LncRNA PlncRNA-1 participates in rheumatoid arthritis by regulating transforming growth factor β1

Long non-coding RNAs as pathophysiological regulators, therapeutic targets and novel extracellular vesicle biomarkers for the diagnosis of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic relapsing disease of the gastrointestinal (GI) system that includes two groups, Crohn's disease (CD) and ulcerative colitis (UC). To cope with these two classes of IBD, the investigation of pathogenic mechanisms and the discovery of new diagnostic and therapeutic approaches are crucial. Long non-coding RNAs (lncRNAs) which are non-coding RNAs with a length of longer than 200 nucleotides have indicated significant association with the pathology of IBD and strong potential to be used as accurate biomarkers in diagnosing and predicting responses to the IBD treatment. In the current review, we aim to investigate the role of lncRNAs in the pathology and development of IBD. We first describe recent advances in research on dysregulated lncRNAs in the pathogenesis of IBD from the perspective of epithelial barrier function, intestinal immunity, mitochondrial function, and intestinal autophagy. Then, we highlight the possible translational role of lncRNAs as therapeutic targets, diagnostic biomarkers, and predictors of therapeutic response in colon tissues and plasma samples. Finally, we discuss the potential of extracellular vesicles and their lncRNA cargo in the pathophysiology, diagnosis, and treatment of IBD.

Unveiling Novel Drug Targets and Emerging Therapies for Rheumatoid Arthritis: A Comprehensive Review

Rheumatoid arthritis (RA) is a chronic debilitating autoimmune disease, that causes joint damage, deformities, and decreased functionality. In addition, RA can also impact organs like the skin, lungs, eyes, and blood vessels. This autoimmune condition arises when the immune system erroneously targets the joint synovial membrane, resulting in synovitis, pannus formation, and cartilage damage. RA treatment is often holistic, integrating medication, physical therapy, and lifestyle modifications. Its main objective is to achieve remission or low disease activity by utilizing a "treat-to-target" approach that optimizes drug usage and dose adjustments based on clinical response and disease activity markers. The primary RA treatment uses disease-modifying antirheumatic drugs (DMARDs) that help to interrupt the inflammatory process. When there is an inadequate response, a combination of biologicals and DMARDs is recommended. Biological therapies target inflammatory pathways and have shown promising results in managing RA symptoms. Close monitoring for adverse effects and disease progression is critical to ensure optimal treatment outcomes. A deeper understanding of the pathways and mechanisms will allow new treatment strategies that minimize adverse effects and maintain quality of life. This review discusses the potential targets that can be used for designing and implementing precision medicine in RA treatment, spotlighting the latest breakthroughs in biologics, JAK inhibitors, IL-6 receptor antagonists, TNF blockers, and disease-modifying noncoding RNAs.

Biomarkers (mRNAs and non-coding RNAs) for the diagnosis and prognosis of rheumatoid arthritis

In recent years, diagnostic and therapeutic approaches for rheumatoid arthritis (RA) have continued to improve. However, in the advanced stages of the disease, patients are unable to achieve long-term clinical remission and often suffer from systemic multi-organ damage and severe complications. Patients with RA usually have no overt clinical manifestations in the early stages, and by the time a definitive diagnosis is made, the disease is already at an advanced stage. RA is diagnosed clinically and with laboratory tests, including the blood markers C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) and the autoantibodies rheumatoid factor (RF) and anticitrullinated protein antibodies (ACPA). However, the presence of RF and ACPA autoantibodies is associated with aggravated disease, joint damage, and increased mortality, and these autoantibodies have low specificity and sensitivity. The etiology of RA is unknown, with the pathogenesis involving multiple factors and clinical heterogeneity. The early diagnosis, subtype classification, and prognosis of RA remain challenging, and studies to develop minimally invasive or non-invasive biomarkers in the form of biofluid biopsies are becoming more common. Non-coding RNA (ncRNA) molecules are composed of long non-coding RNAs, small nucleolar RNAs, microRNAs, and circular RNAs, which play an essential role in disease onset and progression and can be used in the early diagnosis and prognosis of RA. In this review of the diagnostic and prognostic approaches to RA disease, we provide an overview of the current knowledge on the subject, focusing on recent advances in mRNA-ncRNA as diagnostic and prognostic biomarkers from the biofluid to the tissue level.

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

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

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.

Knockdown of circ-PRKCH alleviates IL-1β-treated chondrocyte cell phenotypic changes through modulating miR-502-5p/ADAMTS5 axis

BACKGROUND

Osteoarthritis (OA) is a common joint disease characterized by progressive cartilage degradation. Circular RNAs (circRNAs) are involved in the initiation and development of OA. This study aimed to explore the potential role and mechanism of circRNA protein kinase C eta (circ-PRKCH) in OA.

METHODS

A total of 30 cartilage specimens were collected from OA patients or normal subjects. Human chondrocytes (CHON-001) were stimulated with interleukin-1β (IL-1β) to establish an in vitro OA model. The expression levels of circ-PRKCH, microRNA-502-5p (miR-502-5p) and circ-PRKCH or A disintegrin and metalloproteases metallopeptidase with thrombospondin type 1 motif 5 (ADAMTS5) in cartilage specimens and IL-1β-treated chondrocytes were detected by quantitative real-time PCR or Western blot, and their correlation in OA cartilage specimens was analysed by Spearman's correlation coefficient. The targeted relationship between miR-502-5p and circ-PRKCH or ADAMTS5 was verified by dual-luciferase reporter assay and RNA Immunoprecipitation (RIP) assay. Cell Counting Kit-8 (CCK-8), 5-Ethynyl-2'-deoxyuridine (EDU), flow cytometry, wound healing and enzyme-linked immunosorbent assay (ELISA) assays were applied to evaluate cell proliferation, apoptosis, migration and inflammatory response in IL-1β-treated chondrocytes. Exosomes were identified by transmission electron microscope (TEM) and Western blot.

RESULTS

Circ-PRKCH and ADAMTS5 expression levels were up-regulated, while miR-502-5p expression was down-regulated in OA cartilage tissues and IL-1β-treated chondrocytes. Depletion of circ-PRKCH relieved IL-1β-treated chondrocyte cell phenotypic changes by promoting cell proliferation and migration, as well as inhibiting apoptosis and inflammatory response. Mechanically, circ-PRKCH acted as a sponge for miR-502-5p to regulate ADAMTS5 expression, thereby contributing to IL-1β-treated chondrocyte cell phenotypic changes. Moreover, exosomes derived from IL-1β-treated chondrocytes could transfer circ-PRKCH across cells.

CONCLUSION

Circ-PRKCH contributed to IL-1β-treated cell phenotypic changes in chondrocytes via modulating miR-502-5p/ADAMTS5 pathway, which might provide a promising biomarker for OA treatment.

LncRNA Expression Profiles in Systemic Lupus Erythematosus and Rheumatoid Arthritis: Emerging Biomarkers and Therapeutic Targets

Systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) are two common multisystem autoimmune diseases that share, among others, many clinical manifestations and serological features. The role of long non-coding RNAs (lncRNAs) has been of particular interest in the pathogenesis of autoimmune diseases. Here, we aimed to summarize the roles of lncRNAs as emerging novel biomarkers and therapeutic targets in SLE and RA. We conducted a narrative review summarizing original articles on lncRNAs associated with SLE and RA, published until November 1, 2021. Based on the studies on lncRNA expression profiles in samples (including PBMCs, serum, and exosomes), it was noted that most of the current research is focused on investigating the regulatory mechanisms of these lncRNAs in SLE and/or RA. Several lncRNAs have been hypothesized to play key roles in these diseases. In SLE, lncRNAs such as GAS5, NEAT1, TUG1, linc0949, and linc0597 are dysregulated and may serve as emerging novel biomarkers and therapeutic targets. In RA, many validated lncRNAs, such as HOTAIR, GAS5, and HIX003209, have been identified as promising novel biomarkers for both diagnosis and treatment. The shared lncRNAs, for example, GAS5, may participate in SLE pathogenesis through the mitogen-activated protein kinase pathway and trigger the AMP-activated protein kinase pathway in RA. Here, we summarize the data on key lncRNAs that may drive the pathogenesis of SLE and RA and could potentially serve as emerging novel biomarkers and therapeutic targets in the coming future.

MicroRNA-4423-3p inhibits proliferation of fibroblast-like synoviocytes by targeting matrix metalloproteinase 13 in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease that is increasing in incidence worldwide. RA is regulated by a variety of microRNAs (miRNAs/miR). Moreover, analysis of public data has revealed that miR-4423-3p is significantly downregulated in peripheral blood mononuclear cells of RA patients. This study investigated the role of miR-4423-3p in RA. The levels of miR-4423-3p and matrix metalloproteinase 13 (MMP13) in RA patients and the regulatory relationship between miR-4423-3p and MMP13 were analyzed using public data. A dual-luciferase reporter assay was performed to verify that miR-4423-3p targets MMP13 in human fibroblast-like synoviocyte (HFLS) RA cells (HFLS-RA). Following the overexpression of miR-4423-3p, miR-4423-3p inhibitor, and MMP13 in HFLS-RA, viability, proliferation, cell cycle, apoptosis, and invasion/migration assays were used to detect the effects of miR-4423-3p targeting MMP13 on cell biological processes. The results revealed that miR-4423-3p was downregulated in peripheral blood mononuclear cells of RA patients and MMP13 was upregulated in synovial tissue of RA patients. miR-4423-3p targets the 3' untranslated region of MMP13 and downregulates MMP13 expression. After overexpression of miR-4423-3p, cell proliferation, migration, and invasion were inhibited, the cell cycle was prevented and cell apoptosis was promoted. Overexpression of MMP13 promoted cell proliferation, migration, and invasion, while accelerating the cell cycle process and suppressing apoptosis. The findings indicate that in HFLS-RA cells, overexpression of miR-4423-3p inhibited proliferation, migration, and invasion, and promoted apoptosis by negatively regulating MMP13. The overexpression of miR-4423-3p might be a novel strategy for the treatment of RA.

Promising Therapeutic Targets for Treatment of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a systemic poly-articular chronic autoimmune joint disease that mainly damages the hands and feet, which affects 0.5% to 1.0% of the population worldwide. With the sustained development of disease-modifying antirheumatic drugs (DMARDs), significant success has been achieved for preventing and relieving disease activity in RA patients. Unfortunately, some patients still show limited response to DMARDs, which puts forward new requirements for special targets and novel therapies. Understanding the pathogenetic roles of the various molecules in RA could facilitate discovery of potential therapeutic targets and approaches. In this review, both existing and emerging targets, including the proteins, small molecular metabolites, and epigenetic regulators related to RA, are discussed, with a focus on the mechanisms that result in inflammation and the development of new drugs for blocking the various modulators in RA.

The lncRNA PVT1/miR-590-5p/FSTL1 axis modulates the proliferation and migration of airway smooth muscle cells in asthma

OBJECTIVE

Asthma is a prevalent chronic inflammatory airway disease that is characterised by airway remodelling and airway hyperresponsiveness. Abnormal proliferation and migration of airway smooth muscle cells (ASMCs) contribute to airway remodelling in asthma. However, the molecular mechanism underlying an increased ASMC mass in asthma remains elusive. Herein, we aimed at investigating the regulation of lncRNA PVT1 on ASMCs and focussing on the mechanism in the proliferation and migration.

METHODS

Expression levels of lncRNA PVT1 and miR-590-5p in the serum collected from 24 children with asthma and 10 control children were determined by qRT-PCR. ASMCs proliferation and migration prior to and post platelet-derived growth factor subunit B (PDGF-BB) stimulation were examined by CCK-8 test and transwell assay. Dual-luciferase reporter assay was performed to determine miR-590-5p interaction with lncRNA PVT1 and follistatin-like 1 (FSTL1). Expression of lncRNA PVT1, miR-590-5p, FSTL1, C-Myc, cyclin D1, and cyclin-dependent kinase 1 (CDK1) was tested by quantitative real-time PCR (qRT-PCR) and immunoblotting analysis.

RESULTS

The expression level of lncRNA PVT1 was higher but the expression level of miR-590-5p was lower in the serum of children with asthma than in control children. The expression level of lncRNA PVT1 was negatively correlated with the expression level of miR-590-5p in asthma. LncRNA PVT1 was upregulated upon PDGF-BB stimulation. LncRNA PVT1 knockdown by its specific shRNA repressed PDGF-BB-induced promotion of proliferation and migration in ASMCs and triggered an elevated miR-590-5p along with declined C-Myc, cyclin D1, and CDK1. The effects of lncRNA PVT1 knockdown on PDGF-BB-induced ASMCs were lost upon miR-590-5p inhibition. MiR-590-5p targeted FSTL1 gene and declined its expression, thus suppressing ASMC proliferation and migration following PDGF-BB stimulation and downregulating C-Myc, cyclin D1, and CDK1 expressions. The effects of miR-590-5p on PDGF-BB-induced ASMCs were lost upon FSTL1 overexpression.

CONCLUSION

These results support the notion that the lncRNA PVT1/miR-590-5p/FSTL1 axis modulates ASMCs proliferation and migration following PDGF-BB stimulation, providing a potential therapeutic target to attenuate airway remodelling in asthma.

Knockdown of 91 H Suppresses the Tumorigenesis of Osteosarcoma via Inducing Methylation of CDK4 Promoter

Background:

Osteosarcoma is the most leading primary malignancy of the bone in adolescents all over the world. Long non-coding RNA (lncRNA) 91 H has been reported to participated in multiple cancers. Meanwhile, lncRNA 91 H has been proved to be upregulated in osteosarcoma. However, the function of 91 H in osteosarcoma remains unclear.

Methods:

Gene and protein expressions in osteosarcoma cells were detected by qRT-PCR and western blot, respectively. Cell viability was tested by CCK-8 assay. Ki67 staining was used to measure cell proliferation. Cell apoptosis and cycle were assessed by flow cytometry. In addition, transwell assay was used to detect cell migration and invasion. Furthermore, Methylation-specific PCR (MSP) was performed to test the methylation of CDK4 promoter. Finally, xenograft mice model was established to explore the role of 91 H in osteosarcoma in vivo.

Results:

Knockdown of 91 H significantly inhibited the growth of osteosarcoma cells via inducing the cell apoptosis. In addition, 91 H siRNA notably suppressed the migration and invasion of osteosarcoma cells. Meanwhile, knockdown of 91 H inhibited the progression of osteosarcoma via inducing methylation of CDK4 promoter. Furthermore, 91 H knockdown obviously induced G1 arrest in osteosarcoma cells via inhibition of PCNA and Cyclin D1. Finally, knockdown of 91 H notably inhibited the tumor growth of osteosarcoma in vivo.

Conclusion:

knockdown of 91 H suppressed the tumorigenesis of osteosarcoma via inducing methylation of CDK4 promoter in vitro and in vivo. Thus, 91 H may serve as a new target for the treatment of osteosarcoma.

LncRNA GAS5 alleviates rheumatoid arthritis through regulating miR-222-3p/Sirt1 signalling axis

INTRODUCTION

Rheumatoid arthritis (RA) is an autoimmune disease that affects millions of people. Fibroblast-like synoviocytes (FLSs) located in rheumatoid panni play a pivotal role in the formation of RA. The long noncoding RNA (lncRNA) GAS5 is reportedly downregulated in rheumatoid arthritis. However, its detailed mechanism in RA remains to be explored. This study investigated the roles and related mechanisms of GAS5 in RA.

METHODS

The expression levels of GAS5, miR-222-3p, and sirtuin 1 (Sirt1) were evaluated by quantitative PCR (qPCR). Cell proliferation was analyzed by CCK-8 and BrdU assays. Cell apoptosis was assessed by flow cytometry and western blotting. Enzyme-linked immunosorbent assay (ELISA) was utilized to evaluate the levels of TNF-α, IL-1β, and IL-6. The interaction between GAS5 or Sirt1 and miR-222-3p was predicted by starBase and validated by dual-luciferase reporter assay.

RESULTS

GAS5 expression was found to be downregulated in the serum samples of RA patients and in RA-FLSs. GAS5 overexpression or the inhibition of miR-222-3p impeded the activity of RA-FLSs by repressing their proliferation and inflammation and by promoting apoptosis. Mechanistically, GAS5 indirectly regulates Sirt1 expression by binding miR-222-3p. Further experiments confirmed that Sirt1 overexpression restored the anti-RA activity of GAS5 under miR-222-3p mimic.

CONCLUSIONS

The miR-222-3p/Sirt1 axis was found to be critical for the function of GAS5 in regulating the proliferation, inflammation, and apoptosis of RA-FLSs. These data indicate GAS5 activation as a potential therapeutic strategy for RA progression.