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1.
Int J Mol Sci ; 24(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36674892

RESUMO

Renal vasculature, which is highly innervated by sympathetic fibers, contributes to cardiovascular homeostasis. This renal sympathetic outflow is inhibited by 5-HT in normoglycaemic rats. Considering that diabetes induces cardiovascular complications, we aimed to determine whether diabetic state modifies noradrenergic input at renal level and its serotonergic modulation in rats. Alloxan diabetic rats were anaesthetized (pentobarbital; 60 mg/kg i.p.) and prepared for in situ autoperfusion of the left kidney to continuously measure systemic blood pressure (SBP), heart rate (HR), and renal perfusion pressure (RPP). Electrical stimulation of renal sympathetic outflow induces frequency-dependent increases (Δ) in RPP (23.9 ± 2.1, 59.5 ± 1.9, and 80.5 ± 3.5 mm Hg at 2, 4, and 6 Hz, respectively), which were higher than in normoglycaemic rats, without modifying HR or SBP. Intraarterial bolus of 5-HT and 5-CT (5-HT1/5/7 agonist) reduced electrically induced ΔRPP. Only L-694,247 (5-HT1D agonist) reproduced 5-CT inhibition on sympathetic-induced vasoconstrictions, whereas it did not modify exogenous noradrenaline-induced ΔRPP. 5-CT inhibition was exclusively abolished by i.v. bolus of LY310762 (5-HT1D antagonist). An inhibitor of guanylyl cyclase, ODQ (i.v.), completely reversed the L-694,247 inhibitory effect. In conclusion, diabetes induces an enhancement in sympathetic-induced vasopressor responses at the renal level. Prejunctional 5-HT1D receptors, via the nitric oxide pathway, inhibit noradrenergic-induced vasoconstrictions in diabetic rats.


Assuntos
Diabetes Mellitus Experimental , Serotonina , Ratos , Animais , Serotonina/metabolismo , Ratos Wistar , Receptor 5-HT1D de Serotonina/metabolismo , Diabetes Mellitus Experimental/metabolismo , Rim , Norepinefrina/farmacologia , Norepinefrina/metabolismo , Sistema Nervoso Simpático/metabolismo , Estimulação Elétrica , Pressão Sanguínea
2.
Doc Ophthalmol ; 138(1): 71-76, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30565057

RESUMO

PURPOSE: To describe the first case of a combined sub-hyaloid and sub-internal limiting membrane macular hemorrhage after recreational laser exposure. METHODS: A 23-year-old patient presented with an acute loss of vision in his right eye (OD) immediately after a brief exposure to a laser beam at a music festival. Color photography, spectral-domain optical coherence tomography (SD-OCT), and multifocal electroretinogram (mfERG) were performed for diagnosis and follow-up. RESULTS: On presentation, visual acuity was 20/400 in the OD and 20/20 in the left eye. Posterior segment examination of his OD revealed a preretinal hemorrhage at the macula. SD-OCT images exposed a combined sub-hyaloid and sub-internal limiting membrane localization. Successful VPP with ILM peeling was carried out. Although sequential mfERG displayed almost complete restoration of the P1 amplitude 6 months posterior to VPP, SD-OCT demonstrated permanent damage to outer retinal layers. Final BCVA on OD was 20/30. CONCLUSION: The expanding and unregulated use of lasers in everyday life has created an increasing amount of cases of laser-induced retinopathy in recent years. Much more attention should be addressed in laser safety and awareness to prevent future ocular injuries. In acute phases of sub-hyaloid hemorrhages blocking direct visualization of the posterior pole, mfERG is a valuable tool to address initial macular pathology.


Assuntos
Traumatismos Oculares/etiologia , Lasers/efeitos adversos , Retina/lesões , Hemorragia Retiniana/etiologia , Corpo Vítreo/lesões , Hemorragia Vítrea/etiologia , Eletrorretinografia , Traumatismos Oculares/diagnóstico por imagem , Traumatismos Oculares/cirurgia , Férias e Feriados , Humanos , Masculino , Hemorragia Retiniana/diagnóstico por imagem , Hemorragia Retiniana/cirurgia , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia , Vitrectomia , Hemorragia Vítrea/diagnóstico por imagem , Hemorragia Vítrea/cirurgia , Adulto Jovem
3.
Adv Anat Pathol ; 21(1): 44-62, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24316910

RESUMO

Ewing Sarcoma is a developmental tumor characterized by balanced chromosomal translocations and formation of new fusion genes, which are the main hallmark of this rare entity. Despite the vast knowledge regarding the molecular aspects of this rare malignancy obtained in the last few years, including the discovery of new therapeutic targets, many questions still remain open. In this review we focus on the research on targeted therapies in this malignancy, and discussed some bottlenecks related to this such as the possible role of pathologists, the availability of samples, the lack of appropriate animal models, and the resources needed to carry out preclinical and clinical research.


Assuntos
Neoplasias Ósseas/terapia , Terapia de Alvo Molecular/métodos , Sarcoma de Ewing/terapia , Animais , Neoplasias Ósseas/genética , Modelos Animais de Doenças , Humanos , Sarcoma de Ewing/genética , Terapias em Estudo
4.
Carcinogenesis ; 34(2): 268-76, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23108190

RESUMO

Neuroblastic tumors (NTs) include the neuroblastomas, ganglioneuroblastomas and ganglioneuromas. We have reported previously that the calcium-sensing receptor is expressed in differentiated, favorable NTs but almost undetectable in unfavorable neuroblastomas. We have now detected hypermethylation of a particular region within the CpG island encompassing the CaSR gene promoter 2 in neuroblastoma cell lines and 25% primary neuroblastomas. Hypermethylation of this region was associated with reduced CaSR messenger RNA expression and several predictors of poor outcome in neuroblastomas, including MYCN amplification. Treatment with 5'aza-2-deoxycitidine and/or trichostatin A restored CaSR expression in MYCN-amplified cell lines. Following 5'aza-2-deoxycitidine exposure, decreased percentages of methylated CpG sites were observed at the above-mentioned region. By interphase fluorescence in situ hybridization, variable percentages of nuclei with monosomy of chromosome 3, where the human CaSR gene resides, were observed in more than 90% of primary NTs of all subgroups. Nuclei harboring this alteration were heterogeneously distributed among tumor cells. Ectopic overexpression of the calcium-sensing receptor in two MYCN-amplified neuroblastoma cell lines in which this gene is silenced by promoter hypermethylation significantly reduced their in vitro proliferation rates and almost abolished their capacity to generate xenografts in immunocompromised mice. Finally, upon acute exposure to calcium, the primary activator of this receptor, calcium-sensing receptor-overexpressing neuroblastoma cells underwent apoptosis, a process dependent on sustained activation of ERK1/2. These data would support the hypothesis that epigenetic silencing of the CaSR gene is neither an in vitro artefact in neuroblastoma cell lines nor an irrelevant, secondary event in primary NTs, but a significant mechanism for neuroblastoma survival.


Assuntos
Apoptose , Metilação de DNA , Epigênese Genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neuroblastoma/patologia , Receptores de Detecção de Cálcio/genética , Glândulas Suprarrenais/metabolismo , Glândulas Suprarrenais/patologia , Animais , Western Blotting , Proliferação de Células , Ilhas de CpG , Feminino , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Imunoprecipitação , Hibridização in Situ Fluorescente , Lactente , Camundongos , Camundongos Nus , Monossomia , Proteína Proto-Oncogênica N-Myc , Estadiamento de Neoplasias , Neuroblastoma/genética , Neuroblastoma/mortalidade , Proteínas Nucleares/genética , Proteínas Oncogênicas/genética , Fosforilação , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Detecção de Cálcio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Foods ; 10(2)2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33557347

RESUMO

This study aims to determine the changes in, and bioaccessibility of, polyphenols and organosulfur compounds (OSCs) during the simulated gastrointestinal digestion of black onion, a novel product derived from fresh onion by a combination of heat and humidity treatment, and to compare it with its fresh counterpart. Fresh and black onions were subjected to in-vitro gastrointestinal digestion, and their polyphenol and OSC profiles were determined by ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-HRMS). Although to a lesser extent than in the fresh onion, the phenolic compounds in the black variety remained stable during the digestion process, presenting a higher bioaccessibility index (BI) with recovery corresponding to 41.1%, compared with that of fresh onion (23.5%). As for OSCs, apart from being more stable after the digestion process, with a BI of 83%, significantly higher quantities (21 times higher) were found in black onion than in fresh onion, suggesting that the black onion production process has a positive effect on the OSC content. Gallic acid, quercetin, isorhamnetin, and ɣ-glutamyl-S-(1-propenyl)-L-cysteine sulfoxide were the most bioaccessible compounds in fresh onion, while isorhamnetin, quercetin-diglucoside, ɣ-glutamyl-S-methyl-L-cysteine sulfoxide and methionine sulfoxide were found in black onion. These results indicate that OSCs and polyphenols are more bioaccessible in black onion than in fresh onion, indicating a positive effect of the processing treatment.

6.
CRISPR J ; 4(4): 519-535, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34406033

RESUMO

Chronic myeloid leukemia (CML) is a hematopoietic malignancy produced by a unique oncogenic event involving the constitutively active tyrosine-kinase (TK) BCR/ABL1. TK inhibitors (TKI) changed its prognosis and natural history. Unfortunately, ABL1 remains unaffected by TKIs. Leukemic stem cells (LSCs) remain, and resistant mutations arise during treatment. To address this problem, we have designed a therapeutic CRISPR-Cas9 deletion system targeting BCR/ABL1. The system was efficiently electroporated to cell lines, LSCs from a CML murine model, and LSCs from CML patients at diagnosis, generating a specific ABL1 null mutation at high efficiency and allowing the edited leukemic cells to be detected and tracked. The CRISPR-Cas9 deletion system triggered cell proliferation arrest and apoptosis in murine and human CML cell lines. Patient and murine-derived xenografts with CRISPR-edited LSCs in NOD SCID gamma niches revealed that normal multipotency and repopulation ability of CRISPR edited LSCs were fully restored. Normal hematopoiesis was restored, avoiding myeloid bias. To the best of our knowledge, we show for the first time how a CRISPR-Cas9 deletion system efficiently interrupts BCR/ABL1 oncogene in primary LSCs to bestow a therapeutic benefit. This study is a proof of concept for genome editing in all those diseases, like CML, sustained by a single oncogenic event, opening up new therapeutic opportunities.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Terapia Genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Oncogenes , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Proteínas de Fusão bcr-abl/genética , Expressão Gênica , Marcação de Genes/métodos , Técnicas de Transferência de Genes , Terapia Genética/métodos , Hematopoese/genética , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Xenoenxertos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Camundongos , Células-Tronco Neoplásicas/metabolismo , Estudo de Prova de Conceito
7.
PLoS One ; 16(7): e0254834, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34324551

RESUMO

Accumulation of misfolded proteins in the brain is a common hallmark of most age-related neurodegenerative diseases. Previous studies from our group identified the presence of anti-inflammatory and antioxidant compounds in leaves derived from the Chilean berry Ugni molinae (murtilla), in addition to show a potent anti-aggregation activity in models of Alzheimer´s disease. However, possible beneficial effects of berry extracts of murtilla was not investigated. Here we evaluated the efficacy of fruit extracts from different genotypes of Chilean-native U. molinae on reducing protein aggregation using cellular models of Huntington´s disease and assess the correlation with their chemical composition. Berry extraction was performed by exhaustive maceration with increasing-polarity solvents. An unbiased automatic microscopy platform was used for cytotoxicity and protein aggregation studies in HEK293 cells using polyglutamine-EGFP fusion proteins, followed by secondary validation using biochemical assays. Phenolic-rich extracts from murtilla berries of the 19-1 genotype (ETE 19-1) significantly reduced polyglutamine peptide aggregation levels, correlating with the modulation in the expression levels of autophagy-related proteins. Using LC-MS and molecular network analysis we correlated the presence of flavonoids, phenolic acids, and ellagitannins with the protective effects of ETE 19-1 effects on protein aggregation. Overall, our results indicate the presence of bioactive components in ethanolic extracts from U. molinae berries that reduce the load of protein aggregates in living cells.


Assuntos
Frutas , Doença de Huntington , Agregados Proteicos , Antioxidantes/farmacologia , Células HEK293 , Humanos , Myrtaceae/química , Extratos Vegetais/farmacologia , Folhas de Planta
8.
Blood Cancer J ; 11(7): 127, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244476

RESUMO

BIRC3 is monoallelically deleted in up to 80% of chronic lymphocytic leukemia (CLL) cases harboring del(11q). In addition, truncating mutations in the remaining allele of this gene can lead to BIRC3 biallelic inactivation, which has been shown to be a marker for reduced survival in CLL. Nevertheless, the biological mechanisms by which these lesions could contribute to del(11q) CLL pathogenesis and progression are partially unexplored. We implemented the CRISPR/Cas9-editing system to generate isogenic CLL cell lines harboring del(11q) and/or BIRC3 mutations, modeling monoallelic and biallelic BIRC3 loss. Our results reveal that monoallelic BIRC3 deletion in del(11q) cells promotes non-canonical NF-κB signaling activation via RelB-p52 nuclear translocation, being these effects allelic dose-dependent and therefore further enhanced in del(11q) cells with biallelic BIRC3 loss. Moreover, we demonstrate ex vivo in primary cells that del(11q) cases including BIRC3 within their deleted region show evidence of non-canonical NF-κB activation which correlates with high BCL2 levels and enhanced sensitivity to venetoclax. Furthermore, our results show that BIRC3 mutations in del(11q) cells promote clonal advantage in vitro and accelerate leukemic progression in an in vivo xenograft model. Altogether, this work highlights the biological bases underlying disease progression of del(11q) CLL patients harboring BIRC3 deletion and mutation.


Assuntos
Proteína 3 com Repetições IAP de Baculovírus/genética , Leucemia Linfocítica Crônica de Células B/genética , Alelos , Animais , Linhagem Celular Tumoral , Deleção Cromossômica , Progressão da Doença , Feminino , Humanos , Camundongos
9.
Clin Transl Med ; 11(2): e304, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33634999

RESUMO

BACKGROUND: Several genetic alterations have been identified as driver events in chronic lymphocytic leukemia (CLL) pathogenesis and oncogenic evolution. Concurrent driver alterations usually coexist within the same tumoral clone, but how the cooperation of multiple genomic abnormalities contributes to disease progression remains poorly understood. Specifically, the biological and clinical consequences of concurrent high-risk alterations such as del(11q)/ATM-mutations and del(17p)/TP53-mutations have not been established. METHODS: We integrated next-generation sequencing (NGS) and clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 techniques to characterize the in vitro and in vivo effects of concurrent monoallelic or biallelic ATM and/or TP53 alterations in CLL prognosis, clonal evolution, and therapy response. RESULTS: Targeted sequencing analysis of the co-occurrence of high-risk alterations in 271 CLLs revealed that biallelic inactivation of both ATM and TP53 was mutually exclusive, whereas monoallelic del(11q) and TP53 alterations significantly co-occurred in a subset of CLL patients with a highly adverse clinical outcome. We determined the biological effects of combined del(11q), ATM and/or TP53 mutations in CRISPR/Cas9-edited CLL cell lines. Our results showed that the combination of monoallelic del(11q) and TP53 mutations in CLL cells led to a clonal advantage in vitro and in in vivo clonal competition experiments, whereas CLL cells harboring biallelic ATM and TP53 loss failed to compete in in vivo xenotransplants. Furthermore, we demonstrated that CLL cell lines harboring del(11q) and TP53 mutations show only partial responses to B cell receptor signaling inhibitors, but may potentially benefit from ATR inhibition. CONCLUSIONS: Our work highlights that combined monoallelic del(11q) and TP53 alterations coordinately contribute to clonal advantage and shorter overall survival in CLL.


Assuntos
Leucemia Linfocítica Crônica de Células B/genética , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Deleção Cromossômica , Modelos Animais de Doenças , Progressão da Doença , Feminino , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Mutação/genética , Prognóstico
10.
Adv Anat Pathol ; 17(3): 162-81, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20418671

RESUMO

Bone and soft tissue sarcomas are an infrequent and heterogeneous group of mesenchymal tumors including more than a hundred different entities attending to histologic patterns. Research into the molecular aspects of sarcomas has increased greatly in the last few years. This enormous amount of knowledge has allowed, for instance, to refine the classification of sarcomas, improve the diagnosis, and increase the number of therapeutical targets available, most of them under preclinical evaluation. However, other important key issues, such as sarcomagenesis and the cell of origin of sarcomas, remain unresolved. From a molecular point of view, these neoplasias are grouped into 2 main types: (a) sarcomas showing relatively simple karyotypes and translocations, which originate gene fusions (eg, EWS-FLI1 in Ewing sarcoma) or point mutations (eg, c-kit in the gastrointestinal tumors) and (b) sarcomas showing unspecific gene alterations, very complex karyotypes, and no translocations. The discovery of the early mechanisms involved in the genesis of sarcomas, the more relevant signaling pathways, and the development of genetically engineered mouse models could also provide a new individualized therapeutic strategy against these tumors. This review describes the clinical application of some of the molecular alterations found in sarcomas, some advances in the field of sarcomagenesis, and the development of animal models.


Assuntos
Biologia Molecular/tendências , Sarcoma/genética , Neoplasias de Tecidos Moles/genética , Animais , Humanos
11.
Foods ; 9(11)2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33142731

RESUMO

Numerous studies have reported health benefits associated with the consumption of fresh and black garlic, which are characterized by the presence of polyphenols and organosulfur compounds (OS). This study aims to analyze the bioaccessibility of the bioactive compounds in fresh and black garlic after in vitro gastrointestinal digestion by monitoring the individual profile of these compounds by ultra-high-performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS). Polyphenols decreased from the beginning of the digestive process, is mainly affected during intestinal digestion. Regarding the OS, the S-alk(en)yl-L-cysteine (SACs) derivatives were more influenced by the acidic conditions of the gastric digestion, while the γ-glutamyl-S-alk(en)yl-L-cysteine (GSAk) derivatives were more susceptible to intestinal digestion conditions in both the fresh and black garlic samples. In conclusion, after in vitro gastrointestinal digestion, the compounds with the highest bioaccessibility were vanillic acid (69%), caffeic acid (52%), γ-glutamyl-S-methyl-L-cysteine sulfoxide (GSMCS) (77%), and S-allylmercapto-L-cysteine (SAMC) (329%) in fresh garlic. Meanwhile, in black garlic, the main bioaccessible compounds were caffeic acid (65%), GSMCS (89%), methionine sulfoxide (262%), trans-S-(1-propenyl)-L-cysteine (151%), and SAMC (106%). The treatment (heating + humidity) to obtain black garlic exerted a positive effect on the bioaccessibility of OS compounds, 55.3% of them remaining available in black garlic, but only 15% in fresh garlic. Polyphenols showed different behavior regarding bioaccessibility.

12.
Food Funct ; 11(5): 3986-4001, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32347279

RESUMO

This study explored plasma levels and urinary and fecal excretion of metabolites and microbial-derived catabolites over a 24 h period following the ingestion of red wine (RWP) or grape seed (GSP) proanthocyanidin-rich extracts by rats. In total, 35 structurally-related (epi)catechin metabolites (SREMs) and 5-carbon side chain ring fission metabolites (5C-RFMs) (phenyl-γ-valerolactones and phenylvaleric acids), and 50 phenolic acid and aromatic catabolites were detected after intakes of both extracts. The consumption of the RWP extract, but not the GSP extract, led to the appearance of a ∼200 nmol L-1 peak plasma concentration of SREMs formed from flavan-3-ol monomers. In contrast, ingestion of the GSPs, but not the RWPs, resulted in a substantial increase in microbiota-derived 5-carbon side chain ring fission metabolites (5C-RFMs) in plasma. 5C-RFMs, along with low molecular weight phenolic catabolites were detected in urine after ingestion of both extracts. The GSP and RWP extracts had respective mean degrees of polymerisation 5.9 and 6.5 subunits, and the RWP extract had an upper polymer size of 21 subunits compared to 44 subunits for the GSP extract. The differences in plasma metabolite profiles might, therefore, be a consequence of this polydispersity impacting on the microbiota-mediated rates of cleavage of the proanthocyanidin subunits and their subsequent metabolism and absorption. Urinary excretion of phenolic catabolites indicated that 11% of RWPs and 7% for GSPs were subjected to microbial degradation. In all probability these figures, rather than representing the percentage of proanthocyanidins that are completely degraded, indicate partial cleavage of monomer subunits producing a much higher percentage of shortened proanthocyanidin chains. Obtaining more detailed information on the in vivo fate of proanthocyanidins is challenging because of the difficulties in analysing unabsorbed parent proanthocyanidins and their partially degraded flavan-3-ol subunit chains in feces. Further progress awaits the development of improved purification and analytical techniques for proanthocyanidins and their use in feeding studies, and in vitro fecal and bacterial incubations, with radio and/or stable isotope-labelled substrates.


Assuntos
Extrato de Sementes de Uva/química , Proantocianidinas/química , Vitis/química , Vinho/análise , Animais , Disponibilidade Biológica , Fezes/química , Masculino , Estrutura Molecular , Ratos , Ratos Sprague-Dawley
13.
Cells ; 9(1)2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31952221

RESUMO

BACKGROUND: The t(12;21)(p13;q22), which fuses ETV6 and RUNX1 genes, is the most common genetic abnormality in children with B-cell precursor acute lymphoblastic leukaemia. The implication of the fusion protein in leukemogenesis seems to be clear. However, its role in the maintenance of the disease continues to be controversial. METHODS: Generation of an in vitroETV6/RUNX1 knock out model using the CRISPR/Cas9 gene editing system. Functional characterization by RNA sequencing, proliferation assays, apoptosis and pharmacologic studies, and generation of edited-cell xenograft model. RESULTS: The expression of ETV6/RUNX1 fusion gene was completely eliminated, thus generating a powerful model on which to study the role of the fusion gene in leukemic cells. The loss of fusion gene expression led to the deregulation of biological processes affecting survival such as apoptosis resistance and cell proliferation capacity. Tumour cells showed higher levels of apoptosis, lower proliferation rate and a greater sensitivity to PI3K inhibitors in vitro along as a decrease in tumour growth in xenografts models after ETV6/RUNX1 fusion gene abrogation. CONCLUSIONS: ETV6/RUNX1 fusion protein seems to play an important role in the maintenance of the leukemic phenotype and could thus become a potential therapeutic target.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Modelos Biológicos , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Proteínas Proto-Oncogênicas c-ets/metabolismo , Proteínas Repressoras/metabolismo , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Proliferação de Células , Subunidade alfa 2 de Fator de Ligação ao Core/deficiência , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Edição de Genes , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Proteínas Proto-Oncogênicas c-ets/deficiência , Proteínas Proto-Oncogênicas c-ets/genética , Proteínas Repressoras/deficiência , Proteínas Repressoras/genética , Células Tumorais Cultivadas , Variante 6 da Proteína do Fator de Translocação ETS
14.
Leukemia ; 34(6): 1599-1612, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31974435

RESUMO

The deletion of 11q (del(11q)) invariably comprises ATM gene in chronic lymphocytic leukemia (CLL). Concomitant mutations in this gene in the remaining allele have been identified in 1/3 of CLL cases harboring del(11q), being the biallelic loss of ATM associated with adverse prognosis. Although the introduction of targeted BCR inhibition has significantly favored the outcomes of del(11q) patients, responses of patients harboring ATM functional loss through biallelic inactivation are unexplored, and the development of resistances to targeted therapies have been increasingly reported, urging the need to explore novel therapeutic approaches. Here, we generated isogenic CLL cell lines harboring del(11q) and ATM mutations through CRISPR/Cas9-based gene-editing. With these models, we uncovered a novel therapeutic vulnerability of del(11q)/ATM-mutated cells to dual BCR and PARP inhibition. Ex vivo studies in the presence of stromal stimulation on 38 CLL primary samples confirmed a synergistic action of the combination of olaparib and ibrutinib in del(11q)/ATM-mutated CLL patients. In addition, we showed that ibrutinib produced a homologous recombination repair impairment through RAD51 dysregulation, finding a synergistic link of both drugs in the DNA damage repair pathway. Our data provide a preclinical rationale for the use of this combination in CLL patients with this high-risk cytogenetic abnormality.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Proteínas Mutadas de Ataxia Telangiectasia/genética , Leucemia Linfocítica Crônica de Células B/genética , Mutagênese Sítio-Dirigida/métodos , Adenina/análogos & derivados , Animais , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Deleção Cromossômica , Cromossomos Humanos Par 11/genética , Sinergismo Farmacológico , Humanos , Camundongos , Mutação , Ftalazinas/farmacologia , Piperazinas/farmacologia , Piperidinas , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Proteínas Proto-Oncogênicas c-bcr/antagonistas & inibidores , Pirazóis/farmacologia , Pirimidinas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Clin Cancer Res ; 25(7): 2228-2240, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30420447

RESUMO

PURPOSE: Endoglin (ENG; CD105) is a coreceptor of the TGFß family that is highly expressed in proliferating endothelial cells. Often coopted by cancer cells, ENG can lead to neo-angiogenesis and vasculogenic mimicry in aggressive malignancies. It exists both as a transmembrane cell surface protein, where it primarily interacts with TGFß, and as a soluble matricellular protein (sENG) when cleaved by matrix metalloproteinase 14 (MMP14). High ENG expression has been associated with poor prognosis in Ewing sarcoma, an aggressive bone cancer that primarily occurs in adolescents and young adults. However, the therapeutic value of ENG targeting has not been fully explored in this disease. EXPERIMENTAL DESIGN: We characterized the expression pattern of transmembrane ENG, sENG, and MMP14 in preclinical and clinical samples. Subsequently, the antineoplastic potential of two novel ENG-targeting monoclonal antibody-drug conjugates (ADC), OMTX503 and OMTX703, which differed only by their drug payload (nigrin-b A chain and cytolysin, respectively), was assessed in cell lines and preclinical animal models of Ewing sarcoma. RESULTS: Both ADCs suppressed cell proliferation in proportion to the endogenous levels of ENG observed in vitro. Moreover, the ADCs significantly delayed tumor growth in Ewing sarcoma cell line-derived xenografts and patient-derived xenografts in a dose-dependent manner. CONCLUSIONS: Taken together, these studies demonstrate potent preclinical activity of first-in-class anti-ENG ADCs as a nascent strategy to eradicate Ewing sarcoma.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Neoplasias Ósseas/metabolismo , Endoglina/antagonistas & inibidores , Imunoconjugados/farmacologia , Sarcoma de Ewing/metabolismo , Animais , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/patologia , Linhagem Celular , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Expressão Gênica , Humanos , Metaloproteinase 14 da Matriz/genética , Metaloproteinase 14 da Matriz/metabolismo , Camundongos , Terapia de Alvo Molecular , Medicina de Precisão , Sarcoma de Ewing/tratamento farmacológico , Sarcoma de Ewing/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Semin Diagn Pathol ; 25(4): 304-16, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19013896

RESUMO

Bone and soft tissue sarcomas are an infrequent and heterogeneous group of mesenchymal tumors, including more than a hundred different entities attending to histological patterns. Sarcomas are quite resistant to conventional chemotherapy (anthracycline and ifosfamide) with the exception of some subtypes, such as Ewing's sarcoma (ES). New drugs with proved efficacy against sarcomas include taxanes, gemcitabine, and ET-743. Preclinical studies have also identified key molecular events leading to the progression and development of sarcomas which are good candidates to targeted therapy. Inhibitors of the tyrosine kinase receptors, such as IGF-1R, c-kit, PDGFR, VEGFR, or the mTOR signaling pathway, proteasome, angiogenesis, and stress response proteins are under clinical evaluation against sarcomas. ES, a tumor characterized by chromosomal translocations that originate gene fusions (EWS-FLI1, EWS-ERG), is an example of a good chemotherapy responder tumor whose survival rate shows a plateau in recent years. Preclinical studies have identified that new targets such as HSP90 are of relevance to ES. On the other hand, recent studies showed the role of cancer stem cells (CSCs) in sarcomas and the relevance of the identification of reliable molecular markers and possible therapeutic targets. New therapeutic approaches could be directed against CSCs. This review describes more recent targeted therapy in sarcomas, with special emphasis on ES and the role of CSCs. We also emphasize the role of high throughput proteomic techniques in identifying new therapeutic targets.


Assuntos
Antineoplásicos/farmacologia , Biomarcadores Tumorais , Sistemas de Liberação de Medicamentos/tendências , Sarcoma/tratamento farmacológico , Sarcoma/genética , Animais , Ensaios Clínicos como Assunto , Sistemas de Liberação de Medicamentos/métodos , Humanos , Células-Tronco Neoplásicas/fisiologia
17.
J Chromatogr A ; 1575: 100-112, 2018 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-30228007

RESUMO

The present study compared and validated two analytical methods, HPLC-HRMS, and GC-MS using MSTFA as derivatization agent, for the analysis of microbiota-derived phenolic acids and aromatic compounds accumulating in urine, collected over a 24 h period after the consumption of 500 mL of orange juice. In addition, purification procedures using SDB-L and HLB solid phase cartridges were compared when HPLC-HRMS technique was used. Both HPLC-HRMS and GC-MS methodologies were successfully validated in terms of specificity, sensitivity, limit of detection and quantification, recovery and matrix effects. HPLC-HRMS, unlike GC-MS, does not require sample derivatization prior to analysis. GC-MS was not suitable for the analysis of phenolic sulfate and glucuronide metabolites because of their lack of volatility. These phase II metabolites could, however, be analysed by HPLC-HRMS which, as a consequence, provided more detailed and complete information on the phenolic compounds derived from microbiota-mediated degradation of orange juice (poly)phenols. Furthermore, the use of SDB-L and HLB cartridges for sample purification prior to HPLC-HRMS analysis is suitable for free phenolics and glucuronide metabolites but not sulfate derivatives. These findings highlight that the use of an inappropriate analytical protocol can adversely affect studies on the bioavailability of dietary (poly)phenols in which microbiota-derived phenolic catabolites play an important role.


Assuntos
Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Urinálise/métodos , Urinálise/normas , Citrus sinensis/química , Sucos de Frutas e Vegetais/microbiologia , Glucuronídeos/metabolismo , Glucuronídeos/urina , Humanos , Limite de Detecção , Fenóis/metabolismo , Fenóis/urina , Urinálise/instrumentação
18.
Food Chem ; 252: 49-60, 2018 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-29478563

RESUMO

This study developed, optimized and validated an ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) method to identify and quantify metabolites and microbial-derived catabolites in urine, plasma and feces of rats following ingestion of 50 mg of a red wine proanthocyanidin-rich extract. The method was validated for specificity, linearity, limit of detection (LD) and quantification (LQ), intra-day and inter-day precision, recovery and matrix effects, which were determined for 34 compounds in the three biological matrices. After method validation, three parent flavan-3-ols, four 5-carbon side chain ring fission metabolites, and 27 phenolic acid and aromatic catabolites were quantified in plasma, urine and feces after red wine proanthocyanidin intake. These results establish the value of the UHPLC-HRMS protocol in obtaining a detailed picture of proanthocyanidin metabolites and their microbial-derived catabolites, along with their phase II metabolites, in biological fluids of rat, and potentially in human clinical studies designed to evaluate the bioavailability of dietary flavan-3-ols.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Fezes/química , Flavonoides/metabolismo , Espectrometria de Massas/métodos , Proantocianidinas/farmacologia , Vinho/análise , Animais , Disponibilidade Biológica , Flavonoides/sangue , Flavonoides/farmacocinética , Flavonoides/urina , Limite de Detecção , Masculino , Ratos
19.
Clin Cancer Res ; 12(11 Pt 1): 3532-40, 2006 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-16740780

RESUMO

PURPOSE: Ewing tumor cell survival and proliferation depends on several autocrine loops. Targeting these loops is a promising therapeutic approach. We recently showed the cytostatic role of imatinib, an inhibitor of the SCF-KIT loop, on Ewing tumor cells, and in this study, we intend to analyze the inhibition of the insulin-like growth factor I receptor (IGF1R) loop. EXPERIMENTAL DESIGN: We analyzed IGF1R blockade by ADW742, a small molecule specific for this receptor, alone and in combination with imatinib, vincristine, and doxorubicin on Ewing tumor cell lines. We studied the effect on proliferation, apoptosis, cell cycle, pathway phosphorylation, soft-agar growth, motility, and vascular endothelial growth factor expression levels. RESULTS: Treatment with ADW742 induced down-regulation of IGF1R/AKT/mammalian target of rapamycin (mTOR) phosphorylation, which was deeper in cell lines having higher IGF1R activation levels. Treatment also induced dose-dependent inhibition of cell proliferation (IC50 = 0.55-1.4 micromol/L), inducing a G1 phase blockage and apoptosis. Addition of imatinib to ADW742 synergistically augmented these effects and was especially effective in inhibiting AKT/mTOR phosphorylation and reducing vascular endothelial growth factor expression in cell lines having high IGF1R activation levels. Combination with usual chemotherapeutic agents vincristine and doxorubicin showed synergistic interactions. CONCLUSIONS: Inhibition of Ewing tumor cell proliferation by ADW742 is mediated through blockade of IGF1R signaling. Combination of ADW742 with imatinib, vincristine, and doxorubicin induces a significant reduction of tumor cell growth, mainly by the increase in apoptosis with a pattern depending on IGF1R activation levels. This study supports a potential role for ADW742 in the treatment of Ewing tumor and AKT/mTOR as a possible surrogate marker of response to therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Doxorrubicina/administração & dosagem , Piperazinas/administração & dosagem , Pirimidinas/administração & dosagem , Pirimidinas/farmacologia , Pirróis/farmacologia , Sarcoma de Ewing/tratamento farmacológico , Vincristina/administração & dosagem , Apoptose/efeitos dos fármacos , Benzamidas , Neoplasias Ósseas/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Fase G1/efeitos dos fármacos , Humanos , Mesilato de Imatinib , Fosforilação/efeitos dos fármacos , Proteínas Quinases/efeitos dos fármacos , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor IGF Tipo 1/metabolismo , Sarcoma de Ewing/metabolismo , Relação Estrutura-Atividade , Serina-Treonina Quinases TOR
20.
Oncotarget ; 8(16): 26027-26040, 2017 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-28212528

RESUMO

CRISPR/Cas9 technology was used to abrogate p210 oncoprotein expression in the Boff-p210 cell line, a pro-B line derived from interlukin-3-dependent Baf/3, that shows IL-3-independence arising from the constitutive expression of BCR-ABL p210. Using this approach, pools of Boff-p210-edited cells and single edited cell-derived clones were obtained and functionally studied in vitro. The loss of p210 expression in Boff-p210 cells resulted in the loss of ability to grow in the absence of IL-3, as the Baf/3 parental line, showing significantly increased apoptosis levels. Notably, in a single edited cell-derived clone carrying a frame-shift mutation that prevents p210 oncoprotein expression, the effects were even more drastic, resulting in cell death. These edited cells were injected subcutaneously in immunosuppressed mice and tumor growth was followed for three weeks. BCR/ABL-edited cells developed smaller tumors than those originating from unedited Boff-p210 parental cells. Interestingly, the single edited cell-derived clone was unable to develop tumors, similar to what is observed with the parental Baf/3 cell line.CRISPR/Cas9 genomic editing technology allows the ablation of the BCR/ABL fusion gene, causing an absence of oncoprotein expression, and blocking its tumorigenic effects in vitro and in the in vivo xenograft model of CML. The future application of this approach in in vivo models of CML will allow us to more accurately assess the value of CRISPR/Cas9 technology as a new therapeutic tool that overcomes resistance to the usual treatments for CML patients.


Assuntos
Sistemas CRISPR-Cas , Transformação Celular Neoplásica/genética , Proteínas de Fusão bcr-abl/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Animais , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Modelos Animais de Doenças , Feminino , Edição de Genes , Marcação de Genes , Genes Reporter , Xenoenxertos , Humanos , Camundongos , Mutação , Carga Tumoral/genética
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