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1.
Vet Dermatol ; 35(3): 346-353, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38284278

RESUMO

BACKGROUND: In humans, figurate erythema (FE) represents a heterogenous group of dermatoses with circular or serpiginous erythematous skin lesions; FE has not been reported in cats. OBJECTIVES: To report clinical and histological characteristics and outcomes of FE in sphynx cats from Baltic sea-bordering countries. ANIMALS: Eleven client-owned sphynx cats with FE. MATERIALS AND METHODS: We recruited cases meeting the following criteria: (i) a sphynx breed, (ii) FE with or without scaling, (iii) a chronic, waxing-and-waning course lasting longer than a month and (iv) an absence of other skin diseases. RESULTS: Of 11 cats, there were seven Donskoys, one Peterbald, one Ukrainian Levkoy and two presumed Canadian sphynxes; all except one were males, and the age of onset was <12 months in eight cats. Skin lesions lasted between 1.2 and 56 months, and they consisted of erythematous plaques with a linear-to-serpiginous, annular, gyrate or iris configuration predominating on the trunk and extremities. Scaling was often seen trailing the edge of the centrifugally expanding erythema. All cats were otherwise asymptomatic or mildly pruritic. Dermatophytosis was ruled out by special stains and/or fungal cultures in eight cats. Microscopic lesions revealed focal, mild-to-moderate epidermal hyperplasia and hyperkeratosis, minimal-to-mild dysplasia and subepidermal collagen smudging. Special stains were negative for dermatophytes. The clinical remission of FE was not achieved with diet changes or medical interventions; yet, a spontaneous, transient, partial or complete improvement occurred in most cats. CONCLUSION AND CLINICAL RELEVANCE: This is the first report of FE in sphynx cats from Eastern Europe.


Assuntos
Doenças do Gato , Eritema , Animais , Gatos , Eritema/veterinária , Eritema/patologia , Doenças do Gato/patologia , Masculino , Feminino , Pele/patologia
2.
Vet Dermatol ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38818665

RESUMO

Feline proliferative and necrotising otitis externa (PNOE) is a rare immune-mediated condition, usually self-limiting or responsive to immunosuppressants such as topical tacrolimus. This case report describes two cats with refractory PNOE that responded successfully to oclacitinib. One cat also had middle ear involvement and the other cat had extra-auricular dermatitis.

3.
Vet Dermatol ; 34(5): 425-440, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37316895

RESUMO

BACKGROUND: While the clinical features were described recently, the histopathological characterisation of trunk-dominant canine pemphigus foliaceus (PF) is lacking, and whether it differs from classic facial or insecticide-triggered PF is unknown. HYPOTHESIS/OBJECTIVES: This study describes the histopathological findings of trunk-dominant PF, and compares the results to classic facial and insecticide-triggered PF. ANIMALS: Skin biopsies from 103 dogs with clinically characterised trunk-dominant (n = 33), classic facial (n = 26) and insecticide-triggered PF (n = 44) were included. MATERIALS AND METHODS: Histological sections, randomised and blinded, were scored for over 50 morphological parameters of pustules, epidermis, dermis, adnexa and crusts. Intact pustule area and width were measured by digital microscopy. RESULTS: In trunk-dominant PF, 77 intact pustules were predominantly subcorneal (0.0019-1.940 mm2 area, 0.0470-4.2532 mm wide), and contained from one to over 100 acantholytic keratinocytes. Pustules had boat acantholytic cells, corneocytes, perinuclear eosinophilic rings, neutrophil rosettes, acantholytic cell necrosis, rafts, cling-ons and/or eosinophils. Peripustular epidermal spongiosis, necrosis and lymphocyte exocytosis occurred, as did follicular pustules. Mixed dermal inflammation often contained eosinophils. Trunk-dominant PF did not differ from the other PF groups except for few parameters, such as having fewer rafts (p = 0.003). Additional autoimmune inflammatory patterns occurred in all PF groups. CONCLUSIONS AND CLINICAL RELEVANCE: Trunk-dominant PF and other canine PF variants are histologically similar, which indicates shared pathomechanisms. The identification of common boat acantholytic cells and corneocyte separation has implications for the mechanisms of acantholysis. The diversity of histopathological and polyautoimmunity features support complicated immune mechanisms. Finally, results indicate that diagnostic biopsies cannot differentiate between these PF variants in dogs.


Assuntos
Inseticidas , Pênfigo , Cães , Animais , Pênfigo/veterinária , Pênfigo/diagnóstico , Pele/patologia , Epiderme/patologia , Vesícula/patologia , Vesícula/veterinária , Necrose/veterinária
4.
Int J Mol Sci ; 24(23)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38069284

RESUMO

According to the Cancer Genome Atlas (TCGA), gastric cancers are classified into four molecular subtypes: Epstein-Barr virus-positive (EBV+), tumors with microsatellite instability (MSI), tumors with chromosomal instability (CIN), and genomically stable (GS) tumors. However, the gastric cancer (GC) with chromosomal instability remains insufficiently described and does not have effective markers for molecular and histological verification and diagnosis. The CIN subtype of GC is characterized by chromosomal instability, which is manifested by an increased frequency of aneuploidies and/or structural chromosomal rearrangements in tumor cells. Structural rearrangements in the CIN subtype of GC are not accidental and are commonly detected in chromosomal loci, being abnormal because of specific structural organization. The causes of CIN are still being discussed; however, according to recent data, aberrations in the TP53 gene may cause CIN development or worsen its phenotype. Clinically, patients with the CIN subtype of GC demonstrate poor survival, but receive the maximum benefit from adjuvant chemotherapy. In the review, we consider the molecular mechanisms and possible causes of chromosomal instability in GC, the common rearrangements of chromosomal loci and their impact on the development and clinical course of the disease, as well as the driver genes, their functions, and perspectives on their targeting in the CIN subtype of GC.


Assuntos
Infecções por Vírus Epstein-Barr , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Herpesvirus Humano 4 , Instabilidade Cromossômica , Instabilidade de Microssatélites
5.
Int J Mol Sci ; 24(24)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38139172

RESUMO

Triple-negative breast cancer (TNBC) is the most aggressive molecular subtype, with a poor survival rate compared to others subtypes. For a long time, chemotherapy was the only systemic treatment for TNBC, and the identification of actionable molecular targets might ultimately improve the prognosis for TNBC patients. We performed a genome-wide analysis of DNA methylation at CpG islands on a collection of one hundred ten breast carcinoma samples and six normal breast tissue samples using reduced representation bisulfite sequencing with the XmaI restriction enzyme (XmaI-RRBS) and identified a subset of TNBC samples with significant hypomethylation at the LTB4R/LTB4R2 genes' CpG islands, including CpG dinucleotides covered with cg12853742 and cg21886367 HumanMethylation 450K microarray probes. Abnormal DNA hypomethylation of this region in TNBC compared to normal samples was confirmed by bisulfite Sanger sequencing. Gene expression generally anticorrelates with promoter methylation, and thus, the promoter hypomethylation detected and confirmed in our study might be revealed as an indirect marker of high LTB4R/LTB4R2 expression using a simple methylation-sensitive PCR test. Analysis of RNA-seq expression and DNA methylation data from the TCGA dataset demonstrates that the expression of the LTB4R and LTB4R2 genes significantly negatively correlates with DNA methylation at both CpG sites cg12853742 (R = -0.4, p = 2.6 × 10-6; R = -0.21, p = 0.015) and cg21886367 (R = -0.45, p = 7.3 × 10-8; R = -0.24, p = 0.005), suggesting the upregulation of these genes in tumors with abnormal hypomethylation of their CpG island. Kaplan-Meier analysis using the TCGA-BRCA gene expression and clinical data revealed poorer overall survival for TNBC patients with an upregulated LTB4R. To this day, only the leukotriene inhibitor LY255283 has been tested on an MCF-7/DOX cell line, which is a luminal A breast cancer molecular subtype. Other studies compare the effects of Montelukast and Zafirlukast (inhibitors of the cysteinyl leukotriene receptor, which is different from LTB4R/LTB4R2) on the MDA-MB-231 (TNBC) cell line, with high methylation and low expression levels of LTB4R. In our study, we assess the therapeutic effects of various drugs (including leukotriene receptor inhibitors) with the DepMap gene effect and drug sensitivity data for TNBC cell lines with hypomethylated and upregulated LTB4R/LTB4R2 genes. LY255283, Minocycline, Silibinin, Piceatannol, Mitiglinide, 1-Azakenpaullone, Carbetocin, and Pim-1-inhibitor-2 can be considered as candidates for the additional treatment of TNBC patients with tumors demonstrating LTB4R/LTB4R2 hypomethylation/upregulation. Finally, our results suggest that the epigenetic status of leukotriene B4 receptors is a novel, potential, predictive, and prognostic biomarker for TNBC. These findings might improve individualized therapy for TNBC patients by introducing new therapeutic adjuncts as anticancer agents.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Linhagem Celular Tumoral , Epigenômica , Receptores de Leucotrienos
6.
BMC Pregnancy Childbirth ; 22(1): 633, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35945516

RESUMO

BACKGROUND: A fast adoption of a non-invasive prenatal testing (NIPT) in clinical practice is a global tendency last years. Firstly, in Russia according a new regulation it was possible to perform a widescale testing of pregnant women in chromosomal abnormality risk. The aim of the study-to assess efficiency of using NIPT as a second-line first trimester screening test in Moscow. METHODS: Based on the first trimester combined prenatal screening results 12,700 pregnant women were classified as a high-risk (cut-off ≥ 1:100) and an intermediate-risk (cut-off 1:101 - 1:2500) groups followed by whole genome NIPT. Women from high-risk group and those who had positive NIPT results from intermediate-risk group were considered for invasive prenatal diagnostic. RESULTS: 258 (2.0%) samples with positive NIPT results were detected including 126 cases of trisomy 21 (T21), 40 cases of T18, 12 cases of T13, 41 cases of sex chromosome aneuploidies (SCAs) and 39 cases of rare autosomal aneuploidies (RAAs) and significant copy number variations (CNVs). Statistically significant associations (p < 0.05) were revealed for fetal fraction (FF) and both for some patient's (body mass index and weight) and fetus's (sex and high risk of aneuploidies) characteristics. NIPT showed as a high sensitivity as specificity for common trisomies and SCAs with an overall false positive rate 0.3%. CONCLUSIONS: NIPT demonstrated high sensitivity and specificity. As a second-line screening test it has shown a high efficiency in detecting fetus chromosomal anomalies as well as it could potentially lower the number of invasive procedures in pregnant women.


Assuntos
Transtornos Cromossômicos , Variações do Número de Cópias de DNA , Algoritmos , Aneuploidia , Transtornos Cromossômicos/diagnóstico , Feminino , Humanos , Gravidez , Diagnóstico Pré-Natal/métodos , Trissomia , Síndrome da Trissomía do Cromossomo 18/diagnóstico
7.
Int J Mol Sci ; 23(10)2022 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-35628612

RESUMO

In the last few years, more and more scientists have suggested and confirmed that epigenetic regulators are tightly connected and form a comprehensive network of regulatory pathways and feedback loops. This is particularly interesting for a better understanding of processes that occur in the development and progression of various diseases. Appearing on the preclinical stages of diseases, epigenetic aberrations may be prominent biomarkers. Being dynamic and reversible, epigenetic modifications could become targets for a novel option for therapy. Therefore, in this review, we are focusing on histone modifications and ncRNAs, their mutual regulation, role in cellular processes and potential clinical application.


Assuntos
Epigênese Genética , Código das Histonas , Metilação de DNA , Processamento de Proteína Pós-Traducional , RNA não Traduzido/genética
8.
Vet Dermatol ; 32(4): 311-e84, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34159687

RESUMO

BACKGROUND: Canine demodicosis is a common disease in small animal practice. Although a number of studies evaluating treatment efficacy for canine demodicosis have used clinical scoring systems, none have been validated. OBJECTIVES: This study evaluated the validity, reliability, reproducibility and sensitivity to change of a clinical scoring system for canine demodicosis. METHODS AND MATERIALS: Fifty-eight dogs with generalised demodicosis were evaluated using a clinical scoring system that assessed erythema, comedones/ papules/pustules, follicular casts/scales/crusts and alopecia, rated from none to mild, moderate and severe in 36 body locations. Two evaluators scored lesions at monthly consecutive visits during treatment. Mites were counted to a maximum of 50 in four deep skin scrapings. With >50 mites, the approximate mite number was calculated with the help of a grid drawn onto the slide before placing the scraped material onto it. RESULTS: A Pearson correlation coefficient showed a high interobserver reliability (r = 0.97) between two different clinicians evaluating the same dog. The Wilcoxon signed rank test showed good sensitivity to change with a reduction of clinical scores with each of the first six evaluations (P < 0.0001). A linear mixed model also showed a clear reduction in mite counts (P < 0.001) and clinical scores (P < 0.0001) from the first evaluation with time. CONCLUSION AND CLINICAL RELEVANCE: The clinical scoring system for canine demodicosis evaluated in this study showed a good sensitivity to change and interobserver reliability, and can be used in studies evaluating canine demodicosis.


Assuntos
Doenças do Cão , Infestações por Ácaros , Ácaros , Animais , Doenças do Cão/diagnóstico , Cães , Macrolídeos , Infestações por Ácaros/diagnóstico , Infestações por Ácaros/tratamento farmacológico , Infestações por Ácaros/veterinária , Reprodutibilidade dos Testes
9.
Molecules ; 26(9)2021 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-33922925

RESUMO

Exosomes are the small vesicles that are secreted by different types of normal and tumour cells and can incorporate and transfer their cargo to the recipient cells. The main goal of the present work was to study the tumour exosomes' ability to accumulate the parent mutant DNA or RNA transcripts with their following transfer to the surrounding cells. The experiments were performed on the MCF7 breast cancer cells that are characterized by the unique coding mutation in the PIK3CA gene. Using two independent methods, Sanger sequencing and allele-specific real-time PCR, we revealed the presence of the fragments of the mutant DNA and RNA transcripts in the exosomes secreted by the MCF7 cells. Furthermore, we demonstrated the MCF7 exosomes' ability to incorporate into the heterologous MDA-MB-231 breast cancer cells supporting the possible transferring of the exosomal cargo into the recipient cells. Sanger sequencing of the DNA from MDA-MB-231 cells (originally bearing a wild type of PIK3CA) treated with MCF7 exosomes showed no detectable amount of mutant DNA or RNA; however, using allele-specific real-time PCR, we revealed a minor signal from amplification of a mutant allele, showing a slight increase of mutant DNA in the exosome-treated MDA-MB-231 cells. The results demonstrate the exosome-mediated secretion of the fragments of mutant DNA and mRNA by the cancer cells and the exosomes' ability to transfer their cargo into the heterologous cells.


Assuntos
Neoplasias da Mama/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , DNA de Neoplasias/genética , Exossomos/genética , Alelos , Neoplasias da Mama/patologia , Feminino , Humanos , Células MCF-7 , Mutação/genética , RNA Mensageiro/genética
10.
Can Vet J ; 62(10): 1067-1070, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34602633

RESUMO

An 8-year-old cat was presented with pruritus, purulent paronychia, scaling, crusting, and spontaneous alopecia. Histopathology revealed intraepidermal neutrophilic pustular acantholytic dermatitis and hyperkeratotic cytotoxic interface dermatitis. No thoracic mass was seen on a lateral radiograph. Ectopic thymoma was discovered on necropsy. This case highlights the necessity for thorough investigation of any case of feline exfoliative dermatitis and pemphigus foliaceus for the presence of thymoma. Key clinical message: Comorbidity of exfoliative dermatitis and pemphigus foliaceus in a cat should prompt a thorough investigation for presence of a thymoma, possibly with advanced imaging techniques.


Comorbidité de dermatite exfoliative et de pemphigus foliacé associés à un thymome ectopique chez un chat. Un chat de 8 ans a été présenté avec prurit, panaris purulent, desquamation, croûtes et alopécie spontanée. L'histopathologie a révélé une dermatite acantholytique neutrophilique intra-épidermique et une dermatite d'interface cytotoxique hyperkératosique. Aucune masse thoracique n'a été observée sur une radiographie latérale. Un thymome ectopique a été découvert à l'autopsie. Ce cas met en évidence la nécessité d'une investigation approfondie de tout cas de dermatite exfoliative féline et de pemphigus foliacé pour la présence d'un thymome.Message clinique clé :La comorbidité d'une dermatite exfoliative et de pemphigus foliacé chez un chat devrait inciter à une enquête approfondie pour la présence d'un thymome, éventuellement avec des techniques d'imagerie avancées.(Traduit par Dr Serge Messier).


Assuntos
Doenças do Gato , Dermatite Esfoliativa , Pênfigo , Timoma , Neoplasias do Timo , Animais , Gatos , Comorbidade , Dermatite Esfoliativa/veterinária , Pênfigo/veterinária , Timoma/complicações , Timoma/veterinária , Neoplasias do Timo/veterinária
11.
Int J Mol Sci ; 21(14)2020 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-32664585

RESUMO

Rheumatoid arthritis (RA) is the most common inflammatory arthropathy worldwide. Possible manifestations of RA can be represented by a wide variability of symptoms, clinical forms, and course options. This multifactorial disease is triggered by a genetic predisposition and environmental factors. Both clinical and genealogical studies have demonstrated disease case accumulation in families. Revealing the impact of candidate gene missense variants on the disease course elucidates understanding of RA molecular pathogenesis. A multivariate genomewide association study (GWAS) based analysis identified the genes and signalling pathways involved in the pathogenesis of the disease. However, these identified RA candidate gene variants only explain 30% of familial disease cases. The genetic causes for a significant proportion of familial RA have not been determined until now. Therefore, it is important to identify RA risk groups in different populations, as well as the possible prognostic value of some genetic variants for disease development, progression, and treatment. Our review has two purposes. First, to summarise the data on RA candidate genes and the increased disease risk associated with these alleles in various populations. Second, to describe how the genetic variants can be used in the selection of drugs for the treatment of RA.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/genética , Polimorfismo Genético , Alelos , Antirreumáticos/farmacologia , Artrite Reumatoide/tratamento farmacológico , Citocinas/genética , Progressão da Doença , Resistência a Medicamentos , Feminino , Genes MHC Classe I , Genes MHC da Classe II , Estudos de Associação Genética , Predisposição Genética para Doença , Genética Populacional , Estudo de Associação Genômica Ampla , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Terapia de Alvo Molecular , Polimorfismo de Nucleotídeo Único , Prognóstico , Receptores de Citocinas/genética , Risco , Transdução de Sinais/genética
12.
J Biol Chem ; 293(35): 13750-13765, 2018 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-29945974

RESUMO

The histone lysine methyltransferase nuclear receptor-binding SET domain protein 2 (NSD2, also known as WHSC1/MMSET) is an epigenetic modifier and is thought to play a driving role in oncogenesis. Both NSD2 overexpression and point mutations that increase its catalytic activity are associated with several human cancers. Although NSD2 is an attractive therapeutic target, no potent, selective, and bioactive small molecule inhibitors of NSD2 have been reported to date, possibly due to the challenges of developing high-throughput assays for NSD2. Here, to establish a platform for the discovery and development of selective NSD2 inhibitors, we optimized and implemented multiple assays. We performed quantitative high-throughput screening with full-length WT NSD2 and a nucleosome substrate against a diverse collection of bioactive small molecules comprising 16,251 compounds. We further interrogated 174 inhibitory compounds identified in the primary screen with orthogonal and counter assays and with activity assays based on the clinically relevant NSD2 variants E1099K and T1150A. We selected five confirmed inhibitors for follow-up, which included a radiolabeled validation assay, surface plasmon resonance studies, methyltransferase profiling, and histone methylation in cells. We found that all five NSD2 inhibitors bind the catalytic SET domain and one exhibited apparent activity in cells, validating the workflow and providing a template for identifying selective NSD2 inhibitors. In summary, we have established a robust discovery pipeline for identifying potent NSD2 inhibitors from small-molecule libraries.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores Enzimáticos/farmacologia , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Nucleossomos/metabolismo , Proteínas Repressoras/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Linhagem Celular Tumoral , Inibidores Enzimáticos/química , Ensaios de Triagem em Larga Escala/métodos , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Nucleossomos/efeitos dos fármacos , Proteínas Repressoras/metabolismo , Bibliotecas de Moléculas Pequenas/química
13.
Genes Chromosomes Cancer ; 57(1): 42-47, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28960585

RESUMO

Glioblastoma is the most frequent and aggressive brain tumor in the adult population. Loss of heterozygosity (LOH) at markers of the long arm of chromosome 10 is the most common genetic alteration in glioblastoma, being detectable in up to 80% of cases. We have tested 124 glioblastoma samples for LOH by microsatellite analysis of the 10q23.3-26.3 region which contains the cancer related genes PTEN, FGFR2, MKI67, and MGMT. Then, a real-time quantitative microsatellite analysis (QuMA) was used to qualitatively estimate the change in copy number of this region in the samples with LOH. LOH was detected in 62.1% of the glioblastoma samples. A total of 64 samples with LOH in this region were examined by QuMA. LOH was attributed to a deletion in 37.5% of cases, and uniparental disomy (UPD) in 25% of cases. In 37.5% of cases, deletion and UPD segments alternated within the region: deletions being more frequent than UPD in its proximal part (encompassing PTEN and FGFR2) and both deletions and UPD occurring at the same frequency in its distal part (MGMT). Thus, we have investigated mechanisms of structural alterations of the chromosome region 10q23.3-26.3 in glioblastoma. In addition to a structural deletion of this region, UPD was identified as a frequent cause of LOH. We resume that more detailed studies of glioblastoma at the molecular genetic level are essential in search for potential markers suitable for predicting the disease outcome and the response to treatment.


Assuntos
Neoplasias Encefálicas/genética , Cromossomos Humanos Par 10/genética , Glioblastoma/genética , Dissomia Uniparental , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Glioblastoma/patologia , Heterozigoto , Humanos , Antígeno Ki-67/genética , PTEN Fosfo-Hidrolase/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Proteínas Supressoras de Tumor/genética
14.
Nat Chem Biol ; 11(8): 571-578, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26167872

RESUMO

The CEBPA gene is mutated in 9% of patients with acute myeloid leukemia (AML). Selective expression of a short (30-kDa) CCAAT-enhancer binding protein-α (C/EBPα) translational isoform, termed p30, represents the most common type of CEBPA mutation in AML. The molecular mechanisms underlying p30-mediated transformation remain incompletely understood. We show that C/EBPα p30, but not the normal p42 isoform, preferentially interacts with Wdr5, a key component of SET/MLL (SET-domain/mixed-lineage leukemia) histone-methyltransferase complexes. Accordingly, p30-bound genomic regions were enriched for MLL-dependent H3K4me3 marks. The p30-dependent increase in self-renewal and inhibition of myeloid differentiation required Wdr5, as downregulation of the latter inhibited proliferation and restored differentiation in p30-dependent AML models. OICR-9429 is a new small-molecule antagonist of the Wdr5-MLL interaction. This compound selectively inhibited proliferation and induced differentiation in p30-expressing human AML cells. Our data reveal the mechanism of p30-dependent transformation and establish the essential p30 cofactor Wdr5 as a therapeutic target in CEBPA-mutant AML.


Assuntos
Antineoplásicos/farmacologia , Compostos de Bifenilo/farmacologia , Di-Hidropiridinas/farmacologia , Regulação Neoplásica da Expressão Gênica , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Leucemia Mieloide Aguda/metabolismo , Proteína de Leucina Linfoide-Mieloide/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Sequência de Aminoácidos , Animais , Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Camundongos , Simulação de Acoplamento Molecular , Dados de Sequência Molecular , Terapia de Alvo Molecular , Mutação , Proteína de Leucina Linfoide-Mieloide/genética , Proteína de Leucina Linfoide-Mieloide/metabolismo , Ligação Proteica , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Estrutura Terciária de Proteína , Transdução de Sinais , Células Tumorais Cultivadas
15.
Proc Natl Acad Sci U S A ; 111(35): 12853-8, 2014 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-25136132

RESUMO

SET domain containing (lysine methyltransferase) 7 (SETD7) is implicated in multiple signaling and disease related pathways with a broad diversity of reported substrates. Here, we report the discovery of (R)-PFI-2-a first-in-class, potent (Ki (app) = 0.33 nM), selective, and cell-active inhibitor of the methyltransferase activity of human SETD7-and its 500-fold less active enantiomer, (S)-PFI-2. (R)-PFI-2 exhibits an unusual cofactor-dependent and substrate-competitive inhibitory mechanism by occupying the substrate peptide binding groove of SETD7, including the catalytic lysine-binding channel, and by making direct contact with the donor methyl group of the cofactor, S-adenosylmethionine. Chemoproteomics experiments using a biotinylated derivative of (R)-PFI-2 demonstrated dose-dependent competition for binding to endogenous SETD7 in MCF7 cells pretreated with (R)-PFI-2. In murine embryonic fibroblasts, (R)-PFI-2 treatment phenocopied the effects of Setd7 deficiency on Hippo pathway signaling, via modulation of the transcriptional coactivator Yes-associated protein (YAP) and regulation of YAP target genes. In confluent MCF7 cells, (R)-PFI-2 rapidly altered YAP localization, suggesting continuous and dynamic regulation of YAP by the methyltransferase activity of SETD7. These data establish (R)-PFI-2 and related compounds as a valuable tool-kit for the study of the diverse roles of SETD7 in cells and further validate protein methyltransferases as a druggable target class.


Assuntos
Inibidores Enzimáticos/farmacologia , Epigênese Genética/efeitos dos fármacos , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Histona-Lisina N-Metiltransferase/metabolismo , Pirrolidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/farmacologia , Tetra-Hidroisoquinolinas/farmacologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Fibroblastos/efeitos dos fármacos , Via de Sinalização Hippo , Histona-Lisina N-Metiltransferase/genética , Humanos , Células MCF-7 , Metiltransferases/antagonistas & inibidores , Metiltransferases/metabolismo , Mutação , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Proteínas Serina-Treonina Quinases/genética , Estrutura Terciária de Proteína , Pirrolidinas/química , Relação Estrutura-Atividade , Sulfonamidas/química , Tetra-Hidroisoquinolinas/química , Fatores de Transcrição , Proteínas de Sinalização YAP
16.
J Biol Chem ; 290(30): 18678-98, 2015 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-26071590

RESUMO

The haloacid dehalogenase (HAD)-like enzymes comprise a large superfamily of phosphohydrolases present in all organisms. The Saccharomyces cerevisiae genome encodes at least 19 soluble HADs, including 10 uncharacterized proteins. Here, we biochemically characterized 13 yeast phosphatases from the HAD superfamily, which includes both specific and promiscuous enzymes active against various phosphorylated metabolites and peptides with several HADs implicated in detoxification of phosphorylated compounds and pseudouridine. The crystal structures of four yeast HADs provided insight into their active sites, whereas the structure of the YKR070W dimer in complex with substrate revealed a composite substrate-binding site. Although the S. cerevisiae and Escherichia coli HADs share low sequence similarities, the comparison of their substrate profiles revealed seven phosphatases with common preferred substrates. The cluster of secondary substrates supporting significant activity of both S. cerevisiae and E. coli HADs includes 28 common metabolites that appear to represent the pool of potential activities for the evolution of novel HAD phosphatases. Evolution of novel substrate specificities of HAD phosphatases shows no strict correlation with sequence divergence. Thus, evolution of the HAD superfamily combines the conservation of the overall substrate pool and the substrate profiles of some enzymes with remarkable biochemical and structural flexibility of other superfamily members.


Assuntos
Evolução Molecular , Hidrolases/química , Hidrolases/metabolismo , Saccharomyces cerevisiae/enzimologia , Sequência de Aminoácidos/genética , Sítios de Ligação , Catálise , Domínio Catalítico/genética , Cristalografia por Raios X , Genoma Fúngico , Hidrolases/genética , Cinética , Filogenia , Estrutura Terciária de Proteína , Alinhamento de Sequência , Especificidade por Substrato
17.
Biochim Biophys Acta ; 1850(9): 1842-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26002201

RESUMO

BACKGROUND: Dysregulation of methylation of lysine 36 on histone H3 (H3K36) have been implicated in a variety of diseases including cancers. ASH1L and SETD2 are two enzymes among others that catalyze H3K36 methylation. H3K4 methylation has also been reported for ASH1L. METHODS: Radioactivity-based enzyme assays, Western and immunoblotting using specific antibodies and molecular modeling were used to characterize substrate specificity of ASH1L and SETD2. RESULTS: Here we report on the assay development and kinetic characterization of ASH1L and SETD2 and their substrate specificities in vitro. Both enzymes were active with recombinant nucleosome as substrate. However, SETD2 but not ASH1L methylated histone peptides as well indicating that the interaction of the basic post-SET extension with substrate may not be critical for SETD2 activity. Both enzymes were not active with nucleosome containing a H3K36A mutation indicating their specificity for H3K36. Analyzing the methylation state of the products of ASH1L and SETD2 reactions also confirmed that both enzymes mono- and dimethylate H3K36 and are inactive with H3K4 as substrate, and that only SETD2 is able to trimethylate H3K36 in vitro. CONCLUSIONS: We determined the kinetic parameters for ASH1L and SETD2 activity enabling screening for inhibitors that can be used to further investigate the roles of these two proteins in health and disease. Both ASH1L and SETD2 are H3K36 specific methyltransferases but only SETD2 can trimethylate this mark. The basic post-SET extension is critical for ASH1L but not SETD2 activity. GENERAL SIGNIFICANCE: We provide full kinetic characterization of ASH1L and SETD2 activity.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Proteínas de Ligação a DNA/química , Histona-Lisina N-Metiltransferase/química , Humanos , Cinética , Metilação , Modelos Moleculares , Dados de Sequência Molecular , Especificidade por Substrato , Fatores de Transcrição/química
18.
Tumour Biol ; 37(7): 9899-907, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26813565

RESUMO

The renal cell carcinoma is the ninth most common cancer with an increasing occurrence and mortality. Recoverin is the first retina-specific photoreceptor protein that was shown to undergo aberrant expression, due to its promoter demethylation, as a cancer-retina antigen in a number of malignant tumors. In this work, we demonstrated that recoverin is indeed expressed in 68.4 % of patients with different subtypes of renal cell carcinoma, and this expression has tendency to correlate with tumor size. Interestingly, 91.7 % of patients with the benign renal tumor, oncocytoma, express recoverin as well in their tumor. Epigenetic analysis of the recoverin gene promoter revealed a stable mosaic methylation pattern with the predominance of the methylated state, with the exception of -80 and 56 CpG dinucleotides (CpGs). While the recoverin expression does not correlate withoverall survival of the tumor patients, the methylation of the recoverin gene promoter at -80 position is associated with better overall survival of the patients. This work is the first report pointing towards the association of overall survival of renal cell carcinoma (RCC) patients with promoter methylation of a cancer-retina antigen. Taken together, these data allow to consider recoverin as a potential therapeutic target and/or marker for renal tumors.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Papilar/patologia , Carcinoma de Células Renais/patologia , Metilação de DNA , Neoplasias Renais/patologia , Recoverina/metabolismo , Idoso , Biomarcadores Tumorais/genética , Western Blotting , Carcinoma Papilar/genética , Carcinoma Papilar/metabolismo , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real , Recoverina/genética , Taxa de Sobrevida
19.
Rheumatol Int ; 35(5): 891-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25344846

RESUMO

The aim of our study was to study the changes in the clinical picture and outcomes of granulomatosis with polyangiitis (Wegener's) (GPA) over 40 years. Two hundred and forty-two consecutive patients with GPA were distributed into retrospective (1970-2003) and prospective (2004-2012) cohorts. Anti-neutrophil cytoplasmic antibodies were present in 82.6 % of patients. In 78.0 % of patients, diagnosis was confirmed histologically. We compared the clinical features of GPA and the incidence of the major and minor relapses and mortality in the two cohorts. The majority of patients in both cohorts had generalized GPA that involved upper respiratory tract (retrospective 89.5 % vs prospective 82.85 %), kidneys (60.5 vs 50.8 %) and lungs (64.0 vs 52.3 %). The total duration of follow-up in the retrospective and prospective cohorts was 468 and 397 patients-years, respectively. In the prospective cohort, we found trend to lower incidence of relapses (54.2 vs 66.2 per 100 patient-year; p = ns; odds ratio 0.82; 95 % CI 0.53-1.21) and significantly lower mortality (4.3 vs 7.9 per 100 patient-year; p = 0.04; odds ratio 0.54; 95 % CI 0.31-0.94). The leading causes of death in the retrospective cohort were lung disease (37.8 %), complications of immunosuppressive treatment (35.1 %) and kidney failure (13.5 %). In the prospective cohort, patients rarely died from terminal uraemia and pulmonary complications (0.0 and 17.6 %) while the proportion of cardiovascular events and complications of the immunosuppression as the causes of death increased (29.4 and 47.1 %). Modern treatment apparently reduced the incidence of relapses and mortality and modified the causes of death in the GPA patients.


Assuntos
Granulomatose com Poliangiite/mortalidade , Falência Renal Crônica/mortalidade , Pneumopatias/mortalidade , Adulto , Anticorpos Anticitoplasma de Neutrófilos/imunologia , Estudos de Coortes , Feminino , Granulomatose com Poliangiite/tratamento farmacológico , Granulomatose com Poliangiite/fisiopatologia , Humanos , Imunossupressores/efeitos adversos , Nefropatias/mortalidade , Nefropatias/fisiopatologia , Falência Renal Crônica/fisiopatologia , Pneumopatias/fisiopatologia , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Estudos Prospectivos , Recidiva , Doenças Respiratórias/mortalidade , Doenças Respiratórias/fisiopatologia , Estudos Retrospectivos , Federação Russa , Índice de Gravidade de Doença , Adulto Jovem
20.
Mol Syst Biol ; 9: 665, 2013 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-23670538

RESUMO

Nucleotide degradation is a universal metabolic capability. Here we combine metabolomics, genetics and biochemistry to characterize the yeast pathway. Nutrient starvation, via PKA, AMPK/SNF1, and TOR, triggers autophagic breakdown of ribosomes into nucleotides. A protein not previously associated with nucleotide degradation, Phm8, converts nucleotide monophosphates into nucleosides. Downstream steps, which involve the purine nucleoside phosphorylase, Pnp1, and pyrimidine nucleoside hydrolase, Urh1, funnel ribose into the nonoxidative pentose phosphate pathway. During carbon starvation, the ribose-derived carbon accumulates as sedoheptulose-7-phosphate, whose consumption by transaldolase is impaired due to depletion of transaldolase's other substrate, glyceraldehyde-3-phosphate. Oxidative stress increases glyceraldehyde-3-phosphate, resulting in rapid consumption of sedoheptulose-7-phosphate to make NADPH for antioxidant defense. Ablation of Phm8 or double deletion of Pnp1 and Urh1 prevent effective nucleotide salvage, resulting in metabolite depletion and impaired survival of starving yeast. Thus, ribose salvage provides means of surviving nutrient starvation and oxidative stress.


Assuntos
Regulação Fúngica da Expressão Gênica , N-Glicosil Hidrolases/genética , Nucleotídeos/metabolismo , Purina-Núcleosídeo Fosforilase/genética , Ribose/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Gliceraldeído 3-Fosfato/metabolismo , N-Glicosil Hidrolases/deficiência , NADP/metabolismo , Via de Pentose Fosfato/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Purina-Núcleosídeo Fosforilase/deficiência , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Transdução de Sinais , Estresse Fisiológico/genética , Fosfatos Açúcares , Transaldolase/genética , Transaldolase/metabolismo
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