Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
1.
Br J Haematol ; 204(1): 292-305, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37876306

RESUMO

Shwachman-Diamond syndrome (SDS) is characterized by neutropenia, exocrine pancreatic insufficiency and skeletal abnormalities. SDS bone marrow haematopoietic progenitors show increased apoptosis and impairment in granulocytic differentiation. Loss of Shwachman-Bodian-Diamond syndrome (SBDS) expression results in reduced eukaryotic 80S ribosome maturation. Biallelic mutations in the SBDS gene are found in ~90% of SDS patients, ~55% of whom carry the c.183-184TA>CT nonsense mutation. Several translational readthrough-inducing drugs aimed at suppressing nonsense mutations have been developed. One of these, ataluren, has received approval in Europe for the treatment of Duchenne muscular dystrophy. We previously showed that ataluren can restore full-length SBDS protein synthesis in SDS-derived bone marrow cells. Here, we extend our preclinical study to assess the functional restoration of SBDS capabilities in vitro and ex vivo. Ataluren improved 80S ribosome assembly and total protein synthesis in SDS-derived cells, restored myelopoiesis in myeloid progenitors, improved neutrophil chemotaxis in vitro and reduced neutrophil dysplastic markers ex vivo. Ataluren also restored full-length SBDS synthesis in primary osteoblasts, suggesting that its beneficial role may go beyond the myeloid compartment. Altogether, our results strengthened the rationale for a Phase I/II clinical trial of ataluren in SDS patients who harbour the nonsense mutation.


Assuntos
Doenças da Medula Óssea , Insuficiência Pancreática Exócrina , Lipomatose , Humanos , Síndrome de Shwachman-Diamond , Proteína Supressora de Tumor p53/genética , Lipomatose/genética , Códon sem Sentido , Mielopoese , Neutrófilos/metabolismo , Quimiotaxia , Doenças da Medula Óssea/genética , Doenças da Medula Óssea/terapia , Insuficiência Pancreática Exócrina/genética , Ribossomos/metabolismo
2.
Ocul Immunol Inflamm ; : 1-6, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37797183

RESUMO

PURPOSE: To evaluate the efficacy of systemic tumor necrosis factor-alpha inhibitors (TNFi) in the treatment of non-infectious uveitis (NIU). METHODS: This Swiss multicenter retrospective cohort study included patients with NIU requiring TNFi during the period from 2001 to 2018. Risk factors for the occurrence of new complications were identified using Cox regression analysis and hazard ratios (HR). RESULTS: Seventy-one patients (126 eyes; mean age 40.6 ± 14.4 years, mean duration of uveitis 46.0 ± 61.8 months) were followed for 40.2 ± 17.3 months after addition of TNFi. Under TNFi, visual acuity improved from 0.2 ± 0.3 to 0.1 ± 0.3 logMAR (p < 0.001). The portion of patients under systemic corticosteroids decreased from 81.7% to 25.4% (p < 0.001), while that for conventional synthetic disease-modifying anti-rheumatic drugs insignificantly decreased from 63.4% to 50.7% (p > 0.05). In 80.2% of eyes, complications were present at baseline with epiretinal gliosis (39.7%), cataract (41.3%) and macular edema (ME; 27.8%) being the most common. New complications under TNFi were encountered in 49.2% of eyes, also including recurrence (5 eyes) or new onset of ME (14 eyes). The need for switching of TNFi was associated with further complications (HR 3.78, p = 0.012). CONCLUSION: Although the efficacy and tolerability of TNFi in a real-life setting are favorable, treatment is often initiated late, i.e., after many eyes have already developed complications. Even with TNFi, new complications, particularly ME, cannot be completely avoided. Further research is needed to assess the impact of earlier initiation of TNFi therapy.

3.
Int J Mol Sci ; 24(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36674422

RESUMO

Cystic fibrosis (CF) is characterized by a progressive decline in lung function, which may be further impaired by viral infections. CF is therefore considered a comorbidity of coronavirus disease 2019 (COVID-19), and SARS-CoV-2 vaccine prioritization has been proposed for patients with (pw)CF. Poor outcomes have been reported in lung transplant recipients (LTR) after SARS-CoV-2 infections. LTR have also displayed poor immunization against SARS-CoV-2 after mRNA-based BNT162b2 vaccination, especially in those undergoing immunosuppressive treatment, mostly those receiving mycophenolate mofetil (MMF) therapy. We aimed to determine here the immunogenicity and safety of the BNT162b2 vaccine in our cohort of 260 pwCF, including 18 LTR. Serum levels of neutralizing anti-SARS-CoV-2 IgG and IgA antibodies were quantified after the administration of two doses. PwCF displayed a vaccine-induced IgG and IgA antiviral response comparable with that seen in the general population. We also observed that the immunogenicity of the BNT162b2 vaccine was significantly impaired in the LTR subcohort, especially in patients undergoing MMF therapy. The BNT162b2 vaccine also caused minor adverse events as in the general population, mostly after administration of the second dose. Overall, our results justify the use of the BNT162b2 vaccine in pwCF and highlight the importance of a longitudinal assessment of the anti-SARS-CoV-2 IgG and IgA neutralizing antibody response to COVID-19 vaccination.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Fibrose Cística , Transplante de Pulmão , Humanos , Anticorpos Antivirais , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Fibrose Cística/complicações , Imunoglobulina A , Imunoglobulina G , Transplante de Pulmão/efeitos adversos , SARS-CoV-2
4.
Nat Commun ; 14(1): 132, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36627352

RESUMO

As an inherited disorder characterized by severe pulmonary disease, cystic fibrosis could be considered a comorbidity for coronavirus disease 2019. Instead, current clinical evidence seems to be heading in the opposite direction. To clarify whether host factors expressed by the Cystic Fibrosis epithelia may influence coronavirus disease 2019 progression, here we describe the expression of SARS-CoV-2 receptors in primary airway epithelial cells. We show that angiotensin converting enzyme 2 (ACE2) expression and localization are regulated by Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) channel. Consistently, our results indicate that dysfunctional CFTR channels alter susceptibility to SARS-CoV-2 infection, resulting in reduced viral entry and replication in Cystic Fibrosis cells. Depending on the pattern of ACE2 expression, the SARS-CoV-2 spike (S) protein induced high levels of Interleukin 6 in healthy donor-derived primary airway epithelial cells, but a very weak response in primary Cystic Fibrosis cells. Collectively, these data support that Cystic Fibrosis condition may be at least partially protecting from SARS-CoV-2 infection.


Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Fibrose Cística , SARS-CoV-2 , Internalização do Vírus , Humanos , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Regulação para Baixo , Receptores Virais/genética , Receptores Virais/metabolismo , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Replicação Viral
5.
Ocul Immunol Inflamm ; 31(5): 981-988, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35588311

RESUMO

PURPOSE: To assess the efficacy of tumor necrosis factor-alpha inhibitors (TNFi) on uveitic macular edema (ME) unresponsive to conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs). METHODS: This multicenter retrospective study included patients with uveitic ME persisting despite csDMARDs. The effect of an additional TNFi on central retinal thickness (CRT), best corrected visual acuity (BCVA) and corticosteroid need was evaluated. RESULTS: Thirty-five eyes (26 patients, mean age 42.9 ± 15.2 years) were included. CRT decreased from 425 ± 137 µm to 294 ± 66 µm (p < .001) and 280 ± 48 µm (p < .001) at 1 and 4 years of follow-up, respectively. BCVA improved from 0.28 ± 0.22 to 0.21 ± 0.48 (1 year, p = .013) and 0.08 ± 0.13 logMAR (4 years, p = .002). The proportion of patients requiring systemic corticosteroids decreased from 88.5% to 34.8% (1 year) and 15.4% (4 years). CONCLUSION: The addition of a TNFi resulted in an improvement of CRT and BCVA for up to 4 years in uveitic ME but rescue treatments were needed for some patients.


Assuntos
Edema Macular , Uveíte , Humanos , Adulto , Pessoa de Meia-Idade , Edema Macular/diagnóstico , Edema Macular/tratamento farmacológico , Edema Macular/etiologia , Fator de Necrose Tumoral alfa/uso terapêutico , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Estudos Retrospectivos , Suíça , Resultado do Tratamento , Seguimentos , Injeções Intravítreas , Uveíte/complicações , Uveíte/diagnóstico , Uveíte/tratamento farmacológico , Tomografia de Coerência Óptica
6.
Int J Mol Sci ; 23(17)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36077295

RESUMO

This study concerns the analysis of the modulation of Chronic Myeloid Leukemia (CML) cell model K562 transcriptome following transfection with the tumor suppressor gene encoding for Protein Tyrosine Phosphatase Receptor Type G (PTPRG) and treatment with the tyrosine kinase inhibitor (TKI) Imatinib. Specifically, we aimed at identifying genes whose level of expression is altered by PTPRG modulation and Imatinib concentration. Statistical tests as differential expression analysis (DEA) supported by gene set enrichment analysis (GSEA) and modern methods of ontological term analysis are presented along with some results of current interest for forthcoming experimental research in the field of the transcriptomic landscape of CML. In particular, we present two methods that differ in the order of the analysis steps. After a gene selection based on fold-change value thresholding, we applied statistical tests to select differentially expressed genes. Therefore, we applied two different methods on the set of differentially expressed genes. With the first method (Method 1), we implemented GSEA, followed by the identification of transcription factors. With the second method (Method 2), we first selected the transcription factors from the set of differentially expressed genes and implemented GSEA on this set. Method 1 is a standard method commonly used in this type of analysis, while Method 2 is unconventional and is motivated by the intention to identify transcription factors more specifically involved in biological processes relevant to the CML condition. Both methods have been equipped in ontological knowledge mining and word cloud analysis, as elements of novelty in our analytical procedure. Data analysis identified RARG and CD36 as a potential PTPRG up-regulated genes, suggesting a possible induction of cell differentiation toward an erithromyeloid phenotype. The prediction was confirmed at the mRNA and protein level, further validating the approach and identifying a new molecular mechanism of tumor suppression governed by PTPRG in a CML context.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Proteínas Tirosina Fosfatases Classe 5 Semelhantes a Receptores/genética , Resistencia a Medicamentos Antineoplásicos , Expressão Gênica , Genes Supressores de Tumor , Humanos , Mesilato de Imatinib/uso terapêutico , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Monoéster Fosfórico Hidrolases/genética , Inibidores de Proteínas Quinases/uso terapêutico , Fatores de Transcrição/genética
7.
Front Oncol ; 12: 904510, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35756686

RESUMO

Chronic myeloid leukemia (CML) is a myeloproliferative disease caused by the acquisition of t(9;22) generating the fusion tyrosine kinase BCR::ABL1. However, despite the crucial role of this protein in the dysregulation of numerous signal transduction pathways, a direct measure of BCR::ABL1 kinase activity in chronic phase (CP) CML was never accomplished due to intense degradative activity present in mature leukocytes. Therefore, we developed a procedure suitable to preserve BCR::ABL1 protein under non-denaturing, neutral pH conditions in primary, chronic phase (CP)-CML samples. As a result, specific kinase activity was detected utilizing a biotinylated peptide substrate highly selective for c-ABL1. Furthermore, through this approach, BCR::ABL1 kinase activity was barely detectable in CP-CML compared to Ph+ acute lymphoblastic leukemia primary samples, where kinase activity is comparable to those measured in Ph+ cell lines. These in vitro findings provide the first direct measure of BCR::ABL1 kinase activity in primary CP-CML and reveal the presence of a still uncharacterized inhibitory mechanism that maintains BCR::ABL1 in a low activity state in CP-CML despite its overexpression.

8.
Biomolecules ; 12(1)2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-35053232

RESUMO

Protein tyrosine phosphatase receptor gamma (PTPRG) is known to interact with and regulate several tyrosine kinases, exerting a tumor suppressor role in several type of cancers. Its wide expression in human tissues compared to the other component of group 5 of receptor phosphatases, PTPRZ expressed as a chondroitin sulfate proteoglycan in the central nervous system, has raised interest in its role as a possible regulatory switch of cell signaling processes. Indeed, a carbonic anhydrase-like domain (CAH) and a fibronectin type III domain are present in the N-terminal portion and were found to be associated with its role as [HCO3-] sensor in vascular and renal tissues and a possible interaction domain for cell adhesion, respectively. Studies on PTPRG ligands revealed the contactins family (CNTN) as possible interactors. Furthermore, the correlation of PTPRG phosphatase with inflammatory processes in different normal tissues, including cancer, and the increasing amount of its soluble form (sPTPRG) in plasma, suggest a possible role as inflammatory marker. PTPRG has important roles in human diseases; for example, neuropsychiatric and behavioral disorders and various types of cancer such as colon, ovary, lung, breast, central nervous system, and inflammatory disorders. In this review, we sum up our knowledge regarding the latest discoveries in order to appreciate PTPRG function in the various tissues and diseases, along with an interactome map of its relationship with a group of validated molecular interactors.


Assuntos
Proteínas Tirosina Fosfatases Classe 5 Semelhantes a Receptores/metabolismo , Transdução de Sinais , Proteínas Supressoras de Tumor/metabolismo , Biomarcadores/metabolismo , Adesão Celular , Humanos , Especificidade de Órgãos , Proteínas Tirosina Fosfatases Classe 5 Semelhantes a Receptores/genética , Proteínas Supressoras de Tumor/genética
9.
Swiss Med Wkly ; 152: w30049, 2022 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-35072393

RESUMO

Sarcoidosis is a systemic inflammatory disease, characterised by granuloma formation upon an unknown trigger in genetically predisposed individuals. The inflammation is characterised by an activation of both the innate immune system, with macrophages differentiating into epitheloid cells and dendritic cells, and the adaptive immune system, particularly T helper (Th) 1 and Th17 cells. Since all organs can be affected to varying extents, clinical presentation is often diverse. Most commonly, the lungs, lymph nodes, skin and eyes are involved, whereas cardiac, renal and neurological manifestations are less common but associated with higher morbidity. Depending on the clinical symptoms, a detailed evaluation including thorough clinical examination, imaging and laboratory tests should explore all possible organ involvements. In some patients, fatigue manifests as a para-sarcoidosis symptom impacting quality of life, even if sarcoidosis is in remission. Some acute syndromic presentations, such as Löfgren's syndrome, have a good prognosis and are commonly self-limiting. If possible, a topical treatment, for example for cutaneous sarcoidosis or bronchial involvement, should be applied. Treatment of severe cases with persisting disease activity necessitates long-term immunosuppressive drugs, with glucocorticoids as the first-line option. Steroid-sparing and second-line drugs include methotrexate, azathioprine, mycophenolate mofetil and immunomodulators such hydroxychloroquine, with the latter being first-line therapy in cutaneous sarcoidosis. Tumour necrosis factor-alpha inhibitors (particularly adalimumab and infliximab) are used as third-line agents but are administered earlier in cases of persistent disease activity, severe organ-involvement or intolerance to conventional drugs. Treatment decisions should be based on a multidisciplinary approach, depending on organ involvement and treatment tolerability. Para-sarcoidosis manifestations, particularly fatigue, should also be carefully addressed, where the patient could also be enrolled in multidimensional rehabilitation programmes. With various organ involvement and different phenotypes, larger studies including real-world data from registries are necessary to evaluate different sarcoidosis endotypes and preferential treatment pathways.


Assuntos
Sarcoidose Pulmonar , Sarcoidose , Azatioprina/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Qualidade de Vida , Sarcoidose/diagnóstico , Sarcoidose/tratamento farmacológico , Sarcoidose Pulmonar/tratamento farmacológico
10.
Front Pharmacol ; 12: 749361, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867354

RESUMO

The pathogenic role of the overactivated ABL1 tyrosine kinase (TK) pathway is well recognized in some forms of BCR-ABL1 like acute lymphoblastic leukemia (ALL); TK inhibitors represent a useful therapeutic choice in these patients who respond poorly to conventional chemotherapy. Here we report a novel peptide biosensor (PABL)-ELISA assay to investigate ABL1 activity in four immortalized leukemic cell lines with different genetic background. The PABL sequence comprises an ABL1 tyrosine (Y) phosphorylation site and a targeting sequence that increases the specificity for ABL1; additional peptides (Y-site-mutated (PABL-F) and fully-phosphorylated (PPHOSPHO-ABL) biosensors) were included in the assay. After incubation with whole cell lysates, average PABL phosphorylation was significantly increased (basal vs. PABL phosphorylation: 6.84 ± 1.46% vs. 32.44 ± 3.25%, p-value < 0.0001, two-way ANOVA, Bonferroni post-test, percentages relative to PPHOSPHO-ABL in each cell line). Cell lines expressing ABL1-chimeric proteins (K562, ALL-SIL) presented the higher TK activity on PABL; a lower signal was instead observed for NALM6 and REH (p < 0.001 and p < 0.05 vs. K562, respectively). Phosphorylation was ABL1-mediated, as demonstrated by the specific inhibition of imatinib (p < 0.001 for K562, NALM6, ALL-SIL and p < 0.01 for REH) in contrast to ruxolitinib (JAK2-inhibitor), and occurred on the ABL1 Y-site, as demonstrated by PABL-F whose phosphorylation was comparable to basal levels. In order to validate this novel PABL-ELISA assay on leukemic cells isolated from patient's bone marrow aspirates, preliminary analysis on blasts derived from an adult affected by chronic myeloid leukaemia (BCR-ABL1 positive) and a child affected by ALL (BCR-ABL1 negative) were performed. Phosphorylation of PABL was specifically inhibited after the incubation of BCR-ABL1 positive cell lysates with imatinib, but not with ruxolitinib. While requiring further optimization and validation in leukemic blasts to be of clinical interest, the PABL-based ELISA assay provides a novel in vitro tool for screening both the aberrant ABL1 activity in BCR-ABL1 like ALL leukemic cells and their potential response to TK inhibitors.

11.
Cancer Control ; 28: 10732748211038429, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34789006

RESUMO

OBJECTIVE: It is debatable whether BCR-ABL1 transcript type has an impact on outcome of treatment of patients with CML, and it is not widely studied whether body weight influences response to treatment. In this study, we tried to find out if any of these factors has an impact on response to treatment and outcome. METHODOLOGY: We conducted a retrospective analysis of the files of 79 patients being treated in our center for CML with known BCR-ABL1 breakpoints, and patients' management and response assessment was done based on ELN 2013 guidelines. The analysis was performed based on two main groups, obese vs. normal BMI, and then based on BCR-ABL1 transcripts: e13a2 vs. e14a2. Cumulative incidence of MMR, CCyR, and DMR were estimated using the Kaplan-Meier survival curve method, and comparisons between groups were performed by the Log-rank/Gray test methods. RESULTS/CONCLUSION: In the patient-cohort studied, there was no statistically significant difference in molecular response between patients with CML based on body weight or transcript type although patients in the obesity group achieved higher and faster MMR with no statistical significance.


Assuntos
Proteínas de Fusão bcr-abl/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/epidemiologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Obesidade/epidemiologia , Adulto , Idoso , Peso Corporal , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores Sociodemográficos , Adulto Jovem
12.
Cancers (Basel) ; 13(10)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34065882

RESUMO

Chronic myeloid leukemia (CML) is a myeloproliferative disorder characterized by BCR-ABL1 oncogene expression. This dysregulated protein-tyrosine kinase (PTK) is known as the principal driver of the disease and is targeted by tyrosine kinase inhibitors (TKIs). Extensive documentation has elucidated how the transformation of malignant cells is characterized by multiple genetic/epigenetic changes leading to the loss of tumor-suppressor genes function or proto-oncogenes expression. The impairment of adequate levels of substrates phosphorylation, thus affecting the balance PTKs and protein phosphatases (PPs), represents a well-established cellular mechanism to escape from self-limiting signals. In this review, we focus our attention on the characterization of and interactions between PTKs and PPs, emphasizing their biological roles in disease expansion, the regulation of LSCs and TKI resistance. We decided to separate those PPs that have been validated in primary cell models or leukemia mouse models from those whose studies have been performed only in cell lines (and, thus, require validation), as there may be differences in the manner that the associated pathways are modified under these two conditions. This review summarizes the roles of diverse PPs, with hope that better knowledge of the interplay among phosphatases and kinases will eventually result in a better understanding of this disease and contribute to its eradication.

13.
Front Cell Dev Biol ; 9: 768969, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35071225

RESUMO

Members of the Protein Tyrosine Phosphatase (PTPs) family are associated with growth regulation and cancer development. Acting as natural counterpart of tyrosine kinases (TKs), mainly involved in crucial signaling pathways such as regulation of cell cycle, proliferation, invasion and angiogenesis, they represent key parts of complex physiological homeostatic mechanisms. Protein tyrosine phosphatase gamma (PTPRG) is classified as a R5 of the receptor type (RPTPs) subfamily and is broadly expressed in various isoforms in different tissues. PTPRG is considered a tumor-suppressor gene (TSG) mapped on chromosome 3p14-21, a region frequently subject to loss of heterozygosity in various tumors. However, reported mechanisms of PTPRG downregulation include missense mutations, ncRNA gene regulation and epigenetic silencing by hypermethylation of CpG sites on promoter region causing loss of function of the gene product. Inactive forms or total loss of PTPRG protein have been described in sporadic and Lynch syndrome colorectal cancer, nasopharyngeal carcinoma, ovarian, breast, and lung cancers, gastric cancer or diseases affecting the hematopoietic compartment as Lymphoma and Leukemia. Noteworthy, in Central Nervous System (CNS) PTPRZ/PTPRG appears to be crucial in maintaining glioblastoma cell-related neuronal stemness, carving out a pathological functional role also in this tissue. In this review, we will summarize the current knowledge on the role of PTPRG in various human cancers.

14.
Int J Mol Sci ; 21(7)2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32225105

RESUMO

Protein tyrosine phosphatase receptor type γ (PTPRG) is a tumor suppressor gene, down-regulated in Chronic Myeloid Leukemia (CML) cells by the hypermethylation of its promoter region. ß-catenin (CTNNB1) is a critical regulator of Leukemic Stem Cells (LSC) maintenance and CML proliferation. This study aims to demonstrate the antagonistic regulation between ß-catenin and PTPRG in CML cells. The specific inhibition of PTPRG increases the activation state of BCR-ABL1 and modulates the expression of the BCR-ABL1- downstream gene ß-Catenin. PTPRG was found to be capable of dephosphorylating ß-catenin, eventually causing its cytosolic destabilization and degradation in cells expressing PTPRG. Furthermore, we demonstrated that the increased expression of ß-catenin in PTPRG-negative CML cell lines correlates with DNA (cytosine-5)-methyl transferase 1 (DNMT1) over-expression, which is responsible for PTPRG promoter hypermethylation, while its inhibition or down-regulation correlates with PTPRG re-expression. We finally confirmed the role of PTPRG in regulating BCR-ABL1 and ß-catenin phosphorylation in primary human CML samples. We describe here, for the first time, the existence of a regulative loop occurring between PTPRG and ß-catenin, whose reciprocal imbalance affects the proliferation kinetics of CML cells.


Assuntos
Regulação Neoplásica da Expressão Gênica , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Proteínas Tirosina Fosfatases Classe 5 Semelhantes a Receptores/genética , beta Catenina/genética , DNA (Citosina-5-)-Metiltransferase 1/genética , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Metilação de DNA , Regulação para Baixo , Proteínas de Fusão bcr-abl/genética , Proteínas de Fusão bcr-abl/metabolismo , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Regiões Promotoras Genéticas , Proteínas Tirosina Fosfatases Classe 5 Semelhantes a Receptores/metabolismo , Células Tumorais Cultivadas , beta Catenina/metabolismo
15.
Case Rep Ophthalmol Med ; 2019: 3849871, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31885977

RESUMO

The purpose of the study was to analyze imaging findings in spectral domain en face optical coherence tomography (SD OCT) in patients with laser-induced and solar maculopathies focusing on the possible regeneration of the ellipsoid zone. In a retrospective case series of 3 patients (4 eyes) with solar maculopathy and 2 patients (3 eyes) with laser-induced maculopathy who underwent a comprehensive ocular examination, ellipsoid zone (EZ) was segmented from SD OCT data. Evaluation of EZ in en face OCT revealed a hyporeflective lesion surrounded by a hyperreflective border. The area of EZ alteration was measured manually in en face OCT. All patients showed partial EZ regeneration. Mean EZ alteration decreased from 0.12 mm2 (range: 0.05-0.32) at baseline to 0.07 mm2 (range: 0.01-0.22) at last follow-up (p = 0.018, mean follow-up: 372 days; range: 115-592). Mean best visual acuity (BVA) improved from 20/36 at baseline to 20/30 (p = 0.018). In conclusion, en face OCT imaging clearly delineated the area of EZ alteration in patients with laser-induced and solar maculopathies. Follow-up showed significant reformation of the EZ as well as improvement of BVA.

16.
Oxid Med Cell Longev ; 2019: 5692958, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31467633

RESUMO

Autophagy is a catabolic pathway activated in response to different cellular stressors, such as damaged organelles, accumulation of misfolded or unfolded proteins, ER stress, accumulation of reactive oxygen species, and DNA damage. Some DNA damage sensors like FOXO3a, ATM, ATR, and p53 are known to be important autophagy regulators, and autophagy seems therefore to have a role in DNA damage response (DDR). Recent studies have partly clarified the pathways that induce autophagy during DDR, but its precise role is still not well known. Previous studies have shown that autophagy alterations induce an increase in DNA damage and in the occurrence of tumor and neurodegenerative diseases, highlighting its fundamental role in the maintenance of genomic stability. During DDR, autophagy could act as a source of energy to maintain cell cycle arrest and to sustain DNA repair activities. In addition, autophagy seems to play a role in the degradation of components involved in the repair machinery. In this paper, molecules which are able to induce oxidative stress and/or DNA damage have been selected and their toxic and genotoxic effects on the U937 cell line have been assessed in the presence of the single compounds and in concurrence with an inhibitor (chloroquine) or an inducer (rapamycin) of autophagy. Our data seem to corroborate the fundamental role of this pathway in response to direct and indirect DNA-damaging agents. The inhibition of autophagy through chloroquine had no effect on the genotoxicity induced by the tested compounds, but it led to a high increase of cytotoxicity. The induction of autophagy, through cotreatment with rapamycin, reduced the genotoxic activity of the compounds. The present study confirms the cytoprotective role of autophagy during DDR; its inhibition can sensitize cancer cells to DNA-damaging agents. The modulation of this pathway could therefore be an innovative approach able to reduce the toxicity of many compounds and to enhance the activity of others, including anticancer drugs.


Assuntos
Autofagia/efeitos dos fármacos , Dano ao DNA/genética , Humanos , Estresse Oxidativo
17.
Klin Monbl Augenheilkd ; 236(4): 516-522, 2019 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-30999329

RESUMO

PURPOSE: The spectrum of intraocular and systemic findings in patients with ocular syphilis is described. Persistent visual dysfunction and structural abnormality, in spite of targeted antibiotic therapy, were identified and analysed. METHODS: Patients with ocular syphilis who were treated at University Hospital Zurich (USZ) between 2010 and 2018 were included in this study. General characteristics, ocular manifestation and visual function (best-corrected visual acuity [BCVA], visual field) before and after treatment were analysed retrospectively. RESULTS: Ocular syphilis was diagnosed in one female and 16 male patients (median age 42 years, range 22 to 53 years). A bilateral infection was present in 11 cases, and 28 of 34 eyes were affected (82%). Manifestations included anterior (n = 3), intermediate (n = 4), posterior (n = 10) uveitis, as well as panuveitis (n = 5) and papillitis (n = 6). Abnormal liquor findings were present in 8 patients (47%). Six patients were human immunodeficiency virus (HIV) positive. In all patients, intravenous benzyl penicillin was initiated and led to inactivation of intraocular inflammation. Before the initial intravenous treatment, all patients received one dose of steroids orally (Prednisone [PDN] 50 to 70 mg). Seven patients had systemic steroids added over the course of the antibiotic treatment being gradually decreased during and after the antibiotic treatment. The initial median BCVA of all affected eyes (n = 28) of 17 patients was 0.1 logMAR (0.8 decimal), range 2.8 to - 0.1 logMAR (light perception to 1.25 decimal). At the last visit, the median BCVA was 0 logMAR, range 0.4 to - 0.1 logMAR (0.4 to 1.25 decimal). Median follow-up time was 11 months (range 3 to 60 months). At the last visit, BCVA of 4 eyes (3 patients) was ≤ 0.6. Six eyes of 5 patients had a persisting scotoma with central visual field defects. Morphologically, disintegration and irregularities of outer retinal layers after central retinitis (5 eyes) and atrophy of the peripapillary retinal nerve fibre layer (4 eyes) after papillitis correlated with abnormal vision. CONCLUSIONS: The spectrum of ocular manifestations in syphilis is broad. Despite targeted antibiotic therapy, more than a third of affected eyes had lasting abnormal vision. Patients with papillitis and retinitis were at an increased risk for persistent visual dysfunction.


Assuntos
Infecções Oculares Bacterianas , Sífilis , Uveíte , Transtornos da Visão , Adulto , Infecções Oculares Bacterianas/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sífilis/complicações , Transtornos da Visão/microbiologia , Acuidade Visual , Adulto Jovem
18.
Klin Monbl Augenheilkd ; 236(4): 511-515, 2019 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-30763957

RESUMO

PURPOSE: Cytomegalovirus (CMV) can cause recurrent or chronic hypertensive anterior uveitis in immunocompetent patients. Antiviral treatment options include topical ganciclovir or systemic valganciclovir. However, recurrences are common after stopping treatment. We evaluated the efficacy of long-term topical ganciclovir therapy as prophylaxis for recurrent activity. METHODS AND PATIENTS: Retrospective analysis of all CMV uveitis patients seen between 2011 and 2018 at Zurich University Hospital. Inclusion criteria were suspected viral anterior uveitis and a positive CMV polymerase chain reaction of the anterior chamber (AC) tap. After diagnosis, topical therapy with ganciclovir gel 5 × daily was started and tapered according to clinical activity. Topical steroids and glaucoma medication were used according to clinical assessment. An active episode was defined as increase in AC inflammatory activity and/or a uveitis-related rise in intraocular pressure (IOP) greater than 25 mmHg. Episodes were analysed before and after initiation of ganciclovir therapy. RESULTS: Six patients, median age 51 (range 24 - 62) years old, were included. All patients had hypertensive unilateral anterior uveitis and presented with small to medium sized endothelial precipitates and with 0.5+ to 2+ AC cells. Median IOP in the affected eye at initial presentation was 43 mmHg (range 36 - 60). Median time from first episode to diagnosis was 19.5 (range 5 - 193) months. Median number of episodes before ganciclovir treatment was 4 (2 - 20), corresponding to a mean of 3.04 episodes per year. Median follow-up time after initiation of ganciclovir medication was 26 (range 4 to 62) months. Median number of episodes under treatment was 1 (range 0 - 6), corresponding to a mean of 0.19 episodes per year (p = 0.04, 2-sided paired t-test). The median (range) for the individually chosen long-term prophylactic dose was ganciclovir gel 2 (0 - 4) times daily, and topical steroids 1 (0 - 2) times daily. Lower doses lead to recurrences in 3 patients (50%). Glaucoma and cataract surgery were performed in 2 patients (33%). CONCLUSION: Although a rare entity in Central Europe, the important feature of CMV uveitis is its hypertensive and recurrent nature. In our cases, topical ganciclovir was found to be an effective treatment. Inflammatory activity was well controlled by using an individually assessed prophylactic dose. Larger studies assessing long-term prophylaxis are desirable.


Assuntos
Antivirais , Infecções por Citomegalovirus , Infecções Oculares Virais , Adulto , Antivirais/uso terapêutico , Humor Aquoso , Citomegalovirus , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/prevenção & controle , Europa (Continente) , Infecções Oculares Virais/tratamento farmacológico , Infecções Oculares Virais/prevenção & controle , Ganciclovir/uso terapêutico , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
19.
Retina ; 39(3): 452-464, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29206759

RESUMO

PURPOSE: To explore morphologic characteristics of choroidal lesions in patients with disseminated Mycobacterium chimaera infection subsequent to open-heart surgery. METHODS: Nine patients (18 eyes) with systemic M. chimaera infection were reviewed. Activity of choroidal lesions were evaluated using biomicroscopy, fundus autofluorescence, enhanced depth imaging optical coherence tomography, fluorescein angiography/indocyanine green angiography, and optical coherence tomography angiography. Relationships of choroidal findings to systemic disease activity were sought. RESULTS: All 9 male patients, aged between 49 and 66 years, were diagnosed with endocarditis and/or aortic graft infection. Mean follow-up was 17.6 months. Four patients had only inactive lesions (mild disease). In all five patients (10 eyes) with progressive ocular disease, indocyanine green angiography was superior to other tests for revealing new lesions and active lesions correlated with hyporeflective choroidal areas on enhanced depth imaging optical coherence tomography. One eye with a large choroidal granuloma developed choroidal neovascularization. Optical coherence tomography angiography showed areas with reduced perfusion at the inner choroid. All 5 patients with progressive ocular disease had evidence of systemic disease activity within ±6 weeks' duration. CONCLUSION: Choroidal manifestation of disseminated M. chimaera infection indicates systemic disease activity. Multimodal imaging is suitable to recognize progressive ocular disease. We propose ophthalmologic screening examinations for patients with M. chimaera infection.


Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Doenças da Coroide/patologia , Infecções por Mycobacterium/patologia , Idoso , Doenças da Coroide/diagnóstico por imagem , Angiofluoresceinografia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Complicações Pós-Operatórias/patologia , Tomografia de Coerência Óptica/métodos
20.
Ophthalmology ; 125(5): e33-e34, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29681303

Assuntos
Quimera , Mycobacterium
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...