Prevalence, tropism, and activity of cutavirus in circulating blood lymphocytes, stool, and skin biopsy specimens of patients with cutaneous T-cell lymphoma and parapsoriasis en plaques.

A significant association has been established between a newly emerging human parvovirus, cutavirus (CuV), and cutaneous T-cell lymphoma/mycosis fungoides (CTCL/MF) and its precursor parapsoriasis en plaques (PP). CTCL is a heterogeneous group of skin malignancies of T cells, the cause of which remains unknown. This study aimed to determine the activity, spread, and cell tropism of the skin-persistent CuV. CuV DNA was detected in both skin biopsies (6/20, 30%) and peripheral blood mononuclear cells (PBMCs) (4/29, 13.8%) from 49 CTCL/MF or PP patients, while none from 33 patients with any other type of skin disease or healthy subjects harbored CuV DNA. CuV DNA persisted in the skin or PBMCs for up to 15 years, despite circulating CuV-specific IgG. Spliced CuV mRNA was expressed in skin, indicating viral activity. Also, both of two available stool samples contained encapsidated CuV genomes, suggesting that the patients excrete infectious virus into the environment. Finally, CuV was observed to target circulating and skin-resident CD4 + T cells and some skin keratinocytes and macrophages. This is especially intriguing as malignant T cells in CTCL develop from CD4 + T cells. Hence, CuV should be further investigated for the overall role it plays in the complex tumor microenvironment of CTCL/MF.

A Germinal Center Checkpoint of AIRE in B Cells Limits Antibody Diversification.

In response to antigens, B cells undergo affinity maturation and class switching mediated by activation-induced cytidine deaminase (AID) in germinal centers (GCs) of secondary lymphoid organs, but uncontrolled AID activity can precipitate autoimmunity and cancer. The regulation of GC antibody diversification is of fundamental importance but not well understood. We found that autoimmune regulator (AIRE), the molecule essential for T cell tolerance, is expressed in GC B cells in a CD40-dependent manner, interacts with AID and negatively regulates antibody affinity maturation and class switching by inhibiting AID function. AIRE deficiency in B cells caused altered antibody repertoire, increased somatic hypermutations, elevated autoantibodies to T helper 17 effector cytokines and defective control of skin Candida albicans. These results define a GC B cell checkpoint of humoral immunity and illuminate new approaches of generating high-affinity neutralizing antibodies for immunotherapy.

EORTC consensus recommendations for the treatment of mycosis fungoides/Sézary syndrome - Update 2023.

On behalf of the EORTC Cutaneous Lymphoma Tumours Group (EORTC-CLTG) and following up on earlier versions published in 2006 and 2017 this document provides an updated standard for the treatment of mycosis fungoides and Sézary syndrome (MF/SS). It considers recent relevant publications and treatment options introduced into clinical practice after 2017. Consensus was established among the authors through a series of consecutive consultations in writing and a round of discussion. Treatment options are assigned to each disease stage and, whenever possible and clinically useful, separated into first- and second line options annotated with levels of evidence. Major changes to the previous version include the incorporation of chlormethine, brentuximab vedotin, and mogamulizumab, recommendations on the use of pegylated interferon α (after withdrawal of recombinant unpegylated interferons), and the addition of paragraphs on supportive therapy and on the care of older patients. Still, skin-directed therapies are the most appropriate option for early-stage MF and most patients have a normal life expectancy but may suffer morbidity and impaired quality of life. In advanced disease treatment options have expanded recently. Most patients receive multiple consecutive therapies with treatments often having a relatively short duration of response. For those patients prognosis is still poor and only for a highly selected subset long term remission can be achieved with allogeneic stem cell transplantation. Understanding of the disease, its epidemiology and clinical course, and its most appropriate management are gradually advancing, and there is well-founded hope that this will lead to further improvements in the care of patients with MF/SS.

Significant Association of Cutavirus With Parapsoriasis en Plaques: High Prevalence Both in Skin Swab and Biopsy Samples.

Cutavirus (CuV) is associated with cutaneous T-cell lymphoma (CTCL), of which parapsoriasis is a precursor. Our study reveals a significantly higher CuV-DNA prevalence in skin swabs of parapsoriasis patients (6/13; 46.2%) versus those of healthy adults (1/51; 1.96%). Eight patients (8/12; 66.7%) had CuV DNA in biopsied skin, and 4 developed CTCL.

The Transcription Factor Twist1 Has a Significant Role in Mycosis Fungoides (MF) Cell Biology: An RNA Sequencing Study of 40 MF Cases.

The purpose of this RNA sequencing study was to investigate the biological mechanism underlying how the transcription factors (TFs) Twist1 and Zeb1 influence the prognosis of mycosis fungoides (MF). We used laser-captured microdissection to dissect malignant T-cells obtained from 40 skin biopsies from 40 MF patients with stage I-IV disease. Immunohistochemistry (IHC) was used to determinate the protein expression levels of Twist1 and Zeb1. Based on RNA sequencing, principal component analysis (PCA), differential expression (DE) analysis, ingenuity pathway analysis (IPA), and hub gene analysis were performed between the high and low Twist1 IHC expression cases. The DNA from 28 samples was used to analyze the TWIST1 promoter methylation level. In the PCA, Twist1 IHC expression seemed to classify cases into different groups. The DE analysis yielded 321 significant genes. In the IPA, 228 significant upstream regulators and 177 significant master regulators/causal networks were identified. In the hub gene analysis, 28 hub genes were found. The methylation level of TWIST1 promoter regions did not correlate with Twist1 protein expression. Zeb1 protein expression did not show any major correlation with global RNA expression in the PCA. Many of the observed genes and pathways associated with high Twist1 expression are known to be involved in immunoregulation, lymphocyte differentiation, and aggressive tumor biology. In conclusion, Twist1 might be an important regulator in the disease progression of MF.

Tumour Suppressor Neuron Navigator 3 and Matrix Metalloproteinase 14 are Co-expressed in Most Melanomas but Downregulated in Thick Tumours.

Melanoma is a highly metastatic tumour originating from neural crest-derived melanocytes. The aim of this study was to analyse the expression of neuron navigator 3 (NAV3) in relation to membrane type-1 matrix metalloproteinase MMP14, a major regulator of invasion, in 40 primary melanomas, 15 benign naevi and 2 melanoma cell lines. NAV3 copy number changes were found in 18/27 (67%) primary melanomas, so that deletions dominated (16/27 of samples, 59%). NAV3 protein was found to be localized at the leading edge of migrating melanoma cells in vitro. Silencing of NAV3 reduced both melanoma cell migration in 2-dimensional conditions, as well as sprouting in 3-dimensional collagen I. NAV3 protein expression correlated with MMP14 in 26/37 (70%) primary melanomas. NAV3 and MMP14 were co-expressed in all tumours with Breslow thickness < 1 mm, in 11/23 of mid-thickness tumours (1-5 mm), but in only 1/6 samples of thick (> 5 mm) melanomas. Altogether, NAV3 number changes are frequent in melanomas, and NAV3 and MMP14, while expressed in all thin melanomas, are often downregulated in thicker tumours, suggesting that the lack of both NAV3 and MMP14 favours melanoma progression.

Hyperspectral Imaging for Non-invasive Diagnostics of Melanocytic Lesions.

Malignant melanoma poses a clinical diagnostic problem, since a large number of benign lesions are excised to find a single melanoma. This study assessed the accuracy of a novel non-invasive diagnostic technology, hyperspectral imaging, for melanoma detection. Lesions were imaged prior to excision and histopathological analysis. A deep neural network algorithm was trained twice to distinguish between histopathologically verified malignant and benign melanocytic lesions and to classify the separate subgroups. Furthermore, 2 different approaches were used: a majority vote classification and a pixel-wise classification. The study included 325 lesions from 285 patients. Of these, 74 were invasive melanoma, 88 melanoma in situ, 115 dysplastic naevi, and 48 non-dysplastic naevi. The study included a training set of 358,800 pixels and a validation set of 7,313 pixels, which was then tested with a training set of 24,375 pixels. The majority vote classification achieved high overall sensitivity of 95% and a specificity of 92% (95% confidence interval (95% CI) 0.024-0.029) in differentiating malignant from benign lesions. In the pixel-wise classification, the overall sensitivity and specificity were both 82% (95% CI 0.005-0.005). When divided into 4 subgroups, the diagnostic accuracy was lower. Hyperspectral imaging provides high sensitivity and specificity in distinguishing between naevi and melanoma. This novel method still needs further validation.

FPI Based Hyperspectral Imager for the Complex Surfaces-Calibration, Illumination and Applications.

Hyperspectral imaging (HSI) applications for biomedical imaging and dermatological applications have been recently under research interest. Medical HSI applications are non-invasive methods with high spatial and spectral resolution. HS imaging can be used to delineate malignant tumours, detect invasions, and classify lesion types. Typical challenges of these applications relate to complex skin surfaces, leaving some skin areas unreachable. In this study, we introduce a novel spectral imaging concept and conduct a clinical pre-test, the findings of which can be used to develop the concept towards a clinical application. The SICSURFIS spectral imager concept combines a piezo-actuated Fabry-Pérot interferometer (FPI) based hyperspectral imager, a specially designed LED module and several sizes of stray light protection cones for reaching and adapting to the complex skin surfaces. The imager is designed for the needs of photometric stereo imaging for providing the skin surface models (3D) for each captured wavelength. The captured HS images contained 33 selected wavelengths (ranging from 477 nm to 891 nm), which were captured simultaneously with accordingly selected LEDs and three specific angles of light. The pre-test results show that the data collected with the new SICSURFIS imager enable the use of the spectral and spatial domains with surface model information. The imager can reach complex skin surfaces. Healthy skin, basal cell carcinomas and intradermal nevi lesions were classified and delineated pixel-wise with promising results, but further studies are needed. The results were obtained with a convolutional neural network.

Differentiating Malignant from Benign Pigmented or Non-Pigmented Skin Tumours-A Pilot Study on 3D Hyperspectral Imaging of Complex Skin Surfaces and Convolutional Neural Networks.

Several optical imaging techniques have been developed to ease the burden of skin cancer disease on our health care system. Hyperspectral images can be used to identify biological tissues by their diffuse reflected spectra. In this second part of a three-phase pilot study, we used a novel hand-held SICSURFIS Spectral Imager with an adaptable field of view and target-wise selectable wavelength channels to provide detailed spectral and spatial data for lesions on complex surfaces. The hyperspectral images (33 wavelengths, 477-891 nm) provided photometric data through individually controlled illumination modules, enabling convolutional networks to utilise spectral, spatial, and skin-surface models for the analyses. In total, 42 lesions were studied: 7 melanomas, 13 pigmented and 7 intradermal nevi, 10 basal cell carcinomas, and 5 squamous cell carcinomas. All lesions were excised for histological analyses. A pixel-wise analysis provided map-like images and classified pigmented lesions with a sensitivity of 87% and a specificity of 93%, and 79% and 91%, respectively, for non-pigmented lesions. A majority voting analysis, which provided the most probable lesion diagnosis, diagnosed 41 of 42 lesions correctly. This pilot study indicates that our non-invasive hyperspectral imaging system, which involves shape and depth data analysed by convolutional neural networks, is feasible for differentiating between malignant and benign pigmented and non-pigmented skin tumours, even on complex skin surfaces.

Clinical, histopathological and prognostic features of primary cutaneous acral CD8+ T-cell lymphoma and other dermal CD8+ cutaneous lymphoproliferations: results of an EORTC Cutaneous Lymphoma Group workshop.

BACKGROUND: The differential diagnosis of atypical dermal nonepidermotropic CD8+ lymphocytic infiltrates includes a heterogeneous spectrum of lymphoproliferations with overlapping histological and phenotypic features, but divergent clinical manifestations and prognoses. As these neoplasms are rare, more data on their clinicopathological presentation and course are needed. OBJECTIVES: To assess the clinical, histological and immunophenotypic features; outcomes of; and differences between dermal CD8+ lymphoproliferations. METHODS: Retrospective analysis of a series of 46 patients and biopsies by the international EORTC Cutaneous Lymphoma Group. RESULTS: The dermal CD8+ lymphoproliferations (n = 46) could be assigned to one of three groups: (i) cutaneous acral CD8+ T-cell lymphoma (n = 31), characterized mostly by a solitary nodule arising at acral sites, a monotonous dermal infiltrate of small-to-medium-sized CD8+ lymphocytes with a characteristic dot-like pattern of CD68, a low proliferation rate and an excellent prognosis; (ii) primary cutaneous CD8+ peripheral T-cell lymphoma, unspecified/NOS (n = 11), presenting with one or multiple rapidly evolving tumours, mostly medium-sized pleomorphic CD8+ tumour cells with expression of several cytotoxic markers, and high proliferative activity; and (iii) cutaneous CD8+ lymphoproliferations (n = 4), associated with congenital immunodeficiency syndromes in two patients with persisting localized or disseminated violaceous to brownish plaques on the extremities, a histiocyte-rich infiltrate of mostly small CD8+ lymphocytes with subtle atypia and a protracted course; and papular CD8+ eruptions in two patients with acquired immunosuppression. CONCLUSIONS: A constellation of distinct clinical, histopathological and phenotypic features allows discrimination and assignment of dermal CD8+ infiltrates into distinct disease entities. Primary cutaneous acral CD8+ lymphoma, assigned a provisional category in current lymphoma classifications, is a distinct and reproducible entity. A correct diagnosis is essential to avoid unnecessarily aggressive treatment for indolent CD8+ lymphoproliferations and to identify cases with underlying immuno-deficiency or potential for dismal outcome.

Assessment of Treatment Approaches and Outcomes in Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis: Insights From a Pan-European Multicenter Study.

IMPORTANCE: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe drug reactions associated with a high rate of mortality and morbidity. There is no consensus on the treatment strategy. OBJECTIVE: To explore treatment approaches across Europe and outcomes associated with the SJS/TEN disease course, as well as risk factors and culprit drugs. DESIGN, SETTING, AND PARTICIPANTS: A retrospective pan-European multicenter cohort study including 13 referral centers belonging to the ToxiTEN ERN-skin subgroup was conducted. A total of 212 adults with SJS/TEN were included between January 1, 2015, and December 31, 2019, and data were collected from a follow-up period of 6 weeks. MAIN OUTCOMES AND MEASURES: Risk factors for severe acute-phase complications (acute kidney failure, septicemia, and need for mechanical ventilation) and mortality 6 weeks following admission were evaluated using a multivariable-adjusted logistic regression model. One tool used in evaluation of severity was the Score of Toxic Epidermal Necrolysis (SCORTEN), which ranges from 0 to 7, with 7 the highest level of severity. RESULTS: Of 212 patients (134 of 211 [63.7%] women; mean [SD] age, 51.0 [19.3] years), the mean (SD) body surface area detachment was 27% (32.8%). In 176 (83.0%) patients, a culprit drug was identified. Antibiotics (21.2%), followed by anticonvulsants (18.9%), nonsteroidal anti-inflammatory drugs (11.8%), allopurinol (11.3%), and sulfonamides (10.4%), were the most common suspected agents. Treatment approaches ranged from best supportive care only (38.2%) to systemic glucocorticoids (35.4%), intravenous immunoglobulins (23.6%), cyclosporine (10.4%), and antitumor necrosis factor agents (3.3%). Most patients (63.7%) developed severe acute-phase complications. The 6-week mortality rate was 20.8%. Maximal body surface area detachment (≥30%) was found to be independently associated with severe acute-phase complications (fully adjusted odds ratio [OR], 2.49; 95% CI, 1.21-5.12; P = .01) and SCORTEN greater than or equal to 2 was significantly associated with mortality (fully adjusted OR, 10.30; 95% CI, 3.82-27.78; P < .001). Cyclosporine was associated with a higher frequency of greater than or equal to 20% increase in body surface area detachment in the acute phase (adjusted OR, 3.44; 95% CI, 1.12-10.52; P = .03) and an increased risk of infections (adjusted OR, 7.16; 95% CI, 1.52-33.74; P = .01). Systemic glucocorticoids and intravenous immunoglobulins were associated with a decreased risk of infections (adjusted OR, 0.40; 95% CI, 0.18-0.88; P = .02). No significant difference in 6-week mortality was found between treatment groups. CONCLUSIONS AND RELEVANCE: This cohort study noted differences in treatment strategies for SJS/TEN in Europe; the findings suggest the need for prospective therapeutic studies to be conducted and registries to be developed.

Cancer Alters the Metabolic Fingerprint of Extracellular Vesicles.

Cancer alters cell metabolism. How these changes are manifested in the metabolite cargo of cancer-derived extracellular vesicles (EVs) remains poorly understood. To explore these changes, EVs from prostate, cutaneous T-cell lymphoma (CTCL), colon cancer cell lines, and control EVs from their noncancerous counterparts were isolated by differential ultracentrifugation and analyzed by nanoparticle tracking analysis (NTA), electron microscopy (EM), Western blotting, and liquid chromatography-mass spectrometry (LC-MS). Although minor differences between the cancerous and non-cancerous cell-derived EVs were observed by NTA and Western blotting, the largest differences were detected in their metabolite cargo. Compared to EVs from noncancerous cells, cancer EVs contained elevated levels of soluble metabolites, e.g., amino acids and B vitamins. Two metabolites, proline and succinate, were elevated in the EV samples of all three cancer types. In addition, folate and creatinine were elevated in the EVs from prostate and CTCL cancer cell lines. In conclusion, we present the first evidence in vitro that the altered metabolism of different cancer cells is reflected in common metabolite changes in their EVs. These results warrant further studies on the significance and usability of this metabolic fingerprint in cancer.

Novel TMEM173 Mutation and the Role of Disease Modifying Alleles.

Upon binding to pathogen or self-derived cytosolic nucleic acids cyclic GMP-AMP synthase (cGAS) triggers the production of cGAMP that further activates transmembrane protein STING. Upon activation STING translocates from ER via Golgi to vesicles. Monogenic STING gain-of-function mutations cause early-onset type I interferonopathy, with disease presentation ranging from fatal vasculopathy to mild chilblain lupus. Molecular mechanisms underlying the variable phenotype-genotype correlation are presently unclear. Here, we report a novel gain-of-function G207E STING mutation causing a distinct phenotype with alopecia, photosensitivity, thyroid dysfunction, and features of STING-associated vasculopathy with onset in infancy (SAVI), such as livedo reticularis, skin vasculitis, nasal septum perforation, facial erythema, and bacterial infections. Polymorphism in TMEM173 and IFIH1 showed variable penetrance in the affected family, implying contribution to varying phenotype spectrum. The G207E mutation constitutively activates inflammation-related pathways in vitro, and causes aberrant interferon signature and inflammasome activation in patient PBMCs. Treatment with Janus kinase 1 and 2 (JAK1/2) inhibitor baricitinib was beneficiary for a vasculitic ulcer, induced hair regrowth and improved overall well-being in one patient. Protein-protein interactions propose impaired cellular trafficking of G207E mutant. These findings reveal the molecular landscape of STING and propose common polymorphisms in TMEM173 and IFIH1 as likely modifiers of the phenotype.

Gain-of-function CEBPE mutation causes noncanonical autoinflammatory inflammasomopathy.

BACKGROUND: CCAAT enhancer-binding protein epsilon (C/EBPε) is a transcription factor involved in late myeloid lineage differentiation and cellular function. The only previously known disorder linked to C/EBPε is autosomal recessive neutrophil-specific granule deficiency leading to severely impaired neutrophil function and early mortality. OBJECTIVE: The aim of this study was to molecularly characterize the effects of C/EBPε transcription factor Arg219His mutation identified in a Finnish family with previously genetically uncharacterized autoinflammatory and immunodeficiency syndrome. METHODS: Genetic analysis, proteomics, genome-wide transcriptional profiling by means of RNA-sequencing, chromatin immunoprecipitation (ChIP) sequencing, and assessment of the inflammasome function of primary macrophages were performed. RESULTS: Studies revealed a novel mechanism of genome-wide gain-of-function that dysregulated transcription of 464 genes. Mechanisms involved dysregulated noncanonical inflammasome activation caused by decreased association with transcriptional repressors, leading to increased chromatin occupancy and considerable changes in transcriptional activity, including increased expression of NLR family, pyrin domain-containing 3 protein (NLRP3) and constitutively expressed caspase-5 in macrophages. CONCLUSION: We describe a novel autoinflammatory disease with defective neutrophil function caused by a homozygous Arg219His mutation in the transcription factor C/EBPε. Mutated C/EBPε acts as a regulator of both the inflammasome and interferome, and the Arg219His mutation causes the first human monogenic neomorphic and noncanonical inflammasomopathy/immunodeficiency. The mechanism, including widely dysregulated transcription, is likely not unique for C/EBPε. Similar multiomics approaches should also be used in studying other transcription factor-associated diseases.