The role and mechanism of myeloperoxidase in dermatomyositis.

OBJECTIVE: Dermatomyositis (DM) is the best known subtype of idiopathic inflammatory myopathies. The hallmarks of DM muscle pathology including microangiopathy, inflammatory infiltration, and perifascicular atrophy. Recent findings have revealed pathogenetic effects of myeloperoxidase (MPO) by causing oxidative damage and regulating abnormal immunity in multiple disease conditions. In this study, we aimed to explore the role of MPO in the pathogenesis of DM. METHODS: The peripheral blood mononuclear cell (PBMC) mRNA expression and DNA methylation of MPO were verified using real-time qPCR and bisulfite pyrosequencing, respectively. Plasma MPO levels were measured with enzyme-linked immunosorbent assay, and their relationships with clinical characteristics were analyzed. The expression and distribution of MPO in muscle were tested by immunofluorescence. Purified human native MPO protein was used to stimulate human dermal microvascular endothelial cells (HDMECs) and skeletal muscle myotubes. The cell viability, tube forming capacity, permeability, adhesion molecule expressions in HDMECs, and atrophy and programmed cell death pathways in myotubes were then observed. RESULTS: MPO gene methylation was decreased, while mRNA expression and plasma levels were increased in DM. Plasma MPO of DM patients was positively correlated with serum creatine kinase (CK). MPO mainly distributed around endomysia capillaries and perifascicular atrophy in DM muscle biopsies, and was co-localized with CD4+, CD8+ T cells and CD19+ B cells. MPO not only could influence the cell viability, tube forming capacity, permeability and expression of adhesion molecules (including ICAM 1, VCAM 1 and E-selectin) of HDMECs, but also could cause atrophy of myotubes. CONCLUSIONS: Our study disclosed, for the first time, that MPO plays an important role in promoting inflammatory infiltration and inducing muscle damage in DM patients. MPO may be a potential biomarker for DM muscle involvement and MPO targeted drugs may be promising in DM treatment.

Integrated comparison of the mRNAome in cartilage, synovium, and macrophages in osteoarthritis.

The precise molecular mechanisms associated with osteoarthritis (OA), the most common musculoskeletal disorder, are poorly understood. There are currently no effective treatments to prevent the initiation and progression of the disease. In recent years, the development of mRNAome has made it possible to identify new mechanisms and therapeutic targets. However, the differentially expressed genes screened by different microarrays are not completely the same. In order to avoid this shortcoming, we integrate the different genes from different tissues and data sets, and select the commonly expressed genes for further studies.

The predictive value of neutrophil-to-lymphocyte ratio for overall survival and pathological complete response in breast cancer patients receiving neoadjuvant chemotherapy.

Purpose: Previous studies have reported that neutrophil-to-lymphocyte ratio (NLR) at pre-treatment was predictive for overall survival (OS) and pathologic complete response (pCR) in breast cancer (BC) patients receiving neoadjuvant chemotherapy (NAC). This study aims to explore the predictive role of both pre- and post-NLR for OS as well as longitudinal NLR kinetics towards pCR in BC patients undergoing NAC. Methods: We retrospectively included 501 BC patients who received NAC from 2009 to 2018. NLR at pre-, mid (every two cycles of NAC)-, and post-treatment were collected. Overall, 421 patients were included in the survival analysis. These patients were randomly divided into a training cohort (n = 224) and a validation cohort (n = 197). A multivariable Cox model was built using all significant factors in the multivariable analysis from the training cohort. The performance of the model was verified in the validation cohort by the concordance index (C-index). Longitudinal analysis for pCR prediction of NLR was performed using a mixed-effects regression model among 176 patients who finished eight cycles of NAC. Results: The median follow-up time was 43.2 months for 421 patients. In the training cohort, multivariable analysis revealed that ER status, clinical node stage, pCR, pre-NLR, and post-NLR (all p < 0.05) were independent predictors of OS. The OS nomogram was established based on these parameters. The C-indexes of the nomogram were 0.764 and 0.605 in the training and validation cohorts, respectively. In the longitudinal analysis, patients who failed to achieve pCR experienced an augment of NLR during NAC while NLR remained stable among patients with pCR. Pre-NLR tended to be significantly associated with OS in patients of HER2 overexpressing and TNBC subtypes (all p < 0.05), but not in Luminal A and Luminal B subtypes. Conclusions: This study demonstrated the prognostic value of both pre-NLR and post-NLR on clinical outcomes in BC patients receiving NAC. A novel nomogram was established to predict OS. Non-pCR patients developed increased NLRs during NAC. Routine assessment of NLR may be a simple and affordable tool to predict prognosis for BC patients receiving NAC.

Simple metabolic markers associated with tophaceous gout.

INTRODUCTION: The relationship between tophaceous gout and metabolic markers is not well understood. The aim of this study was to compare the correlations between different metabolic markers and tophi and evaluate their potential predictive values for tophus. METHOD: We analysed the data of gout patients in Beijing Jishuitan Hospital from 2013 to 2020. Ten laboratory indicators (UA, eGFR, underexcretion, GLU, TRIG, HDL-C, ALT, TBIL, γ-GT and UPH) were included to evaluate the relationship between tophaceous gout and metabolic markers. RESULTS: Tophi was present in 14.7% (119/808) of gout patients. UA, eGFR, ALT and γ-GT were independently related to the development of tophi; UA and γ-GT were positively correlated. The γ-GT/ALT ratio and UA/eGFR ratio showed a positive correlation with tophi, with (rho, P) of (0.305, < 0.001) and (0.195, < 0.001), respectively. The γ-GT/ALT ratio showed the best classificatory performance (AUC = 0.749, P < 0.001) for tophi among the four positive correlation indicators. With increasing integer γ-GT/ALT ratio, the incidence of tophi (4.9%, 9.7%, 22.3% and 38.4%, P < 0.001), chronic kidney disease (2.5%, 5.2%, 12.3% and 19.2%, P < 0.001) and hyperuricemia over 10 years (6.6%, 10.7%, 18.5% and 26.4%, P < 0.001) showed a progressive increase. The γ-GT/ALT ratio was positively correlated with the number of tophi and duration of hyperuricemia, negatively correlated with eGFR. CONCLUSIONS: UA, eGFR, γ-GT and ALT were independently associated with tophi. The γ-GT/ALT ratio may be used as a predictor or monitor of tophi.

Impact of effective dose to immune cells (EDIC) on lymphocyte nadir and survival in limited-stage SCLC.

BACKGROUND: Effective dose to immune cell (EDIC), an estimated radiation dose to the circulating lymphocytes, is of significance for overall survival (OS) in non-small cell lung cancer. This study aimed to validate the EDIC's OS effect on limited-stage small cell lung cancer (LS-SCLC). METHOD AND MATERIALS: This study included LS-SCLC patients received definitive chemo-radiation in one single center from 2012 to 2017. All patients had multiple complete-blood-count tests including lymphocyte count at pre-, during- and end- radiotherapy. EDIC, computed according to doses of the lung, heart, and the total body, was assessed for its correlation with lymphocyte nadir, OS and progression free survival (PFS). RESULTS: Of 503 eligible patients, the mean EDIC was 7.34 Gy. The mean lymphocyte nadir was 0.48 × 109 cells/L, significantly lower than 1.65 × 109 cells/L at pre-radiotherapy (p < 0.001). EDIC was significantly correlated with lymphocyte nadir under both univariate (p < 0.001) and multivariable linear regression (p < 0.001). Multivariable analysis showed EDIC (HR = 0.1072, p = 0.005) and lymphocyte nadir (HR = 0.345, p = 0.003) were both significant for OS. EDIC was also significant for PFS (HR = 1.046, p = 0.026). The C-indexes of OS prediction were 0.593, 0.617, 0.676, and 0.684, for lymphocyte nadir alone, EDIC alone, combined lymphocyte nadir model, and combined EDIC model, respectively. CONCLUSIONS: This study demonstrated that EDIC is an independent predictor for lymphocyte nadir, PFS and OS. EDIC may serve as a predictor for lymphocyte nadir and a surrogate marker for OS in LS-SCLC. More attention should be paid to EDIC to decease the lymphocyte toxicity and improve survival.

PKM2-dependent glycolysis promotes skeletal muscle cell pyroptosis by activating the NLRP3 inflammasome in dermatomyositis/polymyositis.

OBJECTIVES: Muscle cell necrosis is the most common pathological manifestation of idiopathic inflammatory myopathies. Evidence suggests that glycolysis might participate in it. However, the mechanism is unclear. This study aimed to determine the role of glycolysis in the muscle damage that occurs in DM/PM. METHODS: Mass spectrometry was performed on muscle lesions from DM/PM and control subjects. The expression levels of pyruvate kinase isozyme M2 (PKM2), the nucleotide-binding and oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3) inflammasome and pyroptosis-related genes in muscle tissues or plasma were determined by real-time PCR, western blot analysis, IF and ELISA. In addition, IFNγ was used to stimulate myotubes, and the relationships among PMK2 expression, NLRP3 inflammasome activation and pyroptosis were investigated. RESULTS: Mass spectrometry and bioinformatics analysis suggested that multiple glycolysis processes, the NLRP3 inflammasome and programmed cell death pathway-related proteins were dysregulated in the muscle tissues of DM/PM. PKM2 and the NLRP3 inflammasome were upregulated and positively correlated in the muscle fibres of DM/PM. Moreover, the pyroptosis-related proteins were increased in muscle tissues of DM/PM and were further increased in PM. The levels of PKM2 in muscle tissues and IL-1ß in plasma were high in patients with anti-signal recognition particle autoantibody expression. The pharmacological inhibition of PKM2 in IFNγ-stimulated myotubes attenuated NLRP3 inflammasome activation and subsequently inhibited pyroptosis. CONCLUSION: Our study revealed upregulated glycolysis in the lesioned muscle tissues of DM/PM, which activated the NLRP3 inflammasome and leaded to pyroptosis in muscle cells. The levels of PKM2 and IL-1ß were high in patients with anti-signal recognition particle autoantibody expression. These proteins might be used as new biomarkers for muscle damage.

A fatal multiple-lesion, inflammatory, pseudotumor in the lung: a rare case report.

An inflammatory pseudotumor is considered a benign form of lesion marked by a proliferation of myofibroblasts with different degrees of inflammatory infiltrates. Pulmonary inflammatory pseudotumors (PIPs) are extremely rare in middle-aged adults. Normally, a PIP has a single lesion, and can be controlled constantly by surgery and drugs. In this paper, we report a case study of a 51-year-old male patient who presented with multiple inflammatory pseudotumors in lungs, thoracic spine, ribs, left humerusl, derived from PIPs throughout his body, which indicated a long disease term and significant recrudescence. After 6 surgeries (a wedge resection of the right lower lobe, a removal of three thoracic vertebral lesions, a removal of left humeral tumor lesion, a right lower lobe resection, local cryoablation of right lung, debridement of left upper-arm osteomyelitis and soft tissue infection), radiotherapy for lesions of left humerus destruction at a total dose of 20 Gy/10 F, and systematic treatments (30 mg prednisone acetate daily for 6 weeks, 50 mg compound cyclophosphamide tablets for 2 weeks; antibiotics, blood transfusions, nutritional support), his symptoms improved but reoccurred. The patient ultimately died of septic shock. Our case report highlights that the progression of a PIP to a malignant form requires further research. A multiple-lesion PIP that does not respond to systemic treatment can be highly dangerous.

Pre-radiotherapy lymphocyte count and platelet-to-lymphocyte ratio may improve survival prediction beyond clinical factors in limited stage small cell lung cancer: model development and validation.

BACKGROUND: Few small sample size studies have reported lymphocyte count was prognostic for survival in small-cell lung cancer (SCLC). This study aimed to validate this finding, to build prediction model for overall survival (OS) and to study whether novel models that combine lymphocyte-related variables can predict OS more accurately than a conventional model using clinical factors alone in a large cohort of limited-stage SCLC patients. METHODS: This study enrolled 544 limited-stage SCLC patients receiving definitive chemo-radiation with pre-radiotherapy lymphocyte-related variables including absolute lymphocyte count (ALC), platelet-to-lymphocyte ratio (P/L ratio), neutrophil-to-lymphocyte ratio (N/L ratio), and lymphocyte-to-monocyte ratio (L/M ratio). The primary endpoint was OS. These patients were randomly divided into a training dataset (n=274) and a validation dataset (n=270). Multivariate survival models were built in the training dataset, and the performance of these models were further tested in the validation dataset using the concordance index (C-index). RESULTS: The median follow-up time was 36 months for all patients. In the training dataset, univariate analysis showed that ALC (P=0.020) and P/L ratio (P=0.023) were significantly correlated with OS, while L/M ratio (P=0.091) and N/L ratio (P=0.436) were not. Multivariate modeling demonstrated the significance of ALC (P=0.063) and P/L ratio (P=0.003), and the improvement for OS prediction in combined models with the addition of ALC (C-index =0.693) or P/L ratio (C-index =0.688) over the conventional model (C-index =0.679). The validation dataset analysis confirmed a modest improvement of C-index with the addition of ALC or P/L ratio. All these models showed reasonable discriminations and calibrations. CONCLUSIONS: This study validated the significant value of pre-radiotherapy ALC and P/L ratio on OS in limited-stage SCLC. The combined model with ALC or P/L ratio showed additional OS prediction values than the conventional model with clinical factors alone.

Increased Serum Matrix Metalloproteinase-9 Levels are Associated with Anti-Jo1 but not Anti-MDA5 in Myositis Patients.

Matrix metalloproteinases 9 (MMP9) is a member of the zinc-ion-dependent proteinases family and plays a pathogenic role in chronic inflammatory autoimmune diseases. However, its roles in the pathogenesis of myositis have not been elucidated. In this study, we aimed to determine the gene expression and serum level of MMP9 and their relationship with clinical features and serological parameters in myositis. Our results showed that MMP9 mRNA in peripheral blood mononuclear cells (PBMC) was upregulated in myositis patients compared to that in healthy controls. Myositis patients positive for anti-Jo1 antibodies exhibited significantly higher serum MMP9 than anti-MDA5 positive or antibody-negative patients and healthy controls. However, the presence of interstitial lung disease (ILD) did not affect MMP9 levels. We further identified that anti-Jo1-positive myositis patients showed higher numbers of white blood cells (WBC), lymphocytes and neutrophils; increased levels of creatine kinase (CK), lactate dehydrogenase (LDH), and C-reactive protein (CRP); and higher erythrocyte sedimentation rate (ESR) than anti-MDA5 positive patients. In addition, serum MMP-9 levels were positively correlated with WBCs, neutrophils, CK, CRP, ESR, and LDH in myositis patients. In vitro experiments showed that purified serum IgG from Jo-1-positive patients could stimulate PBMCs to release more MMP9 than the IgG from MDA-5-positive sera. These results indicated that increased MMP9 in anti-Jo1-positive myositis patients was associated with the extent of muscle involvement, but not pulmonary damage. The distinct pattern of serum MMP9 perhaps clarifies the differences in pathophysiology between anti-Jo1 and anti-MDA5 in patients with myositis.

Global analysis of protein expression in muscle tissues of dermatomyositis/polymyosisits patients demonstrated an association between dysferlin and human leucocyte antigen A.

OBJECTIVES: DM and PM are characterized by myofibre damage with inflammatory cell infiltration due to the strong expressions of MHC class I HLA-A and monocyte chemoattractant protein-1 (MCP-1). Dysferlin (DYSF) is a transmembrane glycoprotein that anchors in the sarcolemma of myofibres. DYSF mutation is closely associated with inherited myopathies. This study aimed to determine the role of DYSF in the development of DM/PM. METHODS: Mass spectrometry was performed in muscle tissues from DM/PM patients and controls. The DYSF levels in muscle tissue, peripheral blood cells and serum were detected by Western blotting, IF, flow cytometry or ELISA. Double IF and co-immunoprecipitation were used to investigate the relationship between DYSF and HLA-A. RESULTS: Mass spectrometry and bioinformatics analysis findings suggested the dysregulated proteins in DM/PM patients participated in common biological processes and pathways, such as the generation of precursor metabolites and energy. DYSF was upregulated in the muscle tissue and serum of DM/PM patients. DYSF was mainly expressed in myofibres and co-localized with HLA-A and MCP-1. DYSF and HLA-A expressions were elevated in myocytes and endothelial cells after being stimulated by patient serum and IFN-ß. However, no direct interactions were found between DYSF and HLA-A by co-immunoprecipitation. CONCLUSION: Our study revealed the dysregulated proteins involved in common and specific biological processes in DM/PM patient samples. DYSF is upregulated and exhibits a potential role along with that of HLA-A and MCP-1 in inflammatory cell infiltration and muscle damage during the development of DM/PM.

Integrated comparison of the miRNAome and mRNAome in muscles of dermatomyositis and polymyositis reveals common and specific miRNA-mRNAs.

AIM: Dermatomyositis (DM) and polymyositis (PM) are refractory systemic autoimmune diseases with unknown pathogenesis. miRNAs is an important epigenetic mechanism to regulate gene expression. METHODS: We performed whole miRNAs analysis, transcription analysis and the association between miRNAome and mRNAome. RESULTS: For transcription and miRNAs analysis, there were common and specific mRNAs and miRNAs in the muscles of DM and PM. Among them, the expression levels of miR-196a-5p and CPM were negatively correlated in PM, miR-193b-3p and NECAP2 were negatively correlated in DM and PM. Protein carboxypeptidase M (CPM) plays roles in the degradation of extracellular proteins and in the migration and invasion of cancer cells, and protein NECAP2 plays roles in adaptor protein AP-1-mediated fast recycling from early endosomes. The functions of them in the pathogenesis of DM/PM need further studies. CONCLUSION: Our study identified and confirmed differentially miRNAs and mRNAs in DM and PM. Our observations have laid the groundwork for further diagnostic and mechanistic studies of DM and PM.

The roles of neutrophil serine proteinases in idiopathic inflammatory myopathies.

BACKGROUND: Dermatomyositis and polymyositis are the best known idiopathic inflammatory myopathies (IIMs). Classic histopathologic findings include the infiltration of inflammatory cells into muscle tissues. Neutrophil serine proteinases (NSPs) are granule-associated enzymes and play roles in inflammatory cell migration by increasing the permeability of vascular endothelial cells. In this study, we aimed to find the roles of NSPs in pathogenesis of IIMs. METHODS: RNA and DNA were isolated to measure the relative expression of NSPs and their methylation levels. The expression of NSPs in serum and muscle tissues was tested by enzyme-linked immunosorbent assay, immunohistochemistry, and immunofluorescence, respectively. Serum from patients was used to culture the human dermal microvascular endothelial cells (HDMECs), and then we observed the influence of serum on expression of VE-cadherin, endothelial cell tube formation, and transendothelial migration of peripheral blood mononuclear cells (PBMCs). RESULTS: We found that the expression of NSPs was increased in PBMCs, serum, and muscle tissues of IIM patients; these NSPs were hypomethylated in the PBMCs of patients. Serum NSPs were positively correlated with clinical indicators of IIM patients, including lactic dehydrogenase, erythrocyte sedimentation rate, C-reactive protein, immunoglobulin G, immunoglobulin M, and immunoglobulin A. Patients with anti-Jo-1, with anti-Ro-52, or without interstitial lung disease had lower levels of proteinase 3. Serum NSPs degraded the VE-cadherin of HDMECs, and serum NSP application increased the permeability of HDMECs. CONCLUSIONS: Our studies indicate, for the first time, that NSPs play an important role in muscle inflammatory cell infiltration by increasing the permeability of vascular endothelial cells in IIM patients.

Effect of nisin on microbiome-brain-gut axis neurochemicals by Escherichia coli-induced diarrhea in mice.

The effects of nisin on the neurochemicals, Aquaporin-3 (AQP-3) and intestinal microorganisms in the brain-gut axis of mice were analyzed by using enzyme linked immune sorbent assay (ELISA) and high throughput sequencing in this investigation, to further revealed the relationship between intestinal flora abundance in mice and neurochemicals in the brain-gut axis. Using HE staining found damage of structure of small intestine villi in the model group (Escherichia coli O1, E. coli O1). Compared with normal control and ciprofloxacin groups, using ELISA showed that nisin increased the highest norepinephrine (NE) expression in the brain, expression of 5-hydroxytryptamine (5-HT) and dopamine (DA) in the duodenum, and increased the expression of AQP-3 in jejunum. Using high-throughput sequencing showed the highest diversity of cecal microflora in nisin group (ACE-index = 1417.25, Chao1-index = 1378.45), but the cecal microflora in the negative control group (ACE-index = 969.54, Chao1-index = 340.29) exhibited the lowest species diversity. Our data indicated that nisin regulates neurochemicals, AQP-3 and cecal microflora imbalance in mice.

Cathepsin G and Its Role in Inflammation and Autoimmune Diseases.

Cathepsin G belongs to the neutrophil serine proteases family, known for its function in killing pathogens. Studies over the past several years indicate that cathepsin G has important effects on inflammation and immune reaction, and may be a key factor in the pathogenesis of some autoimmune diseases. In this article, we discuss the roles of cathepsin G in inflammation, immune reaction, and autoimmune diseases. To our knowledge, this is the first study providing important information about cathepsin G in the pathogenesis of autoimmune diseases and suggesting that cathepsin G may be a new biomarker or treatment target.

Using multi-omics methods to understand dermatomyositis/polymyositis.

Idiopathic inflammatory myopathies (IIM) are a group of rare and heterogeneous autoimmune diseases, and the most common subtypes are dermatomyositis (DM) and polymyositis (PM). Despite extensive efforts, the underlying mechanism of IIM remains unclear. Recent efforts to understand the pathogenesis of IIM have included genomics, epigenetics, transcriptomics, proteomics and autoantibody studies. This review focuses on recent studies in DM/PM research based on multi-omics. This integrated analysis of multi-omics profiling will provide useful insights into DM/PM pathogenesis and recommendations for therapeutic targets and biomarkers development.

The role and mechanism of cathepsin G in dermatomyositis.

Dermatomyositis (DM) is an idiopathic inflammatory myopathy characterized by CD4+ T cells and B cells infiltration in perivascular and muscle tissue. Although the infiltration of inflammatory cells plays a key role in muscle damage, the exact mechanism is not clear. Cathepsin G (CTSG) is a member of the serine proteases family and can increase the permeability of vascular endothelial cells and the chemotaxis of inflammatory cells. In this study, we found that the expression of CTSG was increased in peripheral blood mononuclear cells and muscle tissues of DM patients. The activity of CTSG was significantly increased in DM patients and correlated with disease activity. Serum CTSG induced the expression of protease activated receptor 2 (PAR2) and altered the cytoskeleton of human dermal microvascular endothelial cells. Our studies indicate, for the first time, that CTSG may play an important role in muscle inflammatory cells infiltration by increasing the permeability of vascular endothelial cells.

MicroRNA-202-3p regulates scleroderma fibrosis by targeting matrix metalloproteinase 1.

The leading cause of death in systemic sclerosis (SSc) is the uncontrolled fibrosis in multiple organs. The exact mechanism of fibrosis is not fully clear. Our previous studies using miRNA array analysis indicated that miR-202-3p was increased in SSc lesion skin tissues. Bioinformatics analysis suggested matrix metallopeptidase (MMP) 1 is the target gene of miR-202-3p. Here we confirmed that miR-202-3p was upregulated, and the mRNA and protein expression of MMP1 were significantly decreased in SSc skin tissues and primary fibroblast compared with normal skin. MMP1 expression was inversely correlated with the expression of miR-202-3p. Overexpression of miR-202-3p markedly increased collagen disposition in skin primary fibroblasts, while inhibitor of miR-202-3p decreased it. Furthermore, we demonstrated that MMP1 was a target of miR-202-3p detected by luciferase reporter assay, and played an essential role as a mediator of the biological effects of miR-202-3p in SSc fibrosis. Taken together, these findings suggest that miR-202-3p may function as a novel pro-fibrotic miRNA in SSc by inhibition the expression of MMP1.