The IgG2 Isotype of Anti–Transcription Intermediary Factor 1γ Autoantibodies Is a Biomarker of Cancer and Mortality in Adult Dermatomyositis

TIF1-γ Positive Dermatomyositis with Spontaneous Muscular Hematoma in the Context of Ovarian Cancer: A Novel Survival Case Report

Background

Dermatomyositis (DM) represents a group of inflammatory myopathies, with TIF1-γ positive DM strongly associated with malignancies. Spontaneous muscular hematoma in DM patients is exceedingly rare and often prognosticates a severe clinical outcome, especially in the context of concurrent malignancy.

Case Presentation

We describe a novel survival case of a patient with TIF1-γ positive DM and an underlying ovarian tumor who developed a spontaneous muscular hematoma. Despite the traditionally poor prognosis of these conditions, the patient survived through a comprehensive treatment regimen. This included targeted chemotherapy for ovarian cancer (Carboplatin and Paclitaxel), alongside corticosteroids, immunoglobulins, and immunosuppressants for DM, as well as component blood transfusions, coagulation correction therapy to control hematoma, and integrated management: nutritional support, lung function exercise, volume management.

Results

The integrated treatment strategy stabilized the patient's condition and resolved the hematoma, a significant achievement given the usual high mortality rate of such complications.

Conclusion

This case underscores the importance of a multidisciplinary approach in the early diagnosis and treatment of TIF1-γ positive DM with complex comorbidities, including spontaneous muscular hematoma and ovarian cancer. It highlights the potential for favorable outcomes with aggressive and coordinated treatment strategies.

Paraneoplastic myopathies

This chapter reviews the association between cancer and the idiopathic inflammatory myopathies (IIM), which includes dermatomyositis (DM), antisynthetase syndrome (ASyS), immune-mediated necrotizing myopathy (IMNM), and inclusion body myositis (IBM). Accumulating evidence shows that the risk of a coexisting malignancy is high in patients with DM, especially among those with anti-Tif1γ autoantibodies. Patients with IMNM and no defined autoantibodies also have an increased risk of malignancy. Recent evidence demonstrates that many IBM patients have increased numbers of circulating CD57+ CD8+ T cells, consistent with a diagnosis of large granular lymphocytic leukemia. In contrast, IMNM patients with anti-SRP or anti-HMGCR autoantibodies as well as patients with ASyS syndrome do not have a definitively increased risk of cancer. Patients who have a cancer treated with one of the immune checkpoint inhibitors can develop myositis (ICI-myositis), sometimes along with myasthenia gravis and/or myocarditis.

Clinical features of dermatomyositis patients with anti-TIF1 antibodies: A case based comprehensive review

BACKGROUND AND OBJECTIVES

Dermatomyositis is chronic autoimmune disease primarily affecting skin and muscles. Antibodies are key players of pathogenesis and are in strong correlation with distinct clinical phenotypes. We present a case and a comprehensive review of the literature on dermatomyositis patients with Anti TIF1 antibodies.

METHODS

PubMed and Web of Science databases were reviewed. 166 articles were identified; 95 of them were evaluated; 79 of them included to the study. 45 of the included articles were case reports 9 were case series and 25 were research articles. In total 1065 patients were identified but number of patients with available information for different clinical features varied.

RESULTS

69.6% of the patients with Anti TIF1-γ were female. Prevalence of malignancy was 42.6% among patients with Anti TIF1-γ. Muscle weakness (83%), Gottron sign (82.2%), heliotrope rash (73.7%), nailfold capillary changes (67.7%), dysphagia (38.4%), and joint involvement (31.1%) were the most common clinical features seen in patients with Anti TIF1-γ. Interstitial lung disease (ILD) was reported among 8.7% of patients with Anti TIF1-γ. Advanced age, male gender, dysphagia, and V-neck rash were significant risk factors for malignancy, whereas juvenile age, ILD, TIF1-β antibodies and joint involvement were associated with a decreased risk for malignancy. Advanced age, malignancy, dysphagia, and muscle involvement were associated with an increased risk for mortality.

CONCLUSIONS

Patients with advanced age, male gender, dysphagia, and V-neck rash require strict cancer screening. Patients with advanced age, malignancy, dysphagia, and muscle involvement have poor prognosis and should receive aggressive treatment.

Evaluation and validation of the prognostic value of anti-MDA5 IgG subclasses in dermatomyositis-associated interstitial lung disease

OBJECTIVE

To investigate the association between the anti-melanoma differentiation associated gene 5 (MDA5) IgG subclasses and prognosis of patients with dermatomyositis (DM)-associated interstitial lung disease (ILD).

METHODS

This retrospective study included 122 anti-MDA5 positive DM-ILD patients admitted from October 2017 to October 2020 as training cohort, and additional 68 patients from August 2014 to September 2017 as validation cohort. The levels of anti-MDA5 total IgG and IgG subclasses were measured using in-house enzyme-linked immunosorbent assays, and analysed in association with the patient prognosis.

RESULTS

In the training cohort, the concentrations of anti-MDA5 IgG1 and IgG3 in non-survivors were significantly higher than in survivors (P < 0.05), whereas there were no significant differences in the IgG2 and IgG4 levels. Kaplan-Meier survival analysis revealed that the levels of anti-MDA5 total IgG, IgG1 and IgG3 were associated with mortality (P < 0.05). Multivariate analysis revealed anti-MDA5 IgG1 >13 U/ml and anti-MDA5 IgG3 >11 U/ml were independent risk factors for death of DM-ILD patients (P < 0.05). Anti-MDA5 IgG1 was confirmed as an independent risk factor in the validation cohort, while anti-MDA5 IgG3 was not. Anti-MDA5 IgG1 showed greater discriminable power for patient prognosis (Youden index 0.494) than anti-MDA5 total IgG, IgG3, or the combination of IgG1 and IgG3 (Youden index 0.356, 0.32 and 0.447, respectively).

CONCLUSION

Anti-MDA5 IgG1 and IgG3 are significantly associated with poor prognosis in DM-ILD patients, and anti-MDA5 IgG1 is more efficient as a prognostic biomarker in DM-ILD patients.

Autoantibodies and Cancer Association: the Case of Systemic Sclerosis and Dermatomyositis

Several rheumatic diseases have a perplexing association with cancer. Unraveling this mysterious connection is likely to provide deeper understanding regarding mechanisms governing the onset of both autoimmunity and cancer immunity, in addition to providing clinicians much needed guidance around whom and when to screen for occult malignancy. Systemic sclerosis (scleroderma) and dermatomyositis are two diseases in which the association with internal malignancy is well-described and can be considered as models from which to gain important insights that likely have broader applicability. The past 15 years have witnessed a striking acceleration in understanding how these two diseases are related to cancer emergence-an important crack in this inscrutable armor has been the discovery and characterization of disease-specific autoantigens that are closely tied with risk of cancer emergence. The best-described examples of this are antibodies against anti-RNA polymerase III (anti-POL3) and transcription intermediary factor 1-gamma (anti-TIF1γ). Patients with systemic sclerosis and cancer that are diagnosed within a short time interval of each other frequently have anti-POL3 antibodies. Antibodies against the minor spliceosome protein RNA-Binding Region Containing 3 (RNPC3) are also associated with increased cancer incidence in systemic sclerosis. Similarly, in the dermatomyositis spectrum, the majority of anti-TIF1γ-associated cancers are detected around the time of DM onset (most often within 1 year). Antibodies against Nuclear Matrix Protein 2 are also potentially associated with increased cancer emergence in dermatomyositis. The systemic sclerosis/anti-POL3 connection with close cancer onset led to the first experiments directly supporting the concept that rheumatic disease may in fact be a manifestation of cancer. It is now clear that studying these diseases through the lens of autoantibodies can reveal relationships and insights that would otherwise remain obscured. Extending these studies, new findings show that antibodies against RNA polymerase I large subunit are associated with protection against short interval cancers in anti-POL3-positive systemic sclerosis patients. These insights highlight the fact that autoantigen discovery related to cancer emergence remains an important priority; such new tools will enable the testing of specific hypotheses regarding mechanisms governing disease emergence and development of effective anti-tumor responses. Autoantibody phenotype will likely play an important role in the development of cancer screening guidelines that are critically needed by clinicians taking care of these patients. In this review, we will summarize the current state of knowledge regarding the different ways in which autoantibodies are connected with systemic sclerosis/dermatomyositis and malignancy and highlight potential paths forward.

The five major autoimmune diseases increase the risk of cancer: epidemiological data from a large-scale cohort study in China

BACKGROUND

Cancer incidence and mortality have received critical attention during the long-term management of morbidities in patients with autoimmune diseases (AIDs). This study aimed to investigate and compare the risk of cancer associated with five major AIDs in a large-scale Chinese cohort.

METHODS

A total of 8,120 AID patients consecutively admitted to a national tertiary referral center in China were included and followed-up for 38,726.55 patient-years, including those with systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), Sjögren's syndrome (SS), systemic scleroderma (SSc), and idiopathic inflammatory myositis (IIM). Demographic data, cancer incidence, predilecting sites and cancer onset time were recorded and compared among the five AIDs.

RESULTS

Four hundred and thirty (5.3%) patients developed cancer. Their median age was 57.5 years and AID duration was 79.8 months. The estimated total standardized incidence ratio (SIR) of cancer in AIDs patients was 3.37, with the highest SIR observed in IIM (4.31), followed by RA (3.99), SSc (3.77), SS (2.88) and SLE (2.58). The increased SIR of cancers in AID patients showed a female predominance (female vs. male: 3.59 vs. 2.77) and younger patient involvement (age <50 vs. ≥50 years: 4.88 vs. 3.04). Patients with SLE had increased SIRs for developing hematologic malignancies and solid tumors located in the urinary bladder, corpus uteri and cervix uteri. Patients with SS had a significantly high SIR for developing non-Hodgkin's lymphoma. Within 3 years of IIM diagnosis, 74.6% of the patients developed cancer and they had a high risk of ovarian cancer. RA was associated with a wide distribution of scancers, including non-Hodgkin's lymphoma, gynecologic, urinary tract, thyroid gland and lung cancers. SSc patients had increased SIRs for developing cervical uterine, lung, and breast cancers.

CONCLUSION

Patients with five major AIDs in China had an increased risk of developing cancer, with a predominance in women and younger patients, although cancer incidence, predilection sites and cancer onset time may vary greatly in each AID entity.

Machine Learning Algorithms Identify Clinical Subtypes and Cancer in Anti-TIF1γ+ Myositis: A Longitudinal Study of 87 Patients

Background

Anti-TIF1γ antibodies are a class of myositis-specific antibodies (MSAs) and are closely associated with adult cancer-associated myositis (CAM). The heterogeneity in anti-TIF1γ+ myositis is poorly explored, and whether anti-TIF1γ+ patients will develop cancer or not is unknown at their first diagnosis. Here, we aimed to explore the subtypes of anti-TIF1γ+ myositis and construct machine learning classifiers to predict cancer in anti-TIF1γ+ patients based on clinical features.

Methods

A cohort of 87 anti-TIF1γ+ patients were enrolled and followed up in Xiangya Hospital from June 2017 to June 2021. Sankey diagrams indicating temporal relationships between anti-TIF1γ+ myositis and cancer were plotted. Elastic net and random forest were used to select and rank the most important variables. Multidimensional scaling (MDS) plot and hierarchical cluster analysis were performed to identify subtypes of anti-TIF1γ+ myositis. The clinical characteristics were compared among subtypes of anti-TIF1γ+ patients. Machine learning classifiers were constructed to predict cancer in anti-TIF1γ+ myositis, the accuracy of which was evaluated by receiver operating characteristic (ROC) curves.

Results

Forty-seven (54.0%) anti-TIF1γ+ patients had cancer, 78.7% of which were diagnosed within 0.5 years of the myositis diagnosis. Fourteen variables contributing most to distinguishing cancer and non-cancer were selected and used for the calculation of the similarities (proximities) of samples and the construction of machine learning classifiers. The top 10 were disease duration, percentage of lymphocytes (L%), percentage of neutrophils (N%), neutrophil-to-lymphocyte ratio (NLR), sex, C-reactive protein (CRP), shawl sign, arthritis/arthralgia, V-neck sign, and anti-PM-Scl75 antibodies. Anti-TIF1γ+ myositis patients can be clearly separated into three clinical subtypes, which correspond to patients with low, intermediate, and high cancer risk, respectively. Machine learning classifiers [random forest, support vector machines (SVM), extreme gradient boosting (XGBoost), elastic net, and decision tree] had good predictions for cancer in anti-TIF1γ+ myositis patients. In particular, the prediction accuracy of random forest was &gt;90%, and decision tree highlighted disease duration, NLR, and CRP as critical clinical parameters for recognizing cancer patients.

Conclusion

Anti-TIF1γ+ myositis can be separated into three distinct subtypes with low, intermediate, and high risk of cancer. Machine learning classifiers constructed with clinical characteristics have favorable performance in predicting cancer in anti-TIF1γ+ myositis, which can help physicians in choosing appropriate cancer screening programs.

Update on Malignancy in Myositis—Well-Established Association with Unmet Needs

Idiopathic inflammatory myopathies are a group of rare connective tissue diseases with a well-documented association with malignancy. The mechanisms underlying the increased risk of neoplasms in the course of myositis are not fully understood. The Pubmed database has been thoroughly screened for articles concerning cancer-associated myositis (CAM). The article summarizes the current state of knowledge on the epidemiology and pathogenesis of CAM. Furthermore, it analyses potential risk and protective factors for developing CAM, with particular emphasis on the association with distinct serological profiles. The review summarizes recommendations proposed so far for the management of CAM and presents a novel scheme for cancer screening proposed by the authors. Moreover, promising areas requiring further research were indicated.

Detecting Autoantibodies by Multiparametric Assays: Impact on Prevention, Diagnosis, Monitoring, and Personalized Therapy in Autoimmune Diseases

BACKGROUND

The introduction of multiparametric autoantibody tests has been proposed to improve the accuracy of the immunological diagnosis of autoimmune diseases (AID) and to accelerate time for completing the diagnostic process. Multiplex tests are capable of detecting many autoantibodies in a single run whereas a traditional immunoassay uses a single antigen to detect only a single specificity of autoantibodies. The reasons why multiplex tests could replace conventional immunoassays lie in the evidence that they allow for more efficient handling of large numbers of samples by the laboratory, while ensuring greater diagnostic sensitivity in AID screening.

CONTENT

This review aims to highlight the important role that multiparametric tests could assume when designed for defined profiles they are used not only for diagnostic purposes but also to predict the onset of AID to identify clinical phenotypes and to define prognosis. Furthermore, differences in the antibody profile could identify which subjects will be responsive or not to a specific pharmacological treatment.

SUMMARY

The use of autoantibody profiles, when specifically requested and performed with clinically validated technologies, can represent a significant step toward personalized medicine in autoimmunology.

Identification of distinct cytokine/chemokine profiles in dermatomyositis with anti-transcriptional intermediary factor 1-γ antibody

OBJECTIVES

Dermatomyositis (DM) and clinically amyopathic dermatomyositis (CADM) patients with positive expression of anti-transcription intermediary factor 1-γ (anti-TIF1-γ) antibody (Ab) are characterized by distinct clinicopathological features. We aimed to determine the role of cytokine/chemokine profiles in the classification of anti-TIF1-γ positive DM/CADM patients.

METHODS

Serum levels of 24 cytokines/chemokines were measured in 27 anti-TIF1-γ positive DM/CADM patients by a Luminex 200 system. Principal components analysis (PCA) and unsupervised hierarchical clustering were used to reduce variables and establish patient subgroups. Spearman's correlation coefficient was calculated between cytokine/chemokine levels and disease activity markers.

RESULTS

Among anti-TIF1-γ positive DM/CADM patients, two distinct patient clusters were identified. The diagnosis of CADM was more common in Cluster 1 than in Cluster 2 (58.3% vs 6.7%, p = 0.008). Skin disease activity was higher in Cluster 2 than in Cluster 1 as measured by CDASI-A (38.6 ± 10.4 vs 25.3 ± 10.0, p = 0.003). Patients within Cluster 2 exhibited significant muscle weakness (MRC ≤ 3, 33.3% vs 0.0%, p = 0.047), higher levels of anti-TIF1-γ Ab (92.4 ± 20.6 vs 66.9 ± 13.9, p = 0.001), and an increased malignancy rate (73.3% vs 25.0%, p = 0.021). Cluster 2 exhibited higher serum levels of CXCL10 (564.2 ± 258.8 vs 122.0 ± 97.8, p < 0.001), CCL2 (1136.6 ± 545.4 vs 441.6 ± 163.3, p < 0.001), Galectin-9 (38879.6 ± 20009.3 vs 12612.4 ± 6640.0, p < 0.001), IL-18 (436.1 ± 188.9 vs 243.0 ± 114.5, p = 0.003), TNF-α (9.3 ± 3.8 vs 5.6 ± 2.4, p = 0.007), and TNFRI (1385.1 ± 338.2 vs 2605.6 ± 928.5, p < 0.001) than Cluster 1.

CONCLUSION

In anti-TIF1-γ positive DM/CADM, we identified a "skin-predominant" cluster and a "hyperinflammation" cluster based on the cytokine/chemokine profiles. Cytokine/chemokine profiles in anti-TIF1-γ positive DM/CADM can identify discrete clusters of patients with different disease patterns, organ involvements, and clinical outcomes.

A systematic review and meta-analysis to inform cancer screening guidelines in idiopathic inflammatory myopathies

Objectives

To identify clinical factors associated with cancer risk in the idiopathic inflammatory myopathies (IIMs) and to systematically review the existing evidence related to cancer screening.

Methods

A systematic literature search was carried out on Medline, Embase and Scopus. Cancer risk within the IIM population (i.e. not compared with the general population) was expressed as risk ratios (RR) for binary variables and weighted mean differences (WMD) for continuous variables. Evidence relating to cancer screening practices in the IIMs were synthesized via narrative review.

Results

Sixty-nine studies were included in the meta-analysis. DM subtype (RR 2.21), older age (WMD 11.19), male sex (RR 1.53), dysphagia (RR 2.09), cutaneous ulceration (RR 2.73) and anti-transcriptional intermediary factor-1 gamma positivity (RR 4.66) were identified as being associated with significantly increased risk of cancer. PM (RR 0.49) and clinically amyopathic DM (RR 0.44) subtypes, Raynaud’s phenomenon (RR 0.61), interstitial lung disease (RR 0.49), very high serum creatine kinase (WMD −1189.96) or lactate dehydrogenase (WMD −336.52) levels, and anti-Jo1 (RR 0.45) or anti-EJ (RR 0.17) positivity were identified as being associated with significantly reduced risk of cancer. Nine studies relating to IIM-specific cancer screening were included. CT scanning of the thorax, abdomen and pelvis appeared to be effective in identifying underlying asymptomatic cancers.

Conclusion

Cancer risk factors should be evaluated in patients with IIM for risk stratification. Screening evidence is limited but CT scanning could be useful. Prospective studies and consensus guidelines are needed to establish cancer screening strategies in IIM patients.

TRIM33 gene somatic mutations identified by next generation sequencing in neoplasms of patients with anti-TIF1γ positive cancer-associated dermatomyositis

OBJECTIVE

To deep sequence the TRIM33 gene in tumours from patients with cancer-associated anti-TIF1γ autoantibody-positive dermatomyositis (DM) since TRIM33 somatic mutations in tumours may trigger this auto-immune disease.

METHODS

Next generation sequencing of tumour DNA samples from patients with cancer-associated anti-TIF1γ autoantibody-positive DM. Fourteen tumours from 13 anti-TIF1γ autoantibody-positive DM individuals were sequenced along with 2 control tumours from non-DM individuals.

RESULTS

Fourteen probable somatic variants from 4 tumours were identified in the TRIM33 gene.

CONCLUSION

These results are in accordance with the previous report of Pinal-Fernandez et al. and support the hypothesis of a role of TRIM33 gene mutations in the pathophysiology of anti-TIF1γ autoantibody-positive DM.

Distribution of anti-melanoma differentiation associated gene 5 (MDA5) IgG subclasses in MDA5+ dermatomyositis

OBJECTIVES

The anti-melanoma differentiation-associated gene 5 (MDA5) antibody is the main predictor of interstitial lung disease (ILD) in dermatomyositis (DM) and clinically amyopathic dermatomyositis (CADM). Nevertheless, a subset of MDA5+ patients have a favorable prognosis. We aimed to determine the possibility of using anti-MDA5 antibody isotypes and IgG subclasses for evaluating ILD risk.

METHODS

The isotypes (IgG, IgA and IgM) of anti-MDA5 were detected in serum samples of 36 anti-MDA5+ patients with DM/CADM using enzyme-linked immunosorbent assay (ELISA). IgG subclasses of anti-MDA5 antibodies were further investigated. Laboratory findings and cumulative survival were analyzed based on the isotypes of anti-MDA5 and subclasses of anti-MDA5 IgG.

RESULTS

Among the MDA5+ patients with DM/CADM, the positive rates of anti-MDA5 IgG, IgA, IgM were 100%, 97%, and 6%, respectively. The positive rates of anti-MDA5 IgG1, IgG2, IgG3, and IgG4 were 72%, 25%, 0%, and 28%, respectively. The incidence of acute interstitial pneumonia, mortality rate, and serum ferritin were significantly higher in anti-MDA5 IgG1+ patients than those in anti-MDA5 IgG1- patients with DM/CADM (P = 0.0027, 0.015, 0.0011, respectively). The sensitivity and specificity of anti-MDA5 IgG1 for predicting mortality were 100% and 41.7%, respectively. A combination of anti-MDA5 IgG1 and IgG4 for predicting mortality, yielded better specificity (87.5%).

CONCLUSION

IgA and IgG are the primary anti-MDA5 antibody isotypes. Anti-MDA5 IgG1 is the primary component of MDA5 IgG subclasses and anti-MDA5 IgG1 and IgG4 might serve as useful biomarkers for predicting mortality in DM-ILD.

Dermatomyositis autoantibodies: how can we maximize utility?

The past 15 years has seen significant advances in the characterization of myositis-specific autoantibodies (MSAs) and their associated phenotypes in patients with dermatomyositis (DM). As more careful studies are performed, it is clear that unique combinations of clinical and pathological phenotypes are associated with each MSA, despite the fact that there is considerable heterogeneity within antibody classes as well as overlap across the groups. Because risk for interstitial lung disease (ILD), internal malignancy, adverse disease trajectory, and, potentially response to therapy differ by DM MSA group, a deeper understanding of MSAs and validation and standardization of assays used for detection are critical for optimizing diagnosis and treatment. Like any test, the diagnostic sensitivity and specificity of assays for various MSAs is not perfect. Currently tests for MSAs are helpful at minimum for a clinician to assess relative risk or contribute to diagnosis and perhaps counsel the appropriate patient about what to expect. With international standardization and larger studies it is likely that more antibody tests will make their way into formal schemata for diagnosis and actionable risk assessment in DM. In this review, we summarize key considerations for interpreting the clinical and pathologic associations with MSA in DM and identify critical gaps in knowledge and practice that will maximize their clinical utility and utility for understanding disease pathogenesis.

Monitoring disease activity and damage in adult and juvenile idiopathic inflammatory myopathy

PURPOSE OF REVIEW

We have reviewed the literature to identify significant advances related to disease activity and damage in the idiopathic inflammatory myopathies (IIMs) from January 2019 to July 2020.

RECENT FINDINGS

New observations in the field from 2019 to 2020 have resulted in a better understanding of the clinical association and pathogenic origins of IIM. The use of patient-reported outcome measures and perspectives, identifying biomarkers and making better use of autoantibody testing are summarized. Basic sciences have led to an improved understanding of the role of NETosis in calcinosis, and of interferon type 1, in IIM. Preliminary insights are offered into Covid-19 in the setting of IIM, and the use of potential tools for monitoring disease remotely, which may assume larger importance for optimal disease management during a global pandemic. The wider exploration of newer imaging modalities and the use of nailfold capillaroscopy is a further step in better management of the condition.

SUMMARY

The summarized research in IIM is a step forward in being able to further define, and to distinguish disease activity from damage, in order to potentially aid future clinical diagnosis and management in this challenging disease.

Myositis autoantibodies: recent perspectives

PURPOSE OF REVIEW

To provide an overview of recent discoveries related to myositis-specific autoantibodies (MSAs) and assays used for their measurement.

RECENT FINDINGS

New autoantibody specificities have been reported including a MSA directed against eukaryotic initiation factor 3 and a myositis-associated autoantibody directed against heat shock factor 1. The association of anti-TIF1γ with cancer-associated dermatomyositis dependent on age has been confirmed in several large cohorts. Despite MSAs being almost entirely mutually exclusive, several myositis autoantigens are overexpressed in regenerating muscle and do not correlate with the corresponding MSA in any one patient. Further mechanisms may determine the final MSA specificity and are likely to include the need for autoantigen processing and presentation with adaptive T-cell help. The presence of CD4-positive T cells specific for histidyl tRNA synthetase protein in bronchial lavage fluid from antisynthetase patients lends support to this view. Finally, it is widely held that MSA do play an important role in clinical practice among some evidence and concern about commercial assay reliability.

SUMMARY

MSAs continue to provide important tools for clinical diagnosis and management as well as insights into disease mechanisms. Further improvement in the standardization and reliability of routine detection of MSAs is a high priority.

Clinical characteristics and prognostic analysis of Chinese dermatomyositis patients with malignancies

Although a strong association between idiopathic inflammatory myositis (IIM) and malignancy has been widely reported, few studies have solely focused on the concurrence of dermatomyositis (DM) and malignancies (DM-malignancy).We conducted a retrospective analysis of 37 DM-malignancy cases among 363 DM patients admitted to our hospital between January 2012 and December 2017.(1) The mean age at DM diagnosis was higher for DM-malignancy patients than for DM-non-malignancy patients [(54.76 ± 9.77) years vs (48.57 ± 12.82) years, t = 2.84, P = .005]. (2) Gynecological malignancies (35.90%/14 cases) were the most common malignancies. Malignancies were diagnosed before DM for 7 DM-malignancy patients. The interval between the DM and malignancy diagnoses for the remaining 32 DM-malignancy patients was less than 6 months for 18 patients (46.15%), less than 1 years for 23 patients (58.9%), and less than 2 years for 29 patients (74.26%). (3) There was no significant difference either in antinuclear antibody or anti-Ro-52 positivity between the 2 groups (P > .05). (4) Multivariate analysis demonstrated that DM onset age ≥50 years and concurrence with ILD increased the risk of death for DM patients [hazard ratio (HR): 1.62 and 2.72; 95% confidence interval (CI): (1.08-2.43) and (1.47-5.02); P = .02 and 0.001, respectively], and male gender decreased the risk of death [HR 0.66, 95% CI (0.44-0.98), P = .04]. DM-malignancy patients were older than DM-non-malignancy patients. Gynecological malignancies were the most common malignancies among these patients. A DM onset age ≥50 years, female sex and the presence of ILD were independent risk factors for death.

Hierarchical cluster analysis of cytokine profiles reveals a cutaneous vasculitis-associated subgroup in dermatomyositis

OBJECTIVES

Dermatomyositis (DM) is a chronic inflammatory autoimmune disease with notable heterogeneity. The intent of this study was to explore the difference in cytokine profiles of different subsets in DM based on the disease activity and myositis-specific antibodies, and to identify the clinical phenotypes associated with different cytokine profiles.

METHODS

Serum levels of 34 cytokines were prospectively measured in 47 consecutive DM patients and healthy controls. Concentrations of the cytokines were compared between the active and stable groups. Univariate and multivariate logistic regression models were used to identify the cytokines associated with DM disease activity. The cytokine profiles of anti-MDA5 and anti-TIF1γ subsets were compared, and the correlation analysis was performed between the elevated cytokines and clinical parameters in the two subsets. Hierarchical cluster analysis was used to establish clinical-cytokine subgroups in DM.

RESULTS

Serum levels of MIP-1α, IP-10, IL-8, IL-1RA, MCP-1, GRO-α, and IL-22 were significantly higher in DM patients compared with healthy controls. IP-10, IL-6, IL-1RA, IFN-α, and MCP-1 were significantly elevated in the DM-active subset than the DM-stable subset. The combination of three cytokines (IP-10, IL-1RA, and MCP-1) had a better performance in differentiating between the active subset and the stable subset than the conventional inflammatory markers. SDF-1α, IP-10, IL-7, IL-17A, RANTES, IFN-γ, TNF-α, MIP-1β, IFN-α, MCP-1, GRO-α, and IL-1α were significantly higher in the anti-MDA5 subset than in the TIF1γ subset. Cluster analysis revealed a hypercytokinemic-vasculitis subgroup in patients with DM.

CONCLUSIONS

Multiple cytokine signatures were depicted in different subsets of DM. A vasculitis-associated subgroup was firstly identified in DM with regards of cytokinome and deserves further mechanistic study. Key Points • The multivariate regression model of three cytokines (IP-10, IL-1RA, and MCP-1) could be a promising tool for distinguishing between the active and stable subset in DM. • Cytokine profiles of anti-MDA5-DM and anti-TIF1γ-DM were compared to identify the immunopathological differences between the two subsets. • Cluster analysis revealed a hypercytokinemic-vasculitis subgroup in patients with DM.

Anti-TIF1-γ autoantibodies: warning lights of a tumour autoantigen

Anti-transcription intermediary factor 1 (TIF1)-γ autoantibodies are robustly linked with cancer-associated DM in adults. This review aims to give an overview of the physiological context of TIF1-γ and to determine whether there is a pathophysiological link between anti-TIF1-γ autoantibodies and the occurrence of cancer. Detection of anti-TIF1-γ autoantibodies has a high sensitivity and specificity for cancer-associated DM in adults and is therefore useful for both diagnosis and cancer risk stratification. The function of the autoantigen, TIF1-γ, may provide insight into the mechanism behind this association. TIF1-γ is a ubiquitously present protein involved in various biological pathways, including TGF-β signalling. In cancer, it can act either as a tumour suppressor or promoter, depending on the cellular context and cancer stage. Evolving data provide pathophysiological insights, linking anti-TIF1-γ autoantibodies to both the anti-tumour response and to muscle and skin damage. TIF1-γ expression is increased in muscle and skin tissue of patients with DM. Mutations or loss-of-heterozygosity in TIF1-γ alleles in malignant tissue may result in the expression of tumour-specific neo-antigens stimulating autoantibody production. The newly formed autoantibodies are hypothesized to cross-react with antigens in muscle and skin, driving the development of DM. Based on the current evidence, anti-TIF1-γ autoantibodies should be considered warning lights of a potential tumour autoantigen and should alert the physician to the possibility of an underlying cancer.

[Dermatomyositis: new antibody, new classification]

Dermatomyositis are rare chronic auto-immune diseases characterized by cutaneous involvement. Diagnosis could be made in childhood or in aldult. There are some different clinical and histological presentation associated with different myositis specific antibody. There are five dermatomyositis specific autoantibodies, anti-Mi2, anti-Tif1-γ, anti-NXP2, anti-MDA5, and anti-SAE. Anti-Mi2 are associated with "classical form" of DM with cutaneous and muscular involvement. Anti-Tif1γ and anti-NXP2 are found in juvenile and adult dermatomyositis, and are associated with recurrent diseases with cutaneous involvement at the forefront. In adults, they are associated with cancer. Anti-MDA5 antibodies are associated with a systemic involvement and an interstitial lung disease. Finally, anti-SAE have been found only in adults, with a classic form.