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1.
Nature ; 606(7916): 999-1006, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35676472

RESUMEN

Large-scale human genetic data1-3 have shown that cancer mutations display strong tissue-selectivity, but how this selectivity arises remains unclear. Here, using experimental models, functional genomics and analyses of patient samples, we demonstrate that the lineage transcription factor paired box 8 (PAX8) is required for oncogenic signalling by two common genetic alterations that cause clear cell renal cell carcinoma (ccRCC) in humans: the germline variant rs7948643 at 11q13.3 and somatic inactivation of the von Hippel-Lindau tumour suppressor (VHL)4-6. VHL loss, which is observed in about 90% of ccRCCs, can lead to hypoxia-inducible factor 2α (HIF2A) stabilization6,7. We show that HIF2A is preferentially recruited to PAX8-bound transcriptional enhancers, including a pro-tumorigenic cyclin D1 (CCND1) enhancer that is controlled by PAX8 and HIF2A. The ccRCC-protective allele C at rs7948643 inhibits PAX8 binding at this enhancer and downstream activation of CCND1 expression. Co-option of a PAX8-dependent physiological programme that supports the proliferation of normal renal epithelial cells is also required for MYC expression from the ccRCC metastasis-associated amplicons at 8q21.3-q24.3 (ref. 8). These results demonstrate that transcriptional lineage factors are essential for oncogenic signalling and that they mediate tissue-specific cancer risk associated with somatic and inherited genetic variants.


Asunto(s)
Carcinogénesis , Neoplasias Renales , Factor de Transcripción PAX8 , Transducción de Señal , Alelos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Carcinogénesis/genética , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/patología , Ciclina D1/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Riñón/metabolismo , Riñón/patología , Neoplasias Renales/metabolismo , Neoplasias Renales/patología , Mutación , Factor de Transcripción PAX8/genética , Factor de Transcripción PAX8/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/genética
2.
Chembiochem ; 25(7): e202400047, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38350003

RESUMEN

The human enzyme 2'-deoxynucleoside 5'-phosphate N-hydrolase 1 (HsDNPH1) catalyses the hydrolysis of 5-hydroxymethyl-2'-deoxyuridine 5'-phosphate to generate 5-hydroxymethyluracil and 2-deoxyribose-5-phosphate via a covalent 5-phospho-2-deoxyribosylated enzyme intermediate. HsDNPH1 is a promising target for inhibitor development towards anticancer drugs. Here, site-directed mutagenesis of conserved active-site residues, followed by HPLC analysis of the reaction and steady-state kinetics are employed to reveal the importance of each of these residues in catalysis, and the reaction pH-dependence is perturbed by each mutation. Solvent deuterium isotope effects indicate no rate-limiting proton transfers. Crystal structures of D80N-HsDNPH1 in unliganded and substrate-bound states, and of unliganded D80A- and Y24F-HsDNPH1 offer atomic level insights into substrate binding and catalysis. The results reveal a network of hydrogen bonds involving the substrate and the E104-Y24-D80 catalytic triad and are consistent with a proposed mechanism whereby D80 is important for substrate positioning, for helping modulate E104 nucleophilicity, and as the general acid in the first half-reaction. Y24 positions E104 for catalysis and prevents a catalytically disruptive close contact between E104 and D80.


Asunto(s)
Fosfatos , Humanos , Sitios de Unión/genética , Catálisis , Dominio Catalítico , Concentración de Iones de Hidrógeno , Cinética
3.
Anal Bioanal Chem ; 416(18): 4015-4028, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38780655

RESUMEN

A workflow has been evaluated that utilizes a single tissue section to obtain spatially co-registered, molecular, and phenotypical information suitable for AI-enabled image analysis. Desorption electrospray ionization mass spectrometry imaging (DESI-MSI) was used to obtain molecular information followed by conventional histological staining and immunolabelling. The impact of varying DESI-MSI conditions (e.g., heated transfer line (HTL) temperature, scan rate, acquisition time) on the detection of small molecules and lipids as well as on tissue integrity crucial for integration into typical clinical pathology workflows was assessed in human kidney. Increasing the heated transfer line temperature from 150 to 450 °C resulted in a 1.8-fold enhancement in lipid signal at a scan rate of 10 scans/s, while preserving histological features. Moreover, increasing the acquisition speed to 30 scans/s yielded superior lipid signal when compared to 10 scans/s at 150 °C. Tissue morphology and protein epitopes remained intact allowing full histological assessment and further multiplex phenotyping by immunofluorescence (mIF) and immunohistochemistry (mIHC) of the same section. The successful integration of the workflow incorporating DESI-MSI, H&E, and immunolabelling on a single tissue section revealed an accumulation of ascorbic acid in regions of focal chronic inflammatory cell infiltrate within non-cancerous kidney tissue. Additionally, a strong positive correlation between PI 38:3 and proliferating cells was observed in clear cell renal cell carcinoma (ccRCC) showing the utility of this approach in uncovering molecular associations in disease pathology.


Asunto(s)
Carcinoma de Células Renales , Proliferación Celular , Neoplasias Renales , Imagen Multimodal , Espectrometría de Masa por Ionización de Electrospray , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/diagnóstico por imagen , Humanos , Neoplasias Renales/metabolismo , Neoplasias Renales/patología , Neoplasias Renales/diagnóstico por imagen , Espectrometría de Masa por Ionización de Electrospray/métodos , Imagen Multimodal/métodos , Fenotipo , Riñón/metabolismo , Riñón/patología
4.
Biochemistry ; 62(17): 2658-2668, 2023 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-37582341

RESUMEN

The enzyme 2'-deoxynucleoside 5'-phosphate N-hydrolase 1 (DNPH1) catalyzes the N-ribosidic bond cleavage of 5-hydroxymethyl-2'-deoxyuridine 5'-monophosphate to generate 2-deoxyribose 5-phosphate and 5-hydroxymethyluracil. DNPH1 accepts other 2'-deoxynucleoside 5'-monophosphates as slow-reacting substrates. DNPH1 inhibition is a promising strategy to overcome resistance to and potentiate anticancer poly(ADP-ribose) polymerase inhibitors. We solved the crystal structure of unliganded human DNPH1 and took advantage of the slow reactivity of 2'-deoxyuridine 5'-monophosphate (dUMP) as a substrate to obtain a crystal structure of the DNPH1:dUMP Michaelis complex. In both structures, the carboxylate group of the catalytic Glu residue, proposed to act as a nucleophile in covalent catalysis, forms an apparent low-barrier hydrogen bond with the hydroxyl group of a conserved Tyr residue. The crystal structures are supported by functional data, with liquid chromatography-mass spectrometry analysis showing that DNPH1 incubation with dUMP leads to slow yet complete hydrolysis of the substrate. A direct UV-vis absorbance-based assay allowed characterization of DNPH1 kinetics at low dUMP concentrations. A bell-shaped pH-rate profile indicated that acid-base catalysis is operational and that for maximum kcat/KM, two groups with an average pKa of 6.4 must be deprotonated, while two groups with an average pKa of 8.2 must be protonated. A modestly inverse solvent viscosity effect rules out diffusional processes involved in dUMP binding to and possibly uracil release from the enzyme as rate limiting to kcat/KM. Solvent deuterium isotope effects on kcat/KM and kcat were inverse and unity, respectively. A reaction mechanism for dUMP hydrolysis is proposed.


Asunto(s)
Desoxiuridina , Hidrolasas , Humanos , Hidrólisis , Catálisis , Solventes , Fosfatos , Cinética , Concentración de Iones de Hidrógeno
5.
Hum Mol Genet ; 30(19): 1863-1880, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34100083

RESUMEN

Abnormally elevated expression of the imprinted PHLDA2 gene has been reported in the placenta of human babies that are growth restricted in utero in several studies. We previously modelled this gene alteration in mice and found that just 2-fold increased expression of Phlda2 resulted in placental endocrine insufficiency. In addition, elevated Phlda2 was found to drive fetal growth restriction (FGR) of transgenic offspring and impaired maternal care by their wildtype mothers. Being born small and being exposed to suboptimal maternal care have both been associated with the increased risk of mental health disorders in human populations. In the current study we probed behavioural consequences of elevated Phlda2 for the offspring. We discovered increased anxiety-like behaviours, deficits in cognition and atypical social behaviours, with the greatest impact on male offspring. Subsequent analysis revealed alterations in the transcriptome of the adult offspring hippocampus, hypothalamus and amygdala, regions consistent with these behavioural observations. The inclusion of a group of fully wildtype controls raised in a normal maternal environment allowed us to attribute behavioural and molecular alterations to the adverse maternal environment induced by placental endocrine insufficiency rather than the specific gene change of elevated Phlda2. Our work demonstrates that a highly common alteration reported in human FGR is associated with negative behavioural outcomes later in life. Importantly, we also establish the experimental paradigm that placental endocrine insufficiency can program atypical behaviour in offspring highlighting the under-appreciated role of placental endocrine insufficiency in driving disorders of later life behaviour.


Asunto(s)
Retardo del Crecimiento Fetal , Placenta , Animales , Ansiedad/genética , Cognición , Femenino , Retardo del Crecimiento Fetal/genética , Masculino , Ratones , Placenta/metabolismo , Embarazo , Conducta Social
6.
Am J Respir Cell Mol Biol ; 66(2): 196-205, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34710339

RESUMEN

Immunopathology occurs in the lung and spleen in fatal coronavirus disease (COVID-19), involving monocytes/macrophages and plasma cells. Antiinflammatory therapy reduces mortality, but additional therapeutic targets are required. We aimed to gain mechanistic insight into COVID-19 immunopathology by targeted proteomic analysis of pulmonary and splenic tissues. Lung parenchymal and splenic tissue was obtained from 13 postmortem examinations of patients with fatal COVID-19. Control tissue was obtained from cancer resection samples (lung) and deceased organ donors (spleen). Protein was extracted from tissue by phenol extraction. Olink multiplex immunoassay panels were used for protein detection and quantification. Proteins with increased abundance in the lung included MCP-3, antiviral TRIM21, and prothrombotic TYMP. OSM and EN-RAGE/S100A12 abundance was correlated and associated with inflammation severity. Unsupervised clustering identified "early viral" and "late inflammatory" clusters with distinct protein abundance profiles, and differences in illness duration before death and presence of viral RNA. In the spleen, lymphocyte chemotactic factors and CD8A were decreased in abundance, and proapoptotic factors were increased. B-cell receptor signaling pathway components and macrophage colony stimulating factor (CSF-1) were also increased. Additional evidence for a subset of host factors (including DDX58, OSM, TYMP, IL-18, MCP-3, and CSF-1) was provided by overlap between 1) differential abundance in spleen and lung tissue; 2) meta-analysis of existing datasets; and 3) plasma proteomic data. This proteomic analysis of lung parenchymal and splenic tissue from fatal COVID-19 provides mechanistic insight into tissue antiviral responses, inflammation and disease stages, macrophage involvement, pulmonary thrombosis, splenic B-cell activation, and lymphocyte depletion.


Asunto(s)
COVID-19/inmunología , Regulación de la Expresión Génica/inmunología , Pulmón/inmunología , SARS-CoV-2/inmunología , Bazo/inmunología , Anciano , Anciano de 80 o más Años , Autopsia , Femenino , Humanos , Inflamación/inmunología , Masculino , Proteómica
7.
Mov Disord ; 37(3): 613-619, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34766658

RESUMEN

BACKGROUND: The risk of graft-induced dyskinesias (GIDs) presents a major challenge in progressing cell transplantation as a therapy for Parkinson's disease. Current theories implicate the presence of grafted serotonin neurons, hotspots of dopamine release, neuroinflammation and established levodopa-induced dyskinesia. OBJECTIVE: To elucidate the mechanisms of GIDs. METHODS: Neonatally desensitized, dopamine denervated rats received intrastriatal grafts of human embryonic stem cells (hESCs) differentiated into either ventral midbrain dopaminergic progenitor (vmDA) (n = 15) or ventral forebrain cells (n = 14). RESULTS: Of the eight rats with surviving grafts, two vmDA rats developed chronic spontaneous GIDs, which were observed at 30 weeks post-transplantation. GIDs were inhibited by D2 -like receptor antagonists and not affected by 5-HT1A/1B/5-HT6 agonists/antagonists. Grafts in GID rats showed more microglial activation and lacked serotonin neurons. CONCLUSIONS: These findings argue against current thinking that rats do not develop spontaneous GID and that serotonin neurons are causative, rather indicating that GID can be induced in rats by hESC-derived dopamine grafts and, critically, can occur independently of both previous levodopa exposure and grafted serotonin neurons. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Asunto(s)
Discinesia Inducida por Medicamentos , Discinesias , Enfermedad de Parkinson , Animales , Antiparkinsonianos/efectos adversos , Dopamina , Discinesia Inducida por Medicamentos/etiología , Discinesias/complicaciones , Humanos , Levodopa/efectos adversos , Neuronas , Enfermedad de Parkinson/complicaciones , Ratas , Ratas Sprague-Dawley , Serotonina
8.
Am J Respir Crit Care Med ; 203(2): 192-201, 2021 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-33217246

RESUMEN

Rationale: In life-threatening coronavirus disease (COVID-19), corticosteroids reduce mortality, suggesting that immune responses have a causal role in death. Whether this deleterious inflammation is primarily a direct reaction to the presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or an independent immunopathologic process is unknown.Objectives: To determine SARS-CoV-2 organotropism and organ-specific inflammatory responses and the relationships among viral presence, inflammation, and organ injury.Methods: Tissue was acquired from 11 detailed postmortem examinations. SARS-CoV-2 organotropism was mapped by using multiplex PCR and sequencing, with cellular resolution achieved by in situ viral S (spike) protein detection. Histologic evidence of inflammation was quantified from 37 anatomic sites, and the pulmonary immune response was characterized by using multiplex immunofluorescence.Measurements and Main Results: Multiple aberrant immune responses in fatal COVID-19 were found, principally involving the lung and reticuloendothelial system, and these were not clearly topologically associated with the virus. Inflammation and organ dysfunction did not map to the tissue and cellular distribution of SARS-CoV-2 RNA and protein between or within tissues. An arteritis was identified in the lung, which was further characterized as a monocyte/myeloid-rich vasculitis, and occurred together with an influx of macrophage/monocyte-lineage cells into the pulmonary parenchyma. In addition, stereotyped abnormal reticuloendothelial responses, including excessive reactive plasmacytosis and iron-laden macrophages, were present and dissociated from viral presence in lymphoid tissues.Conclusions: Tissue-specific immunopathology occurs in COVID-19, implicating a significant component of the immune-mediated, virus-independent immunopathologic process as a primary mechanism in severe disease. Our data highlight novel immunopathologic mechanisms and validate ongoing and future efforts to therapeutically target aberrant macrophage and plasma-cell responses as well as promote pathogen tolerance in COVID-19.


Asunto(s)
COVID-19/inmunología , Inflamación/virología , Pulmón/inmunología , Insuficiencia Multiorgánica/virología , SARS-CoV-2/inmunología , Anciano , Anciano de 80 o más Años , Autopsia , Biopsia , COVID-19/patología , COVID-19/virología , Prueba de Ácido Nucleico para COVID-19 , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Inflamación/inmunología , Inflamación/patología , Pulmón/patología , Pulmón/virología , Masculino , Insuficiencia Multiorgánica/inmunología , Insuficiencia Multiorgánica/patología , SARS-CoV-2/patogenicidad , Índice de Severidad de la Enfermedad
9.
Lancet Oncol ; 22(10): e435-e445, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34592193

RESUMEN

The 2013 SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) Statement provides evidence-based recommendations for the minimum content to be included in a clinical trial protocol. Assessment of biospecimens is often required for trial eligibility or as part of an outcome evaluation, and precision molecular approaches are increasingly used in trial design. However, cellular and molecular pathology practices within trials have not been codified or formalised. We developed international consensus reporting guidelines for cellular and molecular pathology content in clinical trial protocols (the SPIRIT-Path extension) using an international Delphi process, which assesses candidate items generated from a previous systematic review, followed by an expert consensus meeting. 74 individuals from five continents responded, including clinicians, statisticians, laboratory scientists, patient advocates, funders, industry representatives, journal editors, and regulators. The SPIRIT-Path guidelines recommend 14 additional items (seven extensions to the SPIRIT checklist and seven elaborations) that should be addressed in trial protocols containing pathology content, alongside the SPIRIT 2013 Statement items. SPIRIT-Path recommends that protocols should document the individuals, processes, and standards for all cellular and molecular pathology components of the trial, including all stages of the specimen pathway and any digital pathology methods, with specific consideration of the value of trial data and biological tissues for additional translational studies.


Asunto(s)
Protocolos de Ensayos Clínicos como Asunto , Ensayos Clínicos como Asunto/normas , Patología Molecular/normas , Proyectos de Investigación/normas , Lista de Verificación , Consenso , Técnica Delphi , Humanos
10.
Stat Med ; 38(8): 1421-1441, 2019 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-30488481

RESUMEN

Diagnosis and prognosis of cancer are informed by the architecture inherent in cancer patient tissue sections. This architecture is typically identified by pathologists, yet advances in computational image analysis facilitate quantitative assessment of this structure. In this article, we develop a spatial point process approach to describe patterns in cell distribution within tissue samples taken from colorectal cancer (CRC) patients. In particular, our approach is centered on the Palm intensity function. This leads to taking an approximate-likelihood technique in fitting point processes models. We consider two Neyman-Scott point processes and a void process, fitting these point process models to the CRC patient data. We find that the parameter estimates of these models may be used to quantify the spatial arrangement of cells. Importantly, we observe characteristic differences in the spatial arrangement of cells between patients who died from CRC and those alive at follow up.


Asunto(s)
Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/patología , Algoritmos , Interpretación Estadística de Datos , Humanos , Pronóstico
11.
Cardiovasc Drugs Ther ; 32(6): 601-610, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30446883

RESUMEN

PURPOSE: Compare medical expenditures among adults with statin-associated adverse effects (SAAE) and high statin adherence (HSA) following myocardial infarction (MI). METHODS: We analyzed expenditures in 2016 US dollars among Medicare beneficiaries with SAAE (n = 1741) and HSA (n = 55,567) who were ≥ 66 years of age and initiated moderate/high-intensity statins following an MI in 2007-2013. SAAE were identified through a claims-based algorithm, which included down-titrating statins and initiating ezetimibe, switching to ezetimibe monotherapy, having a rhabdomyolysis or antihyperlipidemic adverse event followed by statin down-titration or discontinuation, or switching between ≥ 3 statin types within 365 days following MI. HSA was defined by having a statin available to take for ≥ 80% of the days in the 365 days following MI. RESULTS: Expenditures among beneficiaries with SAAE and HSA were $40,776 (95% CI $38,329-$43,223) and $26,728 ($26,482-$26,974), respectively, in the 365 days following MI, and $34,238 ($31,396-$37,080) and $29,053 ($28,605-$29,500), respectively, for every year after the first 365 days. Multivariable-adjusted ratios comparing expenditures among beneficiaries with SAAE versus HSA in the first 365 days and after the first 365 days following MI were 1.51 (95% CI 1.43-1.59) and 1.23 (1.12-1.34), respectively. Inpatient and outpatient expenditures were higher among beneficiaries with SAAE versus HSA during and after the first 365 days following MI. Compared to beneficiaries with HSA, medication expenditures among those with SAAE were similar in the 365 days following MI, but higher afterwards. Other medical expenditures were higher among beneficiaries with SAAE versus HSA. CONCLUSION: SAAE are associated with increased expenditures following MI compared with HSA.


Asunto(s)
Costos de los Medicamentos , Gastos en Salud , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/economía , Beneficios del Seguro/economía , Medicare/economía , Cumplimiento de la Medicación , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/economía , Anciano , Anciano de 80 o más Años , Atención Ambulatoria , Sustitución de Medicamentos/economía , Femenino , Costos de Hospital , Humanos , Masculino , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos/epidemiología
12.
BMC Med ; 15(1): 118, 2017 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-28648142

RESUMEN

BACKGROUND: Metastatic clear cell renal cell cancer (mccRCC) portends a poor prognosis and urgently requires better clinical tools for prognostication as well as for prediction of response to treatment. Considerable investment in molecular risk stratification has sought to overcome the performance ceiling encountered by methods restricted to traditional clinical parameters. However, replication of results has proven challenging, and intratumoural heterogeneity (ITH) may confound attempts at tissue-based stratification. METHODS: We investigated the influence of confounding ITH on the performance of a novel molecular prognostic model, enabled by pathologist-guided multiregion sampling (n = 183) of geographically separated mccRCC cohorts from the SuMR trial (development, n = 22) and the SCOTRRCC study (validation, n = 22). Tumour protein levels quantified by reverse phase protein array (RPPA) were investigated alongside clinical variables. Regularised wrapper selection identified features for Cox multivariate analysis with overall survival as the primary endpoint. RESULTS: The optimal subset of variables in the final stratification model consisted of N-cadherin, EPCAM, Age, mTOR (NEAT). Risk groups from NEAT had a markedly different prognosis in the validation cohort (log-rank p = 7.62 × 10-7; hazard ratio (HR) 37.9, 95% confidence interval 4.1-353.8) and 2-year survival rates (accuracy = 82%, Matthews correlation coefficient = 0.62). Comparisons with established clinico-pathological scores suggest favourable performance for NEAT (Net reclassification improvement 7.1% vs International Metastatic Database Consortium score, 25.4% vs Memorial Sloan Kettering Cancer Center score). Limitations include the relatively small cohorts and associated wide confidence intervals on predictive performance. Our multiregion sampling approach enabled investigation of NEAT validation when limiting the number of samples analysed per tumour, which significantly degraded performance. Indeed, sample selection could change risk group assignment for 64% of patients, and prognostication with one sample per patient performed only slightly better than random expectation (median logHR = 0.109). Low grade tissue was associated with 3.5-fold greater variation in predicted risk than high grade (p = 0.044). CONCLUSIONS: This case study in mccRCC quantitatively demonstrates the critical importance of tumour sampling for the success of molecular biomarker studies research where ITH is a factor. The NEAT model shows promise for mccRCC prognostication and warrants follow-up in larger cohorts. Our work evidences actionable parameters to guide sample collection (tumour coverage, size, grade) to inform the development of reproducible molecular risk stratification methods.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma de Células Renales/genética , Heterogeneidad Genética , Neoplasias Renales/genética , Adulto , Anciano , Carcinoma de Células Renales/fisiopatología , Estudios de Cohortes , Femenino , Humanos , Neoplasias Renales/patología , Neoplasias Renales/fisiopatología , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Análisis por Matrices de Proteínas , Tasa de Supervivencia
13.
BMC Cancer ; 17(1): 9, 2017 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-28052770

RESUMEN

BACKGROUND: There is an unmet clinical need for better prognostic and diagnostic tools for renal cell carcinoma (RCC). METHODS: Human Protein Atlas data resources, including the transcriptomes and proteomes of normal and malignant human tissues, were searched for RCC-specific proteins and cubilin (CUBN) identified as a candidate. Patient tissue representing various cancer types was constructed into a tissue microarray (n = 940) and immunohistochemistry used to investigate the specificity of CUBN expression in RCC as compared to other cancers. Two independent RCC cohorts (n = 181; n = 114) were analyzed to further establish the sensitivity of CUBN as RCC-specific marker and to explore if the fraction of RCCs lacking CUBN expression could predict differences in patient survival. RESULTS: CUBN was identified as highly RCC-specific protein with 58% of all primary RCCs staining positive for CUBN using immunohistochemistry. In venous tumor thrombi and metastatic lesions, the frequency of CUBN expression was increasingly lost. Clear cell RCC (ccRCC) patients with CUBN positive tumors had a significantly better prognosis compared to patients with CUBN negative tumors, independent of T-stage, Fuhrman grade and nodal status (HR 0.382, CI 0.203-0.719, P = 0.003). CONCLUSIONS: CUBN expression is highly specific to RCC and loss of the protein is significantly and independently associated with poor prognosis. CUBN expression in ccRCC provides a promising positive prognostic indicator for patients with ccRCC. The high specificity of CUBN expression in RCC also suggests a role as a new diagnostic marker in clinical cancer differential diagnostics to confirm or rule out RCC.


Asunto(s)
Carcinoma de Células Renales/patología , Neoplasias Renales/patología , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/metabolismo , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/metabolismo , Bases de Datos Genéticas , Progresión de la Enfermedad , Regulación hacia Abajo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Renales/genética , Neoplasias Renales/metabolismo , Ganglios Linfáticos/patología , Masculino , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico
14.
Prostate ; 76(12): 1078-87, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27121847

RESUMEN

BACKGROUND: Prostate cancer (PCa) diagnosis is challenging because efforts for effective, timely treatment of men with significant cancer typically result in over-diagnosis and repeat biopsies. The presence or absence of epigenetic aberrations, more specifically DNA-methylation of GSTP1, RASSF1, and APC in histopathologically negative prostate core biopsies has resulted in an increased negative predictive value (NPV) of ∼90% and thus could lead to a reduction of unnecessary repeat biopsies. Here, it is investigated whether, in methylation-positive men, DNA-methylation intensities could help to identify those men harboring high-grade (Gleason score ≥7) PCa, resulting in an improved positive predictive value. METHODS: Two cohorts, consisting of men with histopathologically negative index biopsies, followed by a positive or negative repeat biopsy, were combined. EpiScore, a methylation intensity algorithm was developed in methylation-positive men, using area under the curve of the receiver operating characteristic as metric for performance. Next, a risk score was developed combining EpiScore with traditional clinical risk factors to further improve the identification of high-grade (Gleason Score ≥7) cancer. RESULTS: Compared to other risk factors, detection of DNA-methylation in histopathologically negative biopsies was the most significant and important predictor of high-grade cancer, resulting in a NPV of 96%. In methylation-positive men, EpiScore was significantly higher for those with high-grade cancer detected upon repeat biopsy, compared to those with either no or low-grade cancer. The risk score resulted in further improvement of patient risk stratification and was a significantly better predictor compared to currently used metrics as PSA and the prostate cancer prevention trial (PCPT) risk calculator (RC). A decision curve analysis indicated strong clinical utility for the risk score as decision-making tool for repeat biopsy. CONCLUSIONS: Low DNA-methylation levels in PCa-negative biopsies led to a NPV of 96% for high-grade cancer. The risk score, comprising DNA-methylation intensity and traditional clinical risk factors, improved the identification of men with high-grade cancer, with a maximum avoidance of unnecessary repeat biopsies. This risk score resulted in better patient risk stratification and significantly outperformed current risk prediction models such as PCPTRC and PSA. The risk score could help to identify patients with histopathologically negative biopsies harboring high-grade PCa. Prostate 76:1078-1087, 2016. © 2016 The Authors. The Prostate Published by Wiley Periodicals, Inc.


Asunto(s)
Biopsia con Aguja , Metilación de ADN , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Poliposis Adenomatosa del Colon/genética , Anciano , Epigénesis Genética , Reacciones Falso Negativas , Gutatión-S-Transferasa pi/genética , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Próstata/patología , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/diagnóstico , Factores de Riesgo , Proteínas Supresoras de Tumor/genética
15.
Br J Cancer ; 114(8): 905-16, 2016 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-27031849

RESUMEN

BACKGROUND: The natural polyphenol myricetin induces cell cycle arrest and apoptosis in preclinical cancer models. We hypothesised that myricetin-derived flavonoids with enhanced redox properties, improved cell uptake and mitochondrial targeting might have increased potential as antitumour agents. METHODS: We studied the effect of a second-generation flavonoid analogue Oncamex in a panel of seven breast cancer cell lines, applying western blotting, gene expression analysis, fluorescence microscopy and immunohistochemistry of xenograft tissue to investigate its mechanism of action. RESULTS: Proliferation assays showed that Oncamex treatment for 8 h reduced cell viability and induced cytotoxicity and apoptosis, concomitant with increased caspase activation. Microarray analysis showed that Oncamex was associated with changes in the expression of genes controlling cell cycle and apoptosis. Fluorescence microscopy showed the compound's mitochondrial targeting and reactive oxygen species-modulating properties, inducing superoxide production at concentrations associated with antiproliferative effects. A preliminary in vivo study in mice implanted with the MDA-MB-231 breast cancer xenograft showed that Oncamex inhibited tumour growth, reducing tissue viability and Ki-67 proliferation, with no signs of untoward effects on the animals. CONCLUSIONS: Oncamex is a novel flavonoid capable of specific mitochondrial delivery and redox modulation. It has shown antitumour activity in preclinical models of breast cancer, supporting the potential of this prototypic candidate for its continued development as an anticancer agent.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Flavonoides/farmacología , Animales , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/metabolismo , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Femenino , Humanos , Células MCF-7 , Ratones , Mitocondrias/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
16.
BMC Cancer ; 16: 205, 2016 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-26964739

RESUMEN

BACKGROUND: The dynamic changes that occur in protein expression after treatment of a cancer in vivo are poorly described. In this study we measure the effect of chemotherapy over time on the expression of a panel of proteins in ovarian cancer xenograft models. The objective was to identify phosphoprotein and other protein changes indicative of pathway activation that might link with drug response. METHODS: Two xenograft models, platinum-responsive OV1002 and platinum-unresponsive HOX424, were used. Treatments were carboplatin and carboplatin-paclitaxel. Expression of 49 proteins over 14 days post treatment was measured by quantitative immunofluorescence and analysed by AQUA. RESULTS: Carboplatin treatment in the platinum-sensitive OV1002 model triggered up-regulation of cell cycle, mTOR and DDR pathways, while at late time points WNT, invasion, EMT and MAPK pathways were modulated. Estrogen receptor-alpha (ESR1) and ERBB pathways were down-regulated early, within 24 h from treatment administration. Combined carboplatin-paclitaxel treatment triggered a more extensive response in the OV1002 model modulating expression of 23 of 49 proteins. Therefore the cell cycle and DDR pathways showed similar or more pronounced changes than with carboplatin alone. In addition to expression of pS6 and pERK increasing, components of the AKT pathway were modulated with pAKT increasing while its regulator PTEN was down-regulated early. WNT signaling, EMT and invasion markers were modulated at later time points. Additional pathways were also observed with the NFκB and JAK/STAT pathways being up-regulated. ESR1 was down-regulated as was HER4, while further protein members of the ERBB pathway were upregulated late. By contrast, in the carboplatin-unresponsive HOX 424 xenograft, carboplatin only modulated expression of MLH1 while carboplatin-paclitaxel treatment modulated ESR1 and pMET. CONCLUSIONS: Thirteen proteins were modulated by carboplatin and a more robust set of changes by carboplatin-paclitaxel. Early changes included DDR and cell cycle regulatory proteins associating with tumor volume changes, as expected. Changes in ESR1 and ERBB signaling were also observed. Late changes included components of MAPK signaling, EMT and invasion markers and coincided in time with reversal in tumor volume reduction. These results suggest potential therapeutic roles for inhibitors of such pathways that may prolong chemotherapeutic effects.


Asunto(s)
Proteínas de Neoplasias/biosíntesis , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Fosfoproteínas/biosíntesis , Animales , Protocolos de Quimioterapia Combinada Antineoplásica , Apoptosis/efectos de los fármacos , Carboplatino/administración & dosificación , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ratones , Proteínas de Neoplasias/genética , Neoplasias Ováricas/patología , Paclitaxel/administración & dosificación , Fosfoproteínas/genética , Pronóstico , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/biosíntesis , Ensayos Antitumor por Modelo de Xenoinjerto
17.
J Am Acad Dermatol ; 75(1): 77-82.e7, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27206759

RESUMEN

BACKGROUND: New psoriasis therapies have increased the ability to achieve skin clearance. However, insufficient evidence exists on the impact of total skin clearance from the patient perspective. OBJECTIVE: We sought to determine if complete skin clearance is clinically meaningful compared with treatment responses without clearance. METHODS: Pooled data from 3 phase-III trials were used to compare results for patients with complete skin clearance (Psoriasis Area and Severity Index [PASI] 100 or static Physician Global Assessment score 0) with patients without complete skin clearance (PASI 75 to <100 or static Physician Global Assessment score 1) based on Psoriasis Symptom Inventory and Dermatology Life Quality Index. RESULTS: Percentages of patients with Psoriasis Symptom Inventory score 0 were 45% for those achieving PASI 100 and 8% for PASI 75 to <100 (P < .001). Respective percentages with Dermatology Life Quality Index score 0/1 were 80% and 55% (P < .001). PASI 100 resulted in incremental improvement over PASI 90 to <100 (incremental differences of 28% for Psoriasis Symptom Inventory score 0 and 18% for Dermatology Life Quality Index score 0). Similar results were observed for static Physician Global Assessment scores 0 versus 1. CONCLUSIONS: Complete skin clearance represents a clinically meaningful end point and outcome for patients, reflected in experiences of no psoriasis symptoms and no impairment on health-related quality of life.


Asunto(s)
Psoriasis/tratamiento farmacológico , Psoriasis/psicología , Calidad de Vida , Adulto , Ensayos Clínicos Fase III como Asunto , Eritema/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prurito/etiología , Psoriasis/complicaciones , Inducción de Remisión , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
18.
J Cell Biochem ; 116(3): 476-85, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25358258

RESUMEN

MBD4 is the only methyl-CpG binding protein that possesses a C-terminal glycosylase domain. It has been associated with a number of nuclear pathways including DNA repair, DNA damage response, the initiation of apoptosis, transcriptional repression, and DNA demethylation. However, the precise contribution of MBD4 to these processes in development and relevant diseases remains elusive. We identified UHRF1 and USP7 as two new interaction partners for MBD4. Both UHRF1, a E3 ubiquitin ligase, and USP7, a de-ubiquinating enzyme, regulate the stability of the DNA maintenance methyltransferase, Dnmt1. The ability of MBD4 to directly interact with and recruit USP7 to chromocenters implicates it as an additional factor that can potentially regulate Dnmt1 activity during cell proliferation.


Asunto(s)
Endodesoxirribonucleasas/metabolismo , Heterocromatina/metabolismo , Ubiquitina Tiolesterasa/metabolismo , Animales , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Replicación del ADN , Proteínas Fluorescentes Verdes/metabolismo , Células HEK293 , Humanos , Ratones , Unión Proteica , Ubiquitina-Proteína Ligasas , Peptidasa Específica de Ubiquitina 7
19.
Genome Res ; 22(3): 467-77, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22106369

RESUMEN

The discovery of substantial amounts of 5-hydroxymethylcytosine (5hmC), formed by the oxidation of 5-methylcytosine (5mC), in various mouse tissues and human embryonic stem (ES) cells has necessitated a reevaluation of our knowledge of 5mC/5hmC patterns and functions in mammalian cells. Here, we investigate the tissue specificity of both the global levels and locus-specific distribution of 5hmC in several human tissues and cell lines. We find that global 5hmC content of normal human tissues is highly variable, does not correlate with global 5mC content, and decreases rapidly as cells from normal tissue adapt to cell culture. Using tiling microarrays to map 5hmC levels in DNA from normal human tissues, we find that 5hmC patterns are tissue specific; unsupervised hierarchical clustering based solely on 5hmC patterns groups independent biological samples by tissue type. Moreover, in agreement with previous studies, we find 5hmC associated primarily, but not exclusively, with the body of transcribed genes, and that within these genes 5hmC levels are positively correlated with transcription levels. However, using quantitative 5hmC-qPCR, we find that the absolute levels of 5hmC for any given gene are primarily determined by tissue type, gene expression having a secondary influence on 5hmC levels. That is, a gene transcribed at a similar level in several different tissues may have vastly different levels of 5hmC (>20-fold) dependent on tissue type. Our findings highlight tissue type as a major modifier of 5hmC levels in expressed genes and emphasize the importance of using quantitative analyses in the study of 5hmC levels.


Asunto(s)
Citosina/análogos & derivados , ADN/química , Regulación de la Expresión Génica , Transcripción Genética , 5-Metilcitosina/análogos & derivados , Animales , Línea Celular , Células Cultivadas , Mapeo Cromosómico , Análisis por Conglomerados , Citosina/análisis , Metilación de ADN , Células Madre Embrionarias/metabolismo , Epigénesis Genética , Perfilación de la Expresión Génica , Sitios Genéticos , Humanos , Ratones , Proteínas Nucleares/genética , Especificidad de Órganos/genética , Regiones Promotoras Genéticas , Proteínas de Unión al ARN
20.
Clin Exp Rheumatol ; 33(3): 297-301, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25738333

RESUMEN

OBJECTIVES: The purpose of this analysis was to examine discontinuation and reasons for discontinuation from disease-modifying anti-rheumatic (DMARD) therapies in the RADIUS 2 registry, a long-term, open-label, observational study of patients with moderate to severe rheumatoid arthritis (RA). METHODS: Patients who participated in RADIUS 2 initiated etanercept (ETN) therapy at study entry and were followed for 5 years. In this post hoc analysis, patients who had received ETN continuously from entry to month 4 were categorised by treatment at month 4: ETN monotherapy, ETN+methotrexate (MTX), ETN+MTX+other DMARDs (OTH), or ETN+OTH. Outcomes were assessed at month 4 and at the time of any subsequent treatment change, and included Clinical Disease Activity Index (CDAI) and Health Assessment Questionnaire Disability Index (HAQ-DI). RESULTS: Of 3,484 patients analysed (982 ETN; 1,356 ETN+MTX; 537 ETN+MTX+OTH; 609 ETN+OTH), baseline demographic and clinical characteristics were similar across treatments. No treatment change occurred in 62.3%, 49.9%, 33.3%, and 37.1% of ETN, ETN+MTX, ETN+MTX+OTH, and ETN+OTH patients, respectively. The mean time on therapy from month 4 was longer for patients receiving ETN (23.3 months) or ETN+MTX (23.7 months) than those receiving ETN+MTX+OTH (18.0 months) or ETN+OTH (18.3 months). The greatest improvements in CDAI and HAQ-DI were seen in patients who continued on ETN. The most common reasons for discontinuing DMARD therapy were cost and ineffective treatment. CONCLUSIONS: Most patients who had received ≥4 months of ETN continued on ETN throughout the 5-year observation period. Patients with greatest clinical and disability improvements tended to continue on ETN.


Asunto(s)
Antirreumáticos/administración & dosificación , Artritis Reumatoide/tratamiento farmacológico , Inmunoglobulina G/administración & dosificación , Metotrexato/administración & dosificación , Receptores del Factor de Necrosis Tumoral/administración & dosificación , Adulto , Antirreumáticos/efectos adversos , Antirreumáticos/economía , Artritis Reumatoide/diagnóstico , Artritis Reumatoide/economía , Análisis Costo-Beneficio , Evaluación de la Discapacidad , Esquema de Medicación , Costos de los Medicamentos , Quimioterapia Combinada , Etanercept , Femenino , Humanos , Inmunoglobulina G/efectos adversos , Inmunoglobulina G/economía , Masculino , Metotrexato/efectos adversos , Metotrexato/economía , Persona de Mediana Edad , Estudios Prospectivos , Sistema de Registros , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos
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