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1.
Hum Mol Genet ; 23(2): 467-78, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24067531

RESUMO

Tumor-derived exosomes are emerging as local and systemic cell-to-cell mediators of oncogenic information through the horizontal transfer of mRNAs, microRNAs and proteins during tumorigenesis. The exosomal content has been described as biologically active when taken up by the recipient cell. Identifying the specific molecular cargo of exosomes will help to determine their function in specific steps of the tumorigenic process. Here we evaluate whether ΔNp73 is selectively packaged in tumor-derived exosomes, its function in the acceptor cells in vitro and in vivo and its prognosis potential in cancer. ΔNp73 messenger is enriched in tumor-derived exosomes, suggesting its active sorting in these microvesicles. We observed the transmission of this exosome cargo to different cell types and how it confers proliferation potential and chemoresistance to the acceptor cells in vitro and in animal models. Finally, our data support the potential prognostic value of exosomal ΔNp73 in colon cancer patients.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos , Exossomos/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , RNA Mensageiro/genética , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Feminino , Células HCT116 , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Prognóstico , RNA Mensageiro/metabolismo , Taxa de Sobrevida , Proteína Tumoral p73
2.
Eur J Endocrinol ; 190(1): 62-74, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38033321

RESUMO

OBJECTIVE: Metabolic profiling is a valuable tool to characterize tumor biology but remains largely unexplored in neuroendocrine tumors (NETs). Our aim was to comprehensively assess the metabolomic profile of NETs and identify novel prognostic biomarkers and dysregulated molecular pathways. DESIGN AND METHODS: Multiplatform untargeted metabolomic profiling (GC-MS, CE-MS, and LC-MS) was performed in plasma from 77 patients with G1-2 extra-pancreatic NETs enrolled in the AXINET trial (NCT01744249) (study cohort) and from 68 non-cancer individuals (control). The prognostic value of each differential metabolite (n = 155) in NET patients (P < .05) was analyzed by univariate and multivariate analyses adjusted for multiple testing and other confounding factors. Related pathways were explored by Metabolite Set Enrichment Analysis (MSEA) and Metabolite Pathway Analysis (MPA). RESULTS: Thirty-four metabolites were significantly associated with progression-free survival (PFS) (n = 16) and/or overall survival (OS) (n = 27). Thirteen metabolites remained significant independent prognostic factors in multivariate analysis, 3 of them with a significant impact on both PFS and OS. Unsupervised clustering of these 3 metabolites stratified patients in 3 distinct prognostic groups (1-year PFS of 71.1%, 47.7%, and 15.4% (P = .012); 5-year OS of 69.7%, 32.5%, and 27.7% (P = .003), respectively). The MSEA and MPA of the 13-metablolite signature identified methionine, porphyrin, and tryptophan metabolisms as the 3 most relevant dysregulated pathways associated with the prognosis of NETs. CONCLUSIONS: We identified a metabolomic signature that improves prognostic stratification of NET patients beyond classical prognostic factors for clinical decisions. The enriched metabolic pathways identified reveal novel tumor vulnerabilities that may foster the development of new therapeutic strategies for these patients.


Assuntos
Tumores Neuroendócrinos , Porfirinas , Humanos , Metabolômica , Metionina/uso terapêutico , Tumores Neuroendócrinos/patologia , Porfirinas/uso terapêutico , Triptofano , Estudos de Casos e Controles
3.
Mater Today Bio ; 19: 100593, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36923364

RESUMO

Topographical patterns are a powerful tool to study directional migration. Grooved substrates have been extensively used as in vitro models of aligned extracellular matrix fibers because they induce cell elongation, alignment, and migration through a phenomenon known as contact guidance. This process, which involves the orientation of focal adhesions, F-actin, and microtubule cytoskeleton along the direction of the grooves, has been primarily studied on hard materials of non-physiological stiffness. But how it unfolds when the stiffness of the grooves varies within the physiological range is less known. Here we show that substrate stiffness modulates the cellular response to topographical contact guidance. We find that for fibroblasts, while focal adhesions and actin respond to topography independently of the stiffness, microtubules show a stiffness-dependent response that regulates contact guidance. On the other hand, both clusters and single breast carcinoma epithelial cells display stiffness-dependent contact guidance, leading to more directional and efficient migration when increasing substrate stiffness. These results suggest that both matrix stiffening and alignment of extracellular matrix fibers cooperate during directional cell migration, and that the outcome differs between cell types depending on how they organize their cytoskeletons.

4.
Anal Chim Acta ; 1205: 339782, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35414388

RESUMO

Some inborn errors of metabolism and other diseases can result in increasing blood ammonium (hyperammonemia episodes), which can cause serious neurological complications in patients or even death. Early diagnosis, follow up and treatment are essential to minimize irreversible damages in brain. Currently, adequate analytical instrumentation for the necessary ammonium bedside determination is not available in all health centers but only in clinical laboratories of reference hospitals. We therefore have developed a low cost and portable potentiometric Point-of-Care microanalyzer (POC) to address this problem. It consists of a cyclic olefin copolymer-based microanalyzer, the size of a credit card and working in continuous flow, which integrates microfluidics, a gas-diffusion module and a potentiometric detection system. The analytical features achieved are a linear range from 30 to 1000 µmol L-1 NH4+, a detection limit of 18 µmol L-1 NH4+ and a required sample volume of 100 µL, which comply with the medical requirements. Plasma and blood samples are analyzed with no significant differences observed between ammonium concentrations obtained with both the proposed microanalyzer and the reference method. This demonstrates the value of the developed POC for bedside clinical applications.


Assuntos
Compostos de Amônio , Cicloparafinas , Humanos , Microfluídica , Sistemas Automatizados de Assistência Junto ao Leito , Potenciometria
5.
Cancers (Basel) ; 13(11)2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34072010

RESUMO

PURPOSE: High-throughput "-omic" technologies have enabled the detailed analysis of metabolic networks in several cancers, but NETs have not been explored to date. We aim to assess the metabolomic profile of NET patients to understand metabolic deregulation in these tumors and identify novel biomarkers with clinical potential. METHODS: Plasma samples from 77 NETs and 68 controls were profiled by GC-MS, CE-MS and LC-MS untargeted metabolomics. OPLS-DA was performed to evaluate metabolomic differences. Related pathways were explored using Metaboanalyst 4.0. Finally, ROC and OPLS-DA analyses were performed to select metabolites with biomarker potential. RESULTS: We identified 155 differential compounds between NETs and controls. We have detected an increase of bile acids, sugars, oxidized lipids and oxidized products from arachidonic acid and a decrease of carnitine levels in NETs. MPA/MSEA identified 32 enriched metabolic pathways in NETs related with the TCA cycle and amino acid metabolism. Finally, OPLS-DA and ROC analysis revealed 48 metabolites with diagnostic potential. CONCLUSIONS: This study provides, for the first time, a comprehensive metabolic profile of NET patients and identifies a distinctive metabolic signature in plasma of potential clinical use. A reduced set of metabolites of high diagnostic accuracy has been identified. Additionally, new enriched metabolic pathways annotated may open innovative avenues of clinical research.

6.
Prog Neuropsychopharmacol Biol Psychiatry ; 33(2): 367-72, 2009 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-19168113

RESUMO

Postmenopause is mainly characterized by a reduction of ovarian hormones, which is accompanied by a major incidence of physical disorders and mood swings. Clinical and experimental evidence suggest that phytoestrogens could be used to ameliorate these alterations associated with menopause. However, the phytoestrogen effects on anxiety in rats with long-term absence of ovarian hormones, is unknown. Consequently, in the present study the authors compared the anxiolytic-like effect of phytoestrogen genistein (0.25, 0.5 y 1.0 mg/kg, i.p.) in Wistar rats with 12-weeks postovariectomy in the black and white model and in the open field test, and it was compared with diazepam (1.0 mg/kg, i.p.). In the black and white model, genistein (0.5 y 1.0 mg/kg) and diazepam reduced the latency to enter and increased the time spent into the white compartment; also, significantly increased frequency and time spent in exploration toward white compartment was seen, as compared with the control group (p<0.05). In the open field test, genistein and diazepam increased grooming and rearing, without significant changes in locomotor activity, as compared with the control group. In conclusion, phytoestrogen genistein produces an anxiolytic-like effect in Wistar rats with long-term absence of ovarian hormones in the black and white model, supporting the hypotheses that phytoestrogens could be used to ameliorate anxiety associated with menopause.


Assuntos
Ansiolíticos , Estrogênios/metabolismo , Genisteína/farmacologia , Ovariectomia/psicologia , Fitoestrógenos/farmacologia , Animais , Diazepam/farmacologia , Feminino , Asseio Animal , Luz , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Wistar
7.
Reumatol Clin ; 12(5): 282-4, 2016.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26654571

RESUMO

Paraneoplastic syndromes can be presented in multiple ways, which include endocrinological, hematologic, rheumatologic and nephrologic manifestations. While most of the publications described solid tumors as responsible for these manifestations, hematologic neoplasms are important cause to consider as part of the differential diagnosis. We report the case of a 46 year-old man with seronegative symmetric polyarthritis of large and small joints associated with membranoproliferative glomerulonephritis with deposits of immune complexes and acute impairment of renal function, as part of a paraneoplastic syndrome secondary of a classical Hodgkin lymphoma with bone marrow invasion, which reversed completely with chemotherapy treatment.


Assuntos
Artrite/etiologia , Glomerulonefrite Membranoproliferativa/etiologia , Doença de Hodgkin/diagnóstico , Síndromes Paraneoplásicas/etiologia , Artrite/diagnóstico , Diagnóstico Diferencial , Glomerulonefrite Membranoproliferativa/diagnóstico , Doença de Hodgkin/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Paraneoplásicas/diagnóstico
8.
Clin Cancer Res ; 21(19): 4398-409, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26023082

RESUMO

BACKGROUND: The acquired resistance to chemotherapy represents the major limitation in the treatment of cancer. New strategies to solve this failure and improve patients' outcomes are necessary. The cancer preventive effect of ß-cryptoxanthin has been widely described in population studies. Few reports support its putative use as an antitumoral compound. Here we focus on the therapeutic potential of ß-cryptoxanthin individually or in combination with oxaliplatin in colon cancer and try to decipher the molecular basis underlying its effect. METHODS: Apoptosis, viability and proliferation assays, mouse models, and an intervention study in 20 healthy subjects were performed. A PCR array was carried out to unravel the molecular putative basis of the ß-cryptoxanthin effect, and further signaling experiments were conducted. Comet Assay was completed to evaluate the genotoxicity of the treatments. RESULTS: ß-Cryptoxanthin differentially regulates the expression of the P73 variants in vitro, in vivo, and in a human intervention study. This carotenoid decreases the proliferation of cancer cells and cooperates with oxaliplatin to induce apoptosis through the negative regulation of ΔNP73. The antitumoral concentrations of oxaliplatin decrease in the presence of ß-cryptoxanthin to achieve same percentage of growth inhibition. The genotoxicity in peripheral blood mononuclear cells of mice decreased in the combined treatment. CONCLUSIONS: We propose a putative novel therapeutic strategy for the treatment of colon cancer based on the combination of ß-cryptoxanthin and oxaliplatin. The combined regimen produced more benefit than either individual modality without increasing side effects. In addition, the concentration-limiting toxicity of oxaliplatin is reduced in the presence of the carotenoid.


Assuntos
Antineoplásicos/farmacologia , Neoplasias do Colo/genética , Criptoxantinas/farmacologia , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas Nucleares/genética , Compostos Organoplatínicos/farmacologia , Proteínas Supressoras de Tumor/genética , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Sinergismo Farmacológico , Feminino , Humanos , Camundongos , Proteínas Nucleares/metabolismo , Oxaliplatina , Isoformas de Proteínas , Proteína Tumoral p73 , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Oncotarget ; 6(38): 40575-87, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26528758

RESUMO

Cancer cells efficiently transfer exosome contents (essentially mRNAs and microRNAs) to other cell types, modifying immune responses, cell growth, angiogenesis and metastasis. Here we analyzed the exosomes release by breast tumor cells with different capacities of stemness/metastasis based on CXCR4 expression, and evaluated their capacity to generate oncogenic features in recipient cells. Breast cancer cells overexpressing CXCR4 showed an increase in stemness-related markers, and in proliferation, migration and invasion capacities. Furthermore, recipient cells treated with exosomes from CXCR4-cells showed increased in the same abilities. Moreover, inoculation of CXCR4-cell-derived exosomes in immunocompromised mice stimulated primary tumor growth and metastatic potential. Comparison of nucleic acids contained into exosomes isolated from patients revealed a "stemness and metastatic" signature in exosomes of patients with worse prognosis. Finally, our data supported the view that cancer cells with stem-like properties show concomitant metastatic behavior, and their exosomes stimulate tumor progression and metastasis. Exosomes-derived nucleic acids from plasma of breast cancer patients are suitable markers in the prognosis of such patients.


Assuntos
Neoplasias da Mama/patologia , Proliferação de Células , Transformação Celular Neoplásica/patologia , Exossomos/genética , Regulação Neoplásica da Expressão Gênica , Células-Tronco Neoplásicas/patologia , Receptores CXCR4/metabolismo , Animais , Apoptose , Western Blotting , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Movimento Celular , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Feminino , Humanos , Técnicas Imunoenzimáticas , Camundongos , Camundongos Nus , Metástase Neoplásica , Células-Tronco Neoplásicas/metabolismo , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores CXCR4/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
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