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1.
Mikrochim Acta ; 191(7): 369, 2024 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834823

RESUMO

A trendsetting direct competitive-based biosensing tool has been developed and implemented for the determination of the polyunsaturated fatty acid arachidonic acid (ARA), a highly significant biological regulator with decisive roles in viral infections. The designed methodology involves a competitive reaction between the target endogenous ARA and a biotin-ARA competitor for the recognition sites of anti-ARA antibodies covalently attached to the surface of carboxylic acid-coated magnetic microbeads (HOOC-MµBs), followed by the enzymatic label of the biotin-ARA residues with streptavidin-horseradish peroxidase (Strep-HRP) conjugate. The resulting bioconjugates were magnetically trapped onto the sensing surface of disposable screen-printed carbon transducers (SPCEs) to monitor the extent of the biorecognition reaction through amperometry. The operational functioning of the exhaustively optimized and characterized immunosensing bioplatform was highly convenient for the quantitative determination of ARA in serum samples from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2-) and respiratory syncytial virus (RSV)-infected individuals in a rapid, affordable, trustful, and sensitive manner.


Assuntos
Ácido Araquidônico , Técnicas Biossensoriais , COVID-19 , SARS-CoV-2 , Humanos , Ácido Araquidônico/sangue , COVID-19/sangue , COVID-19/diagnóstico , COVID-19/imunologia , Técnicas Biossensoriais/métodos , SARS-CoV-2/imunologia , Peroxidase do Rábano Silvestre/química , Vírus Sinciciais Respiratórios/imunologia , Imunoensaio/métodos , Estreptavidina/química , Biotina/química , Limite de Detecção
2.
Bioinformatics ; 38(8): 2374-2376, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35179562

RESUMO

MOTIVATION: Genomic alterations can modulate the tumor immunophenotype depending on their nature and tissue of origin. Although this immune-genomic interaction may shape disease progression and response to immunotherapy, the factors governing such dynamics and the influence of each tissue-specific context remain poorly understood. RESULTS: Here, we have developed the PanCancer ImmunoGenomics (PCIG) tool, a web-based resource that provides researchers with the opportunity to mine immunome-genome relationships across several cancer types using data from the Pan-Cancer Analysis of Whole-Genomes (PCAWG) study, which comprises >2,600 samples spanning across 20 different cancer primary sites. PCIG yields an integrative analysis of the crosstalk between somatic genomic alterations and different immune features, thus helping to understand immune response-related processes. AVAILABILITY AND IMPLEMENTATION: PCIG is freely available at https://pcig.vhio.net and is supported by all major web browsers. PCIG was developed with Django, which is a Python-based free and open-source framework, and it uses SQL Server as a relational database management system. The code is freely available for download at GitHub https://github.com/AnnaPG/PCIG and in its online supplementary material. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Genômica , Neoplasias , Humanos , Software , Genoma , Neoplasias/genética , Internet
3.
J Pathol ; 257(1): 68-81, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35066875

RESUMO

Optimal selection of high-risk patients with stage II colon cancer is crucial to ensure clinical benefit of adjuvant chemotherapy. Here, we investigated the prognostic value of genomic intratumor heterogeneity and aneuploidy for disease recurrence. We combined targeted sequencing, SNP arrays, fluorescence in situ hybridization, and immunohistochemistry on a retrospective cohort of 84 untreated stage II colon cancer patients. We assessed the clonality of copy-number alterations (CNAs) and mutations, CD8+ lymphocyte infiltration, and their association with time to recurrence. Prognostic factors were included in machine learning analysis to evaluate their ability to predict individual relapse risk. Tumors from recurrent patients displayed a greater proportion of CNAs compared with non-recurrent (mean 31.3% versus 23%, respectively; p = 0.014). Furthermore, patients with elevated tumor CNA load exhibited a higher risk of recurrence compared with those with low levels [p = 0.038; hazard ratio (HR) 2.46], which was confirmed in an independent cohort (p = 0.004; HR 3.82). Candidate chromosome-specific aberrations frequently observed in recurrent cases included gain of the chromosome arm 13q (p = 0.02; HR 2.67) and loss of heterozygosity at 17q22-q24.3 (p = 0.05; HR 2.69). CNA load positively correlated with intratumor heterogeneity (R = 0.52; p < 0.0001). Consistently, incremental subclonal CNAs were associated with an elevated risk of relapse (p = 0.028; HR 2.20), which we did not observe for subclonal single-nucleotide variants and small insertions and deletions. The clinico-genomic model rated an area under the curve of 0.83, achieving a 10% incremental gain compared with clinicopathological markers (p = 0.047). In conclusion, tumor aneuploidy and copy-number intratumor heterogeneity were predictive of poor outcome and improved discriminative performance in early-stage colon cancer. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Neoplasias do Colo , Recidiva Local de Neoplasia , Aneuploidia , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Variações do Número de Cópias de DNA , Humanos , Hibridização in Situ Fluorescente , Recidiva Local de Neoplasia/genética , Prognóstico , Estudos Retrospectivos
4.
Curr Microbiol ; 80(11): 348, 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37733061

RESUMO

Early sepsis diagnosis is crucial for implementing adequate antibiotic therapy and for patient survival. This study investigated whether using multiplexed PCR for detecting microorganisms in critical septic patients affects initial antibiotic treatment and compared it to microbiological culture. It also explored scenarios where PCR is more effective in clinical practice. One hundred nineteen specimens (83 blood and 36 respiratory specimens) belonging to 93 patients were analyzed. Multiplexed PCR determinations were performed using the FA-BCID Panel (bioMérieux) for blood samples and the FA-Pneumo for respiratory samples. The mean turnaround times were 1.7 h for the FA-BCID and 1.5h for the FA-Pneumo. Conversely, they were 96.1 h for blood cultures and 72.3 h for respiratory cultures. FA-BCID showed a mean sensitivity of 97% and specificity of 100%. FA-Pneumo showed a sensitivity of 100% and specificity of 90%. However, the positive predictive value was only 39%. Discrepancies were common in polymicrobial samples. Based on the PCR results, initial empirical treatment should have been changed in 71% of patients with bloodstream infections and 61% with respiratory infections. We conclude that multiplexed PCR improves the response time in identifying germs with a high degree of coincidence for blood cultures and moderate for respiratory cultures. These results highlight the importance of PCR in choosing an appropriate antibiotic therapy.


Assuntos
Estado Terminal , Sepse , Humanos , Reação em Cadeia da Polimerase Multiplex , Hemocultura , Sepse/diagnóstico
5.
Mov Disord ; 37(10): 2086-2098, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35962561

RESUMO

BACKGROUND: Isolated rapid eye movement sleep behavior disorder (IRBD) is a well-established clinical risk factor for Lewy body diseases (LBDs), such as Parkinson's disease (PD) and dementia with Lewy bodies (DLB). OBJECTIVE: To elucidate whether serum microRNA (miRNA) deregulation in IRBD can antedate the diagnosis of LBD by performing a longitudinal study in different progression stages of IRBD before and after LBD diagnosis and assessing the predictive performance of differentially expressed miRNAs by machine learning-based modeling. METHODS: Using genome-wide miRNA analysis and real-time quantitative polymerase chain reaction validation, we assessed serum miRNA profiles from patients with IRBD stratified by dopamine transporter (DaT) single-photon emission computed tomography into DaT-negative IRBD (n = 17) and DaT-positive IRBD (n = 21), IRBD phenoconverted into LBD (n = 13), and controls (n = 20). Longitudinally, we followed up the IRBD cohort by studying three time point serum samples over 26 months. RESULTS: We found sustained cross-sectional and longitudinal deregulation of 12 miRNAs across the RBD continuum, including DaT-negative IRBD, DaT-positive IRBD, and LBD phenoconverted IRBD (let-7c-5p, miR-19b-3p, miR-140, miR-22-3p, miR-221-3p, miR-24-3p, miR-25-3p, miR-29c-3p, miR-361-5p, miR-425-5p, miR-4505, and miR-451a) (false discovery rate P < 0.05). Age- and sex-adjusted predictive modeling based on the 12 differentially expressed miRNA biosignatures discriminated IRBD and PD or DLB from controls with an area under the curve of 98% (95% confidence interval: 89-99%). CONCLUSIONS: Besides clinical diagnosis of IRBD or imaging markers such as DaT single-photon emission computed tomography, specific miRNA biosignatures alone hold promise as progression biomarkers for patients with IRBD for predicting PD and DLB clinical outcomes. Further miRNA studies in other PD at-risk populations, such as LRRK2 mutation asymptomatic carriers or hyposmic subjects, are warranted. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Doença por Corpos de Lewy , MicroRNAs , Doença de Parkinson , Transtorno do Comportamento do Sono REM , Biomarcadores , Estudos Transversais , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Humanos , Corpos de Lewy , Doença por Corpos de Lewy/diagnóstico , Doença por Corpos de Lewy/genética , Estudos Longitudinais , MicroRNAs/sangue , MicroRNAs/genética , Doença de Parkinson/diagnóstico , Doença de Parkinson/genética , Transtorno do Comportamento do Sono REM/diagnóstico , Transtorno do Comportamento do Sono REM/genética
6.
Anal Bioanal Chem ; 414(1): 399-412, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33635388

RESUMO

Metastasis is responsible for about 90% of cancer-associated deaths. In the context of solid tumors, the low oxygen concentration in the tumor microenvironment (hypoxia) is one of the key factors contributing to metastasis. Tumor cells adapt to these conditions by overexpressing certain proteins such as programmed death ligand 1 (PD-L1) and hypoxia-inducible factor 1 alpha (HIF-1α). However, the determination of these tumor hypoxia markers that can be used to follow-up tumor progression and improve the efficiency of therapies has been scarcely addressed using electrochemical biosensors. In this work, we report the first electrochemical bioplatform for the determination of PD-L1 as well as the first one allowing its simultaneous determination with HIF-1α. The target proteins were captured and enzymatically labeled on magnetic microbeads and amperometric detection was undertaken on the surface of screen-printed dual carbon electrodes using the hydrogen peroxide/peroxidase/hydroquinone system. Sandwich immunoassays were implemented for both the HIF-1α and PD-L1 sensors and the analytical characteristics were evaluated providing LOD values of 86 and 279 pg mL-1 for the amperometric determination of PD-L1 and HIF-1α standards, respectively. The developed electrochemical immunoplatforms are competitive versus the only electrochemical immunosensor reported for the determination of HIF-1α and the "gold standard" ELISA methodology for the single determination of both proteins in terms of assay time, compatibility with the simultaneous determination of both proteins making their use suitable for untrained users at the point of attention. The dual amperometric immunosensor was applied to the simultaneous determination of HIF-1α and PD-L1 in cancer cell lysates. The analyses lasted only 2 h and just 0.5 µg of the sample was required.


Assuntos
Biomarcadores Tumorais , Técnicas Biossensoriais , Biomarcadores Tumorais/análise , Técnicas Biossensoriais/métodos , Humanos , Hipóxia , Imunoensaio , Hipóxia Tumoral
7.
Int J Mol Sci ; 23(14)2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35887177

RESUMO

The surgically induced remission of liver disease represents a model to investigate the signalling processes that trigger the development of nonalcoholic steatohepatitis with the aim of identifying novel therapeutic targets. We recruited patients with severe obesity with or without nonalcoholic steatohepatitis and obtained liver and plasma samples before and after laparoscopic sleeve gastrectomy for immunoblotting, immunocytochemical, metabolomic, transcriptomic and epigenetic analyses. Functional studies were performed in HepG2 cells and primary hepatocytes. Surgery was associated with a decrease in the inflammatory response and revealed the role of mitogen-activated protein kinases. Nonalcoholic steatohepatitis was associated with an increased glutaminolysis-induced production of α-ketoglutarate and the hyperactivation of mammalian target of rapamycin complex 1. These changes were crucial for adenosine monophosphate-activated protein kinase/mammalian target of rapamycin-driven pathways that modulated hepatocyte survival by coordinating apoptosis and autophagy and affected methylation-related epigenomic remodelling enzymes. Hepatic transcriptome signatures and differentially methylated genomic regions distinguished patients with and without steatohepatitis. Our results suggest that the increased glutaminolysis-induced α-ketoglutarate production and the mammalian target of rapamycin complex 1 dysregulation play a crucial role in the inefficient adaptive responses leading to steatohepatitis in obesity.


Assuntos
Laparoscopia , Hepatopatia Gordurosa não Alcoólica , Obesidade Mórbida , Gastrectomia/métodos , Humanos , Ácidos Cetoglutáricos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/genética , Obesidade Mórbida/cirurgia , Serina-Treonina Quinases TOR
8.
Curr Issues Mol Biol ; 43(2): 650-664, 2021 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-34287292

RESUMO

Although antioxidants can act locally to react with an oxidant, oral administration of "antioxidants" is quite useless in treating oxidative stress in tissues. Furthermore, it does not make sense to consider a vitamin as an antioxidant, but vitamin B3 leads to the in vivo formation of compounds that are essential for reducing this stress. A rigorous treatment of the subject indicates that to deal with oxidative stress, the most direct approach is to enhance the innate antioxidant mechanisms. The question is whether this is possible through daily activities. Diets can contain the necessary components for these mechanisms or may induce the expression of the genes involved in them. Another possibility is that pro-oxidant molecules in food increase the sensitivity and power of the detoxification pathways. This option is based on well-known DNA repair mechanisms after exposure to radiation (even from the Sun), or strong evidence of induction of antioxidant capacity after exposure to powerful pro-oxidants such as H2O2. More experimental work is required to test whether some molecules in food can increase the expression of antioxidant enzymes and/or improve antioxidant mechanisms. Identifying effective molecules to achieve such antioxidant power is critical to the food and nutraceutical industries. The potential of diet-based interventions to combat oxidative stress must be viewed from a new perspective.


Assuntos
Antioxidantes/administração & dosagem , Suplementos Nutricionais , Exposição Ambiental , Avaliação do Impacto na Saúde , Estresse Oxidativo/efeitos dos fármacos , Antioxidantes/metabolismo , Dano ao DNA , Reparo do DNA , Exposição Ambiental/efeitos adversos , Humanos , Microbiota , Exposição Ocupacional , Oxirredução , Exposição à Radiação , Espécies Reativas de Oxigênio/administração & dosagem , Espécies Reativas de Oxigênio/metabolismo
9.
J Hepatol ; 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33961941

RESUMO

BACKGROUND & AIMS: A holistic insight on the relationship between obesity and metabolic dysfunction-associated fatty liver disease is an unmet clinical need. Omics investigations can be used to investigate the multifaceted role of altered mitochondrial pathways to promote nonalcoholic steatohepatitis, a major risk factor for liver disease-associated death. There are no specific treatments but remission via surgery might offer an opportunity to examine the signaling processes that govern the complex spectrum of chronic liver diseases observed in extreme obesity. We aim to assess the emerging relationship between metabolism, methylation and liver disease. METHODS: We tailed the flow of information, before and after steatohepatitis remission, from biochemical, histological, and multi-omics analyses in liver biopsies from patients with extreme obesity and successful bariatric surgery. Functional studies were performed in HepG2 cells and primary hepatocytes. RESULTS: The reversal of hepatic mitochondrial dysfunction and the control of oxidative stress and inflammatory responses revealed the regulatory role of mitogen-activated protein kinases. The reversible metabolic rearrangements leading to steatohepatitis increased the glutaminolysis-induced production of α-ketoglutarate and the hyperactivation of mammalian target of rapamycin complex 1. These changes were crucial for the adenosine monophosphate-activated protein kinase/mammalian target of rapamycin-driven pathways that modulated hepatocyte survival by coordinating apoptosis and autophagy. The signaling activity of α-ketoglutarate and the associated metabolites also affected methylation-related epigenomic remodeling enzymes. Integrative analysis of hepatic transcriptome signatures and differentially methylated genomic regions distinguished patients with and without steatohepatitis. CONCLUSION: We provide evidence supporting the multifaceted potential of the increased glutaminolysis-induced α-ketoglutarate production and the mammalian target of rapamycin complex 1 dysregulation as a conceivable source of the inefficient adaptive responses leading to steatohepatitis. LAY SUMMARY: Steatohepatitis is a frequent and threatening complication of extreme obesity without specific treatment. Omics technologies can be used to identify therapeutic targets. We highlight increased glutaminolysis-induced α-ketoglutarate production as a potential source of signals promoting and exacerbating steatohepatitis.

10.
Pathobiology ; 88(6): 392-399, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34407541

RESUMO

BACKGROUND: Colorectal cancer screening programs have accomplished a mortality reduction from the disease but have created bottlenecks in endoscopy units and pathology departments. We aimed to explore the feasibility of ex vivo fusion confocal microscopy (FuCM) to improve the histopathology diagnostic efficiency and reduce laboratory workload. METHODS: Consecutive fresh polyps removed at colonoscopy were scanned using ex vivo FuCM, then went through histopathologic workout and hematoxylin and eosin (H&E) diagnosis. Two pathologists blinded to H&E diagnosis made a diagnosis based on FuCM scanned images. RESULTS: Thirty-six fresh polyps from 22 patients were diagnosed with FuCM and H&E. Diagnostic agreement between H&E and FuCM was 97.2% (kappa = 0.96) for pathologist #1 and 91.7% (kappa = 0.87) for pathologist #2. Diagnostic performance concordance between FuCM and H&E to discern adenomatous from nonadenomatous polyps was 100% (kappa = 1) for pathologist #1 and 97.2% (kappa = 0.94) for pathologist #2. Global interobserver agreement was 94.44% (kappa = 0.91) and kappa = 0.94 to distinguish adenomatous from nonadenomatous polyps. CONCLUSIONS: Ex vivo FuCM shows an excellent correlation with standard H&E for the diagnosis of colorectal polyps. The clinical direct benefit for patients, pathologists, and endoscopists allows adapting personalized surveillance protocols after colonoscopy and a workload decrease in pathology departments.


Assuntos
Adenoma , Pólipos do Colo , Neoplasias Colorretais , Pólipos do Colo/diagnóstico , Colonoscopia , Neoplasias Colorretais/diagnóstico por imagem , Humanos , Microscopia Confocal
11.
Cytokine ; 126: 154923, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31739217

RESUMO

Chemokines, particularly chemokine (C-C- motif) ligand 2 (CCL2), control leukocyte migration into the wall of the artery and regulate the traffic of inflammatory cells. CCL2 is bound to functional receptors (CCR2), but also to atypical chemokine receptors (ACKRs), which do not induce cell migration but can modify chemokine gradients. Whether atherosclerosis alters CCL2 function by influencing the expression of these receptors remains unknown. In a necropsy study, we used immunohistochemistry to explore where and to what extent CCL2 and related receptors are present in diseased arteries that caused the death of men with coronary artery disease compared with unaffected arteries. CCL2 was marginally detected in normal arteries but was more frequently found in the intima. The expression of CCL2 and related receptors was significantly increased in diseased arteries with relative differences among the artery layers. The highest relative increases were those of CCL2 and ACKR1. CCL2 expression was associated with a significant predictive value of atherosclerosis. Findings suggest the need for further insight into receptor specificity or activity and the interplay among chemokines. CCL2-associated conventional and atypical receptors are overexpressed in atherosclerotic arteries, and these may suggest new potential therapeutic targets to locally modify the overall anti-inflammatory response.


Assuntos
Aterosclerose/patologia , Quimiocina CCL2/metabolismo , Doença da Artéria Coronariana/patologia , Sistema do Grupo Sanguíneo Duffy/metabolismo , Receptores CCR2/metabolismo , Receptores de Superfície Celular/metabolismo , Adulto , Idoso , Humanos , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Receptores de Quimiocinas/metabolismo
12.
Phys Rev Lett ; 125(17): 177204, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33156667

RESUMO

Controlling magnetism, essential for a wide range of technologies, is impaired by the impossibility of generating a maximum of magnetic field in free space. Here, we propose a strategy based on negative permeability to overcome this stringent limitation. We experimentally demonstrate that an active magnetic metamaterial can emulate the field of a straight current wire at a distance. Our strategy leads to an unprecedented focusing of magnetic fields in empty space and enables the remote cancellation of magnetic sources, opening an avenue for manipulating magnetic fields in inaccessible regions.

13.
Gut ; 68(6): 1065-1075, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30108162

RESUMO

OBJECTIVE: Sorafenib is the standard systemic therapy for advanced hepatocellular carcinoma (HCC). Survival benefits of resection/local ablation for early HCC are compromised by 70% 5-year recurrence rates. The phase 3 STORM trial comparing sorafenib with placebo as adjuvant treatment did not achieve its primary endpoint of improving recurrence-free survival (RFS). The biomarker companion study BIOSTORM aims to define (A) predictors of recurrence prevention with sorafenib and (B) prognostic factors with B level of evidence. DESIGN: Tumour tissue from 188 patients randomised to receive sorafenib (83) or placebo (105) in the STORM trial was collected. Analyses included gene expression profiling, targeted exome sequencing (19 known oncodrivers), immunohistochemistry (pERK, pVEGFR2, Ki67), fluorescence in situ hybridisation (VEGFA) and immunome. A gene signature capturing improved RFS in sorafenib-treated patients was generated. All 70 RFS events were recurrences, thus time to recurrence equalled RFS. Predictive and prognostic value was assessed using Cox regression models and interaction test. RESULTS: BIOSTORM recapitulates clinicopathological characteristics of STORM. None of the biomarkers tested (related to angiogenesis and proliferation) or previously proposed gene signatures, or mutations predicted sorafenib benefit or recurrence. A newly generated 146-gene signature identifying 30% of patients captured benefit to sorafenib in terms of RFS (p of interaction=0.04). These sorafenib RFS responders were significantly enriched in CD4+ T, B and cytolytic natural killer cells, and lacked activated adaptive immune components. Hepatocytic pERK (HR=2.41; p=0.012) and microvascular invasion (HR=2.09; p=0.017) were independent prognostic factors. CONCLUSION: In BIOSTORM, only hepatocytic pERK and microvascular invasion predicted poor RFS. No mutation, gene amplification or previously proposed gene signatures predicted sorafenib benefit. A newly generated multigene signature associated with improved RFS on sorafenib warrants further validation. TRIAL REGISTRATION NUMBER: NCT00692770.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/mortalidade , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Recidiva Local de Neoplasia/patologia , Sorafenibe/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Quimioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular/métodos , Invasividade Neoplásica/patologia , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/terapia , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Análise de Sobrevida , Inclusão do Tecido , Resultado do Tratamento
14.
Int J Cancer ; 144(3): 513-524, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30350313

RESUMO

Somatically acquired uniparental disomies (aUPDs) are frequent events in solid tumors and have been associated with cancer-related genes. Studies assessing their functional consequences across several cancer types are therefore necessary. Here, we aimed at integrating aUPD profiles with the mutational status of cancer-related genes in a tumor-type specific manner. Using TCGA datasets for 1,032 gastrointestinal cancers, including colon (COAD), rectum (READ), stomach (STAD), esophageal adenocarcinoma (EAC) and esophageal squamous cell carcinoma (ESCC), we show a non-random distribution of aUPD, suggesting the existence of a cancer-specific landscape of aUPD events. Our analysis indicates that aUPD acts as a "second hit" in Knudson's model in order to achieve biallelic inactivation of tumor suppressor genes. In particular, APC, ARID1A and NOTCH1 were recurrently inactivated by the presence of homozygous mutation as a consequence of aUPD in COAD and READ, STAD and ESCC, respectively. Furthermore, while TP53 showed inactivation caused by aUPD at chromosome arm 17p across all tumor types, copy number losses at this genomic position were also frequent. By experimental and computationally inferring genome ploidy, we demonstrate that an increased number of aUPD events, both affecting the whole chromosome or segments of it, were present in highly aneuploid genomes compared to near-diploid tumors. Finally, the presence of mosaic UPD was detected at a higher frequency in DNA extracted from peripheral blood lymphocytes of patients with colorectal cancer compared to healthy individuals. In summary, our study defines specific profiles of aUPD in gastrointestinal cancers and provides unequivocal evidence of their relevance in cancer.


Assuntos
Neoplasias Gastrointestinais/genética , Dissomia Uniparental/genética , Aneuploidia , Estudos de Casos e Controles , Análise Mutacional de DNA , Neoplasias Gastrointestinais/patologia , Perfil Genético , Estudo de Associação Genômica Ampla , Humanos , Polimorfismo de Nucleotídeo Único , Análise Serial de Tecidos , Dissomia Uniparental/patologia
15.
FASEB J ; 32(7): 3502-3517, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29452566

RESUMO

A considerable proportion of tumors exhibit aneuploid karyotypes, likely resulting from the progressive loss of chromosomes after whole-genome duplication. Here, by using isogenic diploid and near-tetraploid (4N) single-cell-derived clones from the same parental cell lines, we aimed at exploring how polyploidization affects cellular functions and how tetraploidy generates chromosome instability. Gene expression profiling in 4N clones revealed a significant enrichment of transcripts involved in cell cycle and DNA replication. Increased levels of replication stress in 4N cells resulted in DNA damage, impaired proliferation caused by a cell cycle delay during S phase, and higher sensitivity to S phase checkpoint inhibitors. In fact, increased levels of replication stress were also observed in nontransformed, proliferative posttetraploid RPE1 cells. Additionally, replication stress promoted higher levels of intercellular genomic heterogeneity and ongoing genomic instability, which could be explained by high rates of mitotic defects, and was alleviated by the supplementation of exogenous nucleosides. Finally, our data found that 4N cancer cells displayed increased migratory and invasive capacity, both in vitro and in primary colorectal tumors, indicating that tetraploidy can promote aggressive cancer cell behavior.-Wangsa, D., Quintanilla, I., Torabi, K., Vila-Casadesús, M., Ercilla, A., Klus, G., Yuce, Z., Galofré, C., Cuatrecasas, M., Lozano, J. J., Agell, N., Cimini, D., Castells, A., Ried, T., Camps, J. Near-tetraploid cancer cells show chromosome instability triggered by replication stress and exhibit enhanced invasiveness.


Assuntos
Movimento Celular , Instabilidade Cromossômica , Dano ao DNA , Neoplasias/genética , Tetraploidia , Linhagem Celular Tumoral , Replicação do DNA , Humanos , Fase S
16.
Int J Mol Sci ; 20(5)2019 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-30841538

RESUMO

Progressive muscle degeneration followed by dilated cardiomyopathy is a hallmark of muscular dystrophy. Stem cell therapy is suggested to replace diseased myofibers by healthy myofibers, although so far, we are faced by low efficiencies of migration and engraftment of stem cells. Chemokines are signalling proteins guiding cell migration and have been shown to tightly regulate muscle tissue repair. We sought to determine which chemokines are expressed in dystrophic muscles undergoing tissue remodelling. Therefore, we analysed the expression of chemokines and chemokine receptors in skeletal and cardiac muscles from Sarcoglycan-α null, Sarcoglycan-ß null and immunodeficient Sgcß-null mice. We found that several chemokines are dysregulated in dystrophic muscles. We further show that one of these, platelet-derived growth factor-B, promotes interstitial stem cell migration. This finding provides perspective to an approachable mechanism for improving stem cell homing towards dystrophic muscles.


Assuntos
Movimento Celular , Distrofia Muscular do Cíngulo dos Membros/metabolismo , Mioblastos/metabolismo , Proteínas Proto-Oncogênicas c-sis/metabolismo , Animais , Células Cultivadas , Quimiocinas/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Mioblastos/fisiologia , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Sarcoglicanas/genética , Sarcoglicanas/metabolismo
17.
Genes Chromosomes Cancer ; 57(3): 140-149, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29119627

RESUMO

To understand the molecular mechanism of rectal cancer and develop markers for disease prognostication, we generated and explored a dataset from 243 rectal cancer patients by gene expression microarray analysis of cancer samples and matched controls, and SNP-arrays of germline DNA. We found that two of the loci most strongly linked with colorectal cancer (CRC) risk, 8q24 (upstream of MYC) and 18q21 (in the intron of SMAD7), as well as 20q13 (in the intron of LAMA5), are tightly associated with the prognosis of rectal cancer patients. For SNPs on 18q21 (rs12953717 and rs4464148) and 20q13 (rs4925386), alleles that correlate with higher risk for the development of CRC are associated with shorter disease free survival (DFS). However, for rs6983267 on 8q24, the low risk allele is associated with a higher risk for recurrence and metastasis after surgery, and importantly, is strongly correlated with the resistance of CRC cell lines to chemoradiotherapy (CRT). We also found that although MYC expression is dramatically increased in cancer, patients with higher levels of MYC have a better prognosis. The expression of SMAD7 is weakly correlated with DFS. Notably, the presence of the 8q24 and 18q21 SNP alleles is not correlated with expression levels of MYC and SMAD7. rs4464148, and probably rs6983267 and rs4925386, are linked with overall survival time of patients. In conclusion, we show that several CRC risk SNPs detect subpopulations of rectal cancer patients with poor prognosis, and that rs6983267 probably affects prognosis through interfering with the resistance of cancer cells to CRT.


Assuntos
Neoplasias Colorretais/genética , Idoso , Alelos , Cromossomos Humanos Par 18/genética , Cromossomos Humanos Par 8/genética , Neoplasias do Colo/genética , Neoplasias Colorretais/cirurgia , Feminino , Predisposição Genética para Doença/genética , Testes Genéticos/métodos , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Polimorfismo de Nucleotídeo Único/genética , Prognóstico , Neoplasias Retais/genética , Fatores de Risco , Proteína Smad7/genética , Transcriptoma/genética
18.
Carcinogenesis ; 39(8): 993-1005, 2018 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-29800151

RESUMO

Intratumor heterogeneity is a major challenge in cancer treatment. To decipher patterns of chromosomal heterogeneity, we analyzed six colorectal cancer cell lines by multiplex interphase FISH (miFISH). The mismatch-repair-deficient cell lines DLD-1 and HCT116 had the most stable copy numbers, whereas aneuploid cell lines (HT-29, SW480, SW620 and H508) displayed a higher degree of instability. We subsequently assessed the clonal evolution of single cells in two colorectal carcinoma cell lines, SW480 and HT-29, which both have aneuploid karyotypes but different degrees of chromosomal instability. The clonal compositions of the single cell-derived daughter lines, as assessed by miFISH, differed for HT-29 and SW480. Daughters of HT-29 were stable, clonal, with little heterogeneity. Daughters of SW480 were more heterogeneous, with the single cell-derived daughter lines separating into two distinct populations with different ploidy (hyper-diploid and near-triploid), morphology, gene expression and tumorigenicity. To better understand the evolutionary trajectory for the two SW480 populations, we constructed phylogenetic trees which showed ongoing instability in the daughter lines. When analyzing the evolutionary development over time, most single cell-derived daughter lines maintained their major clonal pattern, with the exception of one daughter line that showed a switch involving a loss of APC. Our meticulous analysis of the clonal evolution and composition of these colorectal cancer models shows that all chromosomes are subject to segregation errors, however, specific net genomic imbalances are maintained. Karyotype evolution is driven by the necessity to arrive at and maintain a specific plateau of chromosomal copy numbers as the drivers of carcinogenesis.


Assuntos
Carcinogênese/genética , Neoplasias Colorretais/genética , Evolução Molecular , Linhagem Celular Tumoral , Instabilidade Cromossômica , Aberrações Cromossômicas , Evolução Clonal , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Cariótipo , Filogenia
19.
J Cell Physiol ; 233(2): 849-855, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28063221

RESUMO

Currently, a liver biopsy remains the only reliable way to precisely diagnose non-alcoholic fatty liver disease (NAFLD) and establish the severity of liver injury, presence of fibrosis, and architecture remodeling. However, the cost and the intrinsic invasive procedure of a liver biopsy rules it out as a gold standard diagnostic test, and the imaging test are not the best choice due to the price, and currently is being refined. The lack of a biomarker of NAFLD pushes to develop this new line of research. The aim of the present systematic review is to clarify and update all the NAFLD biomarkers described in the literature until recently. We highlight α-ketoglutarate and CK18-F as currently the best potential biomarker of NAFLD. However, due to methodological differences, we propose the implementation of international, multicenter, multiethnic studies with larger population size, and biopsy proven NAFLD diagnosis to analyze and compare α-ketoglutarate and CK18-F as potential biomarkers of the silent evolution of NAFLD.


Assuntos
Queratina-18/sangue , Ácidos Cetoglutáricos/sangue , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/sangue , Animais , Biomarcadores/sangue , Biópsia , Humanos , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes
20.
Chromosoma ; 126(5): 655-667, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28343235

RESUMO

Human chromosomes occupy distinct territories in the interphase nucleus. Such chromosome territories (CTs) are positioned according to gene density. Gene-rich CTs are generally located in the center of the nucleus, while gene-poor CTs are positioned more towards the nuclear periphery. However, the association between gene expression levels and the radial positioning of genes within the CT is still under debate. In the present study, we performed three-dimensional fluorescence in situ hybridization experiments in the colorectal cancer cell lines DLD-1 and LoVo using whole chromosome painting probes for chromosomes 8 and 11 and BAC clones targeting four genes with different expression levels assessed by gene expression arrays and RT-PCR. Our results confirmed that the two over-expressed genes, MYC on chromosome 8 and CCND1 on chromosome 11, are located significantly further away from the center of the CT compared to under-expressed genes on the same chromosomes, i.e., DLC1 and SCN3B. When CCND1 expression was reduced after silencing the major transcription factor of the WNT/ß-catenin signaling pathway, TCF7L2, the gene was repositioned and mostly detected in the interior of the CT. Thus, we suggest a non-random distribution in which over-expressed genes are located more towards the periphery of the respective CTs.


Assuntos
Núcleo Celular/metabolismo , Cromossomos Humanos/metabolismo , Interfase , Transdução de Sinais , Proteína 2 Semelhante ao Fator 7 de Transcrição/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/genética , Cromossomos Humanos/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Regulação da Expressão Gênica , Humanos , Hibridização in Situ Fluorescente
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