Down-Regulation of lncRNA-AK001085 and its Influences on the Diagnosis of Ankylosing Spondylitis

Jianpi Qingre Tongluo Decoction exerted an anti-inflammatory effect on AS by inhibiting the NONHSAT227927.1/JAK2/STAT3 axis

Purpose

This study aims to determine whether Jianpi Qingre Tongluo Decoction (JQP) alleviates ankylosing spondylitis (AS) inflammation via the NONHSAT227927.1/JAK2/STAT3 axis.

Methods

The effect of JQP on immune-inflammatory indicators in AS patients was explored through a combination of data mining, association rule analysis, and random walk model evaluation. Subsequently, network pharmacology and molecular docking were performed to screen out the potential signaling pathway. ELISA, PCR and wb were used to evaluate the effect of JQP on AS-FLS activity and inflammatory factors. The role of NONHSAT227927.1/JAK2/STAT3 combination in inflammation was studied by editing NONHSAT227927.1 and adding the JAK2/STAT3 inhibitor AG490. Involvement of the JAK2/STAT3 pathway was detected by PCR, WB, or immunofluorescence analysis.

Results

Retrospective data mining results show that JQP can effectively reduce the immune inflammatory response in AS patients. Through network pharmacology and molecular docking, it is speculated that JQP exerts its effect on AS through the JAK2/STAT3 pathway. Overexpression of NONHSAT227927.1 activated the JAK2/STAT3 pathway and promoted the expression of inflammatory factors, while serum containing JQP reversed the effects of NONHSAT227927.1 overexpression. NONHSAT227927.1 silencing inhibits the proliferation of AS-FLSs, inhibits the levels of inflammatory factors, and reduces the expression of JAK2/STAT3 protein. After adding the pathway blocker AG490, it was observed that the cell viability of AS-FLSs was reduced by inflammatory factors and the levels of JAK2/STAT3 were inhibited. , and overexpression of NONHSAT227927.1 can reverse this trend.

Conclusions

JQP exerted an anti-inflammatory effect on AS by inhibiting the NONHSAT227927.1/JAK2/STAT3 axis.

LncRNA SNHG1 serves as a biomarker for systemic lupus erythematosus and participates in the disease progression

LncRNAs play an important role in autoimmune diseases. The purpose of this study was to explore the role of lncRNA SNHG1 in systemic lupus erythematosus (SLE), and laid a theoretical foundation for the study of SLE. The basic clinical information of all subjects was first collected for statistical analysis, and SNHG1 expression in the serum of all subjects was detected by RT-qPCR. The value of SNHG1 in the diagnosis of SLE was assessed by ROC. The correlation between SNHG1 and each blood sample index was analyzed by Pearson correlation analysis. The role of SNHG1 in primary peripheral blood mononuclear cells (PBMCs) apoptosis was explored. SNHG1 expression is relatively upregulated in patients with SLE compared to healthy people. SNHG1 expression was positively correlated with SLEDAI score, IgG, CRP, and ESR, and negatively correlated with C3 and C4. ROC indicated that SNHG1 has the potential to assist in the diagnosis of SLE. PBMCs apoptosis in SLE was higher than that in control group, the knockdown and overexpression of SNHG1 could correspondingly inhibit and promote PBMCs apoptosis. SNHG1 has the potential to be a diagnosis marker for SLE and may be involved in regulating PBMCs apoptosis.

A review of long non-coding RNAs in ankylosing spondylitis: pathogenesis, clinical assessment, and therapeutic targets

Ankylosing spondylitis (AS) is a chronic immune-mediated type of inflammatory arthritis characterized by inflammation, bone erosion, and stiffness of the spine and sacroiliac joints. Despite great efforts put into the investigation of the disease, the pathogenesis of AS remains unclear, posing challenges in identifying ideal targets for diagnosis and treatment. To enhance our understanding of AS, an increasing number of studies have been conducted. Some of these studies reveal that long non-coding RNAs (lncRNAs) play crucial roles in the etiology of AS. Some certain lncRNAs influence the development of AS by regulating inflammatory responses, autophagy, apoptosis, and adipogenesis, as well as the proliferation and differentiation of cells. Additionally, some lncRNAs demonstrate potential as biomarkers, aiding in monitoring disease progression and predicting prognosis. In this review, we summarize recent studies concerning lncRNAs in AS to elucidate the underlying mechanisms in which lncRNAs are involved and their potential values as biomarkers for disease assessment and druggable targets for therapy.

Triptolide alleviates the development of inflammation in ankylosing spondylitis via the NONHSAT227927.1/JAK2/STAT3 pathway

Ankylosing spondylitis (AS) is a chronic inflammatory disease that can destroy the affected joints. Triptolide (TPL), a key active ingredient of the traditional Chinese medicine Tripterygium wilfordii exhibits promising efficacy in rheumatic immune disease with its anti-inflammatory effects. The present study aimed to elucidate the mechanism of TPL in treatment of AS by regulating the long non-coding RNA (lncRNA) NONHSAT227927.1. The role and underlying mechanisms of TPL in the development of inflammation in AS were assessed. In vivo, the expression of NONHSAT227927.1 in AS was detected by reverse transcription-quantitative (RT-q)PCR. Correlation analysis and binary logistic regression were performed between immune and inflammatory indicators, perception scale scores of patients and NONHSAT227927.1. In vitro, Cell Counting Kit-8 was used to evaluate the activity of AS-fibroblast-like synoviocytes (FLSs) following TPL exposure. AS-FLS inflammation was assessed by qPCR and ELISA. The interaction between TPL and JAK2 and STAT3 was verified by molecular docking and the JAK2/STAT3 pathway components were detected by western blotting. NONHSAT227927.1 was knocked down by small interfering RNA to determine its role. NONHSAT227927.1 was highly expressed in vivo and positively correlated with disease duration, disease duration, Body mass index (BMI), C-reactive protein (CRP), Visual analog scale (VAS), Visual analog scale (VAS), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and Bath Ankylosing Spondylitis Metrology Index, among which ESR and VAS and BASDAI score were risk factors for NONHSAT227927.1. TPL downregulated pro-inflammatory factors in AS-FLSs and inhibited the JAK2/STAT3 pathway via NONHSAT227927.1. TPL inhibited inflammatory factors in AS-FLSs and alleviated inflammatory responses via the NONHSAT227927.1/JAK2/STAT3 axis.

Emerging Roles of Long Non-Coding RNAs in Ankylosing Spondylitis

Ankylosing spondylitis (AS) is a chronic systemic autoimmune disease characterized by inflammation, bone erosion, spur formation of the spine and the sacroiliac joints. However, the etiology and molecular pathogenesis of AS remain largely unclear. Recently, a growing number of studies showed that long non-coding RNAs (lncRNAs) played critical roles in the development and progression of autoimmune and orthopedic conditions, including AS. Studies demonstrated that a myriad of lncRNAs (e.g. H19, MEG3, LOC645166) pertinent to regulation of inflammatory signals were deregulated in AS. A number of lncRNAs might also serve as new biomarkers for the diagnosis and predicting the outcomes of AS. In this review, we summarize lncRNA profiling studies on AS and the functional roles and mechanism of key lncRNAs relevant to AS pathogenesis. We also discuss their potential values as biomarkers and druggable targets for this potentially disabling condition.

Comprehensive lncRNA and mRNA profiles in peripheral blood mononuclear cells derived from ankylosing spondylitis patients by RNA-sequencing analysis

The present study aimed to investigate the comprehensive expression profiles of long non-coding RNA (lncRNA) in ankylosing spondylitis (AS).The peripheral blood samples were collected from 6 AS patients and 6 age- and gender-matched healthy controls (HCs), and separated for peripheral blood mononuclear cells, followed by RNA-sequencing. Further bioinformatics analyses were performed to explore the significantly enriched biological processes, signaling pathways of differentially expressed lncRNAs (DElncRNAs) (based on cis-target and trans-target genes) and differentially expressed mRNAs (DEmRNAs).Principal component analysis plots indicated that both lncRNA and mRNA expression profiles could distinguish AS patients from HCs; heatmap diagram exhibited a relatively good consistency and tendency of lncRNA and mRNA expression profiles in AS patients and HCs, respectively; volcano plots exhibited 114 upregulated and 45 downregulated DElncRNAs, 284 upregulated and 435 downregulated DEmRNAs in AS patients compared with HCs; Gene ontology enrichment analyses indicated that DElncRNAs (based on cis-target and trans-target genes) and DEmRNAs were enriched in molecular functions (including DNA binding, protein binding, etc) and biological process (including immune response, inflammatory response, etc); Kyoto Encyclopedia of Genes and Genomes enrichment analyses revealed that these DElncRNAs (based on cis-target and trans-target genes) and DEmRNAs were enriched in immune and inflammation-related signaling, such as B cell receptor signaling pathway, TNF signaling pathway, NF-kappa B signaling pathway, etc.Our study displays the comprehensive expression profiles and functions of lncRNAs involved in AS, which provides reference for further researches discovering candidate lncRNAs with value in assisting early AS diagnosis.

Integrative analysis of long non-coding RNA and messenger RNA expression in toll-like receptor 4-primed mesenchymal stem cells of ankylosing spondylitis

Background

The precise pathogenesis of ankylosing spondylitis (AS) is still largely unknown at present. Our previous study found that toll-like receptor 4 (TLR4) downregulated and performed immunoregulatory dysfunction in mesenchymal stem cells from AS patients (AS-MSCs). The aim of this study was to explore the expression profiles of long non-coding RNAs (lncRNAs) and messenger RNAs (mRNAs) in TLR4-primed AS-MSCs, and to clarify the potential mechanisms.

Methods

The immunoregulatory effects of MSCs were determined after TLR4 activation. Next, the differentially-expressed (DE) lncRNAs and mRNAs between AS-MSCs and TLR4-primed AS-MSCs [stimulated by lipopolysaccharide (LPS)] were identified via high-throughput sequencing followed by quantitative real-time PCR (qRT-PCR) confirmation. Finally, bioinformatics analyses were performed to identify the critical biological functions, signaling pathways, and associated functional networks involved in the TLR4-primed immunoregulatory function of AS-MSCs.

Results

A total of 147 DE lncRNAs and 698 DE mRNAs were identified between TLR4-primed AS-MSCs and unstimulated AS-MSCs. Of these, 107 lncRNAs were upregulated and 40 were downregulated (fold change ≥2, P<0.05), while 504 mRNAs were upregulated and 194 were downregulated (fold change ≥2, P<0.05). Five lncRNAs and five mRNAs with the largest fold changes were respectively verified by qRT-PCR. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses demonstrated that the DE mRNAs and lncRNAs were highly associated with the inflammatory response, such as NOD-like receptor (NLR) signaling pathway, the TNF signaling pathway and the NF-κB signaling pathway. Cis-regulation prediction revealed eight novel lncRNAs, while trans-regulation prediction revealed 15 lncRNAs, respectively. Eight core pairs of lncRNA and target mRNA in the lncRNA-transcription factor (TF)-mRNA network were as follows: PACERR-PTGS2, LOC105378085-SOD2, LOC107986655-HIVEP2, MICB-DT-MICB, LOC105373925-SP140L, LOC107984251-IFIT5, LOC112268267-GBP2, and LOC101926887-IFIT3, respectively.

Conclusions

TLR4 activation in AS can enhance the immunoregulatory ability of MSCs. Eight core pairs of lncRNA and target mRNA were observed in TLR4-primed AS-MSCs, which could contribute to understanding the potential mechanism of AS-MSC immunoregulatory dysfunction.

LncRNAs as a new regulator of chronic musculoskeletal disorder

Objectives

In recent years, long non‐coding RNAs (lncRNAs) have been found to play a role in the occurrence, progression and prognosis of chronic musculoskeletal disorders.

Design and methods

Literature exploring on PubMed was conducted using the combination of keywords 'LncRNA' and each of the following: 'osteoarthritis', 'rheumatoid arthritis', 'osteoporosis', 'osteogenesis', 'osteoclastogenesis', 'gout arthritis', 'Kashin‐Beck disease', 'ankylosing spondylitis', 'cervical spondylotic myelopathy', 'intervertebral disc degeneration', 'human muscle disease' and 'muscle hypertrophy and atrophy'. For each disorder, we focused on the publications in the last five years (5/1/2016‐2021/5/1, except for Kashin‐Beck disease). Finally, we excluded publications that had been reported in reviews of various musculoskeletal disorders during the last three years. Here, we summarized the progress of research on the role of lncRNA in multiple pathological processes during musculoskeletal disorders.

Results

LncRNAs play a crucial role in regulating downstream gene expression and maintaining function and homeostasis of cells, especially in chondrocytes, synovial cells, osteoblasts, osteoclasts and skeletal muscle cells.

Conclusions

Understanding the mechanisms of lncRNAs in musculoskeletal disorders may provide promising strategies for clinical practice.

Identification of lncRNAs associated with the pathogenesis of ankylosing spondylitis

Background

Ankylosing spondylitis (AS) is a chronic autoimmune disease affecting the sacroiliac joint. To date, few studies have examined the association between long non-coding RNAs (lncRNAs) and AS pathogenesis. As such, we herein sought to characterize patterns of AS-related lncRNA expression and to evaluate the potential role played by these lncRNAs in this complex autoimmune context.

Methods

We conducted a RNA-seq analysis of peripheral blood mononuclear cell (PBMC) samples isolated from five AS patients and corresponding controls. These data were then leveraged to characterize AS-related lncRNA expression patterns. We further conducted GO and KEGG enrichment analyses of the parental genes encoding these lncRNAs, and we confirmed the validity of our RNA-seq data by assessing the expression of six lncRNAs via qRT-PCR in 15 AS and control patient samples. Pearson correlation analyses were additionally employed to examine the associations between the expression levels of these six lncRNAs and patient clinical index values.

Results

We detected 56,575 total lncRNAs in AS and control patient samples during our initial RNA-seq analysis, of which 200 and 70 were found to be up- and down-regulated (FC > 2 or < 0.05; P < 0.05), respectively, in AS samples relative to controls. In qRT-PCR validation assays, we confirmed the significant upregulation of NONHSAT118801.2, ENST00000444046, and NONHSAT183847.1 and the significant downregulation of NONHSAT205110.1, NONHSAT105444.2, and NONHSAT051856.2 in AS patient samples. We further found the expression of NONHSAT118801.2 and NONHSAT183847.1 to be positively correlated with disease severity.

Conclusion

Overall, our findings highlight several lncRNAs that are specifically expressed in PBMCs of AS patients, indicating that they may play key functions in the pathogenesis of this autoimmune disease. Specifically, we determined that NONHSAT118801.2 and NONHSAT183847.1 may influence the occurrence and development of AS.

Epigenomic and transcriptomic analysis of chronic inflammatory diseases

Chronic inflammatory diseases (CIDs) have complex pathologies that result from aberrant and persistent immune responses. However, the precise triggers and mechanisms remain elusive. An important aspect of CID research focuses on epigenetics modifications, which regulate gene expression and provide a dynamic transcriptional response to inflammation. In recent years, mounting evidence has demonstrated an association between epigenomic and transcriptomic dysregulation and the phenotypes of CIDs. In particular, epigenetic changes at cis-regulatory elements have provided new insights for immune cell-specific alterations that contribute to disease etiology. Furthermore, the advancements in single-cell genomics provide novel solutions to cell type heterogeneity, which has long posed challenges for CID diagnosis and treatment. In this review, we discuss the current state of epigenomics research of CID and the insights derived from single-cell transcriptomic and epigenomic studies.

Comprehensive Analysis of Differentially Expressed lncRNA, circRNA and mRNA and Their ceRNA Networks in Mice With Severe Acute Pancreatitis

Severe acute pancreatitis (SAP) is an acute digestive system disease with high morbidity mortality and hospitalization rate worldwide, due to various causes and unknown pathogenesis. In recent years, a large number of studies have confirmed that non-coding RNAs (ncRNAs) play an important role in many cellular processes and disease occurrence. However, the underlying mechanisms based on the function of ncRNAs, including long noncoding RNA (lncRNA) and circular RNA (circRNA), in SAP remain unclear. In this study, we performed high-throughput sequencing on the pancreatic tissues of three normal mice and three SAP mice for the first time to describe and analyze the expression profiles of ncRNAs, including lncRNA and circRNA. Our results identified that 49 lncRNAs, 56 circRNAs and 1,194 mRNAs were differentially expressed in the SAP group, compared with the control group. Furthermore, we performed Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of differentially expressed lncRNAs and circRNAs, and found that the functions of the parental genes are enriched in the calcium-regulated signaling pathway, NF-κB signaling pathway, autophagy and protein digestion and absorption processes, which are closely related to the central events in pathogenesis of SAP. We also constructed lncRNA/circRNA-miRNA-mRNA networks to further explore their underlying mechanism and possible relationships in SAP. We found that in the competitive endogenous RNA (ceRNA) networks, differentially expressed lncRNAs and circRNAs are mainly involved in the apoptosis pathway and calcium signal transduction pathway. In conclusion, we found that lncRNAs and circRNAs play an important role in the pathogenesis of SAP, which may provide new insights in further exploring the pathogenesis of SAP and seek new targets for SAP.

Profiling and Bioinformatics Analysis of Differentially Expressed circRNAs in Spinal Ligament Tissues of Patients with Ankylosing Spondylitis

Recent studies have reported that circular RNAs (circRNAs) play a crucial regulatory role in a variety of human diseases. However, the roles of circRNAs in ankylosing spondylitis (AS) remain unclear. In this study, we conducted circRNA expression profiling of the spinal ligament tissues of patients with AS by RNA sequencing (RNA-seq) and analyzed the potential functions of differentially expressed circRNA by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses to investigate the potential mechanisms associated with AS. The results showed that a total of 1,172 circRNAs were detected in the spinal ligament tissue samples, of which 123 circRNAs were significantly differentially expressed by a fold change ≥ 1.5 and p value < 0.05. Among these, 57 circRNAs were upregulated, and 66 were downregulated. GO and KEGG analyses demonstrated that the differentially expressed circRNAs were mainly involved in the regulation of biological processes of peptidyl-serine phosphorylation and human immune system that may be related to AS. In addition, the circRNA/miRNA interaction networks were established to predict the potential roles of differentially expressed circRNAs by bioinformatics analysis. Taken together, these results revealed the expression profiles of circRNAs and the potential functions of the differentially expressed circRNAs in the spinal ligament tissue of patients with AS, which may provide new clues for understanding the mechanisms associated with AS, and proceed to identify novel potential molecular targets for the diagnoses and treatment of AS.

H19 Increases IL-17A/IL-23 Releases via Regulating VDR by Interacting with miR675-5p/miR22-5p in Ankylosing Spondylitis

Long non-coding RNA (lncRNA) H19 is associated with inflammatory diseases, but the molecular mechanism of H19 in the inflammatory process of ankylosing spondylitis (AS) is unclear. Here, we investigated the role of H19 and its downstream molecules in the inflammation of AS by microarray analysis, qRT-PCR, western blot, and dual-luciferase reporter assay. H19 small interfering RNA (siRNA) (Si-H19) and adenovirus (AD-H19) were used to decrease and increase H19 expression, respectively. 42 annotated lncRNAs were identified, and H19 was overexpressed. H19, vitamin D receptor (VDR), and transforming growth factor β (TGF-β) can bind to microRNA22-5p (miR22-5p) and miR675-5p. Si-H19 significantly downregulated miR22-5p and upregulated miR675-5p expression; Si-H19 decreased the protein and mRNA expression of VDR and decreased the cytokine and mRNA levels of interleukin-17A (IL-17A) and IL-23. These results were verified by AD-H19. In addition, miR22-5p and miR675-5p inhibitors increased the protein and mRNA expression of VDR and increased the cytokine and mRNA levels of IL-17A and IL-23. These results were also confirmed by miRNA mimics. Furthermore, H19 directly interfered with miR22-5p and miR675-5p expression, whereas the two miRNAs directly inhibited VDR expression. Overall, the H19-miR22-5p/miR675-5p-VDR-IL-17A/IL-23 signaling pathways have important roles in the pathogenesis of AS.

Noncoding RNAs Involved in the Pathogenesis of Ankylosing Spondylitis

Ankylosing spondylitis (AS) is a form of arthritis that can lead to fusion of vertebrae and sacroiliac joints following syndesmophyte formation. The etiology of this painful disease remains poorly defined due to its complex genetic background. There are no commonly accepted methods for early diagnosis of AS, nor are there any effective or efficient clinical treatments. Several noncoding RNAs (ncRNAs) have been linked to AS pathogenesis and inflammation via selective binding of their downstream targets. However, major gaps in knowledge remain to be filled before such findings can be translated into clinical treatments for AS. In this review, we outline recent findings that demonstrate essential roles of ncRNAs in AS mediated via multiple signaling pathways such as the Wnt, transforming growth factor-β/bone morphogenetic protein, inflammatory, T-cell prosurvival, and nuclear factor-κB pathways. The summary of these findings provides insight into the molecular mechanisms by which ncRNAs can be targeted for AS diagnosis and the development of therapeutic drugs against a variety of autoimmune diseases.

LINC00311 is overexpressed in ankylosing spondylitis and predict treatment outcomes and recurrence

BACKGROUND

LncRNA LINC00311 participates in osteoporosis, which shows inverse pathological changes to ankylosing spondylitis (AS), indicating that LINC00311 is also involved in AS.

METHODS

All the participants were enrolled in Ganzhou People's Hospital between January 2016 and January 2018 after this study was approved by Ganzhou People's Hospital Ethics Committee. Disease activity determination, follow-up and RT-qPCR were carried out during the research.

RESULTS

In the present study we found that LINC00311 was upregulated in AS patients comparing to healthy controls, and upregulation of LINC00311 distinguished AS patients from healthy controls. LINC00311 expression levels were positively correlated with disease activity. Comparing to pre-treatment levels, LINC00311 expression level decreased significantly after treatment. During 2-year follow-up, patients with high levels of LINC00311 showed a significantly higher rate of rehospitalization.

CONCLUSIONS

Therefore, LINC00311 is overexpressed in AS and predict treatment outcomes and recurrence.

Identification of the key genes and long non‑coding RNAs in ankylosing spondylitis using RNA sequencing

Ankylosing spondylitis (AS) is an insidious and debilitating form of arthritis that involves the axial skeleton, and its etiology and pathogenesis remain unclear. In the present study, three patients with AS and three normal controls from our hospital were enrolled. RNA sequencing and bioinformatics analysis were performed in order to identify the differentially expressed (DE) mRNAs (DEmRNAs) and DE long non‑coding RNAs (DElncRNAs) between the patients with AS and normal controls. Construction of an AS‑specific protein‑protein interaction network, a weighted DElncRNA‑DEmRNA co‑expression network and functional annotation of the DEmRNAs co‑expressed with DElncRNAs was performed. Nearby cis‑targeted DEmRNAs or DElncRNAs were identified by searching for DEmRNAs that were transcribed within 100‑kb up‑ or downstream of DElncRNAs. Based on the Gene Expression Omnibus datasets GSE25101 and GSE73754, the expression of selected DEmRNAs and DElncRNAs were verified using published RNA sequencing data from blood samples, and receiver operating characteristic analysis of selected DEmRNAs was performed. Compared with the normal controls, 1,072 DEmRNAs and 372 DElncRNAs in the patients with AS were identified. Caspase recruitment domain family member 11 and DNA methyltransferase 1 have great diagnostic value for AS. MSTRG.8559 and LINC00987 were also identified as two hub DElncRNAs. The T‑cell receptor signaling pathway was a significantly enriched pathway of the DEmRNAs co‑expressed with DElncRNAs in patients with AS. In conclusion, the present study identified the key DEmRNAs and DElncRNAs in AS, which provides novel information for understanding the pathogenesis of AS and developing potential biomarkers for AS.

lncRNA MEG3 is downregulated in ankylosing spondylitis and associated with disease activity, hospitalization time and disease duration

Long non-coding (lnc)RNA maternally expressed gene 3 (MEG3) has been proved to participate in osteoporosis, which features inverse pathological changes to those associated with spondylosis. The present study aimed to investigate the involvement of lncRNA MEG3 in ankylosing spondylitis. Blood and open sacroiliac joint biopsies were obtained from ankylosing spondylitis patients and healthy controls, and the expression of MEG3 in those tissues was detected by reverse-transcription-quantitative polymerase chain reaction analysis. Disease activity was evaluated according to the Ankylosing Spondylitis Disease Activity Score established by the International Association of Ankylosing Spondylitis. The diagnostic value of MEG3 expression for ankylosing spondylitis was evaluated by receiver operating characteristic curve analysis. The correlation between MEG3 expression and disease activity was assessed using Pearson correlation analysis. Furthermore, according to the median expression level of MEG3, patients were divided into high-level and low-level groups. The hospitalization time and re-hospitalization rate within 2 years after discharge were compared between these two groups and differences in clinicopathological parameters between the two groups were analyzed using the chi-square test. The results indicated that MEG3 was downregulated in ankylosing spondylitis patients compared with that in healthy controls. Furthermore, MEG3 expression levels may be used to effectively distinguish ankylosing spondylitis patients from healthy controls. The serum levels of MEG3 were not associated with the patients' age, sex or alcohol/tobacco consumption, but closely correlated with disease activity and disease duration. In addition, patients with higher expression levels of MEG3 had a shorter hospitalization time and a lower re-hospitalization rate within 2 years after discharge It was concluded that lncRNA MEG3 is downregulated in ankylosing spondylitis patients and is associated with disease activity, time of hospitalization and disease duration.

LncRNAs on guard

Long noncoding RNAs (lncRNAs) are emerging as crucial regulators of gene expression in immune system. It has been reported that lncRNAs participate in regulation of immune responses through both transcriptional and post-transcriptional mechanisms. In this review, we summarize the molecular functions of lncRNAs and discuss their binding to DNA, RNA and protein targets. We focus on the regulatory function of lncRNAs in both innate and adaptive immunity, as well as in autoimmunity and cancer immunology. In addition, we point out the limitation in current knowledge and future directions for the study of lncRNAs in the immune system.

Identification of pathways significantly associated with spondyloarthropathy/ankylosing spondylitis using the sub‑pathway method

The aim of the present study was to extract potential sub-pathway biomarkers for spondyloarthropathy (SpA)/ankylosing spondylitis (AS) using a sub-pathway strategy. SpA/AS-relevant data, reference pathways and long non-coding (lnc)RNA-micro (mi)RNA-mRNA interactions were downloaded. The seed pathways based on Kyoto Encyclopedia of Genes and Genomes pathways and the mRNAs in the co-expressed lncRNA-mRNA interactions were extracted. Sub-pathways regulated by lncRNA were selected after establishing condition-specific lncRNA competitively regulated pathways (LCRP) network. Significant sub-pathways were further identified using the attract method. These significant sub-pathways were evaluated in the other independent published AS microarray data (E-GEOD-25101) using in silico validation. In addition, to uncover SpA/AS-relevant lncRNAs, the degree analysis for all nodes in the LCRP network was conducted. A total of 35 lncRNAs, 131 mRNAs and 145 co-expressed interactions were identified. When entering these 131 mRNAs into the reference pathways, 82 seed pathways were extracted, which were transformed into undirected graphs, and the 35 lncRNAs were mapped to the pathway graphs to further establish the condition-specific LCRP network. Based on degree analysis, four hub lncRNAs were selected, including C14orf169, LINC00242, LINC00116 and LINC00482. It was identified that 35 lncRNAs competitively regulating sub-pathways were involved in 56 complete pathways. Among these, the top three sub-pathways were path: 04010_1, which was a subregion of the mitogen-activated protein kinase (MAPK) signaling pathway; path: 04062-1, an important subregion in the chemokine signaling pathway; and path: 04066_2, was a part of HIF-1 signaling pathway. Furthermore, it was validated consistently in the separate microarray data set E-GEOD-25101. Cancer-associated pathways and hub node C14orf169 were identified in validation. Sub-pathways, including the MAPK signaling pathway and chemokine signaling pathway, and hub lncRNA (C14orf169) may serve important roles in SpA/AS.

Analysis of the miRNA and mRNA involved in osteogenesis of adipose-derived mesenchymal stem cells

Mesenchymal stem cells (MSCs) are bone marrow stromal cells capable of differentiating into different tissue types. Osteoblastic differentiation is a complex process that is critical for bone formation. An increasing number of studies have suggested that microRNAs (miRNAs) may serve important roles in various biological processes, including osteogenesis of MSCs. However, less is known about the participation of particular miRNAs in the osteogenic differentiation of adipose-derived stem cells (ADSCs). In order to identify functional miRNAs and the key genes involved in the osteogenesis of MSCs, the present study reconstructed a global network using data from the National Center for Biotechnology Information Gene Expression Omnibus. Meanwhile, gene ontology and pathway analysis were performed using the Cytoscape plug-in BinGO and the Database for Annotation, Visualization, and Integration Discovery, respectively. An miRNA-mRNA network composed of 72 mRNA and nine miRNA nodes advised by bioinformatics analysis was constructed. These mRNAs and miRNAs were predicted to be involved in the regulation of osteogenic differentiation of ADSCs according to the gene microarray. In the present study, six miRNAs (miR-143-3p, miR-135a-5p, miR-31-5p, miR-22-3p, miR-193b-3p and let-7i-5p) were observed to be highly associated with the osteogenesis of ADSCs, and dihydropyrimidinase like 3 was identified as a novel regulator in this process. These results provide support for further investigations into the management of bone regeneration-associated diseases.

MicroRNA implications in the etiopathogenesis of ankylosing spondylitis

Ankylosing spondylitis (AS) is a chronic immune-mediated inflammatory disease that affects both axial and peripheral skeletons as well as soft tissues. Recent investigations offer that disease pathogenesis is ascribed to a complex interplay of genetic, environmental, and immunological factors. Until now, there is no appropriate method for early diagnosis of AS and the successful available therapy for AS patients stay largely undefined. MicroRNAs (miRNAs), endogenous small noncoding RNAs controlling the functions of target mRNAs and cellular processes, are present in human plasma in a stable form and have appeared as possible biomarkers for activity, pathogenesis, and prognosis of the disease. In the present review, we have tried to summarize the recent findings related to miRNAs in AS development and discuss the possible utilization of these molecules as prognostic biomarkers or important therapeutic strategies for AS. Further examinations are needed to determine the unique miRNAs signatures in AS and characterize the mechanisms mediated by miRNAs in the pathology of this disease.

A Potential Prognostic Long Noncoding RNA Signature to Predict Recurrence among ER-positive Breast Cancer Patients Treated with Tamoxifen

Limited predictable long noncoding RNA (lncRNA) signature was reported in tamoxifen resistance among estrogen receptor (ER)-positive breast cancer (BC) patients. The aim of this study was to identify and assess prognostic lncRNA signature to predict recurrence among ER-positive BC patients treated with tamoxifen. Cohorts from Gene Expression Omnibus (GEO) (n = 298) and The Cancer Genome Atlas (TCGA) (n = 160) were defined as training and validation cohort, respectively. BC relapse associated lnRNAs was identify within training cohort, and the predictable value of recurrence was assessed in both cohorts. A total of 11lncRNAs were recognized to be associated with relapse free survival (RFS) of ER-positive BC patients receiving tamoxifen, who were divided into low-risk and high-risk group on basis of relapse risk scores (RRS). Multivariate cox regression analyses revealed that the RRS is an independent prognostic biomarker in the prediction of ER-positive BC patients' survival. GSEA indicated that high-risk group was associated with several signaling pathways in processing of BC recurrence and metastasis such as PI3K-Akt and Wnt signaling. Our 11-lncRNA based classifier is a reliable prognostic and predictive tool for disease relapse in BC patients receiving tamoxifen.

Overexpression of miR-31 in Peripheral Blood Mononuclear Cells (PBMC) from Patients with Ankylosing Spondylitis

Background

miRNAs play vital roles in regulating immunologic functions and autoimmunity. However, the levels of miR-31, miR-155, miR-16, and miR-181a have not been explored in AS, but were verified to play vital roles in other immunological diseases. The aim of our study was to examine whether the expressions of miR-31, miR-155, miR-16, and miR-181a are abnormal in AS.

Material/Methods

Real-time transcription-polymerase chain reaction analysis (RT-PCR) was used to determine the expression of miR-31, miR-155, miR-16, and miR-181a in peripheral blood mononuclear cells (PBMC) from 40 patients with AS and 40 healthy controls.

Results

The expression of miR-31 was increased in AS patients compared with healthy controls (p=0.001). Furthermore, we detected no significant differences in the expressions of miR-155, miR-16, and miR-181a between AS patients and healthy controls. However, the expression levels of the 4 miRNAs were all significantly different between less active AS and more active AS, with higher levels in more active AS. Moreover, no significant correlations were found between the 4 miRNAs levels with the clinical characteristics in the patients with AS. Interestingly, the expression levels of miR-31, miR-155, and miR-16 in PBMCs were significantly positively correlated with the ESR in new AS patients but not old AS patients.

Conclusions

Our results suggest that miR-31 is overexpressed in PBMCs of AS patients. Furthermore, miR-31, miR-155, miR-16 and miR-181a may be associated with AS disease activity.

Reconstruction and analysis of the lncRNA–miRNA–mRNA network based on competitive endogenous RNA reveal functional lncRNAs in rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune disease with an unknown etiology, occurring in approximately 1.0% of general population.