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1.
Lab Invest ; 104(1): 100284, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37949357

RESUMO

Claudin 18.2 (CLDN18.2), the dominant isoform of CLDN18 in gastric tissues, is a highly specific tight junction protein of the gastric mucosa with variably retained expressions in gastric and gastroesophageal junction cancers. Additionally, CLDN18.2-targeted treatment with zolbetuximab, in combination with chemotherapy, has recently been assessed in 2 phase-III studies of patients with HER2-negative, locally advanced, unresectable, or metastatic gastric or gastroesophageal junction adenocarcinoma. These trials used the investigational VENTANA CLDN18 (43-14A) RxDx immunohistochemistry (IHC) assay on the Ventana BenchMark platform to identify patients eligible for CLDN18.2-targeted treatment. We report the findings of a global ring study evaluating the analytical comparability of concordance of the results of 3 CLDN18 antibodies (Ventana, LSBio, and Novus) stained on 3 IHC-staining platforms (Ventana, Dako, and Leica). A tissue microarray (TMA), comprising 15 gastric cancer cases, was stained by 27 laboratories across 11 countries. Each laboratory stained the TMAs using at least 2 of the 3 evaluated CLDN18 antibodies. Stained TMAs were assessed and scored using an agreed IHC-scoring algorithm, and the results were collated for statistical analysis. The data confirmed a high level of concordance for the VENTANA CLDN18 (43-14A; Ventana platform only) and LSBio antibodies on both the Dako and Leica platforms, with accuracy, precision, sensitivity, and specificity rates all reaching a minimum acceptable ≥85% threshold and good-to-excellent levels of concordance as measured by Cohen's kappa coefficient. The Novus antibody showed the highest level of variability against the reference central laboratory results for the same antibody/platform combinations. It also failed to meet the threshold for accuracy and sensitivity when used on either the Dako or Leica platform. These results demonstrated the reliability of IHC testing for CLDN18 expression in gastric tumor samples when using commercially available platforms with an appropriate methodology and primary antibody selection.


Assuntos
Compostos Organofosforados , Polímeros , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/metabolismo , Reprodutibilidade dos Testes , Junção Esofagogástrica/patologia , Claudinas
2.
Proc Natl Acad Sci U S A ; 118(17)2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33883278

RESUMO

Cancer cells can survive chemotherapy-induced stress, but how they recover from it is not known. Using a temporal multiomics approach, we delineate the global mechanisms of proteotoxic stress resolution in multiple myeloma cells recovering from proteasome inhibition. Our observations define layered and protracted programs for stress resolution that encompass extensive changes across the transcriptome, proteome, and metabolome. Cellular recovery from proteasome inhibition involved protracted and dynamic changes of glucose and lipid metabolism and suppression of mitochondrial function. We demonstrate that recovering cells are more vulnerable to specific insults than acutely stressed cells and identify the general control nonderepressable 2 (GCN2)-driven cellular response to amino acid scarcity as a key recovery-associated vulnerability. Using a transcriptome analysis pipeline, we further show that GCN2 is also a stress-independent bona fide target in transcriptional signature-defined subsets of solid cancers that share molecular characteristics. Thus, identifying cellular trade-offs tied to the resolution of chemotherapy-induced stress in tumor cells may reveal new therapeutic targets and routes for cancer therapy optimization.


Assuntos
Neoplasias/tratamento farmacológico , Estresse Fisiológico/efeitos dos fármacos , Antineoplásicos/farmacologia , Autofagia/fisiologia , Linhagem Celular Tumoral , Humanos , Metaboloma/genética , Mitocôndrias/metabolismo , Mieloma Múltiplo/metabolismo , Neoplasias/metabolismo , Neoplasias/fisiopatologia , Inibidores de Proteassoma/farmacologia , Proteólise , Proteoma/genética , Análise de Sistemas , Transcriptoma/genética
3.
Glia ; 71(8): 1870-1889, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37029764

RESUMO

Increasing evidence indicates that cellular identity can be reduced to the distinct gene regulatory networks controlled by transcription factors (TFs). However, redundancy exists in these states as different combinations of TFs can induce broadly similar cell types. We previously demonstrated that by overcoming gene silencing, it is possible to deterministically reprogram human pluripotent stem cells directly into cell types of various lineages. In the present study we leverage the consistency and precision of our approach to explore four different TF combinations encoding astrocyte identity, based on previously published reports. Analysis of the resulting induced astrocytes (iAs) demonstrated that all four cassettes generate cells with the typical morphology of in vitro astrocytes, which expressed astrocyte-specific markers. The transcriptional profiles of all four iAs clustered tightly together and displayed similarities with mature human astrocytes, although maturity levels differed between cells. Importantly, we found that the TF cassettes induced iAs with distinct differences with regards to their cytokine response and calcium signaling. In vivo transplantation of selected iAs into immunocompromised rat brains demonstrated long term stability and integration. In conclusion, all four TF combinations were able to induce stable astrocyte-like cells that were morphologically similar but showed subtle differences with respect to their transcriptome. These subtle differences translated into distinct differences with regards to cell function, that could be related to maturation state and/or regional identity of the resulting cells. This insight opens an opportunity to precision-engineer cells to meet functional requirements, for example, in the context of therapeutic cell transplantation.


Assuntos
Células-Tronco Neurais , Fatores de Transcrição , Ratos , Animais , Humanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Astrócitos/metabolismo , Regulação da Expressão Gênica , Células-Tronco Neurais/metabolismo , Transcriptoma , Diferenciação Celular/fisiologia
4.
Clin Exp Rheumatol ; 40(12): 2363-2372, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36541240

RESUMO

OBJECTIVES: B cells play a central role in Sjögren's syndrome (SS) whereby autoreactive B-cells populate ectopic germinal centres (GC) in SS salivary glands (SG) and undergo somatic hypermutation (SHM) and class-switch recombination of the immunoglobulin genes. However, the capacity of specific B cell clones to seed ectopic GC in different SG and undergo clonal diversification is unclear. To unravel the dynamics of B cell recirculation among minor SG biopsies, we investigated the immunoglobulin heavy chain (IgH) gene usage and the pattern of SHM using a high-throughput sequencing approach. METHODS: We generated ~166,000 reads longer than 350bp and detected 1631 clonotypes across eight samples from four different SS patients, all characterised by the presence of functional ectopic GC as demonstrated by the expression of activation-induced cytidine deaminase. RESULTS: A large number of shared clonotypes were observed among paired mSG biopsies from each patient but not across different patients. Lineage tree analysis revealed significant clonal expansion within the mSG with the identification of shared dominant B cell clones suggestive of extensive recirculation across different SG. Several shared clonotypes with high proliferating capacity displayed IgH-VH gene usage common in autoreactive B cells, including VH1-69, which is typical of rheumatoid factor+ B cells representing potential lymphoma precursors. CONCLUSIONS: The complex dynamic recirculation of B cells that we observed within ectopic GC responses linked with their ability to independently proliferate, undergo ongoing SHM and Ig class-switching within individual glands may explain the difficulty in achieving consistent eradication of ectopic GCs following B cell depleting agents reported in different studies.


Assuntos
Síndrome de Sjogren , Humanos , Linfócitos B/patologia , Sequenciamento de Nucleotídeos em Larga Escala , Glândulas Salivares Menores/patologia , Síndrome de Sjogren/patologia
5.
Microvasc Res ; 136: 104167, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33838207

RESUMO

PURPOSE: Congenital heart disease (CHD) is the most common live birth defect and a proportion of these patients have chronic hypoxia. Chronic hypoxia leads to secondary erythrocytosis resulting in microvascular dysfunction and increased thrombosis risk. The conjunctival microcirculation is easily accessible for imaging and quantitative assessment. It has not previously been studied in adult CHD patients with cyanosis (CCHD). METHODS: We assessed the conjunctival microcirculation and compared CCHD patients and matched healthy controls to determine if there were differences in measured microcirculatory parameters. We acquired images using an iPhone 6s and slit-lamp biomicroscope. Parameters measured included diameter, axial velocity, wall shear rate and blood volume flow. The axial velocity was estimated by applying the 1D + T continuous wavelet transform (CWT). Results are for all vessels as they were not sub-classified into arterioles or venules. RESULTS: 11 CCHD patients and 14 healthy controls were recruited to the study. CCHD patients were markedly more hypoxic compared to the healthy controls (84% vs 98%, p = 0.001). A total of 736 vessels (292 vs 444) were suitable for analysis. Mean microvessel diameter (D) did not significantly differ between the CCHD patients and controls (20.4 ± 2.7 µm vs 20.2 ± 2.6 µm, p = 0.86). Axial velocity (Va) was lower in the CCHD patients (0.47 ± 0.06 mm/s vs 0.53 ± 0.05 mm/s, p = 0.03). Blood volume flow (Q) was lower for CCHD patients (121 ± 30pl/s vs 145 ± 50pl/s, p = 0.65) with the greatest differences observed in vessels >22 µm diameter (216 ± 121pl/s vs 258 ± 154pl/s, p = 0.001). Wall shear rate (WSR) was significantly lower for the CCHD group (153 ± 27 s-1 vs 174 ± 22 s-1, p = 0.04). CONCLUSIONS: This iPhone and slit-lamp combination assessment of conjunctival vessels found lower axial velocity, wall shear rate and in the largest vessel group, lower blood volume flow in chronically hypoxic patients with congenital heart disease. With further study this assessment method may have utility in the evaluation of patients with chronic hypoxia.


Assuntos
Túnica Conjuntiva/irrigação sanguínea , Cianose/diagnóstico , Cardiopatias Congênitas/diagnóstico , Microcirculação , Microscopia com Lâmpada de Fenda , Adulto , Velocidade do Fluxo Sanguíneo , Estudos de Casos e Controles , Cianose/etiologia , Cianose/fisiopatologia , Feminino , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fluxo Sanguíneo Regional , Lâmpada de Fenda , Microscopia com Lâmpada de Fenda/instrumentação , Smartphone , Estresse Mecânico , Adulto Jovem
6.
Mol Ther ; 28(8): 1846-1857, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32416058

RESUMO

CRISPR-Cas9 provides a tool to treat autosomal dominant disease by non-homologous end joining (NHEJ) gene disruption of the mutant allele. In order to discriminate between wild-type and mutant alleles, Streptococcus pyogenes Cas9 (SpCas9) must be able to detect a single nucleotide change. Allele-specific editing can be achieved by using either a guide-specific approach, in which the missense mutation is found within the guide sequence, or a protospacer-adjacent motif (PAM)-specific approach, in which the missense mutation generates a novel PAM. While both approaches have been shown to offer allele specificity in certain contexts, in cases where numerous missense mutations are associated with a particular disease, such as TGFBI (transforming growth factor ß-induced) corneal dystrophies, it is neither possible nor realistic to target each mutation individually. In this study, we demonstrate allele-specific CRISPR gene editing independent of the disease-causing mutation that is capable of achieving complete allele discrimination, and we propose it as a targeting approach for autosomal dominant disease. Our approach utilizes natural variants in the target region that contain a PAM on one allele that lies in cis with the causative mutation, removing the constraints of a mutation-dependent approach. Our innovative patient-specific guide design approach takes into account the patient's individual genetic make-up, allowing on- and off-target activity to be assessed in a personalized manner.


Assuntos
Alelos , Sistemas CRISPR-Cas , Edição de Genes , Genes Dominantes , Doenças Genéticas Inatas/genética , Doenças Genéticas Inatas/terapia , Terapia Genética , Mutação , Sequência de Aminoácidos , Substituição de Aminoácidos , Linhagem Celular , Genômica/métodos , Haplótipos , Humanos , Polimorfismo de Nucleotídeo Único , Medicina de Precisão , RNA Guia de Cinetoplastídeos , Fator de Crescimento Transformador beta1/genética
7.
Int J Mol Sci ; 22(7)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33916195

RESUMO

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an ultra-rare disease for which there are currently no validated outcome measures for assessing therapeutic intervention efficacy. The aim of this study was to identify a plasma and/or serum microRNA (miRNA) biomarker panel for MNGIE. Sixty-five patients and 65 age and sex matched healthy controls were recruited and assigned to one of four study phases: (i) discovery for sample size determination; (ii) candidate screening; (iii) candidate validation; and (iv) verifying the performance of the validated miRNA panel in four patients treated with erythrocyte-encapsulated thymidine phosphorylase (EE-TP), an enzyme replacement under development for MNGIE. Quantitative PCR (qPCR) was used to profile miRNAs in serum and/or plasma samples collected for the discovery, validation and performance phases, and next generation sequencing (NGS) analysis was applied to serum samples assigned to the candidate screening phase. Forty-one differentially expressed candidate miRNAs were identified in the sera of patients (p < 0.05, log2 fold change > 1). The validation cohort revealed that of those, 27 miRNAs were upregulated in plasma and three miRNAs were upregulated in sera (p < 0.05). Through binary logistic regression analyses, five plasma miRNAs (miR-192-5p, miR-193a-5p, miR-194-5p, miR-215-5p and miR-34a-5p) and three serum miRNAs (miR-192-5p, miR-194-5p and miR-34a-5p) were shown to robustly distinguish MNGIE from healthy controls. Reduced longitudinal miRNA expression of miR-34a-5p was observed in all four patients treated with EE-TP and coincided with biochemical and clinical improvements. We recommend the inclusion of the plasma exploratory miRNA biomarker panel in future clinical trials of investigational therapies for MNGIE; it may have prognostic value for assessing clinical status.


Assuntos
Pseudo-Obstrução Intestinal/sangue , MicroRNAs/sangue , Distrofia Muscular Oculofaríngea/sangue , Oftalmoplegia/congênito , Biomarcadores/sangue , Estudos de Casos e Controles , Perfilação da Expressão Gênica , Humanos , Oftalmoplegia/sangue
8.
Eur Respir J ; 54(4)2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31439681

RESUMO

Evidence suggests vitamin D has preventive potential in asthma; however, not all children benefit from this intervention. This study aimed to investigate whether variation in the functional 17q21 single nucleotide polymorphism rs12936231 affects the preventive potential of vitamin D against asthma.A combined secondary analysis of two randomised controlled trials of prenatal vitamin D supplementation for the prevention of asthma in offspring (Vitamin D Antenatal Asthma Reduction Trial (VDAART) and Copenhagen Prospective Studies on Asthma in Childhood 2010 (COPSAC2010)) was performed, stratifying by genotype and integrating metabolite data to explore underlying mechanisms.The protective effect of vitamin D on asthma/wheeze was evident among children with the low-risk rs12936231 GG genotype (hazard ratio (HR) 0.49, 95% CI 0.26-0.94, p=0.032) but not the high-risk CC genotype (HR 1.08, 95% CI 0.69-1.69, p=0.751). In VDAART, in the GG genotype vitamin D supplementation was associated with increased plasma levels of sphingolipids, including sphingosine-1-phosphate (ß 0.022, 95% CI 0.001-0.044, p=0.038), but this was not evident with the CC genotype, known to be associated with increased expression of ORMDL3 in bronchial epithelial cells. Sphingolipid levels were associated with decreased risk of asthma/wheeze, and there was evidence of interactions between sphingolipid levels, vitamin D and genotype (p-interactionvitaminD*genotype*sphingosine-1-phosphate=0.035). In a cellular model, there was a significant difference in the induction of sphingosine-1-phosphate by vitamin D between a control human bronchial epithelial cell line and a cell line overexpressing ORMDL3 (p=0.002).Results suggest prenatal vitamin D supplementation may reduce the risk of early childhood asthma/wheeze via alterations of sphingolipid metabolism dependent on the 17q21 genotype.


Assuntos
Asma/prevenção & controle , Colecalciferol/uso terapêutico , Esfingolipídeos/metabolismo , Vitaminas/uso terapêutico , Alelos , Asma/genética , Asma/metabolismo , Linhagem Celular , Pré-Escolar , Cromossomos Humanos Par 17/genética , Etanolaminas/metabolismo , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Lactente , Recém-Nascido , Lisofosfolipídeos/metabolismo , Masculino , Proteínas de Membrana/metabolismo , Polimorfismo de Nucleotídeo Único , Gravidez , Cuidado Pré-Natal , Modelos de Riscos Proporcionais , Ensaios Clínicos Controlados Aleatórios como Assunto , Sons Respiratórios/genética , Esfingosina/análogos & derivados , Esfingosina/metabolismo , Resultado do Tratamento
9.
Microvasc Res ; 126: 103907, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31330150

RESUMO

PURPOSE: The conjunctival microcirculation is a readily-accessible vascular bed for quantitative haemodynamic assessment and has been studied previously using a digital charge-coupled device (CCD). Smartphone video imaging of the conjunctiva, and haemodynamic parameter quantification, represents a novel approach. We report the feasibility of smartphone video acquisition and subsequent haemodynamic measure quantification via semi-automated means. METHODS: Using an Apple iPhone 6 s and a Topcon SL-D4 slit-lamp biomicroscope, we obtained videos of the conjunctival microcirculation in 4 fields of view per patient, for 17 low cardiovascular risk patients. After image registration and processing, we quantified the diameter, mean axial velocity, mean blood volume flow, and wall shear rate for each vessel studied. Vessels were grouped into quartiles based on their diameter i.e. group 1 (<11 µm), 2 (11-16 µm), 3 (16-22 µm) and 4 (>22 µm). RESULTS: From the 17 healthy controls (mean QRISK3 6.6%), we obtained quantifiable haemodynamics from 626 vessel segments. The mean diameter of microvessels, across all sites, was 21.1µm (range 5.8-58 µm). Mean axial velocity was 0.50mm/s (range 0.11-1mm/s) and there was a modestly positive correlation (r 0.322) seen with increasing diameter, best appreciated when comparing group 4 to the remaining groups (p < .0001). Blood volume flow (mean 145.61pl/s, range 7.05-1178.81pl/s) was strongly correlated with increasing diameter (r 0.943, p < .0001) and wall shear rate (mean 157.31 s-1, range 37.37-841.66 s-1) negatively correlated with increasing diameter (r - 0.703, p < .0001). CONCLUSIONS: We, for the first time, report the successful assessment and quantification of the conjunctival microcirculatory haemodynamics using a smartphone-based system.


Assuntos
Doenças Cardiovasculares/diagnóstico , Túnica Conjuntiva/irrigação sanguínea , Técnicas de Diagnóstico Oftalmológico/instrumentação , Hemodinâmica , Microcirculação , Lâmpada de Fenda , Smartphone , Adulto , Velocidade do Fluxo Sanguíneo , Doenças Cardiovasculares/fisiopatologia , Estudos de Casos e Controles , Estudos de Viabilidade , Feminino , Hemorreologia , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Aplicativos Móveis , Modelos Cardiovasculares , Valor Preditivo dos Testes , Fluxo Sanguíneo Regional
10.
Blood ; 127(23): 2924-33, 2016 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-27060170

RESUMO

The development of neutralizing antibodies (inhibitors) against coagulation factor VIII (FVIII) is the most problematic and costly complication of FVIII replacement therapy that affects up to 30% of previously untreated patients with severe hemophilia A. The development of inhibitors is a multifactorial complication involving environmental and genetic factors. Among the latter, F8 gene mutations, ethnicity, family history of inhibitors, and polymorphisms affecting genes involved in the immune response have been previously investigated. To identify novel genetic elements underling the risk of inhibitor development in patients with severe hemophilia A, we applied whole-exome sequencing (WES) and data analysis in a selected group of 26 Italian patients with (n = 17) and without (n = 9) inhibitors. WES revealed several rare, damaging variants in immunoregulatory genes as novel candidate mutations. A case-control association analysis using Cochran-Armitage and Fisher's exact statistical tests identified 1364 statistically significant variants. Hierarchical clustering of these genetic variants showed 2 distinct patterns of homozygous variants with a protective or harmful role in inhibitor development. When looking solely at coding variants, a total of 28 nonsynonymous variants were identified and replicated in 53 inhibitor-positive and 174 inhibitor-negative Italian severe hemophilia A patients using a TaqMan genotyping assay. The genotyping results revealed 10 variants showing estimated odds ratios in the same direction as in the discovery phase and confirmed the association of the rs3754689 missense variant (OR 0.58; 95% CI 0.36-0.94; P = .028) in a highly conserved haplotype region surrounding the LCT locus on chromosome 2q21 with inhibitor development.


Assuntos
Anticorpos Neutralizantes/biossíntese , Inibidores dos Fatores de Coagulação Sanguínea/biossíntese , Predisposição Genética para Doença , Hemofilia A/genética , Mutação , Estudos de Casos e Controles , Análise Mutacional de DNA/métodos , Estudo de Associação Genômica Ampla , Hemofilia A/imunologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Índice de Gravidade de Doença
11.
Metabolomics ; 13(7)2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-30473646

RESUMO

Introduction: Preeclampsia represents a major public health burden worldwide, but predictive and diagnostic biomarkers are lacking. Metabolomics is emerging as a valuable approach to generating novel biomarkers whilst increasing the mechanistic understanding of this complex condition. Objectives: To summarize the published literature on the use of metabolomics as a tool to study preeclampsia. Methods: PubMed and Web of Science were searched for articles that performed metabolomic profiling of human biosamples using either Mass-spectrometry or Nuclear Magnetic Resonance based approaches and which included preeclampsia as a primary endpoint. Results: Twenty-eight studies investigating the metabolome of preeclampsia in a variety of biospecimens were identified. Individual metabolite and metabolite profiles were reported to have discriminatory ability to distinguish preeclamptic from normal pregnancies, both prior to and post diagnosis. Lipids and carnitines were among the most commonly reported metabolites. Further work and validation studies are required to demonstrate the utility of such metabolites as preeclampsia biomarkers. Conclusion: Metabolomic-based biomarkers of preeclampsia have yet to be integrated into routine clinical practice. However, metabolomic profiling is becoming increasingly popular in the study of preeclampsia and is likely to be a valuable tool to better understand the pathophysiology of this disorder and to better classify its subtypes, particularly when integrated with other omic data.

12.
Genome Res ; 22(2): 220-31, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21990379

RESUMO

Biomarkers in breast cancer to monitor minimal residual disease have remained elusive. We hypothesized that genomic analysis of circulating free DNA (cfDNA) isolated from plasma may form the basis for a means of detecting and monitoring breast cancer. We profiled 251 genomes using Affymetrix SNP 6.0 arrays to determine copy number variations (CNVs) and loss of heterozygosity (LOH), comparing 138 cfDNA samples with matched primary tumor and normal leukocyte DNA in 65 breast cancer patients and eight healthy female controls. Concordance of SNP genotype calls in paired cfDNA and leukocyte DNA samples distinguished between breast cancer patients and healthy female controls (P < 0.0001) and between preoperative patients and patients on follow-up who had surgery and treatment (P = 0.0016). Principal component analyses of cfDNA SNP/copy number results also separated presurgical breast cancer patients from the healthy controls, suggesting specific CNVs in cfDNA have clinical significance. We identified focal high-level DNA amplification in paired tumor and cfDNA clustered in a number of chromosome arms, some of which harbor genes with oncogenic potential, including USP17L2 (DUB3), BRF1, MTA1, and JAG2. Remarkably, in 50 patients on follow-up, specific CNVs were detected in cfDNA, mirroring the primary tumor, up to 12 yr after diagnosis despite no other evidence of disease. These data demonstrate the potential of SNP/CNV analysis of cfDNA to distinguish between patients with breast cancer and healthy controls during routine follow-up. The genomic profiles of cfDNA infer dormancy/minimal residual disease in the majority of patients on follow-up.


Assuntos
Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , DNA/sangue , Neoplasias da Mama/diagnóstico , Aberrações Cromossômicas , Variações do Número de Cópias de DNA , Feminino , Seguimentos , Humanos , Perda de Heterozigosidade , Polimorfismo de Nucleotídeo Único
13.
Cancer Metastasis Rev ; 32(1-2): 289-302, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23108389

RESUMO

Breast cancer treatment is improving due to the introduction of new drugs, guided by molecular testing of the primary tumour for mutations/oncogenic drivers (e.g. HER2 gene amplification). However, tumour tissue is not always available for molecular analysis, intra-tumoural heterogeneity is common and the "cancer genome" is known to evolve with time, particularly following treatment as resistance develops. After resection, those patients with only residual micrometastases are likely to be cured but those with radiologically detectable overt disease are not. Thus, the discovery of blood test(s) that could (1) alert clinicians to early primary or recurrent disease and (2) monitor response to treatment could impact significantly on mortality. Towards this, we and others have focused on molecular profiling of circulating nucleic acids isolated from plasma, both cell-free DNA (cfDNA) and microRNAs, and the relationship of these to circulating tumour cells (CTCs). This review considers the utility of each as circulating biomarkers in breast cancer with particular emphasis on the bioinformatic tools available to support molecular profiling.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , DNA/sangue , Feminino , Humanos , MicroRNAs/sangue , Metástase Neoplásica , Células Neoplásicas Circulantes , Análise de Componente Principal
14.
Vaccine ; 40(18): 2535-2539, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35346536

RESUMO

BACKGROUND: This study evaluates spike protein IgG antibody response following Oxford-AstraZeneca COVID-19 vaccination using the AbC-19™ lateral flow device. METHODS: Plasma samples were collected from n = 111 individuals from Northern Ireland. The majority were >50 years old and/or clinically vulnerable. Samples were taken at five timepoints from pre-vaccination until 6-months post-first dose. RESULTS: 20.3% of participants had detectable IgG responses pre-vaccination, indicating prior COVID-19. Antibodies were detected in 86.9% of participants three weeks after the first vaccine dose, falling to 74.7% immediately prior to the second dose, and rising to 99% three weeks post-second vaccine. At 6-months post-first dose, this decreased to 90.5%. At all timepoints, previously infected participants had significantly higher antibody levels than those not previously infected. CONCLUSION: This study demonstrates that strong anti-spike protein antibody responses are evoked in almost all individuals that receive two doses of Oxford-AstraZeneca vaccine, and which largely persist beyond six months after first vaccination.


Assuntos
Formação de Anticorpos , COVID-19 , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Imunoglobulina G , Pessoa de Meia-Idade , Irlanda do Norte , SARS-CoV-2 , Vacinação
15.
Comput Biol Med ; 135: 104584, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34171638

RESUMO

Papillary Thyroid Carcinoma (PTC) accounts for approximately 85% of patients with thyroid cancer. Despite its indolent nature, progression to higher stages is expected in a subgroup of patients. Hence, genomic characterization of the early stages of PTC may help to identify this subgroup, leading to better clinical management. Here, we conducted a comprehensive mutational and somatic copy number alteration (SCNA) investigation on 277 stage one PTC from TCGA. SCNA analysis revealed amplification and deletion of several cancer related genes. We found amplification of 60 oncogenes (Oncs), from which 15 were recurrently observed. Deletion of 58 tumor suppressors (TSs) was also detected. MAPK, PI3K-Akt, Rap1 and Ras were the signaling pathways with large numbers of amplified Oncs. On the other hand, deleted TSs belonged mostly to cell cycle, PI3K-Akt, mTOR and cellular senescence pathways. This suggests that despite heterogeneity in SCNA events, the final results would be the activation/deactivation of a few cancer signaling pathways. Of note, despite large amounts of heterogeneity in stage one PTC, recurrent broad deletion on Chr22 was detected in 21 individuals, leading to deletion of several tumor suppressors. In parallel, the oncogenic/pathogenic mutations in the RTK-RAS and PI3k-Akt pathways were detected. However, no pathogenic mutation was identified in known tumor suppressor genes. In order to identify a potential subgroup of BRAF (V600E) positive patients, who might progress to higher stages, low frequency mutations accompanying BRAF (V600E) were also identified. In conclusion, our findings imply that SCNA have a substantial contribution to early stages of PTC. Experimental validation of the observed genomic alterations could help to stratify patients at the time of diagnosis, and to move toward precision medicine in PTC.


Assuntos
Carcinoma Papilar , Neoplasias da Glândula Tireoide , Variações do Número de Cópias de DNA/genética , Humanos , Mutação , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas B-raf/genética , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética
16.
Gene ; 768: 145301, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33181261

RESUMO

Despite the economic importance of P utilization efficiency, information on genetic factors underlying this trait remains elusive. To address that, we performed a genome-wide association study in a spring wheat diversity panel ranging from landraces to elite varieties. We evaluated the phenotype variation for P utilization efficiency in controlled conditions and genotype variation using wheat 90 K SNP array. Phenotype variables were transformed into a smaller set of uncorrelated principal components that captured the most important variation data. We identified two significant loci associated with both P utilization efficiency and the 1st principal component on chromosomes 3A and 4A: qPE1-3A and qPE2-4A. Annotation of genes at these loci revealed 53 wheat genes, among which 6 were identified in significantly enriched pathways. The expression pattern of these 6 genes indicated that TraesCS4A02G481800, involved in pyruvate metabolism and TCA cycle, had a significantly higher expression in the P efficient variety under limited P conditions. Further characterization of these loci and candidate genes can help stimulate P utilization efficiency in wheat.


Assuntos
Fósforo/metabolismo , Triticum/genética , Triticum/metabolismo , Alelos , Mapeamento Cromossômico/métodos , Cromossomos de Plantas/genética , Genoma de Planta/genética , Estudo de Associação Genômica Ampla/métodos , Genótipo , Desequilíbrio de Ligação/genética , Fenótipo , Melhoramento Vegetal/métodos , Polimorfismo de Nucleotídeo Único/genética , Análise de Componente Principal/métodos , Locos de Características Quantitativas/genética
17.
Sci Rep ; 11(1): 13654, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34211028

RESUMO

Prediction models for population-based screening need, for global usage, to be resource-driven, involving predictors that are affordably resourced. Here, we report the development and validation of three resource-driven risk models to identify people with type 2 diabetes (T2DM) at risk of stage 3 CKD defined by a decline in estimated glomerular filtration rate (eGFR) to below 60 mL/min/1.73m2. The observational study cohort used for model development consisted of data from a primary care dataset of 20,510 multi-ethnic individuals with T2DM from London, UK (2007-2018). Discrimination and calibration of the resulting prediction models developed using cox regression were assessed using the c-statistic and calibration slope, respectively. Models were internally validated using tenfold cross-validation and externally validated on 13,346 primary care individuals from Wales, UK. The simplest model was simplified into a risk score to enable implementation in community-based medicine. The derived full model included demographic, laboratory parameters, medication-use, cardiovascular disease history (CVD) and sight threatening retinopathy status (STDR). Two less resource-intense models were developed by excluding CVD and STDR in the second model and HbA1c and HDL in the third model. All three 5-year risk models had good internal discrimination and calibration (optimism adjusted C-statistics were each 0.85 and calibration slopes 0.999-1.002). In Wales, models achieved excellent discrimination(c-statistics ranged 0.82-0.83). Calibration slopes at 5-years suggested models over-predicted risks, however were successfully updated to accommodate reduced incidence of stage 3 CKD in Wales, which improved their alignment with the observed rates in Wales (E/O ratios near to 1). The risk score demonstrated similar model performance compared to direct evaluation of the cox model. These resource-driven risk prediction models may enable universal screening for Stage 3 CKD to enable targeted early optimisation of risk factors for CKD.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Insuficiência Renal Crônica/etiologia , Adulto , Idoso , Feminino , Taxa de Filtração Glomerular , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Insuficiência Renal Crônica/diagnóstico , Fatores de Risco
18.
Sci Rep ; 11(1): 7660, 2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-33828174

RESUMO

Microcirculatory dysfunction occurs early in cardiovascular disease (CVD) development. Acute myocardial infarction (MI) is a late consequence of CVD. The conjunctival microcirculation is readily-accessible for quantitative assessment and has not previously been studied in MI patients. We compared the conjunctival microcirculation of acute MI patients and age/sex-matched healthy controls to determine if there were differences in microcirculatory parameters. We acquired images using an iPhone 6s and slit-lamp biomicroscope. Parameters measured included diameter, axial velocity, wall shear rate and blood volume flow. Results are for all vessels as they were not sub-classified into arterioles or venules. The conjunctival microcirculation was assessed in 56 controls and 59 inpatients with a presenting diagnosis of MI. Mean vessel diameter for the controls was 21.41 ± 7.57 µm compared to 22.32 ± 7.66 µm for the MI patients (p < 0.001). Axial velocity for the controls was 0.53 ± 0.15 mm/s compared to 0.49 ± 0.17 mm/s for the MI patients (p < 0.001). Wall shear rate was higher for controls than MI patients (162 ± 93 s-1 vs 145 ± 88 s-1, p < 0.001). Blood volume flow did not differ significantly for the controls and MI patients (153 ± 124 pl/s vs 154 ± 125 pl/s, p = 0.84). This pilot iPhone and slit-lamp assessment of the conjunctival microcirculation found lower axial velocity and wall shear rate in patients with acute MI. Further study is required to correlate these findings further and assess long-term outcomes in this patient group with a severe CVD phenotype.


Assuntos
Túnica Conjuntiva/irrigação sanguínea , Microcirculação , Infarto do Miocárdio sem Supradesnível do Segmento ST/fisiopatologia , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
19.
Sci Rep ; 11(1): 5682, 2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-33707504

RESUMO

WNT ligands can activate several signalling cascades of pivotal importance during development and regenerative processes. Their de-regulation has been associated with the onset of different diseases. Here we investigated the role of the WNT/Calcium Calmodulin Kinase II (CaMKII) pathway in osteoarthritis. We identified Heme Oxygenase I (HMOX1) and Sox-9 as specific markers of the WNT/CaMKII signalling in articular chondrocytes through a microarray analysis. We showed that the expression of the activated form of CaMKII, phospho-CaMKII, was increased in human and murine osteoarthritis and the expression of HMOX1 was accordingly reduced, demonstrating the activation of the pathway during disease progression. To elucidate its function, we administered the CaMKII inhibitor KN93 to mice in which osteoarthritis was induced by resection of the anterior horn of the medial meniscus and of the medial collateral ligament in the knee joint. Pharmacological blockade of CaMKII exacerbated cartilage damage and bone remodelling. Finally, we showed that CaMKII inhibition in articular chondrocytes upregulated the expression of matrix remodelling enzymes alone and in combination with Interleukin 1. These results suggest an important homeostatic role of the WNT/CaMKII signalling in osteoarthritis which could be exploited in the future for therapeutic purposes.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Cartilagem Articular/enzimologia , Cartilagem Articular/patologia , Homeostase , Osteoartrite/enzimologia , Osteoartrite/patologia , Idoso , Animais , Remodelação Óssea , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Bovinos , Condrócitos/metabolismo , Condrócitos/patologia , Modelos Animais de Doenças , Feminino , Regulação Enzimológica da Expressão Gênica , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Humanos , Interleucina-1beta/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Modelos Biológicos , Osteoartrite/genética , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Transcriptoma/genética , Regulação para Cima , Proteína Wnt3/metabolismo
20.
Elife ; 102021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33929322

RESUMO

High-dimensional cytometry is an innovative tool for immune monitoring in health and disease, and it has provided novel insight into the underlying biology as well as biomarkers for a variety of diseases. However, the analysis of large multiparametric datasets usually requires specialist computational knowledge. Here, we describe ImmunoCluster (https://github.com/kordastilab/ImmunoCluster), an R package for immune profiling cellular heterogeneity in high-dimensional liquid and imaging mass cytometry, and flow cytometry data, designed to facilitate computational analysis by a nonspecialist. The analysis framework implemented within ImmunoCluster is readily scalable to millions of cells and provides a variety of visualization and analytical approaches, as well as a rich array of plotting tools that can be tailored to users' needs. The protocol consists of three core computational stages: (1) data import and quality control; (2) dimensionality reduction and unsupervised clustering; and (3) annotation and differential testing, all contained within an R-based open-source framework.


Assuntos
Alergia e Imunologia , Biologia Computacional/métodos , Citometria de Fluxo/métodos , Algoritmos , Linfócitos B/citologia , Linfócitos B/imunologia , Análise de Dados , Humanos
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