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1.
Am J Dermatopathol ; 2024 Apr 23.
Article En | MEDLINE | ID: mdl-38648032

ABSTRACT: Apocrine hidrocystomas are benign, cystic neoplastic lesions resulting from the apocrine secretory component of the sweat gland. They most commonly occur on the head and neck, with predilection to the periorbital area. Less frequent sites include the axilla, nipple, external auditory canal, foreskin, conjunctiva, lower lip, and fingers, among others. The authors report a unique case of a nail bed hidrocystoma in a 55-year-old woman, a site not previously described.

2.
Front Endocrinol (Lausanne) ; 14: 1270325, 2023.
Article En | MEDLINE | ID: mdl-37867531

The hyperexpression of human leukocyte antigen class I (HLA-I) molecules on pancreatic beta-cells is widely accepted as a hallmark feature of type 1 diabetes pathogenesis. This response is important clinically since it may increase the visibility of beta-cells to autoreactive CD8+ T-cells, thereby accelerating disease progression. In this review, key factors which drive HLA-I hyperexpression will be explored, and their clinical significance examined. It is established that the presence of residual beta-cells is essential for HLA-I hyperexpression by islet cells at all stages of the disease. We suggest that the most likely drivers of this process are interferons released from beta-cells (type I or III interferon; possibly in response to viral infection) or those elaborated from influent, autoreactive immune cells (type II interferon). In both cases, Janus Kinase/Signal Transducer and Activator of Transcription (JAK/STAT) pathways will be activated to induce the downstream expression of interferon stimulated genes. A variety of models have highlighted that HLA-I expression is enhanced in beta-cells in response to interferons, and that STAT1, STAT2 and interferon regulatory factor 9 (IRF9) play key roles in mediating these effects (depending on the species of interferon involved). Importantly, STAT1 expression is elevated in the beta-cells of donors with recent-onset type I diabetes, and this correlates with HLA-I hyperexpression on an islet-by-islet basis. These responses can be replicated in vitro, and we consider that chronically elevated STAT1 may have a role in maintaining HLA-I hyperexpression. However, other data have highlighted that STAT2-IRF9 may also be critical to this process. Thus, a better understanding of how these factors regulate HLA-I under chronically stimulated conditions needs to be gathered. Finally, JAK inhibitors can target interferon signaling pathways to diminish HLA-I expression in mouse models. It seems probable that these agents may also be effective in patients; diminishing HLA-I hyperexpression on islets, reducing the visibility of beta-cells to the immune system and ultimately slowing disease progression. The first clinical trials of selective JAK inhibitors are underway, and the outcomes should have important implications for type 1 diabetes clinical management.


Diabetes Mellitus, Type 1 , Janus Kinase Inhibitors , Animals , Mice , Humans , Interferons , Diabetes Mellitus, Type 1/pathology , Janus Kinases/metabolism , Disease Progression
3.
J Am Acad Dermatol ; 89(5): e201-e202, 2023 Nov.
Article En | MEDLINE | ID: mdl-34437988
5.
Front Endocrinol (Lausanne) ; 13: 881997, 2022.
Article En | MEDLINE | ID: mdl-35957810

Aims/hypothesis: The Diabetes Virus Detection (DiViD) study has suggested the presence of low-grade enteroviral infection in pancreatic tissue collected from six of six live adult patients newly diagnosed with type 1 diabetes. The present study aimed to compare the gene and protein expression of selected virally induced pathogen recognition receptors and interferon stimulated genes in islets from these newly diagnosed type 1 diabetes (DiViD) subjects vs age-matched non-diabetic (ND) controls. Methods: RNA was extracted from laser-captured islets and Affymetrix Human Gene 2.0 ST arrays used to obtain gene expression profiles. Lists of differentially expressed genes were subjected to a data-mining pipeline searching for enrichment of canonical pathways, KEGG pathways, Gene Ontologies, transcription factor binding sites and other upstream regulators. In addition, the presence and localisation of specific viral response proteins (PKR, MxA and MDA5) were examined by combined immunofluorescent labelling in sections of pancreatic tissue. Results: The data analysis and data mining process revealed a significant enrichment of gene ontologies covering viral reproduction and infectious cycles; peptide translation, elongation and initiation, as well as oxidoreductase activity. Enrichment was identified in the KEGG pathways for oxidative phosphorylation; ribosomal and metabolic activity; antigen processing and presentation and in canonical pathways for mitochondrial dysfunction, oxidative phosphorylation and EIF2 signaling. Protein Kinase R (PKR) expression did not differ between newly diagnosed type 1 diabetes and ND islets at the level of total RNA, but a small subset of ß-cells displayed markedly increased PKR protein levels. These PKR+ ß-cells correspond to those previously shown to contain the viral protein, VP1. RNA encoding MDA5 was increased significantly in newly diagnosed type 1 diabetes islets, and immunostaining of MDA5 protein was seen in α- and certain ß-cells in both newly diagnosed type 1 diabetes and ND islets, but the expression was increased in ß-cells in type 1 diabetes. In addition, an uncharacterised subset of synaptophysin positive, but islet hormone negative, cells expressed intense MDA5 staining and these were more prevalent in DiViD cases. MxA RNA was upregulated in newly diagnosed type 1 diabetes vs ND islets and MxA protein was detected exclusively in newly diagnosed type 1 diabetes ß-cells. Conclusion/interpretation: The gene expression signatures reveal that pathways associated with cellular stress and increased immunological activity are enhanced in islets from newly diagnosed type 1 diabetes patients compared to controls. The increases in viral response proteins seen in ß-cells in newly diagnosed type 1 diabetes provide clear evidence for the activation of IFN signalling pathways. As such, these data strengthen the hypothesis that an enteroviral infection of islet ß-cells contributes to the pathogenesis of type 1 diabetes.


Diabetes Mellitus, Type 1 , Insulin-Secreting Cells , Islets of Langerhans , Adult , Antiviral Agents , Diabetes Mellitus, Type 1/metabolism , Humans , Insulin-Secreting Cells/metabolism , Islets of Langerhans/metabolism , RNA
6.
Ann Palliat Med ; 11(10): 3337-3340, 2022 Oct.
Article En | MEDLINE | ID: mdl-35542971

BACKGROUND: Cutaneous squamous cell carcinoma (cSCC) is a common malignancy affecting the skin, and its incidence increases with age; as such, it disproportionately affects the elderly. It is especially difficult to treat advanced skin cancers in elderly patients with dementia, who may not tolerate radiotherapy. CASE DESCRIPTION: A 100-year-old woman with advanced dementia was referred to dermatology for a large cSCC involving the nasal bridge and abutting the bilateral orbits. She was initially deemed a poor candidate for surgical resection, but over time the tumor grew and became increasingly destructive. Due to tumor growth causing symptoms and threatening vision, her family requested treatment. The patient was therefore referred to radiation oncology, and she received palliative radiation, using a single fraction of 16 gray (Gy) via a single electron field. Within 3 months, she had a clinical complete response, with no residual tumor and no persistent side effects from radiotherapy (RT). Ongoing follow-up revealed durable treatment response with no bothersome late toxicity. CONCLUSIONS: Single-fraction palliative radiotherapy is a suitable treatment option for durable palliation in elderly patients unable to undergo surgery and unable to tolerate conventional, fractionated RT in cases of symptomatic or rapidly-progressing non-melanoma skin cancers (NMSC). It is well-tolerated in frail patients or those with dementia.


Carcinoma, Squamous Cell , Dementia , Radiation Oncology , Skin Neoplasms , Humans , Female , Aged , Aged, 80 and over , Carcinoma, Squamous Cell/radiotherapy , Carcinoma, Squamous Cell/pathology , Skin Neoplasms/radiotherapy , Palliative Care
7.
J Mol Endocrinol ; 69(2): 299-313, 2022 05 19.
Article En | MEDLINE | ID: mdl-35521765

During the development of type 1 diabetes, interferons (IFN) are elaborated from islet-infiltrating immune cells and/or from virally infected ß-cells. They act via specific receptors to increase, acutely, the phosphorylation of the transcription factors STAT1 and 2. However, the longer-term impacts of chronic IFN stimulation are poorly understood and were investigated in the current study. Human EndoC-ßH1 cells were treated with IFNα, IFNγ or IFNλ either acutely (<2 h) or chronically (≥24 h) and STAT phosphorylation, expression and activity were assessed by Western blotting and transcriptional reporter assays. Exposure of ß-cells to IFNα or IFNλ induced a swift increase in the phosphorylation of both STAT1 and STAT2, whereas IFNγ increased only pSTAT1. Over more extended periods (≥24 h), STAT phosphorylation declined but STAT1 and STAT2 expression were enhanced in a sustained manner. All IFNs stimulated ISRE transcriptional activity (but with different time courses), whereas GAS activity was responsive only to IFNγ. The re-addition of a second bolus of IFNα, 24 h after an initial dose, failed to cause renewed STAT1/2 phosphorylation. By contrast, when IFNγ was added 24 h after exposure to IFNα, rapid STAT1 phosphorylation was re-initiated. Exposure of ß-cells to IFNs leads to rapid, transient, STAT phosphorylation and to slower and more sustained increases in total STAT1/2 levels. The initial phosphorylation response is accompanied by marked desensitisation to the cognate agonist. Together, the results reveal that the response of ß-cells to IFNs is regulated both temporally and quantitatively to achieve effective signal integration.


Interferon-gamma , Interferons , Humans , Interferon-gamma/pharmacology , Interferons/metabolism , Phosphorylation
8.
J Am Acad Dermatol ; 86(1): 131-139, 2022 01.
Article En | MEDLINE | ID: mdl-34499990

BACKGROUND: Evidence is controversial and limited concerning whether surgical delays are associated with tumor growth for cutaneous squamous cell carcinomas (SCCs) and basal cell carcinomas. OBJECTIVE: Identify tumor subpopulations that may demonstrate an association between tumor growth and surgical delay. METHODS: We retrospectively analyzed 299 SCCs and 802 basal cell carcinomas treated with Mohs surgery at a single institution. Time interval from biopsy to surgery represented surgical delay. Change in major diameter (ΔMD) from size at biopsy to postoperative defect represented tumor growth. Independent predictors of ΔMD were identified by multivariate analysis. Linear regression was then utilized to assess for whether the ΔMD from these independent predictors trended with surgical delay. RESULTS: Surgical delays ranged from 0 to 331 days. Among SCCs, histologic subtype and prior treatment were identified as independent predictors of ΔMD. Significant associations between ΔMD and surgical delay were found for poorly- and moderately-differentiated SCCs, demonstrating growth rates of 0.28 cm and 0.24 cm per month of delay, respectively. The ΔMD for SCCs with prior treatment and basal cell carcinoma subgroups did not vary with surgical delay. LIMITATIONS: Retrospective design, single center. CONCLUSION: Surgical delays of less than a year were associated with tumor growth for higher-grade SCCs, with effect sizes bearing potential for clinical significance.


Carcinoma, Basal Cell , Carcinoma, Squamous Cell , Skin Neoplasms , Carcinoma, Basal Cell/pathology , Carcinoma, Basal Cell/surgery , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/surgery , Humans , Mohs Surgery , Retrospective Studies , Skin Neoplasms/pathology , Skin Neoplasms/surgery
11.
Diabet Med ; 38(12): e14724, 2021 12.
Article En | MEDLINE | ID: mdl-34654058

AIMS: We are studying the dialogue between ß-cells and the immune system in type 1 diabetes and have identified a cell surface receptor, signal regulatory protein-alpha (SIRPα) as an important component in the regulation of ß-cell survival. SIRPα interacts with another protein, CD47, to mediate signalling. In the present work, we have studied the expression and role of CD47 in human islet cells in type 1 diabetes. METHODS: Clonal EndoC-ßH1 cells were employed for functional studies. Cells were exposed to pro-inflammatory cytokines and their viability monitored by flow cytometry after staining with propidium iodide. Targeted knockdown of CD47 or SIRPα was achieved with small interference RNA molecules and the expression of relevant proteins studied by Western blotting or immunocytochemistry. Human pancreas sections were selected from the Exeter Archival Diabetes Biobank and used to examine the expression of CD47 by immunofluorescence labelling. Image analysis was employed to quantify expression. RESULTS: CD47 is abundantly expressed in both α and ß cells in human pancreas. In type 1 diabetes, the levels of CD47 are increased in α cells across all age groups, whereas the expression in ß-cells varies according to disease endotype. Knockdown of either CD47 or SIRPα in EndoC-ßH1 cells resulted in a loss of viability. CONCLUSIONS: We conclude that the CD47 plays a previously unrecognised role in the regulation of ß-cell viability. This system is dysregulated in type 1 diabetes suggesting that it may be targeted therapeutically to slow disease progression.


CD47 Antigen/genetics , Diabetes Mellitus, Type 1/genetics , Gene Expression Regulation , Insulin-Secreting Cells/metabolism , RNA/genetics , CD47 Antigen/biosynthesis , Diabetes Mellitus, Type 1/metabolism , Humans , Signal Transduction
12.
Sci Rep ; 11(1): 15624, 2021 08 02.
Article En | MEDLINE | ID: mdl-34341375

The generation of a human pancreatic beta cell line which reproduces the responses seen in primary beta cells, but is amenable to propagation in culture, has long been an important goal in diabetes research. This is particularly true for studies focussing on the role of enteroviral infection as a potential cause of beta-cell autoimmunity in type 1 diabetes. In the present work we made use of a clonal beta cell line (1.1B4) available from the European Collection of Authenticated Cell Cultures, which had been generated by the fusion of primary human beta-cells with a pancreatic ductal carcinoma cell, PANC-1. Our goal was to study the factors allowing the development and persistence of a chronic enteroviral infection in human beta-cells. Since PANC-1 cells have been reported to support persistent enteroviral infection, the hybrid 1.1B4 cells appeared to offer an ideal vehicle for our studies. In support of this, infection of the cells with a Coxsackie virus isolated originally from the pancreas of a child with type 1 diabetes, CVB4.E2, at a low multiplicity of infection, resulted in the development of a state of persistent infection. Investigation of the molecular mechanisms suggested that this response was facilitated by a number of unexpected outcomes including an apparent failure of the cells to up-regulate certain anti-viral response gene products in response to interferons. However, more detailed exploration revealed that this lack of response was restricted to molecular targets that were either activated by, or detected with, human-selective reagents. By contrast, and to our surprise, the cells were much more responsive to rodent-selective reagents. Using multiple approaches, we then established that populations of 1.1B4 cells are not homogeneous but that they contain a mixture of rodent and human cells. This was true both of our own cell stocks and those held by the European Collection of Authenticated Cell Cultures. In view of this unexpected finding, we developed a strategy to harvest, isolate and expand single cell clones from the heterogeneous population, which allowed us to establish colonies of 1.1B4 cells that were uniquely human (h1.1.B4). However, extensive analysis of the gene expression profiles, immunoreactive insulin content, regulated secretory pathways and the electrophysiological properties of these cells demonstrated that they did not retain the principal characteristics expected of human beta cells. Our data suggest that stocks of 1.1B4 cells should be evaluated carefully prior to their use as a model human beta-cell since they may not retain the phenotype expected of human beta-cells.


Insulin-Secreting Cells , Insulin , Apoptosis , Cell Line , Enterovirus Infections , Humans
15.
Case Rep Oncol Med ; 2020: 8880202, 2020.
Article En | MEDLINE | ID: mdl-32665870

Malignant gastrointestinal neuroectodermal tumor (GNET) is a rare disease with a handful of cases described in literature. GNET has only become a well-known/widely accepted entity in the recent years, but it is still not listed in the database of rare diseases. Due to the rarity of disease, there are no guidelines on standard therapeutic approaches in the adjuvant or metastatic setting. Here, we describe a unique case of GNET with a 7-year disease-free survival following adjuvant cisplatin and etoposide chemotherapy. This is the longest disease-free survival that has ever been described in literature and may support using this combination in a larger cohort of patients in the context of a global clinical trial. We will also review the histopathologic features of GNET and potential therapeutic options in the metastatic setting.

16.
Nat Commun ; 11(1): 2584, 2020 05 22.
Article En | MEDLINE | ID: mdl-32444635

Interferon-α (IFNα), a type I interferon, is expressed in the islets of type 1 diabetic individuals, and its expression and signaling are regulated by T1D genetic risk variants and viral infections associated with T1D. We presently characterize human beta cell responses to IFNα by combining ATAC-seq, RNA-seq and proteomics assays. The initial response to IFNα is characterized by chromatin remodeling, followed by changes in transcriptional and translational regulation. IFNα induces changes in alternative splicing (AS) and first exon usage, increasing the diversity of transcripts expressed by the beta cells. This, combined with changes observed on protein modification/degradation, ER stress and MHC class I, may expand antigens presented by beta cells to the immune system. Beta cells also up-regulate the checkpoint proteins PDL1 and HLA-E that may exert a protective role against the autoimmune assault. Data mining of the present multi-omics analysis identifies two compound classes that antagonize IFNα effects on human beta cells.


Alternative Splicing , Insulin-Secreting Cells/physiology , Interferon-alpha/metabolism , Interferon-alpha/pharmacology , Alternative Splicing/drug effects , Cells, Cultured , Chromatin/drug effects , Chromatin/metabolism , Data Mining , Diabetes Mellitus, Type 1/genetics , Gene Expression Regulation/drug effects , Gene Regulatory Networks , Humans , Insulin-Secreting Cells/drug effects , Protein Interaction Maps , Proteomics , Transcription Factors/genetics , Transcription Factors/metabolism , Transcription Initiation Site
17.
Curr Diab Rep ; 19(12): 159, 2019 12 09.
Article En | MEDLINE | ID: mdl-31820163

PURPOSE OF REVIEW: Hyperexpression of classical HLA class I (HLA-I) molecules in insulin-containing islets has become a widely accepted hallmark of type 1 diabetes pathology. In comparison, relatively little is known about the expression, function and role of non-classical subtypes of HLA-I. This review focuses on the current understanding of the non-classical HLA-I subtypes: HLA-E, HLA-F and HLA-G, within and outside the field of type 1 diabetes, and considers the possible impacts of these molecules on disease etiology. RECENT FINDINGS: Evidence is growing to suggest that non-classical HLA-I proteins are upregulated, both at the RNA and protein levels in the pancreas of individuals with recent-onset type 1 diabetes. Moreover, associations between non-classical HLA-I genotypes and age at onset of type 1 diabetes have been reported in some studies. As with classical HLA-I, it is likely that hyperexpression of non-classical HLA-I is driven by the release of diffusible interferons by stressed ß cells (potentially driven by viral infection) and exacerbated by release of cytokines from infiltrating immune cells. Non-classical HLA-I proteins predominantly (but not exclusively) transduce negative signals to immune cells infiltrating at the site of injury/inflammation. We propose a model in which the islet endocrine cells, through expression of non-classical HLA-I are fighting back against the infiltrating immune cells. By inhibiting the activity and function on NK, B and select T cells, the non-classical HLA-I, proteins will reduce the non-specific bystander effects of inflammation, while at the same time still allowing the targeted destruction of ß cells by specific islet-reactive CD8+ T cells.


Diabetes Mellitus, Type 1/immunology , Histocompatibility Antigens Class I/biosynthesis , Histocompatibility Antigens Class I/immunology , Islets of Langerhans/immunology , B-Lymphocytes/immunology , CD8 Antigens/immunology , Diabetes Mellitus, Type 1/physiopathology , HLA-G Antigens/biosynthesis , Humans , Inflammation/immunology , Insulin-Secreting Cells/immunology , Islets of Langerhans/physiopathology , Killer Cells, Natural/immunology , T-Lymphocytes/immunology , Up-Regulation , HLA-E Antigens
18.
Case Reports Immunol ; 2019: 1869524, 2019.
Article En | MEDLINE | ID: mdl-31737384

We present the case of a 19-year-old female with a mild form of Autosomal Dominant Hyper IgE syndrome (HIES) associated with a loss-of-function mutation in STAT3. Within the first years of life she developed multiple, Staphylococcus aureus associated abscesses in the neck and face requiring frequent incision and drainage. Respiratory tract infections were not a feature of the clinical phenotype and a high resolution thoracic CT scan was unremarkable. Retained dentition was noted but fungal nail disease and recurrent thrush were absent. The total IgE was 970 IU/L, Lymphocyte counts and immunoglobulin levels were normal (IgG borderline 18.5 gr/L). There was suboptimal response to test immunisation with Pneumovax II vaccine. Th17 cell phenotyping revealed low levels of IL-17 expressing cells (0.3% of total CD4 T Cells numbers). Genetic analysis identified a missense mutation, N567D, in a conserved region of the linker domain of STAT3. Functional studies in HEK293 cells reveal that this mutation potently inhibits STAT3 activity when compared to the wildtype protein. This is consistent with other reported mutations in STAT3 associated with HIES. However, surprisingly, the magnitude of inhibition was similar to another STAT3 mutation (V637M) which causes a much more severe form of the disease.

20.
Nutrients ; 11(3)2019 Mar 12.
Article En | MEDLINE | ID: mdl-30871106

Low birth weight is a risk factor for gestational and type 2 diabetes (T2D). Since mammalian target of rapamycin (mTOR) controls pancreatic ß-cell mass and hormone release, we hypothesized that nutritional insult in utero might permanently alter mTOR signaling. Mice were fed a low-protein (LP, 8%) or control (C, 20%) diet throughout pregnancy, and offspring examined until 130 days age. Mice receiving LP were born 12% smaller and ß-cell mass was significantly reduced throughout life. Islet mTOR levels were lower in LP-exposed mice and localized predominantly to α-rather than ß-cells. Incubation of isolated mouse islets with rapamycin significantly reduced cell proliferation while increasing apoptosis. mRNA levels for mTORC complex genes mTOR, Rictor and Raptor were elevated at 7 days in LP mice, as were the mTOR and Raptor proteins. Proglucagon gene expression was similarly increased, but not insulin or the immune/metabolic defense protein STING. In human and mouse pancreas STING was strongly associated with islet ß-cells. Results support long-term changes in islet mTOR signaling in response to nutritional insult in utero, with altered expression of glucagon and insulin and a reduced ß-cell mass. This may contribute to an increased risk of gestational or type 2 diabetes.


Diet, Protein-Restricted , Dietary Proteins/administration & dosage , Glucagon/metabolism , Islets of Langerhans/drug effects , Prenatal Nutritional Physiological Phenomena , TOR Serine-Threonine Kinases/metabolism , Animals , Cell Line , Female , Gene Expression Regulation/drug effects , Glucagon/genetics , Insulin/genetics , Insulin/metabolism , Islets of Langerhans/cytology , Islets of Langerhans/metabolism , Mice , Mice, Inbred BALB C , Pregnancy , Random Allocation , TOR Serine-Threonine Kinases/genetics
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