Serum IgA levels for predicting the development of rapidly progressive interstitial lung disease in dermatomyositis.

BACKGROUND: Some patients with dermatomyositis (DM) can develop rapidly progressive interstitial lung disease (RPILD) that is resistant to treatment and life-threatening. Convenient and practical predictive factors for the development of RPILD are currently lacking. We aimed to identify independent risk factors for RPILD in patients with DM. METHODS: A total of 71 patients with DM admitted to our hospital between July 2018 and July 2022 were retrospectively reviewed. Risk factors to predict RPILD were identified by univariate and multivariate regression analyses, and significant variates for RPILD were included to establish a risk model. RESULTS: Multivariate regression analysis revealed that the risk of RPILD was significantly associated with serum IgA levels. The area under the risk model curve, established by IgA levels combined with other independent predictors including the anti-melanoma differentiation-associated gene 5 (MDA5) antibody, fever, and C-reactive protein, was 0.935 (P < 0.001). CONCLUSION: A higher serum IgA level was identified as an independent risk factor for RPILD in patients with DM.

Circ-CPSF1 Worsens Radiation-Induced Oxidative Stress Injury in Caenorhabditis elegans.

Radioactive substances have been used in various aspects in daily life. However, high-energy radiation could cause environmental problems, which would damage the human body. Circular RNA (CircRNA) has great potential in the minimization of ionizing radiation damage. To find a potential diagnostic and therapeutic target for reducing the damage of ionizing radiation, we selected circRNA cleavage and polyadenylation specificity factor subunit 1 (circ-CPSF1) based on its up-regulated expression after X-ray radiation and explored its effect on response to ionizing radiation using Caenorhabditis elegans (C. elegans). Circ-CPSF1 was screened out and its up-regulated expression was verified. The measurement of lifespan and germ cell apoptosis showed that circ-CPSF1 RNAi treatment extended lifespan and reduced apoptotic germ cells. ROS levels were significantly reduced after the interference of circ-CPSF1 in C. elegans with radiation. Mitochondrial membrane potential assay showed that the suppression of circ-CPSF1 could alleviate mitochondrial damage after radiation. Relative genes expression showed the involvement of circ-CPSF1 in radiation mediated DNA damage response pathways and apoptosis pathways. In conclusion, circ-CPSF1 exerts deleterious effects on lifespan, eggs production and germ cell apoptosis of C. elegans through oxidative stress, the DNA damage response (DDR) pathway, and the core apoptotic pathway after ionizing radiation, indicating the potential of circ-CPSF1 to be an important therapeutic target of radiation damage.

Advanced oxidation protein products induce inflammatory responses and invasive behaviour in fibroblast-like synoviocytes via the RAGE-NF-κB pathway.

AIMS: Rheumatoid arthritis (RA), which mainly results from fibroblast-like synoviocyte (FLS) dysfunction, is related to oxidative stress. Advanced oxidation protein products (AOPPs), which are proinflammatory mediators and a novel biomarker of oxidative stress, have been observed to accumulate significantly in the serum of RA patients. Here, we present the first investigation of the effects of AOPPs on RA-FLSs and the signalling pathway involved in AOPP-induced inflammatory responses and invasive behaviour. METHODS: We used different concentrations of AOPPs (50 to 200 µg/ml) to treat RA-FLSs. Cell migration and invasion and the expression levels of tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), matrix metalloproteinase-3 (MMP-3), and MMP-13 were investigated. Western blot and immunofluorescence were used to analyze nuclear factor-κB (NF-κB) activation. RESULTS: AOPPs promoted RA-FLS migration and invasion in vitro and significantly induced the messenger RNA (mRNA) and protein expression of TNF-α, IL-6, MMP-3, and MMP-13 in dose- and time-dependent manners. Moreover, AOPPs markedly activated the phosphorylation of nuclear factor-κB (NF-κB) p65 protein, which triggered inhibitory kappa B-alpha (IκBα) degradation, NF-κB p65 protein phosphorylation, and NF-κB p65 translocation into the nucleus. Furthermore, treatment with a neutralizing antibody specific to receptor for advanced glycation end products (RAGE) significantly suppressed aggressive behaviour and inflammation, decreased TNF-α, IL-6, MMP-3, and MMP-13 expression, and blocked AOPP-induced NF-κB pathway activation. CONCLUSION: The results indicate that AOPPs can enhance aggressive behaviour and the inflammatory response in RA-FLSs via the RAGE-NF-κB pathway. These results present AOPPs as a new class of potentially important mediators of progressive disease in RA patients. Cite this article: Bone Joint Res 2021;10(4):259-268.

Circular RNA in tumor metastasis.

Circular RNAs (circRNAs) are a type of endogenous non-coding RNA that were discovered to regulate gene expression through multiple pathways. Metastasis remains one of the biggest obstacles in cancer treatment. In this review, we focus on circRNAs involved in cancer tumorigenesis and metastasis. We present recently identified tumor-related circRNAs and discuss their functioning in tumor progression and metastasis. These circRNAs are categorized into different functional mechanisms, including microRNA (miRNA) sponging, protein binding, regulation of host genes, translation of circRNAs, and exosomal circRNAs. Additionally, the indirect functions of circRNAs that regulate epithelial-mesenchymal transition and autophagy are also discussed.

Serum KL-6, CA19-9, CA125 and CEA are Diagnostic Biomarkers for Rheumatoid Arthritis-Associated Interstitial Lung Disease in the Chinese Population.

INTRODUCTION: This study aimed to evaluate the role of tumor marker carbohydrate antigen (CA) 125 (CA125), CA19-9, carcinoembryonic antigen (CEA) and Krebs von den Lungen-6 (KL-6) in the diagnosis and determination of the severity of interstitial lung disease (ILD) in rheumatoid arthritis (RA) patients. METHODS: A retrospective analysis was performed. Fifty RA patients (24 patients with ILD and 26 patients without ILD), 10 healthy subjects and 14 patients with other connective tissue disease-associated interstitial lung disease were included. Serum levels of KL-6 and tumor markers CA19-9, CA125 and CEA were measured. Chest HRCT of patients with ILD was scored quantitatively according to the degree of fibrosis. Data on the C-reactive protein, erythrocyte sedimentation rate, rheumatoid factors and anti-cyclic peptide containing citrulline (anti-CCP) were also collected. RESULTS: Serum levels of KL-6, CA19-9, CA125 and CEA in the RA-ILD group were significantly higher than those in the RA-no-ILD group. The serum KL-6 level was positively correlated with the HRCT fibrosis score (r = 0.63, p = 0.002). The logistic regression analysis showed that CA19-9 and smoking were associated with RA-ILD [OR = 1.118, 95% CI = (1.038, 1.204), p = 0.003 for CA19-9, OR = 14.969, 95% CI = (1.750, 128.043), p = 0.013 for smoking]. CONCLUSIONS: KL-6 level and tumor markers were elevated in RA-ILD, and strongly associated with the severity of ILD, supporting their value as pathogenically relevant biomarkers, which can contribute to noninvasive detection of this extra-articular disease complication.

Interstitial lung disease (ILD) is a common pulmonary manifestation of RA associated with high morbidity and mortality. Our retrospective study was performed to investigate the clinical utility of tumor marker carbohydrate antigen (CA) 125 (CA125), CA19-9, carcinoembryonic antigen (CEA) and Krebs von den Lungen-6 (KL-6) in the diagnosis and determining the severity of RA-ILD. Fifty RA patients (24 patients with ILD and 26 patients without ILD), 10 healthy subjects and 14 patients with other connective tissue disease-associated interstitial lung disease (CTD-ILD) were included. The results showed KL-6 level and tumor markers were elevated in RA-ILD, and strongly associated with the severity of ILD, which meant KL-6 and tumor markers might be useful pathogenically relevant biomarkers and could be predictors for the diagnosis and determination of severity of ILD in RA.

Dysregulated ICOS+ proinflammatory and suppressive regulatory T cells in patients with rheumatoid arthritis.

Regulatory T cells (Tregs) serve an important role in the pathogenesis of rheumatoid arthritis (RA) by regulating autoimmunity and inflammation. Humans and mice contain inducible T-cell costimulator-positive (ICOS+) Tregs, although their role in RA is unclear. A total of 33 patients with RA and 17 normal control (NC) subjects were examined. The proportion of ICOS+ Tregs in the peripheral blood and intracellular cytokine levels in these cells were assessed using flow cytometry. The percentage of ICOS+ Tregs increased in the cohort of patients with RA compared with the NCs. Such increases were much larger in patients with inactive RA compared with patients with active RA. Additionally, ICOS+ Tregs expressed multiple suppressive cytokines, including interleukin (IL)-10, transforming growth factor-ß and IL-35, but expressed low levels of IL-17. Importantly, the expression of suppressive cytokines in ICOS+ Tregs from patients with active RA decreased, but IL-17 expression noticeably increased compared with patients with inactive RA. The present findings suggested that ICOS+ Tregs may perform inflammatory and inhibitory functions, and abnormal ICOS+ Tregs numbers and functions may contribute to the pathogenesis of RA.

Inhibition of Cyclic GMP-AMP Synthase Using a Novel Antimalarial Drug Derivative in Trex1-Deficient Mice.

OBJECTIVE: Type I interferon (IFN) is strongly implicated in the pathogenesis of systemic lupus erythematosus (SLE) as well as rare monogenic interferonopathies such as Aicardi-Goutières syndrome (AGS), a disease attributed to mutations in the DNA exonuclease TREX1. The DNA-activated type I IFN pathway cyclic GMP-AMP (cGAMP) synthase (cGAS) is linked to subsets of AGS and lupus. This study was undertaken to identify inhibitors of the DNA-cGAS interaction, and to test the lead candidate drug, X6, in a mouse model of AGS. METHODS: Trex1-/- mice were treated orally from birth with either X6 or hydroxychloroquine (HCQ) for 8 weeks. Expression of IFN-stimulated genes (ISGs) was quantified by quantitative polymerase chain reaction. Multiple reaction monitoring by ultra-performance liquid chromatography coupled with tandem mass spectrometry was used to quantify the production of cGAMP and X6 drug concentrations in the serum and heart tissue of Trex1-/- mice. RESULTS: On the basis of the efficacy-to-toxicity ratio established in vitro, drug X6 was selected as the lead candidate for treatment of Trex1-/- mice. X6 was significantly more effective than HCQ in attenuating ISG expression in mouse spleens (P < 0.01 for Isg15 and Isg20) and hearts (P < 0.05 for Isg15, Mx1, and Ifnb, and P < 0.01 for Cxcl10), and in reducing the production of cGAMP in mouse heart tissue (P < 0.05), thus demonstrating target engagement by the X6 compound. Of note, X6 was also more effective than HCQ in reducing ISG expression in vitro (P < 0.05 for IFI27 and MX1, and P < 0.01 for IFI44L and PKR) in human peripheral blood mononuclear cells from patients with SLE. CONCLUSION: This study demonstrates that X6 is superior to HCQ for the treatment of an experimental autoimmune myocarditis mediated in vivo by the cGAS/stimulator of IFN genes (cGAS/STING) pathway. The findings suggest that drug X6 could be developed as a novel treatment for AGS and/or lupus to inhibit activation of the cGAS/STING pathway.

Comprehensive circular RNA profiles in plasma reveals that circular RNAs can be used as novel biomarkers for systemic lupus erythematosus.

Circular RNAs (circRNAs), a novel class of widespread endogenous noncoding RNAs, have been involved in the development of various diseases, including atherosclerosis, Alzheimer's disease and several types of cancers, but there is little knowledge about their associations with systemic lupus erythematosus (SLE). This study is aimed to identify the expression profiles of circRNAs in 6 paired SLE and normal participants plasma samples by using a circRNA microarray. The microarray analysis showed that 207 circRNAs were differentially expressed between these two groups, including 113 upregulated and 94 downregulated circRNAs. Then, we selected 8 circRNAs as candidate biomarkers from the microarray analysis and further verified them in another group of subjects consisting of 24 SLE patients and 24 normal controls using quantitative real-time polymerase chain reaction assays (qRT-PCR). Finally, we confirmed four circRNAs that were consistent with the microarray results. In addition, bioinformatics was employed to predict the interaction between validated circRNAs and potential miRNA targets. Taken together, we firstly illustrate the comprehensive expression profiles of circRNAs in SLE patients plasma and lay the foundations to develop circRNAs as novel non-invasive biomarkers for SLE disease in the future.

MicroRNA­198 contributes to lupus nephritis progression by inhibition of phosphatase and tensin homology deleted on chromosome ten expression.

A number of short noncoding microRNAs (miRs) have been demonstrated to be highly expressed in many kidney diseases such as renal cancer and lupus nephritis (LN); however, these results have not been extensively investigated. The aim of the present study was to investigate the expression and function of miR­198 in LN based on the previous studies. miR­198 expression level in systemic lupus erythematosus (SLE) patients was determined to determine its clinicopathological significance and effect on glomerular cell proliferation. It was demonstrated that higher expression of miR­198 was observed in patients with SLE, and was correlated with disease activity. Bioinformatics prediction and luciferase assays were used to demonstrate that miR­198 could directly bind to the phosphatase and tensin homology deleted on chromosome ten (PTEN) 3'­untranslated region. Furthermore, miR­198 overexpression reduced PTEN expression levels, while miR­198 silencing increased its expression at both the mRNA and protein level. Furthermore, there was a negative association between miR­198 and PTEN in the patients with active SLE. Thus, miR­198 may promote proliferation and contribute to SLE progression by targeting PTEN.

[Behcet's disease complicated by malignant lymphoma: a case report and literature review].

Malignant lymphoma complicated by Behcet's disease (BD) is a rare clinical entity. We report a case of BD complicated by malignant lymphoma in a 26-year-old male patient. The patient was diagnosed to have terminal ileum extranodal NK/T-cell lymphoma (nasal type) during treatment for BD with cyclophosphamide (CTX), immunoregulants and biological agents. This is the first case reported in China and the second case globally. The pathogenesis of BD complicated by malignant lymphoma remains unclear. We reviewed the relevant literatures to summarize the clinical characteristics of BD complicated by extranodal NK/T-cell lymphoma (nasal type) and discuss the possible pathogenesis in light of immunology, EB virus infection and medications.