Plasma microRNA expression profiles in Chinese patients with rheumatoid arthritis

miRNAs and NFKB1 and TRAF6 target genes: The initial functional study in CD14+ monocytes in rheumatoid arthritis patients

We predicted miRNAs with regulatory impact on NFKB1 and TRAF6 gene expression and selected the miR-194-5p, miR-124-3p, miR-9-5p, and miR-340-5p and their target genes for expression analyses on CD14+ monocytes from rheumatoid arthritis (RA) patients and healthy controls. Additionally, we evaluated the influence of genes and miRNA expression on RA patients' cytokine levels. No difference was observed in genes or miRNAs expression when compared to healthy controls and RA patients or clinical parameters. However, we found a significant difference between miR-194-5p and miR-9-5p levels (FC=-2.31; p=0.031; FC=-3.05;p=0.031, respectively) and non-prednisone users as compared to prednisone using patients. We conducted correlation analyses to identify the strength of the relationship between expression data and cytokine plasma levels. We observed a moderate positive correlation between miR-124-3p expression and IL-6 plasma levels (r=0.46; p=0.033). In addition, overexpression of miRNAs was concomitant to TRAF6 and NFKB1 genes as indicated by correlation analyses: TRAF6 and miR-194-5p (r=0.60;p<0.001) and miR-9-5p (r=0.63;p<0.001) and NFKB1 and miR-194-5p (r=0.72;p<0.001), miR-9-5p (r=0.72;p<0.001) and miR-340-5p (r=0.61;p<0.001). NFKB1 and TRAF6 genes and miRNAs monocyte expression do not appear to be related to RA but showed a significant difference in different groups of RA therapy. In addition, increased levels of miRNAs can be linked to concomitant overexpression of TRAF6 and NFKB1 in monocytes and act as its regulators.

Plasma circulating microRNAs associated with blood-based immune markers: a population-based study

MicroRNAs (miRNAs) are small non-coding RNAs that post-transcriptionally regulate gene expression and different immune-related pathways. There is a great interest in identifying miRNAs involved in immune cell development and function to elucidate the biological mechanisms underlying the immune system, its regulation, and disease. In this study, we aimed to investigate the association of circulating miRNAs with blood cell compositions and blood-based immune markers. Circulating levels of 2083 miRNAs were measured by RNA-sequencing in plasma samples of 1999 participants from the population-based Rotterdam Study collected between 2002 and 2005. Full blood count measurements were performed for absolute granulocyte, platelet, lymphocyte, monocyte, white, and red blood cell counts. Multivariate analyses were performed to test the association of miRNAs with blood cell compositions and immune markers. We evaluated the overlap between predicted target genes of candidate miRNAs associated with immune markers and genes determining the blood immune response markers. First, principal component regression analysis showed that plasma levels of circulating miRNAs were significantly associated with red blood cell, granulocyte, and lymphocyte counts. Second, the cross-sectional analysis identified 210 miRNAs significantly associated (P < 2.82 × 10-5) with neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammation index. Further genetic look-ups showed that target genes of seven identified miRNAs (miR-1233-3p, miR-149-3p, miR-150-5p, miR-342-3p, miR-34b-3p, miR-4644, and miR-7106-5p) were also previously linked to NLR and PLR markers. Collectively, our study suggests several circulating miRNAs that regulate the innate and adaptive immune systems, providing insight into the pathogenesis of miRNAs in immune-related diseases and paving the way for future clinical applications.

Plasma Expression of Carotid Plaque Presence-Related MicroRNAs Is Associated with Inflammation in Patients with Rheumatoid Arthritis

Rheumatoid arthritis (RA) is associated with problems beyond the joints such as cardiovascular (CV) disease. MicroRNA-24, -146 and -Let7a are associated with carotid plaque presence in RA patients. We evaluated whether these microRNAs were involved in the inflammatory state of RA, and we studied their gene targets to understand their role in inflammation and atherosclerosis. A total of 199 patients with RA were included. Inflammatory variables such as disease activity score 28 (DAS28) and erythrocyte sedimentation rate (ESR) were quantified. MicroRNAs were extracted from plasma and quantified with qPCR. Multivariate models and classification methods were used for analysis. The multivariate models showed that diminished expression of microRNA-146 was associated with inferior levels of DAS28-ESR, and the decreased expression of microRNA-24, -146 and -Let7a were associated with lowered ESR in the overall cohort. When microRNAs were evaluated globally, a global increase was associated with increased DAS28-ESR and ESR in the overall cohort. Sex-stratified analyses showed different associations of these microRNAs with the inflammatory variables. Finally, random forest models showed that microRNAs have a pivotal role in classifying patients with high and low inflammation. Plasmatic expressions of microRNA-24, -146 and -Let7a were associated with inflammatory markers of RA. These microRNAs are associated with both inflammation and atherosclerosis and are potential therapeutic targets for RA.

Serum miR-342-3p Acts as a Biomarker for Systemic Lupus Erythematosus and Participates in the Disease Progression

Purpose

The aim of this study was to investigate the diagnostic ability and prognostic value of miR-342-3p in SLE patients by detecting the expression level of serum miR-342-3p in SLE patients.

Patients and Methods

The expression level of serum miR-342-3p in all subjects was determined by qRT-PCR technology, and the correlation of miR-342-3p with SLEDAI scores was evaluated using Spearman correlation coefficient. The diagnostic value of miR-342-3p in SLE was assessed using ROC curve. The prognostic value of miR-342-3p in SLE patients was analyzed by Kaplan-Meier survival curve and multivariate COX regression.

Results

The qRT-PCR results showed that the expression level of serum miR-342-3p in SLE patients was significantly lower than that in healthy controls (P < 0.001). Serum miR-342-3p expression level was negatively correlated with SLEDAI scores (r = - 0.810, P < 0.001). The ROC curve suggested that serum miR-342-3p expression level was discriminative between SLE patients and healthy controls. Survival analysis results indicated that SLE patients with low serum miR-342-3p expression had a higher probability of poor prognosis of SLE (Log rank P = 0.003).

Conclusion

The expression level of serum miR-342-3p was valuable in the diagnosis of SLE. Meanwhile, the low expression level of serum miR-342-3p was associated with the poor prognosis of SLE.

Non-coding RNAs in immunoregulation and autoimmunity: Technological advances and critical limitations

Immune cell function is critically dependent on precise control over transcriptional output from the genome. In this respect, integration of environmental signals that regulate gene expression, specifically by transcription factors, enhancer DNA elements, genome topography and non-coding RNAs (ncRNAs), are key components. The first three have been extensively investigated. Even though non-coding RNAs represent the vast majority of cellular RNA species, this class of RNA remains historically understudied. This is partly because of a lag in technological and bioinformatic innovations specifically capable of identifying and accurately measuring their expression. Nevertheless, recent progress in this domain has enabled a profusion of publications identifying novel sub-types of ncRNAs and studies directly addressing the function of ncRNAs in human health and disease. Many ncRNAs, including circular and enhancer RNAs, have now been demonstrated to play key functions in the regulation of immune cells and to show associations with immune-mediated diseases. Some ncRNAs may function as biomarkers of disease, aiding in diagnostics and in estimating response to treatment, while others may play a direct role in the pathogenesis of disease. Importantly, some are relatively stable and are amenable to therapeutic targeting, for example through gene therapy. Here, we provide an overview of ncRNAs and review technological advances that enable their study and hold substantial promise for the future. We provide context-specific examples by examining the associations of ncRNAs with four prototypical human autoimmune diseases, specifically rheumatoid arthritis, psoriasis, inflammatory bowel disease and multiple sclerosis. We anticipate that the utility and mechanistic roles of these ncRNAs in autoimmunity will be further elucidated in the near future.

[Expression of miR-342-3p in rheumatoid arthritis patients and its effect on synovial fibroblast inflammation and migration]

OBJECTIVE

To investigate the expression level of miR-342-3p in peripheral blood mononuclear cells (PBMCs) of patients with rheumatoid arthritis (RA) and its effect on inflammatory response and migration of synovial fibroblasts in RA (RA-FLS).

METHODS

PBMCs were collected from 30 healthy individuals and 50 RA patients for detecting the expression of miR-342-3p, and its correlation with the clinical indicators RF, ESR, anti-CCP, hs-CRP, C3, DAS-28, SAS, and SDS was analyzed. In RA-FLS cultures, the effect of transfection of miR-342-3p mimics and inhibitor on TNF-α-induced inflammatory response of the cells was evaluated by detecting the expressions of IL-1β, IL-6, IL-10, and TNF-α using ELISA. CCK8 assay and Transwell assay were used for detecting the changes in cell viability and migration ability of the synovial cells.

RESULTS

In RA patients, the expression level of miR-342-3p was significantly lowered in the PBMCs (P < 0.05) with an area under the ROC curve of 97.53% and showed inverse correlations with RF (r=-0.321), ESR(r=-0.284), anti-CCP (r=-0.355), hs-CRP (r=-0.320), C3 (r=-0.294), DAS-28 (r=-0.395), SAS (r=-0.366), and SDS (r=-0.397) (all P < 0.05); a low expression of miR-342-3p was strongly associated with elevated levels of anti-CCP, DAS-28, SDS, and SAS (all with a rule support greater than 85%, confidence greater than 88%, and lift greater than 1). In cultured RA-FLS, TNF-α stimulation significantly increased the cell viability (P < 0.05), upregulated the expressions of IL-1β, IL-6, and TNF-α, and lowered the expression of IL-10 (P < 0.05). These changes were significantly suppressed by transfection of the cells with miR-342-3p mimics (P < 0.05) but enhanced by transfection with miR-342-3p inhibitor (P < 0.05).

CONCLUSION

The expression of miR-342-3p is decreased in the PBMCs of RA patients. A lowered expression of miR-342-3p contributes to the pathogenesis of RA by promoting inflammatory responses and migration of RA-FLS.

MicroRNA-122-3p plays as the target of long non-coding RNA LINC00665 in repressing the progress of arthritis

MicroRNAs (miRNAs) play important roles in many diseases, including rheumatoid arthritis (RA). However, the mechanisms underlying the effects of miR-122-3p-3p on RA are not distinct and require further investigation. Patients with RA and healthy controls were recruited to analyze the miR-122-3p levels. The MH7A cells were stimulated with interleukin (IL)-1β to mimic the local inflammation of RA. Cell Counting Kit-8 (CCK-8) and flow cytometry were performed to measure the viability and apoptosis of MH7A cells. Diana tools and TargetScan were used to predict the target relationships. Luciferase reporter assay was used to validate the target relationship. miR-122-3p is downregulated in RA patients and IL-1β-stimulated MH7A cells. miR-122-3p suppresses MH7A cell viability and promotes MH7A cell apoptosis. miR-122-3p targets LINC00665. LINC00665 eliminates the inhibitory effect of miR-122-3p on IL-1β-stimulated MH7A cells. Eukaryotic translation initiation factor 2 alpha kinase 1 (EIF2AK1) targets miR-122-3p. In addition, EIF2AK1 is highly expressed in patients with RA. In addition, EIF2AK1 activates the mTOR signaling pathway. miR-122-3p represses RA progression by reducing cell viability and increasing synoviocyte apoptosis.

Plasma miRNA Profile of Crohn's Disease and Rheumatoid Arthritis Patients

Crohn's disease (CD) and rheumatoid arthritis (RA) are immune mediated inflammatory diseases. Several studies indicate a role for microRNAs (miRNAs) in the pathogenesis of a variety of autoimmune diseases, including CD and RA. Our study's goal was to investigate circulating miRNAs in CD and RA patients to identify potential new biomarkers for early detection and personalized therapeutic approaches for autoimmune diseases. For this study, subjects with CD (n = 7), RA (n = 8) and healthy controls (n = 7) were recruited, and plasma was collected for miRNA sequencing. Comparison of the expression patterns of miRNAs between CD and healthy patients identified 99 differentially expressed miRNAs. Out of these miRNAs, 4 were down regulated, while 95 were up regulated. Comparison of miRNAs between RA and healthy patients identified 57 differentially expressed miRNAs. Out of those, 12 were down regulated, while 45 were up regulated. For all the miRNAs down regulated in CD and RA patients, 420 GO terms for biological processes were similarly regulated between both groups. Therefore, the identification of new plasma miRNAs allows the emergence of new biomarkers that can assist in the diagnosis and treatment of CD and RA.

MicroRNA-Mediated Epigenetic Regulation of Rheumatoid Arthritis Susceptibility and Pathogenesis

MicroRNAs (miRNAs) play crucial roles in regulating the transcriptome and development of rheumatoid arthritis (RA). Currently, a comprehensive map illustrating how miRNAs regulate transcripts, pathways, immune system differentiation, and their interactions with terminal cells such as fibroblast-like synoviocytes (FLS), immune-cells, osteoblasts, and osteoclasts are still laking. In this review, we summarize the roles of miRNAs in the susceptibility, pathogenesis, diagnosis, therapeutic intervention, and prognosis of RA. Numerous miRNAs are abnormally expressed in cells involved in RA and regulate target genes and pathways, including NF-κB, Fas-FasL, JAK-STAT, and mTOR pathways. We outline how functional genetic variants of miR-499 and miR-146a partly explain susceptibility to RA. By regulating gene expression, miRNAs affect T cell differentiation into diverse cell types, including Th17 and Treg cells, thus constituting promising gene therapy targets to modulate the immune system in RA. We summarize the diagnostic and prognostic potential of blood-circulating and cell-free miRNAs, highlighting the opportunity to combine these miRNAs with antibodies to cyclic citrullinated peptide (ACCP) to allow accurate diagnosis and prognosis, particularly for seronegative patients. Furthermore, we review the evidence implicating miRNAs as promising biomarkers of efficiency and response of, and resistance to, disease-modifying anti-rheumatic drugs and immunotherapy. Finally, we discuss the autotherapeutic effect of miRNA intervention as a step toward the development of miRNA-based anti-RA drugs. Collectively, the current evidence supports miRNAs as interesting targets to better understand the pathogenetic mechanisms of RA and design more efficient therapeutic interventions.

[Role of circular RNAs in immune-related diseases]

Objective Circular RNAs (circRNAs) are non-coding RNAs (ncRNA) circularized without a 3′ polyadenylation [poly-(A)] tail or a 5′ cap, resulting in a covalently closed loop structure. circRNAs were first discovered in RNA viruses in the 1970s, but only a small number of circRNAs were discovered at that time due to limitations in traditional polyadenylated transcriptome analyses. With the development of specific biochemical and computational methods, recent studies have shown the presence of abundant circRNAs in eukaryotic transcriptomes. circRNAs play vital roles in many physiological and pathological processes, such as acting as miRNA sponges, binding to RNA-binding proteins (RBPs), acting as transcriptional regulatory factors, and even serving as translation templates. Current evidence has shown that circRNAs can be potentially used as excellent biomarkers for diagnosis, therapeutic effect evaluation, and prognostic assessment of a variety of diseases, and they may also provide effective therapeutic targets due to their stability and tissue and development-stage specificity. This review focuses on the properties of circRNAs and their immune relationship to disease, and explores the role of circRNAs in immune-related diseases and the directions of future research.

Long non-coding RNA Xist contribution in systemic lupus erythematosus and rheumatoid arthritis

Growing evidence points towards the role of the long non-coding (lnc)-RNA Xist expressed in female cells as a predominant key actor for the sex bias observed in systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). Indeed, in female cells, lnc-Xist controls transcription directly by spreading across the inactivated X chromosome (Xi) and indirectly by sequestring miRNAs as a sponge. The inactivation process at Xi is altered in lymphocytes from SLE women and associated with important variations in ribonucleoproteins (RNP) associated with lnc-Xist. In fibroblast-like synoviocytes (FLS) and osteoclasts from RA women, proinflammatory and proliferative pathways are upregulated due to the sequestration effect exerted by lnc-Xist overexpression on miRNAs. The key role played by lnc-Xist in SLE and RA is further supported by it's knock down that recapitulates the SLE B cell extrafollicular profile and controls RA associated FLS proinflammatory cytokine production and proliferation.

ZFAS1 knockdown inhibits fibroblast-like synoviocyte proliferation, migration, invasion and inflammation, and promotes apoptosis via miR-3926/FSTL1 in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease characterized by joint disorders. Long non-coding RNA zinc finger antisense 1 (ZFAS1) is aberrantly expressed in numerous human diseases, including RA. The present study aimed to investigate the functions and underlying mechanisms of ZFAS1 in RA. Reverse transcription-quantitative PCR was performed to determine the expression levels of ZFAS1, microRNA (miR)-3926 and follistatin-like protein 1 (FSTL1). MTT assay, flow cytometric analysis and Transwell assay were performed to examine the proliferation, apoptosis, migration and invasion of fibroblast-like synoviocytes (FLSs), respectively. Western blotting was employed to measure the protein expression levels of cleaved caspase-3, interleukin (IL)-6, IL-1β, tumor necrosis factor-α and FSTL1. Dual-luciferase reporter assay was performed to verify the interaction between miR-3926 and ZFAS1 or FSTL1. The results demonstrated that ZFAS1 and FSTL1 were upregulated, and miR-3926 was downregulated in RA synovial tissues and RA-FLSs. ZFAS1 knockdown suppressed cell proliferation, migration, invasion and inflammatory cytokine production, and induced apoptosis in RA-FLSs. ZFAS1 acted as a sponge for miR-3926, and ZFAS1 overexpression abolished the impact of miR-3926 on the development of RA-FLSs. FSTL1 was a direct target of miR-3926, and the effect of FSTL1 knockdown on the progression of RA-FLSs was rescued by miR-3926 inhibition. Furthermore, ZFAS1 regulated FSTL1 expression levels via sponging miR-3926 in RA-FLSs. In conclusion, ZFAS1 knockdown inhibited RA-FLS proliferation, migration, invasion and inflammatory cytokine production, and induced apoptosis in RA via the miR-3926/FSTL1 axis.

The Expression of Non-Coding RNAs and Their Target Molecules in Rheumatoid Arthritis: A Molecular Basis for Rheumatoid Pathogenesis and Its Potential Clinical Applications

Rheumatoid arthritis (RA) is a typical autoimmune-mediated rheumatic disease presenting as a chronic synovitis in the joint. The chronic synovial inflammation is characterized by hyper-vascularity and extravasation of various immune-related cells to form lymphoid aggregates where an intimate cross-talk among innate and adaptive immune cells takes place. These interactions facilitate production of abundant proinflammatory cytokines, chemokines and growth factors for the proliferation/maturation/differentiation of B lymphocytes to become plasma cells. Finally, the autoantibodies against denatured immunoglobulin G (rheumatoid factors), EB virus nuclear antigens (EBNAs) and citrullinated protein (ACPAs) are produced to trigger the development of RA. Furthermore, it is documented that gene mutations, abnormal epigenetic regulation of peptidylarginine deiminase genes 2 and 4 (PADI2 and PADI4), and thereby the induced autoantibodies against PAD2 and PAD4 are implicated in ACPA production in RA patients. The aberrant expressions of non-coding RNAs (ncRNAs) including microRNAs (miRs) and long non-coding RNAs (lncRNAs) in the immune system undoubtedly derange the mRNA expressions of cytokines/chemokines/growth factors. In the present review, we will discuss in detail the expression of these ncRNAs and their target molecules participating in developing RA, and the potential biomarkers for the disease, its diagnosis, cardiovascular complications and therapeutic response. Finally, we propose some prospective investigations for unraveling the conundrums of rheumatoid pathogenesis.

Circulating status of microRNAs 660-5p and 210-3p in breast cancer patients

BACKGROUND

MicroRNAs (miRs), which are stable in the blood, comprise small non-coding RNAs that regulate gene expression. They have important roles in almost all biological pathways, especially in cancer-relevant processes, and have an abnormal expression in breast cancer. In recent studies, the aberrant expression level of various microRNAs has been demonstrated in human cancer. In the present study, the status of serum microRNA-210-3p and microRNA-660-5p expression levels in breast cancer patients was determined compared to healthy controls.

METHODS

Serum samples were collected from 40 newly diagnosed breast cancer patients and 40 healthy controls. A real-time quantitative polymerase chain reaction was utilized to detect the expression levels of these microRNAs. Data analysis was conducted with p < 0.05 being considered statistically significant.

RESULTS

The data obtained showed that serum levels of miR-660-5p and miR-210-3p were significantly up-regulated in breast cancer patients compared to healthy controls (p < 0.001 and p = 0.001, respectively). In addition, significant up-regulation was observed in the early stage (in situ, stage I and II) of breast cancer patients (n = 25) compared to healthy (n = 40) controls (p < 0.001 and p < 0.05, respectively). Receiver-operating characteristic curve analysis indicated that the serum miR-660-5p and miR-210-3p levels have reasonable sensitivity (79% and 68%) and specificity (61% and 51%) for the detection of breast cancer patients (area under the receiver-operating curve = 0.774 and 0.716, respectively).

CONCLUSIONS

Although the results show a reasonable diagnostic accuracy of these microRNAs for detection of breast cancer in this small and preliminary study, further large-scale studies are essential to confirm the presented results.

miRNAs as attractive diagnostic and therapeutic targets for Familial Mediterranean Fever

Familial Mediterranean Fever (FMF) is a hereditary early-onset disease that causes periodical fever attack, excessive release of IL-1β, serositis, arthritis and peritonitis. Genetic analyses conducted on FMF patients (mutated and non-mutated) have highlighted that additional contributing factors such as epigenetics and environment play a role in clinical manifestations of FMF. Recently researchers report that microRNAs (miRNAs), implicated in epigenetic mechanisms, may contribute to the pathogenesis of FMF. miRNAs, a member of the captivating noncoding RNA family, are the single-strand transcripts that work in physiological and pathophysiological processes by regulating target gene expression. Recent studies have shown that miRNAs are associated with various mechanisms involved in the pathogenesis of FMF, such as apoptosis, inflammation and autophagy. Moreover, these miRNAs molecules might have potential use in treatment, therapeutic response monitoring and the diagnosis of subtypes of the disease in the future. Motivated by these potential benefits (diagnostic and therapeutic) of miRNAs, we focus on recent advances of clinical significances and potential action mechanisms of miRNAs in FMF pathogenesis and discuss their potential use for FMF.

Circular RNAs: Promising Biomarkers for Age-related Diseases

Aging is a complex biological process closely linked with the occurrence and development of age-related diseases. Despite recent advances in lifestyle management and drug therapy, the late diagnosis of these diseases causes severe complications, usually resulting in death and consequently impacting social economies. Therefore, the identification of reliable biomarkers and the creation of effective treatment alternatives for age-related diseases are needed. Circular RNAs (circRNAs) are a novel class of RNA molecules that form covalently closed loops capable of regulating gene expression at multiple levels. Several studies have reported the emerging functional roles of circRNAs in various conditions, providing new perspectives regarding cellular physiology and disease pathology. Notably, accumulating evidence demonstrates the involvement of circRNAs in the regulation of age-related pathologies, including cardio-cerebrovascular disease, neurodegenerative disease, cancer, diabetes, rheumatoid arthritis, and osteoporosis. Therefore, the association of circRNAs with these age-related pathologies highlights their potential as diagnostic biomarkers and therapeutic targets for better disease management. Here, we review the biogenesis and function of circRNAs, with a special focus on their regulatory roles in aging-related pathologies, as well as discuss their potential as biological biomarkers and therapeutic targets for these diseases.

Identification and Validation of Potential miRNAs, as Biomarkers for Sepsis and Associated Lung Injury: A Network-Based Approach

Sepsis is a dysregulated immune response disease affecting millions worldwide. Delayed diagnosis, poor prognosis, and disease heterogeneity make its treatment ineffective. miRNAs are imposingly involved in personalized medicine such as therapeutics, due to their high sensitivity and accuracy. Our study aimed to reveal the biomarkers that may be involved in the dysregulated immune response in sepsis and lung injury using a computational approach and in vivo validation studies. A sepsis miRNA Gene Expression Omnibus (GEO) dataset based on the former analysis of blood samples was used to identify differentially expressed miRNAs (DEMs) and associated hub genes. Sepsis-associated genes from the Comparative Toxicogenomics Database (CTD) that overlapped with identified DEM targets were utilized for network construction. In total, 317 genes were found to be regulated by 10 DEMs (three upregulated, namely miR-4634, miR-4638-5p, and miR-4769-5p, and seven downregulated, namely miR-4299, miR-451a, miR181a-2-3p, miR-16-5p, miR-5704, miR-144-3p, and miR-1290). Overall hub genes (HIP1, GJC1, MDM4, IL6R, and ERC1) and for miR-16-5p (SYNRG, TNRC6B, and LAMTOR3) were identified based on centrality measures (degree, betweenness, and closeness). In vivo validation of miRNAs in lung tissue showed significantly downregulated expression of miR-16-5p corroborating with our computational findings, whereas expression of miR-181a-2-3p and miR-451a were found to be upregulated in contrast to the computational approach. In conclusion, the differential expression pattern of miRNAs and hub genes reported in this study may help to unravel many unexplored regulatory pathways, leading to the identification of critical molecular targets for increased prognosis, diagnosis, and drug efficacy in sepsis and associated organ injuries.

Optical Biosensors for the Detection of Rheumatoid Arthritis (RA) Biomarkers: A Comprehensive Review

A comprehensive review of optical biosensors for the detection of biomarkers associated with rheumatoid arthritis (RA) is presented here, including microRNAs (miRNAs), C-reactive protein (CRP), rheumatoid factor (RF), anti-citrullinated protein antibodies (ACPA), interleukin-6 (IL-6) and histidine, which are biomarkers that enable RA detection and/or monitoring. An overview of the different optical biosensors (based on fluorescence, plasmon resonances, interferometry, surface-enhanced Raman spectroscopy (SERS) among other optical techniques) used to detect these biomarkers is given, describing their performance and main characteristics (limit of detection (LOD) and dynamic range), as well as the connection between the respective biomarker and rheumatoid arthritis. It has been observed that the relationship between the corresponding biomarker and rheumatoid arthritis tends to be obviated most of the time when explaining the mechanism of the optical biosensor, which forces the researcher to look for further information about the biomarker. This review work attempts to establish a clear association between optical sensors and rheumatoid arthritis biomarkers as well as to be an easy-to-use tool for the researchers working in this field.

MiR-130a/Ndrg2 Axis Inhibits the Proliferation of Fibroblast-Like Synoviocytes in Rheumatoid Arthritis

Studies have found that N-myc downstream-regulated gene 2 (Ndrg2) is involved in the progression of rheumatoid arthritis (RA); however, the specific mechanism still remains unclear. Gene expression profiles in the tibial joints of the collagen-induced rheumatoid arthritis model were obtained using Gene Expression Omnibus database. Western blot and real-time PCR were respectively performed to determine the expression of Ndrg2 and gene messenger RNA. Cell viability was measured by Cell Counting Kit-8 (CCK-8) method, and cell cycle was detected by flow cytometry. Cell scratch assays were carried out to detect migration. The binding ability of miR-130a to Ndrg2-3'-UTR was predicted by TargetScan website and confirmed by dual luciferase assay. A collagen-induced arthritis rat model was constructed to observe the effects of miR-130a on arthritis index, hind limb swelling, volume of rat hind paw, and inflammation. Ndrg2 was found downregulated in RA tissues, and knockdown of Ndrg2 promoted fibroblast-like synoviocytes (FLS) proliferation and inflammation, while overexpressed Ndrg2 produced opposite results. Ndrg2 was predicted as a target gene for miR-130a, and miR-130a mimic promoted FLS proliferation, while miR-130a inhibitor suppressed FLS proliferation. Moreover, we found that miR-130a antagomir could significantly reduce the arthritis index, swelling degree, foot volume, and inflammatory factor levels; inhibit the expression of miR-130a; and promote the expression of Ndrg2. The miR-130a/Ndrg2 axis signaling pathway is involved in the progression of RA. Our findings provide a theoretical basis for the clinical treatment of RA.

miR-4634 augments the anti-tumor effects of RAD001 and associates well with clinical prognosis of non-small cell lung cancer

MicroRNA (miRNA) is involved in the physiological and pathological processes of various malignancies. In this study, miRNA microarray analysis showed that miR-4634 levels in A549 cells increased significantly after everolimus (RAD001) treatment. Decreased expression of miR-4634 was also found in non-small-cell lung carcinoma (NSCLC) cell lines and patients’ tumors by qPCR. Additionally, a combination of miR-4634 and RAD001 exerted synergistic antitumor efficacy by inhibiting cell proliferation, migration, and colony formation. High expression of miR-4634 was significantly more common in non-cancerous lung tissue than adenocarcinoma or squamous cell carcinoma tissue (72.8%, 45.7%, and 50.9%, respectively; P < 0.001). Furthermore, high expression of miR-4634 was found to be more frequent in patients without lymph node metastasis (P = 0.037) by in-situ hybridization. Importantly, through univariate and multivariate analysis, high miR-4634 expression was associated with better prognosis of NSCLC patients. In conclusion, miR-4634 may act as a tumor suppressor in NSCLC, and to augment the efficacy of RAD001, co-treatment of miR-4634 and RAD001 might be a potential mTOR-targeted cancer therapy strategy for NSCLC patients. High expression of miR-4634 could be an independent good prognostic biomarker for NSCLC.

lncRNA- RP11-156p1.3, novel diagnostic and therapeutic targeting via CRISPR/Cas9 editing in hepatocellular carcinoma

We aim to characterize the expression of RNA panel in HCC. We assessed the expression of HCC-associated mRNA, miRNA and lncRNA network by real time PCR in sera and tissue samples. In a proof-of-principle approach, CRISPR cas9 mediated knock out for lncRNA- RP11-156p1.3 was performed in HEPG2 cell line to validate the role of the chosen RNA in HCC pathogenesis. The differential expression of RFTN1 mRNA, lncRNA- RP11-156p1.3 and miRNA-4764-5p was statistically different among the studied groups. After CRISPR cas9 mediated knockout of lncRNA- RP11-156p1.3 in HEPG2 cells, there was significant decrease in cell count and viability with reversal of the expression of the chosen RNAs. The chosen RNAs play a significant role in HCC pathogenesis and may be potential diagnostic and therapeutic targets.

Different Exosomal microRNA Profile in Aquaporin-4 Antibody Positive Neuromyelitis Optica Spectrum Disorders

Neuromyelitis optica spectrum disorders (NMOSD) and multiple sclerosis (MS) are inflammatory demyelinating diseases of the central nervous system. Exosomal microRNAs (miRNAs) are emerging biomarkers for demyelinating diseases. In this study, 52 aquaporin-4 antibody serum-positive NMOSD patients, 18 relapsing-remitting multiple sclerosis (RRMS) patients and 17 healthy controls (HCs) were included for the next-generation sequencing (NGS). To validate the NGS results, the valuable miRNAs were selected for validation by real-time quantitative polymerase chain reaction in another cohort of patients, comprising 31 NMOSD patients and 14 HCs. In addition, these miRNAs were also validated in a longitudinal study. NGS data revealed the exosomal miRNAs profile in NMOSD patients was different from HCs. Among those potential exosomal miRNAs which can distinguish NMOSD status, hsa-miR-122-3p and hsa-miR-200a-5p were the most abundant miRNAs. In addition, hsa-miR-122-3p and hsa-miR-200a-5p were significantly upregulated in the serum exosome of relapsing NMOSD compared with that in remitting NMOSD. Hsa-miR-122-3p and hsa-miR-200a-5p had positive correlations with disease severity in NMOSD patients. Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that the MAPK, Wnt and Ras signaling pathways were enriched. Further biological function analysis demonstrated that these two miRNAs might be involved in the immunoregulation of NMOSD pathogenesis. Our results indicated that miRNAs delivered by exosomes could be applied as potential biomarkers for NMOSD.

Expression and clinical significance of circular RNAs hsa_circ_0000175 and hsa_circ_0008410 in peripheral blood mononuclear cells from patients with rheumatoid arthritis

Circular RNAs (circRNAs) are a novel class of RNAs that may be used as biomarkers in clinical blood samples. However, the role of circRNAs in rheumatoid arthritis (RA) has not been extensively investigated. In the present study, six circRNAs, including hsa_circ_0082689, hsa_circ_0087798, hsa_circ_0000175, hsa_circ_0008410, hsa_circ_0049356 and hsa_circ_0032959 levels were determined in peripheral blood mononuclear cells (PBMCs) collected from 24 patients with RA and 24 healthy controls (HC) by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) analysis. Hsa_circ_0000175 and hsa_circ_0008410 were selected for further evaluation in an independent cohort consisting of 63 patients with RA, 50 with systemic lupus erythematosus (SLE), 24 with ankylosing spondylitis (AS) and 21 HC. Spearman's rank correlation coefficient was used to analyze the correlation between these two circRNAs and the clinical characteristics of RA, and receiver operating characteristic (ROC) curves were constructed to evaluate their value in RA diagnosis. Multivariate analysis (logistic regression) was used to analyze the risk factors. Of the six selected circRNAs, the expression of hsa_circ_0000175 was found to be significantly reduced and the expression of hsa_circ_0008410 was significantly elevated in PBMCs from patients with RA compared with their levels in HC. The expression of hsa_circ_0000175 in patients with RA was correlated with anti‑citrullinated protein antibodies, white blood cell count, lymphocyte count, lymphocyte percentage, neutrophil count, neutrophil percentage and neutrophil‑to‑lymphocyte ratio. Furthermore, the expression of hsa_circ_0008410 was correlated with tender joint count, disease duration, platelet count and plateletcrit, indicating the activity and severity of RA. ROC curve analysis suggested that hsa_circ_0000175, hsa_circ_0008410, and the combination of hsa_circ_0000175 and hsa_circ_0008410 have significant value in the diagnosis of RA. Hsa_circ_0000175 and hsa_circ_0008410 also differed significantly between patients with RA, and those with SLE and AS. Moreover, logistic regression analysis revealed that the expression of PBMC hsa_circ_0000175 and hsa_circ_0008410 were risk factors for RA. Therefore, PBMC hsa_circ_0000175, hsa_circ_0008410, and the combination of PBMC hsa_circ_0000175 and hsa_circ_0008410 may improve the diagnostic accuracy for RA. In addition, the expression levels of PBMC hsa_circ_0000175 and hsa_circ_0008410 were associated with disease activity and severity of RA.

MicroRNA-9 ameliorates destructive arthritis through down-regulation of NF-κB1-RANKL pathway in fibroblast-like synoviocytes

We investigated the effect of miR-9 on fibroblast-like synoviocytes (FLS) from RA patients and animal arthritis model. The binding of miR-9 to NF-κB1 3'UTR was analyzed by luciferase reporter assay and immunoprecipitation. ChIP assay and luciferase promoter assay were performed to identify the binding of NF-κB1 to RANKL promoter and its activity. FLS were treated with miR-9/anti-miR-9 to evaluate cell proliferation and the expression of RANKL. Therapeutic effect of intra-articular miR-9 was evaluated in type-II collagen-induced arthritis in rats. miR-9 bound to the 3'-UTR of NF-κB1 and downregulated NF-κB1. NF-κB1 bound to RANKL promoter and increased the promoter activity of RANKL. RANKL was downregulated by miR-9. Proliferation of FLS was increased by miR-9 inhibitor. miR-9 dampened experimental arthritis by lowering inflammatory state, reducing RANKL and osteoclasts formation. Our findings revealed miR-9-NF-κB1-RANKL pathway in RA-FLS, further, miR-9 ameliorated inflammatory arthritis in vivo which propose therapeutic implications of miR- 9 in RA.

The Serum Cell-Free microRNA Expression Profile in MCTD, SLE, SSc, and RA Patients

Mixed connective tissue disease (MCTD) is a rare disorder characterized by symptoms that overlap two or more Autoimmune Connective Tissue Diseases (ACTDs). The aim of this study was to determine whether miRNAs participating in the TLRs signaling pathway could serve as biomarkers differentiating MCTD or other ACTD entities from a healthy control group and between groups of patients. Although the selected miRNA expression level was not significantly different between MCTD and control, we observed that miR-126 distinguishes MCTD patients from all other ACTD groups. The expression level of miRNAs was significantly higher in the serum of systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) patients compared to controls. The miR-145 and -181a levels distinguished RA from other ACDT patients. miR-155 was specific for SLE patients. MiR-132, miR-143, and miR-29a distinguished RA and SLE patients from the systemic sclerosis (SSc) group. Additionally, some clinical parameters were significantly related to the miRNA expression profile in the SLE group. SLE and RA are characterized by a specific serum expression profile of the microRNAs associated with the Toll-like receptors (TLRs) signaling pathway. The analysis showed that their level distinguishes these groups from the control and from other ACTD patients. The present study did not reveal a good biomarker for MCTD patients.

Dysregulation of Inflammasome Priming and Activation by MicroRNAs in Human Immune-Mediated Diseases

Inflammasomes are protein complexes that respond to a wide range of pathogens and cellular damage signals. Their activation prompts the caspase-1-mediated cleavage of the proinflammatory cytokines IL-1β and IL-18. Inflammasome dysregulation has been demonstrated to play a role in a range of diseases involving the adaptive immune system like multiple sclerosis, rheumatic diseases, and type 1 diabetes. Priming and activation of inflammasomes can be modulated by microRNAs (miRNAs), small noncoding RNAs that regulate gene expression posttranscriptionally. miRNAs, such as miR-223-3p, have been demonstrated to directly target the inflammasome components NLRP3, caspase-1, and caspase-8. Other miRNAs like miR-155-5p modulate TLR-, IL-1R-, TNFR-, and IFNAR-mediated signaling pathways upstream of the inflammasomes. In this study, we discuss how a more detailed elucidation of miRNA-driven inflammasome regulation helps in understanding the molecular processes underlying immune-mediated human diseases, holds potential for the identification of biomarkers and may offer novel targets for the development of future therapeutics.

Identification of PBMC-expressed miRNAs for rheumatoid arthritis

Post-transcriptional regulation by miRNAs plays an important role in the pathogenesis of rheumatoid arthritis (RA), however, the roles of specific miRNAs in RA pathogenesis remain largely unclear. This study performed dual-omics (miRNA and mRNA) integration analysis and in-depth cellular and molecular functional exploration to identify novel RA-associated miRNAs and to understand their underlying pathogenic mechanism. Based on the miRNA and mRNA expression profiles in peripheral blood mononuclear cells (PBMCs) from a discovery sample set (25 RA cases and 18 healthy controls), 18 differentially expressed miRNAs (DEMIRs) (|Fold-change|>2 and P < 0.05) were identified and corresponding interaction networks of DEMIRs and mRNA were constructed. After the expression validation of the DEMIRs in a validation sample set (35 RA cases and 35 healthy controls), miR-99b-5p was highlighted. The over-expression of newly discovered miR-99b-5p is able to suppress T cell apoptosis, promote cell proliferation and activation, increase expression of proinflammatory cytokines (IL-2, IL-6, TNF-α, and IFN-γ), and inhibit expression of its target genes mTOR and RASSF4. This study comprehensively identified PBMC-expressed miRNAs along with corresponding regulatory networks significant for RA and discovered miR-99b-5p as a novel post-transcriptional mediator involved in RA pathogenesis. The findings improved our understanding of RA pathogenesis and provided novel insights into the molecular mechanisms underlying RA pathogenesis.

MicroRNAs in rheumatoid arthritis: From pathogenesis to clinical impact

Over the last decade, many epigenetic mechanisms that contribute in the pathogenesis of autoimmune disorders have been revealed. MicroRNAs (miRNAs) are small, non-coding, RNA molecules that bind to messenger RNAs and disrupt the transcription of target genes. Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease in which a plethora of epigenetic changes take place. Current research on RA epigenetics has focused mainly on miRNAs. Genetic variance of some miRNA genes, especially miR-499, might predispose an individual to RA development. Additionally, altered expression of many miRNAs has been discovered in several cells, tissues and body fluids in patients with RA. MiRNAs expression also differs depending on disease's stage and activity. Serum miR-22 and miR-103a might predict RA development in susceptible individuals (pre-RA), while serum miR-16, miR-24, miR-125a and miR-223 levels are altered in early RA (disease duration <12 months) patients compared to established RA or healthy individuals. Moreover, serum miR-223 levels have been associated with RA activity and disease relapse. What is more, serum levels of several miRNAs, including miR-125b and miR-223, could be used to predict response to RA treatment. Finally, miRNA analogs or antagonists have been used as therapeutic regimens in experimental arthritis models and have demonstrated promising results. In conclusion, the research on the miRNA alterations in RA sheds light to several aspects of RA pathogenesis, introduces new biomarkers for RA diagnosis and treatment response prediction and offers the opportunity to discover new, targeted drugs for patients with RA.

MiR-5571-3p and miR-135b-5p, derived from analyses of microRNA profile sequencing, correlate with increased disease risk and activity of rheumatoid arthritis

OBJECTIVES

This study aimed to investigate microRNA (miRNA) expression profiles in synovium tissues of rheumatoid arthritis (RA) patients by RNA sequencing and to evaluate the values of dysregulated miRNAs in RA diagnosis and monitoring.

METHODS

Thirty RA patients who underwent knee arthroscopy and 30 controls with knee trauma who underwent surgery were consecutively recruited, and synovium tissue samples of both groups were obtained during surgeries. In the exploration part, miRNA and mRNA expression profiles of 3 RA samples and 3 control samples were detected using RNA sequencing then followed by bioinformatic analyses. In the validation part, 5 candidate miRNA levels were detected by quantitative polymerase chain reaction (qPCR) in 30 RA patients and 30 control patients.

RESULTS

In the exploration part, 78 miRNAs and 1582 mRNAs were upregulated while 40 miRNAs and 1295 mRNAs were downregulated in synovium tissue samples of RA patients compared with those of controls. Furthermore, enrichment analyses revealed that these dysregulated miRNAs and mRNAs were mainly implicated in immune activities and inflammatory diseases such as leukocyte migration, complement activation, and RA. In the validation part, qPCR assay revealed that miR-5571-3p and miR-135b-5p expressions were increased in RA patients compared with those in controls and disclosed good predictive values for RA risk with high area under the curves (AUCs). Besides, both miR-5571-3p and miR-135b-5p levels were positively correlated with disease activity and inflammation level of RA.

CONCLUSIONS

Analyses of miRNA expression profiles by sequencing indicate that miR-5571-3p and miR-135b-5p correlate with increased RA risk and activity.

Circular RNAs in immune responses and immune diseases

Circular RNAs (circRNAs) are novel clusters of endogenous noncoding RNAs (ncRNAs) that are widely expressed in eukaryotic cells. In contrast to the generation of linear RNA transcripts, circRNAs undergo a "back-splicing" process to form a continuous, covalently closed, stable loop structure without 5' or 3' polarities and poly (A) tails during posttranscriptional modification. Due to the widespread availability of several technologies, especially high-throughput RNA sequencing, numerous circRNAs have been discovered not only in mammals but also in plants and insects. Notably, due to their abilities to serve as microRNA (miRNA) "sponges", miRNA "reservoirs", regulate gene expression and encode proteins, circRNAs participate in the development and progression of different immune responses and immune diseases by enriching various forms of epigenetic modification. CircRNAs have been demonstrated to be expressed in a tissue-specific and pathogenesis-related manner during the occurrence of multiple immune diseases. Additionally, because of their circular configurations, expression in blood and peripheral tissues and coexistence with exosomes, circRNAs show inherent conservation along with environmental resistance stability and may be regarded as potential biomarkers or therapeutic targets for some immune diseases. In this review, we summarize the characteristics, functions and mechanisms of circRNAs and their involvement in immune responses and diseases. Although our knowledge of circRNAs remains preliminary, this field is worthy of deeper exploration and greater research efforts.

Role of miR-9-5p in preventing peripheral neuropathy in patients with rheumatoid arthritis by targeting REST/miR-132 pathway

MicroRNAs (miRNAs) are found to play a key role in neural cell differentiation, peripheral nerve injury, and rheumatoid arthritis (RA). However, no study has yet been conducted highlighting their role in RA-induced peripheral neuropathy. Here, we investigated the role of miRNAs in RA-induced peripheral neuropathy. Levels of six miRNAs were detected in serum collected from 15 patients with RA and peripheral neuropathy and 16 patients with RA. In vitro, Schwann cells were treated with 0.1 ng/mL IL-6 and 20 ng/mL TNF-α. The expression level of miR-9-5p and its association with the repressor element-1 silencing transcription factor (REST) were investigated. The roles of miR-9-5p and REST in Schwann cell injury were examined after transfection of miR-9-5p mimics or REST siRNA. In patients with RA and peripheral neuropathy, serum miR-9-5p was significantly downregulated when compared with RA. In IL-6- and TNF-α-stimulated Schwann cells, apoptosis was induced, while the cell viability and level of miR-9-5p were inhibited. A significantly negative correlation was observed between miR-9-5p and REST. Transfection of miR-9-5p mimics and REST siRNA significantly reversed the inhibition of cell viability and induction of apoptosis caused by IL-6 and TNF-α. In addition, overexpression of miR-9-5p upregulated the expression of miR-132, miRNA targeting E1A binding protein EP300 (EEP300), phosphatase and tensin homolog (PTEN) and forkhead box O3 (FOXO3). These results showed that Schwann cells were protected by miR-9-5p from inflammatory damage by targeting REST/miR-132 pathway, which could provide new targets for treatment of RA-induced peripheral neuropathy.

MiR-3926 inhibits synovial fibroblasts proliferation and inflammatory cytokines secretion through targeting toll like receptor 5

Rheumatoid arthritis synovial fibroblasts (RASFs) play a key role in the pathogenesis of rheumatoid arthritis (RA). This study was aimed to investigate the effects of miR-3926 on the biological activities of RASFs. The results showed that miR-3926 was significantly down-regulated in RASFs and RA synovial tissue. Overexpression of miR-3926 significantly inhibited RASFs proliferation and decreased the secretion of inflammatory cytokines including TNF-α, IL-1β and IL-6 in RASFs. TLR5 was identified to be a direct target of miR-3926. TLR5 showed an opposite expression trends with miR-3926 in RASFs and RA synovial tissue. Overexpression of miR-3926 led to a reduction of endogenous TLR5 in RASFs, whereas down-regulation of miR-3926 increased TLR5 expression. Knocking down of TLR5 significantly inhibited RASFs proliferation and inflammatory cytokines secretion. Rescue experiments with a miR-3926-resistant variant of TLR5 showed that overexpression of TLR5 restored RASFs proliferation and inflammatory cytokines secretion in miR-3926-overexpressing RASFs. In conclusion, miR-3926 is downregulated in RA synovial tissues and its overexpression caused the inhibitory effects on RASF proliferation and inflammatory cytokines secretion by targeting TLR5. The miR-3926/TLR5 pathway may represent a novel target for prevention and treatment of RA.

Differential MicroRibonucleic Acid Expression in Cardioembolic Stroke

BACKGROUND

MicroRNAs (miRNA) are a class of small, endogenous (17-25 nucleotide) noncoding ribonucleic acids implicated in the transcriptional and post-transcriptional regulation of gene expression. This study examines stroke-specific miRNA expression in large vessel territory cardioembolic stroke.

METHODS

Peripheral blood was collected from controls and ischemic stroke patients 24 hours after stroke onset. Whole blood miRNA was isolated and analyzed for differential expression. A total of 16 patients with acute middle cerebral artery territory strokes of cardioembolic origin were included in this pilot study. MiRNA profiling was conducted by miRCURY LNA™ microRNA Array.

RESULTS

In patients with cardioembolic stroke, significant differential expression of 14 miRNAs was observed when compared to controls. Ten of these miRNA had not previously been associated with ischemic stroke (miR-664a-3p, -2116-5pp, -4531, -4765-5p, -647, -4709-3p, -4742-3p, -5584-3p, -4756-3p, and -5187-3p). Subanalysis of severe strokes (NIHSS > 10) identified an additional 5 differentially expressed miRNA. No significant effects of sex or tissue plasminogen activator treatment were seen on miRNA expression.

CONCLUSIONS

Ischemic stroke patients show a differential miRNA expression profile as compared to controls. These new associations between circulating miRNAs and ischemic stroke may help to refine stroke subtype diagnosis and identify novel therapeutic miRNA targets for the treatment of ischemic stroke.

Identification of circular RNAs hsa_circ_0044235 in peripheral blood as novel biomarkers for rheumatoid arthritis

Circular RNAs (circRNAs) are a new class of RNAs that can be used as biomarkers in clinical blood samples. However, little is known about circRNAs' diagnostic values for rheumatoid arthritis (RA). In this study, the hsa_circ_0054189, hsa_circ_0008675, hsa_circ_0082689, hsa_circ_0082688, hsa_circ_0010932, hsa_circ_0002473 and hsa_circ_0044235 in peripheral blood were determined by quantitative reverse transcription–polymerase chain reaction (qRT–PCR). For hsa_circ_0044235, only one abnormal expression circRNAs in peripheral blood was selected as a targeted circRNA to explore the diagnostic value for RA. Our work demonstrated that the hsa_circ_0044235 in peripheral blood was decreased significantly in RA patients. The hsa_circ_0044235 in peripheral blood from RA patients did not correlate with C‐reactive protein (CRP), erythrocyte sedimentation rate (ESR), rheumatoid factor (RF), anti‐citrullinated protein antibodies (ACPA) or disease activity score 28 (DAS28). Receiver operating characteristic (ROC) curve analysis suggested that the hsa_circ_0044235 in peripheral blood has significant value in the diagnosis of RA. The risk score based on hsa_circ_0044235 in peripheral blood also distinguished significantly the patients with RA from systemic lupus erythematosus (SLE). This study suggests that the hsa_circ_0044235 in peripheral blood may be a potential biomarker of patients with RA.

Overexpression of serum MicroRNA-140-3p in premenopausal women with newly diagnosed breast cancer

AIMS

The purpose of the present study was to evaluate microRNA-140-3p expression level in breast cancer patients in comparison to healthy controls.

PATIENTS & METHODS

Serum microRNA-140-3p level was quantified by realtime quantitative reverse transcription PCR in 40 women with breast cancer and 40 healthy subjects.

RESULTS

Serum microRNA-140-3p level in patients compared to healthy subjects was significantly up-regulated (P = 0.01). MicroRNA-140-3p had a good diagnostic accuracy for discrimination of the two groups (AUC = 0.667; sensitivity = 70%; specificity = 50%). Serum microRNA-140-3p level was overexpressed in premenopausal patients who were ≤48 years old. ROC curve showed a similar pattern again (AUC = 0.690; sensitivity = 73%; specificity = 50%).

CONCLUSIONS

microRNA-140-3p has the potential for detection of breast cancer, especially in premenopausal and in ≤48 years old women.

MicroRNA-122-3p inhibits tumor cell proliferation and induces apoptosis by targeting Forkhead box O in A549 cells

The imbalance between cell proliferation and apoptosis was implicated to serve key roles in cancer pathogenesis. The characteristics of microRNAs (miRNAs/miRs) have attracted much attention in research focusing on cancer pathogenesis in recent years. miR-122-3p has been reported to be associated with a number of disease processes and pathogenesis, including lung cancer. The present study aimed to investigate the association of miR-122-3p expression level with cell proliferation and apoptosis in a lung cancer cell line. A549 cells were transfected with miR-122-3p to interrupt the expression of miR-122-3p. Subsequently, MTT and BrdU assay, and western blot were used to analyze the influence of miR-122-3p on lung cancer cell proliferation, cell viability and its underlying mechanism. The present study revealed that, by targeting p27, overexpression of miR-122-3p inhibited cell proliferation in lung cancer. Furthermore, the cell apoptosis analysis suggested that overexpression of miR-122-3p was able to inhibit cell apoptosis by targeting Forkhead box O. These findings suggest that miR-122-3p may be associated with the pathology and progression of lung cancer and be a new therapeutic target for this disease.

Circular RNA expression profiles of peripheral blood mononuclear cells in rheumatoid arthritis patients, based on microarray chip technology

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by chronic synovial inflammation and finally leads to variable degrees of bone and cartilage erosion. The diagnosis of RA is not an accurate indicator, but a series of scores and the mechanisms underlying it remain only partially understood. The present study explored whether circular RNAs (circRNAs) contribute to the RA pathophysiological mechanism. Total RNA from peripheral blood mononuclear cells of 10 RA patients and 10 healthy controls were extracted and circRNA expression profiling was followed by microarray analysis. In addition, circRNA interactions with microRNAs were performed and microRNA response elements were listed to identify differentially expressed binding site targets in RA. Reverse transcription-quantitative polymerase chain reaction amplification (RT-qPCR) was used to verify the differential expression of circRNAs. A total of 584 circRNAs were differentially expressed in RA patients vs. healthy controls, by circRNA microarray, including 255 circRNAs which were significantly upregulated and 329 downregulated among the RA samples. RT-qPCR validation demonstrated that the expression levels of hsa_circRNA_104194, hsa_circRNA_104593, hsa_circRNA_103334, hsa_circRNA_101407 and hsa_circRNA_102594 were consistent with the results from the microarray analysis. The current study presented differentially expressed circRNAs and their corresponding microRNA binding sites in RA. circRNAs may exhibit a role in the regulation of expression of symbol genes that influence the occurrence and development of RA.

MicroRNAs as Peripheral Biomarkers in Aging and Age-Related Diseases

MicroRNAs (miRNAs) are found in the circulatory biofluids considering the important molecules for biomarker study in aging and age-related diseases. Blood or blood components (serum/plasma) are primary sources of circulatory miRNAs and can release these in cell-free form either bound with some protein components or encapsulated with microvesicle particles, called exosomes. miRNAs are quite stable in the peripheral circulation and can be detected by high-throughput techniques like qRT-PCR, microarray, and sequencing. Intracellular miRNAs could modulate mRNA activity through target-specific binding and play a crucial role in intercellular communications. At a pathological level, changes in cellular homeostasis lead to the modulation of molecular function of cells; as a result, miRNA expression is deregulated. Deregulated miRNAs came out from cells and frequently circulate in extracellular body fluids as part of various human diseases. Most common aging-associated diseases are cardiovascular disease, cancer, arthritis, dementia, cataract, osteoporosis, diabetes, hypertension, and neurodegenerative diseases such as Alzheimer's disease, Huntington's disease, Parkinson's disease, and amyotrophic lateral sclerosis. Variation in the miRNA signature in a diseased peripheral circulatory system opens up a new avenue in the field of biomarker discovery. Here, we measure the biomarker potential of circulatory miRNAs in aging and various aging-related pathologies. However, further more confirmatory researches are needed to elaborate these findings at the translation level.

MicroRNA-613 regulates the expression of brain-derived neurotrophic factor in Alzheimer's disease

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive loss of memory and other cognitive functions and presents an increasing clinical challenge in terms of diagnosis and treatment. Brain-derived neurotrophic factor (BDNF) plays an important role in neuronal survival and proliferation. In the present study, the mRNA and protein expression level of BDNF was detected in serum, and cerebrospinal fluid (CSF) of patients with mild cognitive impairment (MCI), dementia of Alzheimer's type (DAT), and hippocampus in APP/PS1 mice. A significant decrease of BDNF mRNA and protein expression was observed in serum and CSF of patients and hippocampus in APP/PS1 mice compared with the corresponding controls. miR-613, which is predicted to target the 3'-UTR of BDNF, was also detected in patients and the mouse model. Opposite to the alteration of BDNF, miR-613 expression in serum, CSF and hippocampus were obviously increased compared to the controls. In conclusion, these findings showed that miR-613 may function in the development of AD and may provide new insights in diagnosis and treatment of AD.