miR-143 predicted response to ADA, and miR-23a and miR-197 predicted response to ETN. The addition of miRNAs increased the AUC-ROC of a model containing only clinical parameters for ADA (0.75 to 0.97) and ETN (0.68 to 0.78). In validation, none of the selected miRNAs significantly predicted response. miR-23a was the only overlapping miRNA compared to the two previous studies, however inversely related with response in one of these studies. The reasons for the inability to replicate previously proposed miRNAs predicting response to TNFi and replicate those from the discovery cohort were investigated and discussed.

CONCLUSIONS

To date, no miRNA consistently predicting response to TNFi therapy in RA has been identified. Future studies on this topic should meet a minimum of standards in design that are addressed in this study, in order to increase the reproducibility.

MicroRNA-375 as a biomarker for malignant transformation in oral lesions

OBJECTIVE

Malignant transformation of oral premalignant lesions is the key process in the progression to oral squamous cell carcinoma (OSCC). Previously, we identified miR-7 and miR-21 as candidate oncogenes and miR-375 and miR-494 as candidate tumor suppressors in OSCC. We aim to evaluate these microRNAs as biomarkers of malignant transformation in oral premalignant lesions.

STUDY DESIGN

Formalin-fixed, paraffin-embedded samples from progressive premalignant lesions and paired sequential OSCC tumors at the same site were obtained from same patients (n = 31). Total RNA was extracted and analyzed for microRNA levels using real-time polymerase chain reaction.

RESULTS

MiR-375 expression in progressive lesions was clearly lower than in nonprogressive control lesions (average eightfold difference, P = .0004). Furthermore, the expression of miR-375 decreased significantly after the progression from premalignant lesion to OSCC (P < .0001). Receiver operating characteristic curve analysis revealed that miR-375 was able to differentiate between progressive and nonprogressive premalignant lesions (P < .0001).

CONCLUSIONS

MiR-375 downregulation in oral premalignant lesions is associated with a higher risk of malignant transformation.

Familial Mediterranean fever: current perspectives

Familial Mediterranean fever (FMF) is the most frequent monogenic autoinflammatory disease, and it is characterized by recurrent attacks of fever and polyserositis. The disease is associated with mutations in the MEFV gene encoding pyrin, which causes exaggerated inflammatory response through uncontrolled production of interleukin 1. The major long-term complication of FMF is amyloidosis. Colchicine remains the principle therapy, and the aim of treatment is to prevent acute attacks and the consequences of chronic inflammation. With the evolution in the concepts about the etiopathogenesis and genetics of the disease, we have understood that FMF is more complicated than an ordinary autosomal recessive monogenic disorder. Recently, recommendation sets have been generated for interpretation of genetic testing and genetic diagnosis of FMF. Here, we have reviewed the current perspectives in FMF in light of recent recommendations.

RBM3 regulates temperature sensitive miR-142-5p and miR-143 (thermomiRs), which target immune genes and control fever

Fever is commonly used to diagnose disease and is consistently associated with increased mortality in critically ill patients. However, the molecular controls of elevated body temperature are poorly understood. We discovered that the expression of RNA-binding motif protein 3 (RBM3), known to respond to cold stress and to modulate microRNA (miRNA) expression, was reduced in 30 patients with fever, and in THP-1-derived macrophages maintained at a fever-like temperature (40°C). Notably, RBM3 expression is reduced during fever whether or not infection is demonstrable. Reduced RBM3 expression resulted in increased expression of RBM3-targeted temperature-sensitive miRNAs, we termed thermomiRs. ThermomiRs such as miR-142–5p and miR-143 in turn target endogenous pyrogens including IL-6, IL6ST, TLR2, PGE2 and TNF to complete a negative feedback mechanism, which may be crucial to prevent pathological hyperthermia. Using normal PBMCs that were exogenously exposed to fever-like temperature (40°C), we further demonstrate the trend by which decreased levels of RBM3 were associated with increased levels of miR-142–5p and miR-143 and vice versa over a 24 h time course. Collectively, our results indicate the existence of a negative feedback loop that regulates fever via reduced RBM3 levels and increased expression of miR-142–5p and miR-143.

A novel delivery platform based on Bacteriophage MS2 virus-like particles

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Here we reviewed Bacteriophage MS2 virus-like particles, including introduction to their structure, their potential as a delivery platform, and their expected use in medicine and other fields.

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Bacteriophage MS2 virus-like particles represent the novel delivery platform.

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Bacteriophage MS2 virus-like particles possess promising application prospect.

Our objective here is to review the novel delivery platform based on Bacteriophage MS2 virus-like particles (VLPs), including introduction to their structure, their potential as a delivery platform, and their expected use in medicine and other fields. Bacteriophage MS2 VLPs are nanoparticles devoid of viral genetic material and can self-assemble from the coat protein into an icosahedral capsid. As a novel delivery platform, they possess numerous features that make them suitable and attractive for targeted delivery of RNAs or DNAs, epitope peptides, and drugs within the protein capsid. In short, as a novel delivery platform, MS2 VLPs are suitable for delivery of targeted agents and hold promise for use in diagnostics, vaccines, and therapeutic modalities.

Idiopathic inflammatory myopathies: from immunopathogenesis to new therapeutic targets

Pathogenesis of idiopathic inflammatory myositis (IIM) involves strong interactions between dendritic cells (DCs), activated Th1 and Th17 cells, B cells, muscle cells, genes and environment. Local maturation of DCs permit the activation and polarization of CD4+ T cells into T(H)1 and T(H)17 that play a key role in maintaining chronic muscle inflammation. T-cell mediated myocytotoxicity promotes the liberation of specific muscle autoantigens from regenerating muscle cells with production of myositis-specific autoantibodies. Type I interferon signature is a key characteristic of IIM. Type I IFN that can be induced by immune complexes containing myositis-specific autoantibodies is produced by scattered plasmacytoid DCs but also by muscle cells particularly regenerating muscle cells. These immature muscle precursors appear to be critical in the pathogenesis of IIM as they up-regulate muscle autoantigens, type I IFN, HLA class I antigens and TLR3-7, all together involved in maintaining chronic muscle inflammation. In addition to the role of immune and muscle cells, genome-wide association studies have confirmed the importance of several MHC and non-MHC genes in IIM. Environmental factors can contribute to the pathogenesis of IIM. In sIBM, distinct features suggest both degenerative and inflammatory processes. In addition to our better understanding of the pathogenesis, identify molecular pathway leads to consider new targeted therapies including cytokine inhibition, B-cell and T-cell costimulation blockade, type I IFN neutralization or inhibition of the ubiquitin proteasome pathway.

Bioinformatics-Based Identification of MicroRNA-Regulated and Rheumatoid Arthritis-Associated Genes

MicroRNAs (miRNAs) act as epigenetic markers and regulate the expression of their target genes, including those characterized as regulators in autoimmune diseases. Rheumatoid arthritis (RA) is one of the most common autoimmune diseases. The potential roles of miRNA-regulated genes in RA pathogenesis have greatly aroused the interest of clinicians and researchers in recent years. In the current study, RA-related miRNAs records were obtained from PubMed through conditional literature retrieval. After analyzing the selected records, miRNA targeted genes were predicted. We identified 14 RA-associated miRNAs, and their sub-analysis in 5 microarray or RNA sequencing (RNA-seq) datasets was performed. The microarray and RNA-seq data of RA were also downloaded from NCBI Gene Expression Omnibus (GEO) and Sequence Read Archive (SRA), analyzed, and annotated. Using a bioinformatics approach, we identified a series of differentially expressed genes (DEGs) by comparing studies on RA and the controls. The RA-related gene expression profile was thus obtained and the expression of miRNA-regulated genes was analyzed. After functional annotation analysis, we found GO molecular function (MF) terms significantly enriched in calcium ion binding (GO: 0005509). Moreover, some novel dysregulated target genes were identified in RA through integrated analysis of miRNA/mRNA expression. The result revealed that the expression of a number of genes, including ROR2, ABI3BP, SMOC2, etc., was not only affected by dysregulated miRNAs, but also altered in RA. Our findings indicate that there is a close association between negatively correlated mRNA/miRNA pairs and RA. These findings may be applied to identify genetic markers for RA diagnosis and treatment in the future.

MicroRNA regulation of viral immunity, latency, and carcinogenesis of selected tumor viruses and HIV

MicroRNAs (miRNAs) function as key regulators in immune responses and cancer development. In the contexts of infection with oncogenic viruses, miRNAs are engaged in viral persistence, latency establishment and maintenance, and oncogenesis. In this review, we summarize the potential roles and mechanisms of viral and cellular miRNAs in the host-pathogen interactions during infection with selected tumor viruses and HIV, which include (i) repressing viral replication and facilitating latency establishment by targeting viral transcripts, (ii) evading innate and adaptive immune responses via toll-like receptors, RIG-I-like receptors, T-cell receptor, and B-cell receptor pathways by targeting signaling molecules such as TRAF6, IRAK1, IKKε, and MyD88, as well as downstream targets including regulatory cytokines such as tumor necrosis factor α, interferon γ, interleukin 10, and transforming growth factor β, (iii) antagonizing intrinsic and extrinsic apoptosis pathways by targeting pro-apoptotic or anti-apoptotic gene transcripts such as the Bcl-2 family and caspase-3, (iv) modulating cell proliferation and survival through regulation of the Wnt, PI3K/Akt, Erk/MAPK, and Jak/STAT signaling pathways, as well as the signaling pathways triggered by viral oncoproteins such as Epstein-Barr Virus LMP1, by targeting Wnt-inhibiting factor 1, SHIP, pTEN, and SOCSs, and (v) regulating cell cycle progression by targeting cell cycle inhibitors such as p21/WAF1 and p27/KIP1. Further elucidation of the interaction between miRNAs and these key biological events will facilitate our understanding of the pathogenesis of viral latency and oncogenesis and may lead to the identification of miRNAs as novel targets for developing new therapeutic or preventive interventions.

MicroRNAs in skin tissue engineering

35.2 million annual cases in the U.S. require clinical intervention for major skin loss. To meet this demand, the field of skin tissue engineering has grown rapidly over the past 40 years. Traditionally, skin tissue engineering relies on the "cell-scaffold-signal" approach, whereby isolated cells are formulated into a three-dimensional substrate matrix, or scaffold, and exposed to the proper molecular, physical, and/or electrical signals to encourage growth and differentiation. However, clinically available bioengineered skin equivalents (BSEs) suffer from a number of drawbacks, including time required to generate autologous BSEs, poor allogeneic BSE survival, and physical limitations such as mass transfer issues. Additionally, different types of skin wounds require different BSE designs. MicroRNA has recently emerged as a new and exciting field of RNA interference that can overcome the barriers of BSE design. MicroRNA can regulate cellular behavior, change the bioactive milieu of the skin, and be delivered to skin tissue in a number of ways. While it is still in its infancy, the use of microRNAs in skin tissue engineering offers the opportunity to both enhance and expand a field for which there is still a vast unmet clinical need. Here we give a review of skin tissue engineering, focusing on the important cellular processes, bioactive mediators, and scaffolds. We further discuss potential microRNA targets for each individual component, and we conclude with possible future applications.

MicroRNAs dysregulation in hepatocellular carcinoma: Insights in genomic medicine

Hepatocellular carcinoma (HCC) is the leading primary liver cancer and its clinical outcome is still poor. MicroRNAs (miRNAs) have demonstrated an interesting potential to regulate gene expression at post-transcriptional level. Current findings suggest that miRNAs deregulation in cancer is caused by genetic and/or epigenetic, transcriptional and post-transcriptional modifications resulting in abnormal expression and hallmarks of malignant transformation: aberrant cell growth, cell death, differentiation, angiogenesis, invasion and metástasis. The important role of miRNAs in the development and progression of HCC has increased the efforts to understand and develop mechanisms of control overt this single-stranded RNAs. Several studies have analyzed tumoral response to the regulation and control of deregulated miRNAs with good results in vitro and in vivo, proving that targeting aberrant expression of miRNAs is a powerful anticancer therapeutic. Identification of up and/or down regulated miRNAs related to HCC has led to the discovery of new potential application for detection of their presence in the affected organism. MiRNAs represent a relevant new target for diagnosis, prognosis and treatment in a wide variety of pathologic entities, including HCC. This manuscript intends to summarize current knowledge regarding miRNAs and their role in HCC development.