Increase in Mitochondrial Mass of Lymphocyte Subsets in Anti-MDA5 and TIF1-γ-Positive Dermatomyositis Patients.

OBJECTIVES: The mitochondrial function in anti-MDA5 and TIF1-γ-positive dermatomyositis (DM) is relatively unknown. This study attempted to explore mitochondrial mass within the peripheral lymphocyte subsets of anti-MDA5 and TIF1-γ-positive DM. METHODS: This cross-sectional study enrolled 109 DM patients and 32 healthy controls (HCs). The mitochondrial mass of peripheral lymphocyte subsets was analyzed via flow cytometry using median fluorescence intensity assessment. RESULTS: Compared with HCs, there was an abnormal change in peripheral lymphocyte subsets in anti-MDA5 and anti-TIF1-γ-positive DM patients. Anti-MDA5 and anti-TIF1-γ-positive DM patients also exhibited a significantly elevated mitochondrial mass in peripheral lymphocyte subsets. Furthermore, anti-MDA5 antibody levels were positively associated with the mitochondrial mass of most lymphocyte subsets in anti-MDA5-positive DM patients. Univariate logistic regression analysis indicated that the increased mitochondrial mass in some peripheral lymphocyte subsets was related to the occurrence of anti-MDA5-positive DM and presence of anti-MDA5 antibodies. Similar results were obtained in anti-TIF1-γ-positive DM patients. CONCLUSIONS: Abnormal lymphocyte subset counts and percentages as well as altered mitochondrial mass in anti-MDA5 and TIF1-γ-positive DM patients were associated with anti-MDA5 and TIF1-γ antibodies. We believe that these results may provide novel mitochondria-based insights into DM pathogenesis.

Long-term risks of malignancy in myositis-specific antibody-positive idiopathic inflammatory myopathy.

To identify the long-term risks of malignancy in patients with myositis-specific antibody (MSA)-positive idiopathic inflammatory myopathy (IIM). This retrospective cohort study included 216 IIM patients (aged > 18 years). Of these, 109 patients were positive for antibodies against anti-aminoacyl-tRNA synthetase (ARS), melanoma differentiation-associated gene 5 (MDA5), Mi-2, and transcriptional intermediary factor 1-γ (TIF1-γ). Age- and sex-matched standardized incidence ratios (SIRs) were calculated to compare the incidence of malignancy in IIM patients to that of the general population. The malignancy-free survival rate was estimated by Kaplan-Meier methods. Our study included 109 patients, 64 with anti-ARS, 28 with anti-MDA5, 9 with anti-Mi-2, and 8 with anti-TIF1-γ antibodies; 16 and 5 patients were diagnosed with a malignancy within 3 years before or after and within 4 to 10 years after their IIM onset, respectively. The SIRs of malignancy within 3 years of IIM onset for each MSA were calculated as follows: 2.12 (95% confidence interval [CI] 0.98-4.35) for anti-ARS, 1.87 (95% CI 0.48-4.97) for anti-MDA5, 2.11 (95% CI 0.11-13.69) for anti-Mi-2, and 9.30 (95% CI 2.98-25.58) for anti-TIF1-γ antibodies. The SIR at 4 to 10 years after IIM onset in patients with an anti-MDA5 antibody was 4.62 (95% CI 1.19-14.72); other MSAs did not have statistically significant SIRs. The long-term SIR of malignancy in patients with an anti-MDA5 antibody was 4.62 (95% CI 1.19-14.72), and the SIR among patients with an anti-TIF1-γ antibody within 3 years of IIM onset was 9.30 (95% CI 2.98-25.58). Screening for malignancies in patients with late phase of IIM and an anti-MDA5 antibody may be beneficial.

Development of dermatomyositis after anti-transcriptional intermediary factor 1-γ antibody seroconversion during treatment for small cell lung cancer.

BACKGROUND: Inflammatory myositis, such as dermatomyositis, is sometimes complicated by cancer and is recognized as cancer-associated myositis. Although some autoimmune antibodies are considered to be involved in the development of myositis in cancer patients, the precise mechanism has not been clarified. The findings of the present case shed light on the mechanism by which anti-transcriptional intermediary factor 1 (TIF1)-γ Ab was produced and the pathogenesis of cancer-associated myositis. CASE PRESENTATION: We describe a case of dermatomyositis that developed in a 67-year-old man who had been diagnosed with small cell lung cancer of clinical T4N3M0 stage IIIB/limited disease during treatment. He received systemic chemotherapy and radiation therapy, and dermatomyositis developed along with a significant decrease in tumor size. TIF1-γ Ab, which is one of the myositis-specific antibodies, was found to be seroconverted. In addition, immunohistochemical analysis showed that cancer cells were positive for the TIF1-γ antigen. CONCLUSION: The findings of the present case suggest that transcriptional intermediary factor 1-γ, which is released from tumor cells, induces the production of TIF1-γ Ab, leading to the development of dermatomyositis.

Recent research on myositis-specific autoantibodies in juvenile dermatomyositis. / å¹¼å¹´åž‹çš®è‚Œç‚Žç‰¹å¼‚æ€§æŠ—ä½“ç ”ç©¶è¿›å±•.

Juvenile dermatomyositis (JDM) is an autoimmune disease manifesting as proximal muscle weakness and skin rash and can involve multiple systems and visceral organs. Myositis-specific autoantibodies (MSAs) are highly associated with various complications and prognosis in JDM. Patients with anti-Mi-2 antibodies tend to have good prognosis and typical clinical symptoms. Patients with anti-MDA5 antibodies often have diffuse interstitial lung disease and skin ulcer, with mild symptoms of myositis. Patients with anti-NXP2 antibodies often have calcinosis, and such antibodies are associated with gastrointestinal bleeding and perforation. Patients with anti-TIF1-γ antibodies have diffuse and refractory skin lesions. Anti-SAE antibodies are rarely detected in children, with few reports of such cases. This article reviews the features of clinical phenotypes in JDM children with these five types of MSAs, so as to provide a basis for the clinical treatment and follow-up management of children with JDM.

Coexistence of anti-KS and anti-TIF1-γ antibodies in clinically amyopathic dermatomyositis presenting with rapid progression of interstitial lung disease.

Polymyositis/Dermatomyositis (PM/DM) is an idiopathic inflammatory myopathy (IIM) manifesting mainly as symmetrical proximal muscle weakness and/or typical cutaneous features due to autoimmune mechanisms. Clinically amyopathic dermatomyositis (CADM) is a subset of DM that exhibits only the typical cutaneous features without any clinical muscle symptoms. Several autoantibodies have been found specifically in patients with PM/DM, including CADM patients. Anti-KS antibody is one of a group of anti-aminoacyl transfer RNA (ARS) antibodies that are mainly associated with fever, Raynaud's phenomenon, polyarthritis, and interstitial lung disease (ILD), whereas anti-TIF1-γ antibody is frequently found in DM patients with malignancy. Here, we report a CADM patient having both anti-KS antibody and anti-TIF1-γ antibody. This patient developed an acute exacerbation of ILD and was successfully treated with high dose corticosteroid pulse therapy together with immunosuppressive agents. Although earlier experience had indicated that the seminal characteristic of anti-KS-positive ILD was slowly developing disease onset with little or no progression over the clinical course, the present patient suffered rapidly progressive disease.

Circulating VEGF-A, TNF-α, CCL2, IL-6, and IFN-γ as biomarkers of cancer in cancer-associated anti-TIF1-γ antibody-positive dermatomyositis.

OBJECTIVES: The objective of the current study was to detect plasma profiles of inflammatory cytokines for determining potential biomarkers indicating cancer presence among the anti-TIF1-γ antibody-positive dermatomyositis (DM) patients. METHODS: Twenty-seven cancer-associated anti-TIF1-γ antibody-positive DM (Cancer TIF1-γ-DM) patients were compared with 20 anti-TIF1-γ antibody-positive DM patients without cancer (Non-cancer TIF1-γ-DM) and 10 healthy controls (HC). The plasma levels of 17 cytokines were determined using the Luminex 200 system. The ability of plasma VEGF-A, TNF-α, CCL2, IL-6, and IFN-γ levels to distinguish the presence of cancer was evaluated through the area under the curve (AUC) analysis. Potential protein interactions of TIF1-γ and the five cytokines were analyzed using the STRING database. RESULTS: VEGF-A, TNF-α, CCL2, IL-6, and IFN-γ plasma levels were significantly higher in the Cancer TIF1-γ-DM group, especially those without any anticancer treatment, than those in the non-cancer TIF1-γ-DM and HC groups. Meanwhile, anti-TIF1-γ antibody and the five cytokines could distinguish cancer presence in anti-TIF1-γ antibody-positive DM patients. The STRING network indicated that TIF1-γ potentially interacted with the cytokines. Positive correlations of VEGF-A among CCL2, IL-6, and IFN-γ and between IFN-γ and IL-6 were observed in Cancer TIF1-γ-DM patients. VEGF-A, TNF-α, CCL2, and IL-6 were positively associated with muscle-associated enzymes among the Cancer TIF1-γ-DM patients. CONCLUSION: The present study identified VEGF-A, TNF-α, CCL2, IL-6, and IFN-γ as significant potential biomarkers indicating the presence of cancer and demonstrated a more detailed cytokine profile during diagnosis. These biomarkers could provide better screening strategies and insight into the Cancer TIF1-γ-DM pathogenesis. Key Points • VEGF-A, TNF-α, CCL2, IL-6, and IFN-γ are potential biomarkers of cancer in cancer-associated anti-TIF1-γ antibody-positive dermatomyositis. Potential pathogenic molecular mechanism of the cancer-associated anti-TIF1-γ antibody-positive dermatomyositis.

Anti-TIF1γ antibody-positive dermatomyositis associated with nivolumab administration in a patient with advanced oesophageal squamous cell carcinoma: A case report and literature review.

We report a case of anti-transcriptional intermediary factor 1γ antibody-positive dermatomyositis following nivolumab treatment. The patient was successfully treated with pulse steroid therapy and high-dose intravenous immunoglobulin, followed by oral glucocorticoid treatment. Immune checkpoint inhibitors, such as nivolumab, may induce not only myositis as an immune-related adverse event but also dermatomyositides as a paraneoplastic syndrome by distracting immune tolerance. Differentiating between pathologies is warranted if patients develop myositis after immune checkpoint inhibitor administration.

A Case in Which Breast Cancer Developed at the Same Time As Dermatomyositis, and the Onset of New Cancer Was Able to Be Predicted by the Exacerbating Skin Symptoms and Parallel Increase in the Anti-TIF1-γ Antibody Levels.

Dermatomyositis (DM) is an idiopathic inflammatory myopathy. The incidence of malignancy in DM patients is quite high. Anti-transcription intermediary factor 1-γ (anti-TIF1-γ) antibody is more prevalent in DM patients with malignancy than in those without malignancy. A 70-year-old woman developed hoarseness and difficulty swallowing. A physical examination revealed skin abnormalities. Breast cancer was found in her right breast. She was positive for anti-TIF1-γ antibody. Chemotherapy reduced the tumor size, decreased the anti-TIF1-γ antibody level, and improved her symptoms. About 2.5 years later, however, her skin symptoms worsened, and anti-TIF1-γ antibody levels increased again, and colorectal cancer was found. Treatment with endoscopic mucosal resection (EMR) improved her symptoms again. Our case suggests that the exacerbating skin symptoms and parallel increase in the anti-TIF1-γ antibody level led to the detection of a second cancer after treatment of the first cancer in this case of DM.

Age distribution and prevalence in different age groups of four myositis-specific autoantibodies, including anti-ARS, anti-MDA5, anti-Mi-2, and anti-TIF1γ antibodies.

We accumulated the demographic information and analyzed the prevalence of myositis-specific antibodies (MSAs) in a large cohort across Japan as standard testing for MSAs becomes more widely available. This retrospective, observational, cohort study analyzed the records of individuals aged 0-99 years who are tested for serum MSAs at SRL Incorporation from January 2014 to April 2020 across Japan. An enzyme-linked immunosorbent assay testing was applied to determine the presence of anti-aminoacyl tRNA synthetase (anti-ARS), anti-Mi-2, anti-melanoma differentiation-associated gene 5 (anti-MDA5), or anti-transcriptional intermediary factor 1-γ (anti-TIF1γ) (Medical and Biological Laboratories). Anti-TIF1γ antibody was detected more in male patients than female patients. In contrast, women were predominant in patients with other MSAs. More than half of the anti-ARS or anti-TIF1γ antibody-positive patients were over 60 years old, although anti-MDA5 or anti-Mi-2-positive patients were mostly under <60 years old. Anti-MDA5 antibody-positive patients were mostly aged 40-59 years, while other MSA groups were mostly 60-79 years. Anti-MDA5 antibody was detected most frequently in the age range of 0-29 years. Anti-TIF1γ antibody was the second most commonly detected autoantibody in the age range of 0-19 years. Anti-ARS antibody was the most frequently detected autoantibody after the age of 30 years, and the frequency of anti-ARS gradually increased at more advanced ages. The second and third most detected autoantibodies were anti-MDA5 and anti-TIF1γ, respectively, in ages 30-79 years. We performed a nationwide >3-year evaluation of MSA detection in a routine diagnostic setting. This paper provides clinical images concerning the relationship between four MSA types and the distribution of sex and age in a large population.

Cancer associated autoantibodies in idiopathic inflammatory myopathies: A retrospective cohort from a single center in China.

OBJECTIVES: Idiopathic inflammatory myopathies (IIMs) are systemic, heterogeneous diseases, which mainly affect skeletal muscle. Myositis with cancer is often referred to as cancer-associated myositis (CAM), which is associated with poor prognosis. This study aimed to determine the cancer associated myositis-specific autoantibodies (MSAs) and to elucidate their associations with clinical features in Chinese patients with IIMs. METHODS: This retrospective study enrolled 312 patients with IIMs who were treated at Tianjin Medical University General Hospital, China, from January 2015 to December 2020. Clinical data were collected. Serum MSAs, including anti-Mi-2, anti-TIF1-γ, anti-NXP2, anti-SAE, anti-MDA5, anti-SRP, anti-Jo-1, anti-PL-7, anti-PL-12, anti-OJ, anti-EJ and anti-HMGCR antibodies were detected. Cancer-associated MSAs, their phenotypic and survival features were estimated through SPSS 20.0. RESULTS: The results revealed that anti-TIF1-γ antibody and anti-SAE antibody were cancer-associated autoantibodies with odds ratios (95% CI) of 8.70 (3.35-22.64) and 22.31 (4.32-115.05), respectively. Skin lesions, proximal weakness, dysphagia and dysarthria were observed more frequently in patients carrying anti-TIF1-γ antibody. By contrast, patients with anti-TIF1-γ antibody had a lower frequencies of fever, arthritis/arthralgia and interstitial lung disease (ILD). Anti-TIF1-γ antibody positive CAM comprised about half of CAM entities and had the characteristic of close temporal association with cancer detection/recurrence. Female-dominant, common reproductive system tumors were other clinical features of this subset. Besides, patients with anti-TIF1-γ antibody positive had significantly lower survival rates than the anti-TIF1-γ antibody negative group. CONCLUSIONS: Anti-TIF1-γ antibody and anti-SAE antibody were cancer-associated autoantibodies. Anti-TIF1-γ antibody positive CAM was a subset that comprised about half of CAM entities and had the characteristic of poor prognosis.

Immune checkpoint inhibitor therapy in a patient with small cell lung cancer and anti-transcriptional intermediary factor 1-γ antibody-positive dermatomyositis: A case report.

Autoimmune diseases (ADs) are closely related to cancers; 30% of dermatomyositis (DM) cases are associated with malignancy. In lung cancer patients accompanied by DM, the most frequent cancer type is small cell lung cancer (SCLC). Anti-transcriptional intermediary factor 1 γ (anti-TIF1γ) antibody is a promising marker for the assessment of cancer risk in DM patients. The recent use of immune checkpoint inhibitors (ICIs) for extensive-stage SCLC has improved patient outcomes. However, clinical trials of ICI excluded most patients with ADs because of the increased risk of toxicity. Nevertheless, recent evidences suggest that ICI may be appropriate for AD patients. A 76-year-old man diagnosed with extensive-stage SCLC and anti-TIF1γ Ab-positive DM developed limb weakness and typical skin manifestations of DM. Positron emission tomography-computed tomography showed diffuse uptake in all muscles. The results of a nerve conduction study and electromyography were consistent with acute myopathy. Electron microscopy showed tubuloreticular inclusions in endothelial cells. He was treated with corticosteroids for DM and chemotherapy with atezolizumab for SCLC. Despite concerns regarding the use of ICI because of DM, atezolizumab was administered under close observation. After treatment, tumor size decreased and his symptoms improved significantly. We believe that the response of SCLC to chemotherapy including ICI, had a positive effect on the improvement of DM. Clinicians should consider ICIs for SCLC patients with DM and carefully monitor the patient's symptoms during treatment.

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 >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.

Clinical value of cancer-associated myositis-specific antibodies, anti-transcriptional intermediary factor 1-γ, and anti-nuclear matrix protein 2 antibodies in a retrospective cohort of dermatomyositis/polymyositis in a Japanese community hospital.

Among the myositis-specific antibodies (MSA), anti-transcriptional intermediary factor 1 (TIF1)-γ and anti-nuclear matrix protein 2 (NXP2) antibodies are reportedly associated with cancer-associated myositis (CAM). We aimed to investigate patient characteristics of CAM and the clinical role of cancer-associated MSA (caMSA) in a retrospective cohort from a city hospital. All patients visiting our department between April 2014 and October 2021 with newly diagnosed dermatomyositis, polymyositis, and clinically amyopathic dermatomyositis were included. Anti-TIF1-γ and anti-NXP2 antibodies were collectively considered as caMSA. First, we compared clinical characteristics in CAM, defined as cases showing onset or recurrence of malignancy within 5 years, versus non-CAM. Second, we investigated independent risk factors for CAM. Third, we compared clinical characteristics with and without caMSA within CAM. Finally, we investigated whether caMSA was predictive of poor prognosis. The cohort of 39 patients included 12 (30.7%) CAM cases. Compared with non-CAM, CAM had significantly more dermatomyositis and higher frequencies of dysphagia, anti-TIF1-γ antibody, and caMSA. Using logistic regression analysis, caMSA was an independent risk factor for CAM. In a comparison between caMSA and non-caMSA within CAM, caMSA was associated with higher frequencies of stage ≥ II. However, caMSA did not necessarily indicate a poor prognosis. Only caMSA represented an independent risk factor for CAM and showed a significant association with advanced cancer. Key Points • Cancer-associated MSA was an independent risk factor for cancer-associated myositis. • Cancer-associated MSA was associated with advanced cancer.

Clinical Characteristics of Anti-TIF-1γ Antibody-Positive Dermatomyositis Associated with Malignancy.

We retrospectively analyzed the clinical and laboratory data of patients diagnosed with anti-transcriptional intermediary factor 1 (TIF-1γ) antibody-positive polymyositis (PM)/dermatomyositis (DM) to clarify the characteristics of this disease. We identified 14 patients with TIF-1γ antibody-positive DM (TIF-1γ DM), 47 with anti-aminoacyl-tRNA synthetase antibody (ARS)-positive PM/DM, and 24 with anti-melanoma differentiation-associated gene 5 antibody (MDA-5)-positive PM/DM treated at the Kurume University Hospital between 2002 and 2020. Patients with TIF-1γ DM were significantly older than the other two groups. Nine patients with TIF-1γ DM were female, thirteen patients had DM, and one had clinically amyopathic DM. Primary malignant lesions were lung (3), uterus (2), colon (2), breast (2), ovary (1), lymphoma (1), and unknown (2). Cutaneous manifestation and dysphagia were the most common symptoms in TIF-1γ DM. Erythema (9/14), the V-neck sign (8/14), heliotrope (9/14), and nailfold telangiectasia (14/14) were significantly more common in TIF-1γ DM. Furthermore, no patients with TIF-1γ DM had interstitial lung abnormality on high-resolution CT. In patients with TIF-1γ DM, the frequency of dysphagia and unusual erythema, particularly that which spreads from the trunk, and nailfold telangiectasia, were characteristic findings. In most patients with TIF-1γ DM, it is necessary to administer other immunosuppressive drugs along with glucocorticoids.

Rapid changes of nailfold capillary abnormalities during treatment for a patient with dermatomyositis complicated by lung cancer: a case report.

Nailfold capillary abnormalities are typically observed in patients with systemic sclerosis and are also often found in patients with polymyositis (PM) and dermatomyositis (DM). Nailfold capillary abnormalities in some patients with PM/DM were found to improve with immunosuppressant treatment. However, the short-term changes in nailfold capillaries and their associations with disease activity have not been established yet. Additionally, there have been no reports on whether nailfold capillary abnormalities can change during the progression of malignant tumours. A man in his 60s with anti-transcriptional intermediate factor 1γ (anti-TIF-1γ) antibody-positive DM complicated with small cell lung carcinoma was treated with prednisolone (PSL) 70 mg, carboplatin (CBDCA) and etoposide (VP-16). His nailfold capillary abnormalities improved rapidly, and the tumour size decreased with treatment. Although chemotherapy was continued, abnormalities in the nailfold capillaries gradually recurred. The worsening of the capillary abnormalities prompted us to examine computed tomography scans, which showed the recurrence of lung cancer. After switching to second-line chemotherapy, the change in the nailfold capillary abnormalities was again in a parallel course with the disease status of lung cancer. Changes in nailfold capillaries may be useful not only for the diagnosis but also for the evaluation of the recurrence of malignant tumours with DM.

Anti-transcription intermediary factor 1 gamma (TIF1γ) antibody-positive dermatomyositis associated with ascending colon cancer: a case report and review of the literature.

BACKGROUND: Anti-transcriptional intermediary factor 1 gamma (TIF1γ) antibody is a marker for predicting cancer association in patients with dermatomyositis (DM). The overall survival rate in DM patients with cancer was reported to be considerably worse than that in DM patients without cancer. However, the treatment for cancer-associated DM remains controversial, because the treatment priority between surgical resection for the tumor and internal treatments, including glucocorticoids, immunosuppressive agents, and intravenous immune globulin, has not been established. CASE PRESENTATION: We report the case of a 57-year-old Japanese man diagnosed with anti-TIF1γ antibody-positive DM associated with ascending colon cancer. His clinical symptoms included facial and brachial edema, muscle weakness, dysphagia, myalgia, and rash. Physical examination revealed periorbital edema and Gottron's papules over his knuckles with brachial edema, and tenderness and weakness of the proximal limb muscles. The findings of hyperintense muscles in T2-weighted sequences of brachial contrast-enhanced magnetic resonance imaging and the infiltration of lymphocytic cells and CD4-positive lymphocytes from muscle biopsy were compatible with the diagnostic criteria for dermatomyositis. Anti-TIF1γ antibody was positive by immunoprecipitation assay. He first started internal treatment including intravenous immunoglobulin, steroid pulse, prednisolone, and azathioprine, followed by surgical resection for the tumor because of the elevation of creatine kinase and progression of dysphagia. However, clinical symptoms did not improve, and the patient died 6 months later. CONCLUSIONS: We faced difficulties in determining the treatment priority between surgical resection and internal treatment for our case; therefore, this case would be educational for readers. We searched PubMed to identify English-language case reports of anti-TIF1γ antibody-positive dermatomyositis with malignancy and found 21 reported cases. We herein review and summarize previously reported cases of anti-TIF1γ antibody-positive DM with malignancy. Cancer screening is essential in patients with anti-TIF1γ antibody-positive dermatomyositis because it is associated with a high prevalence of malignancies. Our review revealed that initial surgical treatment should be recommended for better prognosis if the general condition allows.

Transcriptional intermediary factor 1 (TIF1) and anti-TIF1γ antibody-positive dermatomyositis.

Recently, great advancements have been made towards understanding the mechanisms underlying dermatomyositis (DM). Many novel autoantibodies, such as anti-MDA5, anti-TIF1γ, anti-NXP2, and anti-SAE, have been reported to be involved in DM. DM is now classified based on these myositis-specific autoantibodies. Anti-TIF1γ antibodies are closely associated with juvenile DM and adult cancer-associated DM. Anti-TIF1γ antibody-positive DM tends to present severe cutaneous manifestations, mild myositis, and dysphagia. TIF1γ (also known as TRIM33) plays a role in transcriptional elongation, DNA repair, differentiation of cells, embryonic development, and mitosis. Moreover, TIF1γ has been shown to suppress various tumors via the TGF-ß/Smad and the Wnt/ß-Catenin signaling pathways. In this review, we explore the relationship between TIF1γ, cancer, and DM. We also discuss the pathogenesis of anti-TIF1γ antibody-positive DM.

Clinical and laboratory parameters predicting cancer in dermatomyositis patients with anti-TIF1γ antibodies.

BACKGROUND: Dermatomyositis (DM) is a chronic acquired autoimmune disorder strongly associated with cancer development. Until now, identifying predictive markers indicating a high risk of cancer has challenged clinicians. Although anti-TIF1γ antibody is a major serological indicator for cancer-associated DM, many anti-TIF1γ antibody-positive DM patients lack malignancy. OBJECTIVES: To determine clinical and laboratory parameters that support cancer prediction in anti-TIF1γ antibody-positive DM patients. METHODS: Clinical and laboratory data were collected from cancer-associated and unassociated DM patients with anti-TIF1γ antibodies. Serum cytokine concentrations were measured with a cytokine array assay. The values of inflammatory cytokines in cancer prognosis were determined with a receiver operating characteristic curve analysis. RESULTS: The cancer group had a significantly higher frequency of males, older mean age and higher anti-TIF1γ antibody levels. Some inflammatory cytokines, particularly tumour necrosis factor (TNF) and TNF receptor superfamilies, had increased levels in sera that were correlated with myositis markers, cutaneous severity and DM disease activity. Moreover, these cytokines had an area under the curve (AUC) ≥0.8 and high sensitivity and specificity at their specific cut-off, even higher than anti-TIF1γ levels in cancer prediction in our DM patients. CONCLUSIONS: Our results suggest a close pathophysiological relationship among myositis, cancer and skin involvements in DM patients with anti-TIF1γ antibodies and the potential clinical significance of anti-TIF1γ antibody levels in evaluating disease severity and prognosis in DM patients. Some inflammatory cytokines, particularly TNF and TNF receptor superfamilies including BAFF, sTNF-R1 and sTNF-R2, may support cancer prediction in DM patients with anti-TIF1γ antibodies.

Presence of anti-transcriptional intermediary factor-1 gamma antibodies in a dermatomyositis patient with retroperitoneal cancer of unknown primary site.

A 71-year-old woman with dermatomyositis (DM) received glucocorticoid steroid (GCS) and tacrolimus treatment. Relapse of skin symptoms was observed after tapering the GCS dose, and the patient tested positive for anti-transcriptional intermediary factor-1 gamma (TIF1-γ) antibody. Examinations for malignancy were repeatedly performed. However, no obvious findings indicative of a tumour were observed. Two years after, a retroperitoneal tumour was detected and pathologically diagnosed as poorly differentiated adenocarcinoma. The patient developed intestinal and biliary obstruction and eventually died of sepsis. Herein, we report the presence of anti-TIF1-γ antibodies in a DM patient with cancer of unknown primary site.