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The rapid synthesis of a range of enantioenriched allylic esters is enabled by a new 3-component catalytic enantioselective 1,2-carboesterification of readily available dienes with carboxylic acids and potassium alkyltrifluoroborates. The chiral copper catalyst, formed in situ from Cu(OTf)2 and (4S,4'S)-2,2'-(cyclopentane-1,1-diyl)bis(4-phenyl-4,5-dihydrooxazole), is implicated in both the generation of alkyl radicals from the alkyltrifluoroborates as well as the enantioselective formation of C-O bonds. Potassium salts of primary and secondary alkyltrifluoroborates as well as several benzylic trifluoroborates, tert-butyltrifluoroborate, and phenyltrifluoroborate participate in the reaction. The regioselectivity and enantioselectivity are strongly impacted by variations in all of the reaction components, which in turn are thought to impact the C-O bond-forming reductive elimination from a [Cu(III)] intermediate.
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Ankylosing spondylitis (AS) is an inflammatory disease leading to spine ankylosis; however, the mechanisms behind new bone formation are still not fully understood. Single Nucleotide Polymorphisms (SNPs) in PTGER4, encoding for the receptor EP4 of prostaglandin E2 (PGE2), are associated with AS. Since the PGE2-EP4 axis participates in inflammation and bone metabolism, this work aims at investigating the influence of the prostaglandin-E2 axis on radiographic progression in AS. In 185 AS (97 progressors), baseline serum PGE2 predicted progression, and PTGER4 SNP rs6896969 was more frequent in progressors. Increased EP4/PTGER4 expression was observed in AS circulating immune cells, synovial tissue, and bone marrow. CD14highEP4 + cells frequency correlated with disease activity, and when monocytes were cocultured with mesenchymal stem cells, the PGE2/EP4 axis induced bone formation. In conclusion, the Prostaglandin E2 axis is involved in bone remodelling and may contribute to the radiographic progression in AS due to genetic and environmental upregulation.
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Dinoprostona , Espondilitis Anquilosante , Humanos , Subtipo EP4 de Receptores de Prostaglandina E/genética , Subtipo EP4 de Receptores de Prostaglandina E/metabolismo , Espondilitis Anquilosante/diagnóstico por imagen , Espondilitis Anquilosante/genéticaRESUMEN
BACKGROUND: Although the majority of human papillomavirus (HPV) infections are cleared by the immune system, a small percentage of them progress to develop HPV-driven cancers. Cervical cancer studies highlight that HPV persistence and cancer risk are associated with genetic factors, especially at the human leukocyte antigen (HLA) genes. This study was conducted to investigate such associations in head and neck cancer (HNC). METHODS: In all, 192 patients with HNC and 384 controls were genotyped with the Infinium Global Screening Array (Illumina, Inc). HLA variants were imputed with SNP2HLA, and an association analysis was performed by logistic regression. RESULTS: HPV-positive HNCs were significantly associated with single-nucleotide polymorphisms (SNPs) at DRB1_32660090 (P = 1.728 × 10-6 ) and DRB1_32660116 (P = 1.728 × 10-6 ) and with the amino acid variant DRB1_11_32660115 (P = 1.728 × 10-6 ). None of these associations were observed in the HPV-negative cohort, and this suggested their specificity to convey risk for HPV-associated HNCs. In general, associations observed for HPV-negative HNC were relatively weak, and variants in the HLA-DPA1 region were the strongest among them (P = 4.531 × 10-4 ). Several lead signals reported by previous HNC genome-wide association studies, including SNPs rs3135001 (P = .012), rs1049055 (P = .012), and rs34518860 (P = .029) and allele HLA-DQB1*06 (P = .009), were replicated in the current study. However, these associations were limited to the HPV-positive HNC group. Several cervical cancer-associated HLA variants, including SNPs rs9272143 (P = .002) and rs9271858 (P = .002) and alleles HLA-B-1501 (P = .009) and HLA-B-15 (P = .015), were also exclusively associated with HPV-positive HNC. CONCLUSIONS: HPV-positive HNC risk is associated with distinct HLA variants, and some of them are shared by both cervical cancer and HPV-positive HNC. Human papillomavirus (HPV)-positive head and neck cancer (HNC) risk is associated with distinct human leukocyte antigen variants, and some of them are shared by both cervical cancer and HPV-positive HNC. LAY SUMMARY: Cervical cancer studies highlight that human papillomavirus (HPV)-driven cancer risk is linked with human leukocyte antigen (HLA) polymorphism. Hence, the current study was designed to investigate the HLA associations in HPV-positive and HPV-negative head and neck cancer (HNC) and compare these associations with cervical cancer. Several lead signals reported by previous HNC and cervical genome-wide association studies were replicated in the current study. However, these associations were limited to the HPV-positive HNC group, and this suggests that HPV-positive HNC risk is associated with distinct HLA variants, and some of them are shared by both cervical cancer and HPV-positive HNC.
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Alphapapillomavirus , Neoplasias de Cabeza y Cuello , Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Alphapapillomavirus/genética , Femenino , Estudio de Asociación del Genoma Completo , Neoplasias de Cabeza y Cuello/complicaciones , Neoplasias de Cabeza y Cuello/genética , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase II/genética , Humanos , Papillomaviridae/genética , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/genética , Polimorfismo de Nucleótido SimpleRESUMEN
The enantioselective copper-catalyzed oxidative coupling of alkenols with styrenes for the construction of dihydropyrans, isochromans, pyrans and morpholines is reported. A concise formal synthesis of a σ1 receptor ligand using this alkene carboetherification methodology was demonstrated. Ligand, solvent and base all impact reaction efficiency. DFT transition state calculations are presented.
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Solid organ transplant recipients (SOTRs) have elevated risks for basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), especially in high UVR environments. We assessed whether polygenic risk scores can improve the prediction of BCC and SCC risks and multiplicity over and above the traditional risk factors in SOTRs in a high UV setting. We built polygenic risk scores for BCC (n = 594,881) and SCC (n = 581,431) using UK Biobank and 23andMe datasets, validated them in the Australian QSkin Sun and Health Study cohort (n > 6,300), and applied them in SOTRs in the skin tumor in allograft recipients cohort from Queensland, Australia, a high UV environment. About half of the SOTRs with a high genetic risk developed BCC (absolute risk = 45.45%, 95% confidence interval = 33.14-58.19%) and SCC (absolute risk = 44.12%, 95% confidence interval = 32.08-56.68%). For both cancers, SOTRs in the top quintile were at >3-fold increased risk relative to those in the bottom quintile. The respective polygenic risk scores improved risk predictions by 2% for BCC (area under the curve = 0.77 vs. 0.75, P = 0.0691) and SCC (area under the curve = 0.84 vs. 0.82, P = 0.0260), over and above the established risk factors, and 19.03% (for BCC) and 18.10% (for SCC) of the SOTRs were reclassified in a high/medium/low risk scenario. The polygenic risk scores also added predictive accuracy for tumor multiplicity (BCC R2 = 0.21 vs. 0.19, P = 3.2 × 10-3; SCC R2 = 0.30 vs. 0.27, P = 4.6 × 10-4).
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Carcinoma Basocelular/etiología , Carcinoma de Células Escamosas/etiología , Terapia de Inmunosupresión/efectos adversos , Trasplante de Órganos/efectos adversos , Neoplasias Cutáneas/etiología , Rayos Ultravioleta/efectos adversos , Adulto , Humanos , Persona de Mediana Edad , Factores de RiesgoRESUMEN
OBJECTIVE: We undertook this study to evaluate the activation and functional relevance of inflammasome pathways in ankylosing spondylitis (AS) patients and rodent models and their relationship to dysbiosis. METHODS: An inflammasome pathway was evaluated in the gut and peripheral blood from 40 AS patients using quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR), immunohistochemistry (IHC), flow cytometry, and confocal microscopy, and was compared to that of 20 healthy controls and 10 patients with Crohn's disease. Bacteria was visualized using silver stain in human samples, and antibiotics were administered to HLA-B27-transgenic rats. The NLRP3 inhibitor MCC950 was administered to SKG mice, and ileal and joint tissues were assessed by IHC analysis and real-time qRT-PCR. The role of inflammasome in modulating the interleukin-23 (IL-23)/IL-17 axis was studied ex vivo. RESULTS: Expression levels of Nlrp3, Nlrc4, and Aim2 were increased in the gut of HLA-B27-transgenic rats and reduced by antibiotic treatment (P < 0.05). In curdlan-treated SKG mice, NLRP3 blockade prevented ileitis and delayed arthritis onset (P < 0.05). Compared to healthy controls, AS patients demonstrated overexpression of NLRP3 (fold induction 2.33 versus 22.2; P < 0.001), NLRC4 (fold induction 1.90 versus 6.47; P < 0.001), AIM2 (fold induction 2.40 versus 20.8; P < 0.001), CASP1 (fold induction 2.53 versus 24.8; P < 0.001), IL1B (fold induction 1.07 versus 10.93; P < 0.001), and IL18 (fold induction 2.56 versus 15.67; P < 0.001) in the ileum, and caspase 1 activity was increased (P < 0.01). The score of adherent and invasive mucosa-associated bacteria was higher in AS (P < 0.01) and correlated with the expression of inflammasome components in peripheral blood mononuclear cells (P < 0.001). NLRP3 expression was associated with disease activity (the Ankylosing Spondylitis Disease Activity Score using the C-reactive protein level) (r2 = 0.28, P < 0.01) and with IL23A expression (r2 = 0.34, P < 0.001). In vitro, inflammasome activation in AS monocytes was paralleled by increased serum levels of IL-1ß and IL-18. Induction of IL23A, IL17A, and IL22 was IL-1ß-dependent. CONCLUSION: Inflammasome activation occurs in rodent models of AS and in AS patients, is associated with dysbiosis, and is involved in triggering ileitis in SKG mice. Inflammasomes drive type III cytokine production with an IL-1ß-dependent mechanism in AS patients.
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Enfermedad de Crohn/inmunología , Disbiosis/inmunología , Microbioma Gastrointestinal/inmunología , Íleon/inmunología , Inflamasomas/inmunología , Articulaciones/inmunología , Proteína con Dominio Pirina 3 de la Familia NLR/inmunología , Espondilitis Anquilosante/inmunología , Adolescente , Adulto , Animales , Antibacterianos/farmacología , Proteínas Adaptadoras de Señalización CARD/inmunología , Proteínas Adaptadoras de Señalización CARD/metabolismo , Proteínas de Unión al Calcio/inmunología , Proteínas de Unión al Calcio/metabolismo , Estudios de Casos y Controles , Caspasa 1/inmunología , Caspasa 1/metabolismo , Enfermedad de Crohn/microbiología , Proteínas de Unión al ADN/inmunología , Proteínas de Unión al ADN/metabolismo , Femenino , Furanos/farmacología , Antígeno HLA-B27/genética , Humanos , Ileítis/inmunología , Ileítis/metabolismo , Ileítis/patología , Íleon/efectos de los fármacos , Íleon/metabolismo , Íleon/patología , Inmunohistoquímica , Indenos/farmacología , Interleucina-17/inmunología , Interleucina-18/inmunología , Interleucina-18/metabolismo , Interleucina-1beta/inmunología , Interleucina-1beta/metabolismo , Interleucina-23/inmunología , Articulaciones/efectos de los fármacos , Articulaciones/metabolismo , Articulaciones/patología , Masculino , Ratones , Persona de Mediana Edad , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Ratas , Ratas Transgénicas , Receptores de Superficie Celular/inmunología , Receptores de Superficie Celular/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Espondilitis Anquilosante/microbiología , Sulfonamidas/farmacología , Adulto JovenRESUMEN
A direct assembly of secondary benzylureas and related amine derivatives via copper-catalyzed carboamination of styrenes with potassium alkyltrifluoroborates and ureas, anilines, or an amide is reported. Terminal and 1,2-disubstituted alkenes, as well as dienes, participate in this three-component coupling reaction. The reaction mechanism likely involves the addition of an alkyl radical to the styrene, followed by metal-mediated oxidative coupling of the resulting benzylic radical with the amine derivative. Factors that impact substrate reactivity and regioselectivity are discussed.
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Aminas/química , Cobre/química , Estireno/química , Ureasa/química , Ureasa/síntesis química , Alquenos/química , Catálisis , Técnicas de Química SintéticaRESUMEN
Chromosome arm aneuploidies (CAAs) are pervasive in cancers. However, how they affect cancer development, prognosis and treatment remains largely unknown. Here, we analyse CAA profiles of 23,427 tumours, identifying aspects of tumour evolution including probable orders in which CAAs occur and CAAs predicting tissue-specific metastasis. Both haematological and solid cancers initially gain chromosome arms, while only solid cancers subsequently preferentially lose multiple arms. 72 CAAs and 88 synergistically co-occurring CAA pairs multivariately predict good or poor survival for 58% of 6977 patients, with negligible impact of whole-genome doubling. Additionally, machine learning identifies 31 CAAs that robustly alter response to 56 chemotherapeutic drugs across cell lines representing 17 cancer types. We also uncover 1024 potential synthetic lethal pharmacogenomic interactions. Notably, in predicting drug response, CAAs substantially outperform mutations and focal deletions/amplifications combined. Thus, CAAs predict cancer prognosis, shape tumour evolution, metastasis and drug response, and may advance precision oncology.
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Aneuploidia , Cromosomas Humanos , Resistencia a Antineoplásicos/genética , Tasa de Mutación , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Línea Celular Tumoral , Humanos , Estimación de Kaplan-Meier , Aprendizaje Automático , Modelos Biológicos , Neoplasias/mortalidad , Neoplasias/patología , Pronóstico , Procesos EstocásticosRESUMEN
Advances in genomic technology have enabled a greater understanding of the genetics of common immune-mediated diseases such as ankylosing spondylitis (AS), inflammatory bowel disease (IBD) and psoriasis. The substantial overlap in genetically identified pathogenic pathways has been demonstrated between these diseases. However, to date, gene discovery approaches have only mapped a minority of the heritability of these common diseases, and most disease-associated variants have been found to be non-coding, suggesting mechanisms of disease-association through transcriptional regulatory effects.Epigenetics is a major interface between genetic and environmental modifiers of disease and strongly influence transcription. DNA methylation is a well-characterised epigenetic mechanism, and a highly stable epigenetic marker, that is implicated in disease pathogenesis. DNA methylation is an under-investigated area in immune-mediated diseases, and many studies in the field are affected by experimental design limitations, related to study design, technical limitations of the methylation typing methods employed, and statistical issues. This has resulted in both sparsity of investigations into disease-related changes in DNA methylation, a paucity of robust findings, and difficulties comparing studies in the same disease.In this review, we cover the basics of DNA methylation establishment and control, and the methods used to examine it. We examine the current state of DNA methylation studies in AS, IBD and psoriasis; the limitations of previous studies; and the best practices for DNA methylation studies. The purpose of this review is to assist with proper experimental design and consistency of approach in future studies to enable a better understanding of the functional role of DNA methylation in immune-mediated disease.
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Metilación de ADN , Epigenómica/métodos , Enfermedades Inflamatorias del Intestino/genética , Psoriasis/genética , Espondilitis Anquilosante/genética , Predisposición Genética a la Enfermedad/genética , HumanosRESUMEN
Pleural mesothelioma is a cancer of serosal surfaces caused by environmental exposure to asbestos. Clinical outcome remains poor and while trials of new treatments are ongoing it remains an understudied cancer. Mesothelioma cell lines can readily be grown from primary tumour and from tumour cells shed into pleural effusion with the latter representing a particularly valuable source of DNA in clinical settings, procurable without the need for additional invasive procedures. However, it is not well understood how accurately patient-derived cultured tumour cells represent the molecular characteristics of their primary tumour. We used whole-genome sequencing of primary tumour and matched cultured cells to comprehensively characterize mutations and structural alterations. Most cases had complex rearranged genomes with evidence of chromoanagenesis and rearrangements reminiscent of chromoplexy. Many of the identified driver mutations were structural, indicating that mesothelioma is often caused by structural alterations and catastrophic genomic events, rather than point mutations. Because the majority of genomic changes detected in tumours were also displayed by the genomes of cultured tumour cells, we conclude that low-passage cultured tumour cells are generally suitable for molecular characterization of mesothelioma and may be particularly useful where tissue samples with high tumour cell content are not available. However, the subclonal compositions of the cell lines did not fully recapitulate the subclonal diversity of the primary tumours. Furthermore, longitudinal acquisition of major alterations in subclonal cell populations was observed after long-term passaging. These two factors define limitations of tumour-derived cell lines as genomic substrate for clinical purposes.
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Mesotelioma/genética , Neoplasias Pleurales/genética , Secuenciación Completa del Genoma , Línea Celular Tumoral , Humanos , Mesotelioma/patología , Mutación , Neoplasias Pleurales/patologíaRESUMEN
BACKGROUND: Maturity-onset diabetes of the young (MODY) is caused by autosomal dominant mutations in one of 13 confirmed genes. Estimates of MODY prevalence vary widely, as genetic screening is usually restricted based on clinical features, even in population studies. We aimed to determine prevalence of MODY variants in a large and unselected pediatric diabetes cohort. METHODS: MODY variants were assessed using massively parallel sequencing in the population-based diabetes cohort (n = 1363) of the sole tertiary pediatric diabetes service for Western Australia (population 2.6 million). All individuals were screened, irrespective of clinical features. MODY variants were also assessed in a control cohort (n = 993). RESULTS: DNA and signed consent were available for 821 children. Seventeen children had pathogenic/likely pathogenic variants in MODY genes, two diagnosed with type 2 diabetes, four diagnosed with antibody-negative type 1 diabetes (T1DM), three diagnosed with antibody-positive T1DM, and eight previously diagnosed with MODY. Prevalence of MODY variants in the sequenced cohort was 2.1%, compared to 0.3% of controls. CONCLUSIONS: This is the first comprehensive study of MODY variants in an unselected population-based pediatric diabetes cohort. The observed prevalence, increasing access to rapid and affordable genetic screening, and significant clinical implications suggest that genetic screening for MODY could be considered for all children with diabetes, irrespective of other clinical features.
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Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/genética , Pruebas Genéticas/métodos , Edad de Inicio , Estudios de Casos y Controles , Niño , Estudios de Cohortes , Análisis Mutacional de ADN/métodos , Diabetes Mellitus Tipo 2/diagnóstico , Femenino , Frecuencia de los Genes , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Mutación INDEL , Masculino , Mutación , Polimorfismo de Nucleótido Simple , Prevalencia , Australia Occidental/epidemiologíaRESUMEN
Chikungunya virus (CHIKV) is an arthritogenic alphavirus causing epidemics of acute and chronic arthritic disease. Herein we describe a comprehensive RNA-Seq analysis of feet and lymph nodes at peak viraemia (day 2 post infection), acute arthritis (day 7) and chronic disease (day 30) in the CHIKV adult wild-type mouse model. Genes previously shown to be up-regulated in CHIKV patients were also up-regulated in the mouse model. CHIKV sequence information was also obtained with up to ≈8% of the reads mapping to the viral genome; however, no adaptive viral genome changes were apparent. Although day 2, 7 and 30 represent distinct stages of infection and disease, there was a pronounced overlap in up-regulated host genes and pathways. Type I interferon response genes (IRGs) represented up to ≈50% of up-regulated genes, even after loss of type I interferon induction on days 7 and 30. Bioinformatic analyses suggested a number of interferon response factors were primarily responsible for maintaining type I IRG induction. A group of genes prominent in the RNA-Seq analysis and hitherto unexplored in viral arthropathies were granzymes A, B and K. Granzyme A-/- and to a lesser extent granzyme K-/-, but not granzyme B-/-, mice showed a pronounced reduction in foot swelling and arthritis, with analysis of granzyme A-/- mice showing no reductions in viral loads but reduced NK and T cell infiltrates post CHIKV infection. Treatment with Serpinb6b, a granzyme A inhibitor, also reduced arthritic inflammation in wild-type mice. In non-human primates circulating granzyme A levels were elevated after CHIKV infection, with the increase correlating with viral load. Elevated granzyme A levels were also seen in a small cohort of human CHIKV patients. Taken together these results suggest granzyme A is an important driver of arthritic inflammation and a potential target for therapy. TRIAL REGISTRATION: ClinicalTrials.gov NCT00281294.
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Artritis/virología , Fiebre Chikungunya/genética , Fiebre Chikungunya/inmunología , Granzimas/inmunología , Inflamación/virología , Animales , Virus Chikungunya , Modelos Animales de Enfermedad , Granzimas/análisis , Granzimas/biosíntesis , Humanos , Inmunohistoquímica , Macaca fascicularis , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , ARN Mensajero/análisis , TranscriptomaRESUMEN
Calypso is an easy-to-use online software suite that allows non-expert users to mine, interpret and compare taxonomic information from metagenomic or 16S rDNA datasets. Calypso has a focus on multivariate statistical approaches that can identify complex environment-microbiome associations. The software enables quantitative visualizations, statistical testing, multivariate analysis, supervised learning, factor analysis, multivariable regression, network analysis and diversity estimates. Comprehensive help pages, tutorials and videos are provided via a wiki page. Availability and Implementation: The web-interface is accessible via http://cgenome.net/calypso/ . The software is programmed in Java, PERL and R and the source code is available from Zenodo ( https://zenodo.org/record/50931 ). The software is freely available for non-commercial users. Contact: l.krause@uq.edu.au. Supplementary information: Supplementary data are available at Bioinformatics online.
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Minería de Datos/métodos , Ambiente , Metagenoma , Microbiota/fisiología , Programas Informáticos , Humanos , Internet , Microbiota/genética , Plantas , ARN Ribosómico 16S , Estadística como Asunto , Aprendizaje Automático Supervisado , SimbiosisRESUMEN
Hair follicles are skin appendages that undergo periods of growth (anagen), regression (catagen), and rest (telogen) regulated by their mesenchymal component, the dermal papilla (DP). On the basis of the reports of its specific expression in the DP, we investigated signal transducer and activator of transcription (STAT5) activation during hair development and cycling. STAT5 activation in the DP began in late catagen, reaching a peak in early anagen before disappearing for the rest of the cycle. This was confirmed by the expression profile of suppressor of cytokine signaling 2, a STAT5 target in the DP. This pattern of expression starts after the first postnatal hair cycle. Quantification of hair cycling using the Flash canonical Wnt signaling in vivo bioluminescence reporter found that conditional knockout of STAT5A/B in the DP targeted through Cre-recombinase under the control of the Sox18 promoter resulted in delayed anagen entry compared with control. Microarray analysis of STAT5 deletion versus control revealed key changes in tumor necrosis factor-α, Wnt, and fibroblast growth factor ligands, known for their role in inducing anagen entry. We conclude that STAT5 activation acts as a mesenchymal switch to trigger natural anagen entry in postdevelopmental hair follicle cycling.
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Proliferación Celular/genética , Regulación de la Expresión Génica/genética , Folículo Piloso/crecimiento & desarrollo , Factor de Transcripción STAT5/genética , Animales , Ciclo Celular/genética , Células Cultivadas , Folículo Piloso/citología , Humanos , Mediciones Luminiscentes , Ratones , Ratones Noqueados , Análisis por Micromatrices , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena de la Polimerasa/métodos , Transducción de SeñalRESUMEN
SerpinB2 (plasminogen activator inhibitor type 2) is constitutively expressed at high levels by differentiating keratinocytes in mice and humans; however, the physiological function of keratinocyte SerpinB2 remains unclear. Herein, we show that SerpinB2(-/-) mice are more susceptible to contact dermatitis after topical application of dinitrofluorobenzene, and show enhanced inflammatory lesions after topical applications of phorbol ester. Untreated SerpinB2(-/-) mice showed no overt changes in epithelial structure, and we were unable to find evidence for a role for keratinocyte SerpinB2 in regulating immunity, apoptosis, IL-1ß production, proteasomal activity, or wound healing. Instead, the phenotype was associated with impaired skin barrier function and a defective stratum corneum, with SerpinB2(-/-) mice showing increased transepidermal water loss, increased overt loss of stratum corneum in inflammatory lesions, and impaired stratum corneum thickening after phorbol ester treatment. Immunoblotting suggested that SerpinB2 (cross-linked into the cornified envelope) is present in the stratum corneum and retains the ability to form covalent inhibitory complexes with urokinase. Data suggest that the function of keratinocyte SerpinB2 is protection of the stratum corneum from proteolysis via inhibition of urokinase, thereby maintaining the integrity and barrier function of the stratum corneum, particularly during times of skin inflammation. Implications for studies involving genetically modified mice treated with topical agents and human dermatological conditions, such as contact dermatitis, are discussed.
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Dermatitis por Contacto/metabolismo , Inhibidor 2 de Activador Plasminogénico/metabolismo , Animales , Femenino , Immunoblotting , Inmunohistoquímica , Queratinocitos/metabolismo , Ratones , Ratones Noqueados , Inhibidor 2 de Activador Plasminogénico/deficiencia , Piel/metabolismo , Activador de Plasminógeno de Tipo Uroquinasa/metabolismoRESUMEN
Melanomas have high levels of genomic instability that can contribute to poor disease prognosis. Here, we report a novel defect of the ATM-dependent cell cycle checkpoint in melanoma cell lines that promotes genomic instability. In defective cells, ATM signalling to CHK2 is intact, but the cells are unable to maintain the cell cycle arrest due to elevated PLK1 driving recovery from the arrest. Reducing PLK1 activity recovered the ATM-dependent checkpoint arrest, and over-expressing PLK1 was sufficient to overcome the checkpoint arrest and increase genomic instability. Loss of the ATM-dependent checkpoint did not affect sensitivity to ionizing radiation demonstrating that this defect is distinct from ATM loss of function mutations. The checkpoint defective melanoma cell lines over-express PLK1, and a significant proportion of melanomas have high levels of PLK1 over-expression suggesting this defect is a common feature of melanomas. The inability of ATM to impose a cell cycle arrest in response to DNA damage increases genomic instability. This work also suggests that the ATM-dependent checkpoint arrest is likely to be defective in a higher proportion of cancers than previously expected.
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Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Puntos de Control del Ciclo Celular/efectos de la radiación , Inestabilidad Genómica/genética , Melanoma/genética , Melanoma/patología , Mutación/genética , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Quinasa de Punto de Control 2/metabolismo , Inestabilidad Genómica/efectos de la radiación , Humanos , Melanoma/enzimología , Mitosis/efectos de la radiación , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Radiación Ionizante , Regulación hacia Arriba/efectos de la radiación , Quinasa Tipo Polo 1RESUMEN
BACKGROUND: Infection with the Epstein-Barr virus (EBV) is associated with an increased risk of multiple sclerosis (MS). OBJECTIVE: We sought genetic loci influencing EBV nuclear antigen-1 (EBNA-1) IgG titers and hypothesized that they may play a role in MS risk. METHODS: We performed a genome-wide association study (GWAS) of anti-EBNA-1 IgG titers in 3599 individuals from an unselected twin family cohort, followed by a meta-analysis with data from an independent EBNA-1 GWAS. We then examined the shared polygenic risk between the EBNA-1 GWAS (effective sample size (Neff) = 5555) and a large MS GWAS (Neff = 15,231). RESULTS: We identified one locus of strong association within the human leukocyte antigen (HLA) region, of which the most significantly associated genotyped single nucleotide polymorphism (SNP) was rs2516049 (p = 4.11 × 10-9). A meta-analysis including data from another EBNA-1 GWAS in a cohort of Mexican-American families confirmed that rs2516049 remained the most significantly associated SNP (p = 3.32 × 10-20). By examining the shared polygenic risk, we show that the genetic risk for elevated anti-EBNA-1 titers is positively correlated with the development of MS, and that elevated EBNA-1 titers are not an epiphenomena secondary to MS. In the joint meta-analysis of EBNA-1 titers and MS, loci at 1p22.1, 3p24.1, 3q13.33, and 10p15.1 reached genome-wide significance (p < 5 × 10-8). CONCLUSIONS: Our results suggest that apart from the confirmed HLA region, the association of anti-EBNA-1 IgG titer with MS risk is also mediated through non-HLA genes, and that studies aimed at identifying genetic loci influencing EBNA immune response provides a novel opportunity to identify new and characterize existing genetic risk factors for MS.
Asunto(s)
Antígenos Nucleares del Virus de Epstein-Barr , Estudio de Asociación del Genoma Completo , Esclerosis Múltiple/etiología , Sitios Genéticos , Humanos , RiesgoRESUMEN
BACKGROUND: Peptide vaccination based on multiple T-cell epitopes can be used to target well-defined ethnic populations. Because the response to T-cell epitopes is restricted by HLA proteins, the HLA specificity of T-cell epitopes becomes a major consideration for epitope-based vaccine design. We have previously shown that CD4+ T-cell epitopes restricted by 95% of human MHC class II proteins can be predicted with high-specificity. METHODS: We describe here the integration of epitope prediction with population coverage and epitope selection algorithms. The population coverage assessment makes use of the Allele Frequency Net Database. We present the computational platform Predivac-2.0 for HLA class II-restricted epitope-based vaccine design, which accounts comprehensively for human genetic diversity. RESULTS: We validated the performance of the tool on the identification of promiscuous and immunodominant CD4+ T-cell epitopes from the human immunodeficiency virus (HIV) protein Gag. We further describe an application for epitope-based vaccine design in the context of emerging infectious diseases associated with Lassa, Nipah and Hendra viruses. Putative CD4+ T-cell epitopes were mapped on the surface glycoproteins of these pathogens and are good candidates to be experimentally tested, as they hold potential to provide cognate help in vaccination settings in their respective target populations. CONCLUSION: Predivac-2.0 is a novel approach in epitope-based vaccine design, particularly suited to be applied to virus-related emerging infectious diseases, because the geographic distributions of the viruses are well defined and ethnic populations in need of vaccination can be determined ("ethnicity-oriented approach"). Predivac-2.0 is accessible through the website http://predivac.biosci.uq.edu.au/.
Asunto(s)
Epítopos de Linfocito T/genética , Antígenos de Histocompatibilidad Clase II/genética , Grupos Raciales/genética , Vacunas de Subunidad/inmunología , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/inmunología , Vacunas contra el SIDA/inmunología , Linfocitos T CD4-Positivos/inmunología , Biología Computacional , Diseño de Fármacos , Epítopos de Linfocito T/inmunología , Glicoproteínas/inmunología , VIH-1/inmunología , Virus Hendra/inmunología , Infecciones por Henipavirus/inmunología , Infecciones por Henipavirus/prevención & control , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase I/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Humanos , Fiebre de Lassa/inmunología , Fiebre de Lassa/prevención & control , Virus Lassa/inmunología , Virus Nipah/inmunología , Proteínas del Envoltorio Viral/inmunologíaRESUMEN
Phosphorylation by the cyclin-dependent kinase 1 (Cdk1) adjacent to nuclear localization signals (NLSs) is an important mechanism of regulation of nucleocytoplasmic transport. However, no systematic survey has yet been performed in human cells to analyze this regulatory process, and the corresponding cell-cycle dynamics have not yet been investigated. Here, we focused on the human proteome and found that numerous proteins, previously not identified in this context, are associated with Cdk1-dependent phosphorylation sites adjacent to their NLSs. Interestingly, these proteins are involved in key regulatory events of DNA repair, epigenetics, or RNA editing and splicing. This finding indicates that cell-cycle dependent events of genome editing and gene expression profiling may be controlled by nucleocytoplasmic trafficking. For in-depth investigations, we selected a number of these proteins and analyzed how point mutations, expected to modify the phosphorylation ability of the NLS segments, perturb nucleocytoplasmic localization. In each case, we found that mutations mimicking hyper-phosphorylation abolish nuclear import processes. To understand the mechanism underlying these phenomena, we performed a video microscopy-based kinetic analysis to obtain information on cell-cycle dynamics on a model protein, dUTPase. We show that the NLS-adjacent phosphorylation by Cdk1 of human dUTPase, an enzyme essential for genomic integrity, results in dynamic cell cycle-dependent distribution of the protein. Non-phosphorylatable mutants have drastically altered protein re-import characteristics into the nucleus during the G1 phase. Our results suggest a dynamic Cdk1-driven mechanism of regulation of the nuclear proteome composition during the cell cycle.