The Roles of Noncoding RNAs in Systemic Sclerosis

ncRNAs-Mediated Pyroptosis in Cerebral Ischemia-Reperfusion Injury: Pathophysiology, Mechanisms, and Therapeutic Perspectives

Cerebral ischemia-reperfusion injury (CIRI) is a complex pathological process triggered by transient obstruction of blood flow and subsequent reperfusion, ultimately leading to intracellular disturbances such as oxidative stress, inflammatory responses, and programmed cell death. Among the various types of cell death, pyroptosis (an inflammatory kind of regulated cell death) has received increasing attention due to its involvement in key neurovascular unit cells, including endothelial cells, neurons, microglia, and astrocytes. Intriguingly, accumulating evidence demonstrates that non-coding RNAs (ncRNAs), including long non-coding RNAs, microRNAs, and circular RNAs, can modulate multiple stages of pyroptosis in CIRI. This review synthesizes recent findings on the ncRNAs-regulated pyroptosis in CIRI. We highlight the molecular underpinnings of pyroptotic activation following ischemic injury and discuss how ncRNAs shape these mechanisms. By elucidating the interactions between ncRNAs and pyroptosis-related pathways, we intend to present innovative viewpoints for early diagnosis and the development of potential therapeutic strategies to mitigate CIRI.

MiR-4769-3p suppresses adipogenesis in systemic sclerosis by negatively regulating the USP18/VDAC2 pathway

Systemic sclerosis (SSc) is an autoimmune disease affecting multiple tissues. The underlying causes and mechanisms of subcutaneous adipose tissue (SAT) loss in SSc remain unclear. Recent studies have highlighted the role of microRNAs in adipogenesis. Our study found that miR-4769-3p was upregulated in SSc patients and its silencing promoted SAT recovery in bleomycin-induced SSc mice, suggesting that miR-4769-3p might affect adipogenesis in SSc. Manipulating miR-4769-3p expression in 3T3-L1 cells revealed that its inhibition enhanced adipogenesis, while its overexpression weakened it. Further investigations showed that miR-4769-3p bound to 3'UTR of ubiquitin-specific protease-18 (USP18), inhibiting its expression, while USP18 interacted with voltage-dependent anion channel-2 (VDAC2), both of which were reduced in SSc. Silencing either USP18 or VDAC2 attenuated adipogenesis. Notably, USP18 inhibited VDAC2 ubiquitination and degradation, whereas miR-4769-3p reversed the VDAC2-induced elevation of adipogenesis, suggesting that miR-4769-3p inhibited adipogenesis by negatively regulating the USP18/VDAC2 pathway, providing a potential therapeutic target for SSc.

Recent Insights into Cellular and Molecular Mechanisms of Defective Angiogenesis in Systemic Sclerosis

In systemic sclerosis (SSc, or scleroderma), defective angiogenesis, clinically manifesting with abnormal capillary architecture and severe capillary reduction, represents a hallmark of early-stage disease, usually preceding the onset of tissue fibrosis, and is caused by several cellular and molecular mechanisms affecting microvascular endothelial cells with different outcomes. Indeed, once damaged, endothelial cells can be dysfunctionally activated, thus becoming unable to undergo angiogenesis and promoting perivascular inflammation. They can also undergo apoptosis, transdifferentiate into profibrotic myofibroblasts, or acquire a senescence-associated secretory phenotype characterized by the release of exosomes and several profibrotic and proinflammatory mediators. In this narrative review, we aimed to give a comprehensive overview of recent studies dealing with the cellular and molecular mechanisms underlying SSc defective angiogenesis and the related endothelial cell dysfunctions, mainly the endothelial-to-mesenchymal transition process. We also discussed potential novel vascular treatment strategies able to restore the angiogenic process and reduce the endothelial-to-mesenchymal transition in this complex disease.

Cellular Transdifferentiation: A Crucial Mechanism of Fibrosis in Systemic Sclerosis

Systemic Sclerosis (SSc) is a systemic autoimmune disease of unknown etiology with a highly complex pathogenesis that despite extensive investigation is not completely understood. The clinical and pathologic manifestations of the disease result from three distinct processes: 1) Severe and frequently progressive tissue fibrosis causing exaggerated and deleterious accumulation of interstitial collagens and other extracellular matrix molecules in the skin and various internal organs; 2) extensive fibroproliferative vascular lesions affecting small arteries and arterioles causing tissue ischemic alterations; and 3) cellular and humoral immunity abnormalities with the production of numerous autoantibodies, some with very high specificity for SSc. The fibrotic process in SSc is one of the main causes of disability and high mortality of the disease. Owing to its essentially universal presence and the severity of its clinical effects, the mechanisms involved in the development and progression of tissue fibrosis have been extensively investigated, however, despite intensive investigation, the precise molecular mechanisms have not been fully elucidated. Several recent studies have suggested that cellular transdifferentiation resulting in the phenotypic conversion of various cell types into activated myofibroblasts may be one important mechanism. Here, we review the potential role that cellular transdifferentiation may play in the development of severe and often progressive tissue fibrosis in SSc.

[Medical visit status and clinical features in patients with IgG4 related disease]

OBJECTIVE

To understand the medical treatment and clinical characteristics of patients with IgG4-related disease (IgG4-RD) with complex clinical manifestations and easy to be misdiagnosed and missed, and to improve the recognition of this disease among doctors from relevant medical departments.

METHODS

A retrospective analysis was conducted on the medical records of patients diagnosed with IgG4-RD who were hospitalized and discharged from Peking University Third Hospital from January 1, 2012 to December 31, 2022. The patient' s medical visit status, clinical manifestations, laboratory examinations, diagnosis, and treatment information were summarized.

RESULTS

A total of 116 patients diagnosed with IgG4-RD were included in this study, with a male to female ratio of 2. 52∶ 1 and an average age of (61.83±10.80) years. The departments for initial visits were gastroenterology, general surgery, and ophthalmology. While the departments responsible for definitive diagnosis were gastroenterology, rheumatology and immunology, and respiratory medicine. Twenty-one patients (18. 10%) required consultation and treatment from three or more departments before receiving a definitive diagnosis. The median time from symptom onset to the initial clinic visit was 2 (1, 7) months, and the median time from symptom onset to diagnosis was 1 (1, 12) month. Twenty-four patients (20.69%) underwent surgical resection of the affected sites before diagnosis. According to the classification criteria of IgG4-RD, sixty-eight (58.62%) cases were diagnosed definitively, eight (6.9%) cases were likely to be diagnosed, and 40 (34.48%) cases were suspected to be diagnosed. In the 68 definitively diagnosed patients, the most commonly affected organs were submandibular gland, the pancreas, biliary tract, parotid in sequence. The median serum IgG4 (IgG4, immunoglobulin G4) level was 6.16 (3. 61, 12. 30) g/L. Fifty-seven patients (83.82%) were treated with glucocorticoids, and 14 patients (20.59%) were treated with immunosuppressants. The use of immunosuppressants was mainly in the rheumatology and immunology department (78. 57%).

CONCLUSION

IgG4-RD is more common in elderly males, with submandibular gland, the pancreas, biliary tract, and parotid being most commonly affected. The distribution of initial visit departments in patients is wide. The proportion of definitive diagnosis based on pathology is relatively low. In terms of treatment, the main approach is steroid treatment, while the use of immunosuppres-sants is not widespread.

[Expression and clinical significance of plasma exosomal miR-34-5p and miR-142-3p in systemic sclerosis]

OBJECTIVE

To detect the expression of plasma exosomal microRNA (miRNA) in systemic sclerosis (SSc), and to investigate its clinical significance.

METHODS

A total of 20 patients who were initially diagnosed with SSc and did not receive medication in Department of Rheumatology and Immunology of Meizhou People' s Hospital from January 2020 to January 2022 were recruited, as well as 15 healthy individuals whose gender and age matched with those of the SSc patients. Plasma exosomes were isolated using ultracentrifugation method. The expression levels of exosomal miR-34-5p, miR-92-3p and miR-142-3p were detected by quantative real-time polymerase chain reaction (qRT-PCR). Correlations between the expression levels of exosomal miRNAs and clinical characteristic were analyzed by Spearman's rank correlation coefficient test.

RESULTS

The mean age of 20 patients with SSc was (52.6±12.6) years, including 7 males and 13 females. Among the 20 SSc patients, 13 cases were diagnosed as limited cutaneous systemic sclerosis (lcSSc) and 7 cases were diagnosed as diffuse cutaneous systemic sclerosis (dcSSc) according to the extent of skin involvement. According to the findings of high resolution chest CT, 7 of 20 SSc patients were diagnosed with interstitial lung disease (ILD) and 13 SSc patients were diagnosed with non-ILD. The expression levels of exosomal miR-34-5p, miR-92-3p and miR-142-3p were significantly elevated in the SSc patients compared with those in the healthy controls group (P=0.003, P=0.000 1, and P=0.016, respectively). Compared with the SSc patients without ILD, the expression levels of miR-34-5p and miR-142-3p were significantly lower in the SSc patients with ILD (P=0.037 and P=0.015, respectively). The expression levels of exosomal miR-34-5p and miR-142-3p showed negative correlation with ILD (r=-0.48, P=0.031 and r=-0.55, P=0.011, respectively), and arthritis (r=-0.46, P=0.040 and r=-0.48, P=0.032, respectively). The expression levels of exosomal miR-142-3p showed a negative correlation with erythrocyte sedimentation rate (ESR) (r=-0.55, P=0.012).

CONCLUSION

Plasma exosomal miR-34-5p, miR-92-3p and miR-142-3p were dysregulated in SSc. The dyregulation of exosomal miR-34-5p and miR-142-3p showed correlation with SSc associated ILD (SSc-ILD).

Mechanism of action of non-coding RNAs and traditional Chinese medicine in myocardial fibrosis: Focus on the TGF-β/Smad signaling pathway

Cardiac fibrosis is a serious public health problem worldwide that is closely linked to progression of many cardiovascular diseases (CVDs) and adversely affects both the disease process and clinical prognosis. Numerous studies have shown that the TGF-β/Smad signaling pathway plays a key role in the progression of cardiac fibrosis. Therefore, targeted inhibition of the TGF-β/Smad signaling pathway may be a therapeutic measure for cardiac fibrosis. Currently, as the investigation on non-coding RNAs (ncRNAs) move forward, a variety of ncRNAs targeting TGF-β and its downstream Smad proteins have attracted high attention. Besides, Traditional Chinese Medicine (TCM) has been widely used in treating the cardiac fibrosis. As more and more molecular mechanisms of natural products, herbal formulas, and proprietary Chinese medicines are revealed, TCM has been proven to act on cardiac fibrosis by modulating multiple targets and signaling pathways, especially the TGF-β/Smad. Therefore, this work summarizes the roles of TGF-β/Smad classical and non-classical signaling pathways in the cardiac fibrosis, and discusses the recent research advances in ncRNAs targeting the TGF-β/Smad signaling pathway and TCM against cardiac fibrosis. It is hoped, in this way, to give new insights into the prevention and treatment of cardiac fibrosis.

Construction of a cuproptosis-related lncRNA signature for predicting prognosis and immune landscape in osteosarcoma patients

BACKGROUND

Long noncoding RNAs (lncRNAs) influence the onset of osteosarcoma. Cuproptosis is a novel cell death mechanism. We attempted to identify a cuproptosis-related lncRNA signature to predict the prognosis and immune landscape in osteosarcoma patients.

METHODS

Transcriptional and clinical data of 85 osteosarcoma patients were derived from the TARGET database and randomly categorized into the training and validation cohorts. We implemented the univariate and multivariate Cox regression, along with LASSO regression analyses for developing a cuproptosis-related lncRNA risk model. Kaplan-Meier curves, C-index, ROC curves, univariate and multivariate Cox regression, and nomogram were used to assess the capacity of this risk model to predict the osteosarcoma prognosis. Gene ontology, KEGG, and Gene Set Enrichment (GSEA) analyses were conducted for determining the potential functional differences existing between the high-risk and low-risk patients. We further conducted the ESTIMATE, single-smaple GSEA, and CIBERSORT analyses for identifying the different immune microenvironments and immune cells infiltrating both the risk groups.

RESULTS

We screened out four cuproptosis-related lncRNAs (AL033384.2, AL031775.1, AC110995.1, and LINC00565) to construct the risk model in the training cohort. This risk model displayed a good performance to predict the overall survival of osteosarcoma patients, which was confirmed by using the validation and the entire cohort. Further analyses showed that the low-risk patients have more immune activation and immune cells infiltrating as well as a good response to immunotherapy.

CONCLUSIONS

We developed a novel cuproptosis-related lncRNA signature with high reliability and accuracy for predicting outcome and immunotherapy response in osteosarcoma patients, which provides new insights into the personalized treatment of osteosarcoma.

Identification of lncRNA-miRNA-mRNA networks in circulating exosomes as potential biomarkers for systemic sclerosis

Objective

This study aimed to analyze potential biomarkers for systemic sclerosis (SSc) by constructing lncRNA-miRNA-mRNA networks in circulating exosomes (cirexos).

Materials and methods

Differentially expressed mRNAs (DEmRNAs) and lncRNAs (DElncRNAs) in SSc cirexos were screened using high-throughput sequencing and detected with real-time quantitative PCR (RT-qPCR). Differentially expressed genes (DEGs) were analyzed using the DisGeNET, GeneCards, GSEA4.2.3, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. Receiver operating characteristic (ROC) curves, correlation analyses, and a double-luciferase reporter gene detection assay were used to analyze competing endogenous RNA (ceRNA) networks and clinical data.

Results

In this study, 286 DEmRNAs and 192 DElncRNAs were screened, of which 18 DEGs were the same as the SSc-related genes. The main SSc-related pathways included extracellular matrix (ECM) receptor interaction, local adhesion, platelet activation, and IgA production by the intestinal immune network. A hub gene, COL1A1, was obtained by a protein-protein interaction (PPI) network. Four ceRNA networks were predicted through Cytoscape. The relative expression levels of COL1A1, ENST0000313807, and NON-HSAT194388.1 were significantly higher in SSc, while the relative expression levels of hsa-miR-29a-3p, hsa-miR-29b-3p, and hsa-miR-29c-3p were significantly lower in SSc (P < 0.05). The ROC curve showed that the ENST00000313807-hsa-miR-29a-3p-COL1A1 network as a combined biomarker of SSc is more valuable than independent diagnosis, and that it is correlated with high-resolution CT (HRCT), Scl-70, C-reactive protein (CRP), Ro-52, IL-10, IgM, lymphocyte percentage, neutrophil percentage, albumin divided by globulin, urea, and RDW-SD (P < 0.05). Double-luciferase reporter gene detection showed that ENST00000313807 interacts with hsa-miR-29a-3p, which interacts with COL1A1.

Conclusion

The ENST00000313807-hsa-miR-29a-3p-COL1A1 network in plasma cirexos represents a potential combined biomarker for the clinical diagnosis and treatment of SSc.

Construction of a Prognostic Model Based on Cuproptosis-Related lncRNA Signatures in Pancreatic Cancer

Aim

The aim of this study is to identify cuproptosis-related lncRNAs and construct a prognostic model for pancreatic cancer patients for clinical use.

Methods

The expression profile of lncRNAs was downloaded from The Cancer Genome Atlas database, and cuproptosis-related lncRNAs were identified. The prognostic cuproptosis-related lncRNAs were obtained and used to establish and validate a prognostic risk score model in pancreatic cancer.

Results

In total, 181 cuproptosis-related lncRNAs were obtained. The prognostic risk score model was constructed based on five lncRNAs (AC025257.1, TRAM2-AS1, AC091057.1, LINC01963, and MALAT1). Patients were assigned to two groups according to the median risk score. Kaplan-Meier survival curves showed that the difference in the prognosis between the high- and low-risk groups was statistically significant. Multivariate Cox analysis showed that our risk score was an independent risk factor for pancreatic cancer patients. Receiver operator characteristic curves revealed that the cuproptosis-related lncRNA model can effectively predict the prognosis of pancreatic cancer. The principal component analysis showed a difference between the high- and low-risk groups intuitively. Functional enrichment analysis showed that different genes were involved in cancer-related pathways in patients in the high- and low-risk groups.

Conclusion

The risk model based on five prognostic cuproptosis-related lncRNAs can well predict the prognosis of pancreatic cancer patients. Cuproptosis-related lncRNAs could be potential biomarkers for pancreatic cancer diagnosis and treatment.

Endoglin and Systemic Sclerosis: A PRISMA-driven systematic review

Background

Systemic Sclerosis (SSc) is a rare autoimmune disease whose pathogenesis is still poorly understood. The Transforming Growth Factor β superfamily is considered pivotal and a crucial role has been suggested for the type III receptor, Endoglin (ENG). The aim of this systematic review is to investigate and combine the current clinical and molecular available data, to suggest novel hints for further studies.

Methods

We followed PRISMA guidelines; the search was performed on three databases (MEDLINE, Web of Science, Embase) in date November 2nd, 2021. Subsequent to the exclusion of duplicates, we applied as inclusion criteria: 1. focus on the relationship between ENG and SSc; 2. English language. As exclusion criteria: 1. ENG exclusively as a cellular biomarker; 2. no focus on ENG-SSc relationship; 3. review articles and 4. abstracts that did not add novel data. Eligibility was assessed independently by each author to reduce biases. We divided records into clinical and molecular works and subgrouped them by their study features and aim.

Results

We selected 25 original papers and 10 conference abstracts. Molecular studies included 6 articles and 4 abstracts, whereas clinical studies included 17 articles and 6 abstracts; 2 articles presented both characteristics. Molecular studies were focussed on ENG expression in different cell types, showing an altered ENG expression in SSc-affected cells. Clinical studies mainly suggested that different disease phenotypes can be related to peculiar disregulations in soluble ENG concentrations.

Discussion

Concerning the possible limits of our search, boolean operators in our strings might have been uneffective. However, the use of different strings in different databases should have reduced this issue at a minimum. Another bias can be represented by the selection step, in which we excluded many articles based on the role of Endoglin as a histological vascular marker rather than a signaling receptor. We tried to reduce this risk by performing the selection independently by each author and discussing disagreements. Our systematic review pointed out that ENG has a pivotal role in activating different TGFβ-stimulated pathways that can be crucial in SSc pathogenesis and progression.