Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
Mais filtros

Base de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Proteomics ; 21(13-14): e2000119, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33580572

RESUMO

Circulating small extracellular vesicles (sEV) represent promising non-invasive biomarkers that may aid in the diagnosis and risk-stratification of multiple myeloma (MM), an incurable blood cancer. Here, we comprehensively isolated and characterized sEV from human MM cell lines (HMCL) and patient-derived plasma (psEV) by specific EV-marker enrichment and morphology. Importantly, we demonstrate that HMCL-sEV are readily internalised by stromal cells to functionally modulate proliferation. psEV were isolated using various commercial approaches and pre-analytical conditions (collection tube types, storage conditions) assessed for sEV yield and marker enrichment. Functionally, MM-psEV was shown to regulate stromal cell proliferation and migration. In turn, pre-educated stromal cells favour HMCL adhesion. psEV isolated from patients with both pre-malignant plasma cell disorders (monoclonal gammopathy of undetermined significance [MGUS]; smouldering MM [SMM]) and MM have a similar ability to promote cell migration and adhesion, suggesting a role for both malignant and pre-malignant sEV in disease progression. Proteomic profiling of MM-psEV (305 proteins) revealed enrichment of oncogenic factors implicated in cell migration and adhesion, in comparison to non-disease psEV. This study describes a protocol to generate morphologically-intact and biologically functional sEV capable of mediating the regulation of stromal cells, and a model for the characterization of tumour-stromal cross-talk by sEV in MM.


Assuntos
Vesículas Extracelulares , Gamopatia Monoclonal de Significância Indeterminada , Mieloma Múltiplo , Humanos , Proteômica , Células Estromais
2.
Br J Haematol ; 193(1): 160-170, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32945549

RESUMO

Panobinostat is a pan-deacetylase inhibitor that modulates the expression of oncogenic and immune-mediating genes involved in tumour cell growth and survival. We evaluated panobinostat-induced post-transplant responses and identified correlative biomarkers in patients with multiple myeloma who had failed to achieve a complete response after autologous transplantation. Patients received panobinostat 45 mg administered three-times weekly (TIW) on alternate weeks of 28-day cycles commencing 8-12 weeks post-transplant. Twelve of 25 patients (48%) improved their depth of response after a median (range) of 4·3 (1·9-9·7) months of panobinostat. In responders, T-lymphocyte histone acetylation increased after both three cycles (P < 0·05) and six cycles (P < 0·01) of panobinostat when compared to baseline, with no differences in non-responders. The reduction in the proportion of CD127+ CD8+ T cells and CD4:CD8 ratio was significantly greater, after three and six cycles of panobinostat compared to pre-transplant, in non-responders when compared to responders. Whole marrow RNA-seq revealed widespread transcriptional changes only in responders with baseline differences in genes involved in ribosome biogenesis, oxidative phosphorylation and metabolic pathways. This study confirmed the efficacy of panobinostat as a single agent in multiple myeloma and established acetylation of lymphocyte histones, modulation of immune subsets and transcriptional changes as pharmacodynamic biomarkers of clinical benefit.


Assuntos
Inibidores de Histona Desacetilases/uso terapêutico , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/terapia , Panobinostat/uso terapêutico , Transplante Autólogo/efeitos adversos , Adulto , Idoso , Antígenos CD4/efeitos dos fármacos , Antígenos CD4/imunologia , Antígenos CD8/efeitos dos fármacos , Antígenos CD8/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/patologia , Feminino , Seguimentos , Inibidores de Histona Desacetilases/administração & dosagem , Inibidores de Histona Desacetilases/efeitos adversos , Histonas/efeitos dos fármacos , Histonas/metabolismo , Humanos , Subunidade alfa de Receptor de Interleucina-7/efeitos dos fármacos , Subunidade alfa de Receptor de Interleucina-7/imunologia , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/mortalidade , Estadiamento de Neoplasias/métodos , Oncogenes/efeitos dos fármacos , Panobinostat/administração & dosagem , Panobinostat/efeitos adversos , Indução de Remissão , Análise de Sobrevida , Transplante Autólogo/estatística & dados numéricos , Resultado do Tratamento
3.
J Thromb Haemost ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38754782

RESUMO

BACKGROUND: Ischemic stroke is characterized by a necrotic lesion in the brain surrounded by an area of dying cells termed the penumbra. Salvaging the penumbra either with thrombolysis or mechanical retrieval is the cornerstone of stroke management. At-risk neuronal cells release extracellular adenosine triphosphate, triggering microglial activation and causing a thromboinflammatory response, culminating in endothelial activation and vascular disruption. This is further aggravated by ischemia-reperfusion injury that follows all reperfusion therapies. The ecto-enzyme CD39 regulates extracellular adenosine triphosphate by hydrolyzing it to adenosine, which has antithrombotic and anti-inflammatory properties and reverses ischemia-reperfusion injury. OBJECTIVES: The objective off the study was to determine the efficacy of our therapeutic, anti-VCAM-CD39 in ischaemic stroke. METHODS: We developed anti-VCAM-CD39 that targets the antithrombotic and anti-inflammatory properties of recombinant CD39 to the activated endothelium of the penumbra by binding to vascular cell adhesion molecule (VCAM)-1. Mice were subjected to 30 minutes of middle cerebral artery occlusion and analyzed at 24 hours. Anti-VCAM-CD39 or control agents (saline, nontargeted CD39, or anti-VCAM-inactive CD39) were given at 3 hours after middle cerebral artery occlusion. RESULTS: Anti-VCAM-CD39 treatment reduced neurologic deficit; magnetic resonance imaging confirmed significantly smaller infarcts together with an increase in cerebrovascular perfusion. Anti-VCAM-CD39 also restored blood-brain barrier integrity and reduced microglial activation. Coadministration of anti-VCAM-CD39 with thrombolytics (tissue plasminogen activator [tPA]) further reduced infarct volumes and attenuated blood-brain barrier permeability with no associated increase in intracranial hemorrhage. CONCLUSION: Anti-VCAM-CD39, uniquely targeted to endothelial cells, could be a new stroke therapy even when administered 3 hours postischemia and may further synergize with thrombolytic therapy to improve stroke outcomes.

4.
Cancers (Basel) ; 14(3)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35159107

RESUMO

Over the last three decades changes in the treatment paradigm for newly diagnosed multiple myeloma (MM) have led to a significant increase in overall survival. Despite this, the majority of patients relapse after one or more lines of treatment while acquiring resistance to available therapies. Panobinostat, a pan-histone deacetylase inhibitor, was approved by the FDA in 2015 for patients with relapsed MM but how to incorporate panobinostat most effectively into everyday practice remains unclear. Dysregulation of the Wnt canonical pathway, and its key mediator ß-catenin, has been shown to be important for the evolution of MM and the acquisition of drug resistance, making it a potentially attractive therapeutic target. Despite concerns regarding the safety of Wnt pathway inhibitors, we have recently shown that the ß-catenin inhibitor Tegavivint is deliverable and effective in in vivo models of MM. In this study we show that the combination of low concentrations of panobinostat and Tegavivint have significant in vitro and in vivo anti-MM effects including in the context of proteasome inhibitor resistance, by targeting both aerobic glycolysis and mitochondrial respiration and the down-regulation of down-stream ß-catenin targets including myc, cyclinD1, and cyclinD2. The significant anti-MM effect of this novel combination warrants further evaluation for the treatment of MM patients with relapsed and/or refractory MM.

5.
Br J Haematol ; 152(2): 164-74, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21118196

RESUMO

B-catenin is the central effector molecule of the canonical Wnt signalling pathway, which controls self-renewal of haematopoietic stem cells. Deregulation of this pathway occurs in various malignancies including myeloid leukaemias. The present study examined the functional outcome of stable ß-catenin down-regulation through lentivirus-mediated expression of short hairpin RNA (shRNA). Reduction of the ß-catenin levels in acute myeloid leukaemia (AML) cell lines and patient samples decelerated their in vitro proliferation ability without affecting cell viability. Transplantation of leukaemic cells with control or reduced levels of ß-catenin in non-obese diabetic severe combined immunodeficient animals indicated that, while the immediate homing of the cells was unaffected, the bone marrow engraftment was directly dependent on ß-catenin levels. Subsequent examination of bone sections revealed that ß-catenin was implicated in the localization of AML to the endosteum. Examination of adhesion molecule expression before and after transplantation, revealed down-regulation of CD44 expression, accompanied by reduced in vitro adhesion. Gene expression analysis disclosed the presence of an autocrine compensatory mechanism, which responds to the reduced ß-catenin levels by altering the expression of positive and negative pathway regulators. In conclusion, our study showed that ß-catenin comprises an integral part of AML cell proliferation, cell cycle progression, and adhesion, and influences disease establishment in vivo.


Assuntos
Leucemia Mieloide Aguda/patologia , Proteínas de Neoplasias/fisiologia , beta Catenina/fisiologia , Adulto , Idoso , Animais , Moléculas de Adesão Celular/metabolismo , Ciclo Celular/fisiologia , Proliferação de Células , Progressão da Doença , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Inativação Gênica , Sobrevivência de Enxerto/fisiologia , Humanos , Receptores de Hialuronatos/fisiologia , Leucemia Mieloide Aguda/metabolismo , Camundongos , Camundongos SCID , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Transplante de Neoplasias , Transplante Heterólogo , Células Tumorais Cultivadas , beta Catenina/metabolismo
6.
Leukemia ; 35(10): 2771-2783, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34262132

RESUMO

Liquid biopsies-a source of circulating cell-free nucleic acids, proteins and extracellular vesicles-are currently being explored for the quantitative and qualitative characterisation of the tumour genome and as a mode of non-invasive therapeutic monitoring in cancer. Emerging data suggest that liquid biopsies might offer a potentially simple, non-invasive, repeatable strategy for diagnosis, prognostication and therapeutic decision making in a genetically heterogeneous disease like multiple myeloma (MM), with particular applicability in subsets of patients where conventional markers of disease burden may be less informative. In this review, we describe the emerging utility of the evaluation of circulating tumour DNA, extracellular RNA, cell-free proteins and metabolites and extracellular vesicles in MM.


Assuntos
Biópsia Líquida/métodos , Plasmócitos/patologia , Animais , Biomarcadores Tumorais/sangue , Ácidos Nucleicos Livres/sangue , DNA Tumoral Circulante/sangue , Vesículas Extracelulares/patologia , Humanos , Mieloma Múltiplo/sangue , Mieloma Múltiplo/patologia , Células Neoplásicas Circulantes/patologia
7.
Leuk Lymphoma ; 62(2): 337-347, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33131357

RESUMO

Microarray was utilized to determine if a genetic signature associated with resistance to carfilzomib (CFZ) could be identified. Twelve human myeloma (MM) cell lines (HMCLs) were treated with CFZ and a cell-viability profile was assessed categorizing HMCLs as sensitive or resistant to CFZ. The gene expression profiles (GEP) of untreated resistant versus sensitive HMCLs revealed 29 differentially expressed genes. TOP2A, an enzyme involved in cell cycle and proliferation, was overexpressed in carfilzomib-resistant HMCLs. TOP2A protein expression levels, evaluated utilizing trephine biopsy specimens acquired prior to treatment with proteasome inhibitors, were higher in patients failing to achieve a response when compared to responding patients. Logistic-regression analysis confirmed that TOP2A protein expression was a highly significant predictor of response to PIs (AUC 0.738). Further, the combination of CFZ with TOP2A inhibitors, demonstrated synergistic cytotoxic effects in vitro, providing a rationale for combining topoisomerase inhibitors with CFZ to overcome resistance in MM.


Assuntos
Antineoplásicos , Mieloma Múltiplo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , DNA Topoisomerases Tipo II/genética , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Oligopeptídeos , Inibidores de Proteassoma/farmacologia , Inibidores de Proteassoma/uso terapêutico
8.
Anal Chem ; 81(20): 8596-602, 2009 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19824717

RESUMO

Unlike the inherited mutations, which are present in all cells, somatic (acquired) mutations occur only in certain cells of the body and, quite often, are oncogenic. Quantification of mutant allele burden (percentage of the mutant allele) is critical for diagnosis, monitoring of therapy, and detection of minimal residual disease. With point mutations, the challenge is to quantify the mutant allele while discriminating from a large excess of the normal allele that differs in a single base-pair. To this end, we report the first bioluminometric assay for quantification of the allele burden and its application to JAK2 V617F somatic point mutation, which is a recently (2005) discovered molecular marker for myeloproliferative neoplasms. The method is performed in microtiter wells and involves a single PCR, for amplification of both alleles, followed by primer extension reactions with allele-specific primers. The products are captured in microtiter wells and detected by oligo(dT)-conjugated photoprotein aequorin. The photoprotein is measured within seconds by simply adding Ca(2+). We have demonstrated that the percent (%) luminescence signal due to the mutant allele is linearly related to the allele burden. As low as 0.85% of mutant allele can be detected and the linearity extends to 100%. The assay is complete within 50 min after the amplification step.


Assuntos
Alelos , Janus Quinase 2/genética , Mutação Puntual , Equorina/metabolismo , Animais , Cálcio/metabolismo , Bovinos , Primers do DNA/genética , Humanos , Janus Quinase 2/metabolismo , Modelos Lineares , Medições Luminescentes , Magnésio/metabolismo , Reação em Cadeia da Polimerase
9.
Leukemia ; 33(8): 2022-2033, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30992504

RESUMO

Monitoring tumour burden and therapeutic response through analyses of circulating cell-free tumour DNA (ctDNA) and extracellular RNA (exRNA) in multiple myeloma (MM) patients were performed in a Phase Ib trial of 24 relapsed/refractory patients receiving oral azacitidine in combination with lenalidomide and dexamethasone. Mutational characterisation of paired BM and PL samples at study entry identified that patients with a higher number of mutations or a higher mutational fractional abundance in PL had significantly shorter overall survival (OS) (p = 0.005 and p = 0.018, respectively). A decrease in ctDNA levels at day 5 of cycle 1 of treatment (C1D5) correlated with superior progression-free survival (PFS) (p = 0.017). Evaluation of exRNA transcripts of candidate biomarkers indicated that high CRBN levels coupled with low levels of SPARC at baseline were associated with shorter OS (p = 0.000003). IKZF1 fold-change <0.05 at C1D5 was associated with shorter PFS (p = 0.0051) and OS (p = 0.0001). Furthermore, patients with high baseline CRBN coupled with low fold-change at C1D5 were at the highest risk of progression (p = 0.0001). In conclusion, this exploratory analysis has provided the first demonstration in MM of ctDNA for predicting disease outcome and of the utility of exRNA as a biomarker of therapeutic response.


Assuntos
DNA Tumoral Circulante/análise , Mieloma Múltiplo/tratamento farmacológico , RNA/análise , Proteínas Adaptadoras de Transdução de Sinal , Efeitos Psicossociais da Doença , Genes p53 , Humanos , Fator de Transcrição Ikaros/análise , Mieloma Múltiplo/sangue , Mieloma Múltiplo/genética , Mieloma Múltiplo/mortalidade , Mutação , Peptídeo Hidrolases/análise , Prognóstico , Ubiquitina-Proteína Ligases
10.
Eur J Haematol ; 80(2): 177-81, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18076638

RESUMO

Intravascular lymphoma is an extremely rare, disseminated, and aggressive extranodal CD20+ non-Hodgkin's lymphoma characterized by the presence of lymphoma cells only in the lumina of small vessels. We report a 72-year-old woman with a diagnosis of intravascular lymphoma presented with splenomegaly and leukemic appearance in the peripheral blood smear. Her clinical course was rapidly deteriorated before the initiation of specific chemotherapy and finally died due to multiorgan insufficiency. Bone marrow biopsy revealed a characteristic infiltration of CD5, CD10 B-cell lymphoma. To our knowledge, this is the first reported case of a CD5, CD10 intravascular B-cell lymphoma with leukemic presentation in peripheral blood with multiple cytogenetic aberrations.


Assuntos
Leucemia/complicações , Linfoma Difuso de Grandes Células B/complicações , Idoso , Antígenos CD20/biossíntese , Antígenos CD34/biossíntese , Biópsia , Medula Óssea/patologia , Antígenos CD5/biossíntese , Aberrações Cromossômicas , Evolução Fatal , Feminino , Humanos , Imuno-Histoquímica , Neprilisina/biossíntese , Esplenomegalia/tratamento farmacológico
11.
Mol Cancer Ther ; 16(9): 1765-1778, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28500235

RESUMO

Currently available treatment options are unlikely to be curative for the majority of multiple myeloma patients, emphasizing a continuing role for the introduction of investigational agents that can overcome drug resistance. The canonical Wnt/ß-catenin signaling pathway, essential for self-renewal, growth, and survival, has been found to be dysregulated in multiple myeloma, particularly in advanced stages of disease. This provides the rationale for evaluating the novel ß-catenin inhibitor BC2059 as monotherapy and in combination with proteasome inhibitors in vitro and in vivo Here, we show nuclear localization of ß-catenin in human myeloma cell lines (HMCL), consistent with activation of the canonical Wnt pathway. BC2059 attenuates ß-catenin levels, in both the cytoplasm and the nucleus, reducing the transcriptional activity of the TCF4/LEF complex and the expression of its target gene axin 2. Treatment of HMCL with BC2059 inhibits proliferation and induces apoptosis in a dose-dependent manner. This is also observed in HMCL-stromal cell cocultures, mitigating the protective effect afforded by the stroma. Similarly, BC2059 induces apoptosis in primary multiple myeloma samples in vitro, causing minimal apoptosis on healthy peripheral blood mononuclear cells. Furthermore, it synergizes with the proteasome inhibitor bortezomib both in HMCL and primary multiple myeloma samples. Finally, in xenograft models of human myelomatosis, BC2059 delays tumor growth and prolongs survival with minor on-target side effects. Collectively, these results demonstrate the efficacy of targeting the Wnt/ß-catenin pathway with BC2059 both in vitro and in vivo, at clinically achievable doses. These findings support further clinical evaluation of BC2059 for the treatment of multiple myeloma. Mol Cancer Ther; 16(9); 1765-78. ©2017 AACR.


Assuntos
Antineoplásicos/farmacologia , Bortezomib/farmacologia , Mieloma Múltiplo/metabolismo , Inibidores de Proteassoma/farmacologia , beta Catenina/metabolismo , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Camundongos Transgênicos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Ativação Transcricional/efeitos dos fármacos , Carga Tumoral , beta Catenina/antagonistas & inibidores , beta Catenina/genética
13.
Artigo em Inglês | MEDLINE | ID: mdl-11853112

RESUMO

Gabapentin is an anticonvulsant agent, also effective in the treatment of mood disorders and anxiety disorders. Three cases of alcohol withdrawal treated with gabapentin are presented. All patients received gabapentin 400 mg tid for 3 days, 400 mg bid for 1 day, and finally 400 mg for 1 day. Withdrawal symptoms subsided and no adverse effects were observed. The possible effectiveness of gabapentin in the treatment of alcohol withdrawal warrants further investigation by systematic and well-designed studies.


Assuntos
Acetatos/uso terapêutico , Aminas , Ansiolíticos/uso terapêutico , Ácidos Cicloexanocarboxílicos , Etanol/efeitos adversos , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Ácido gama-Aminobutírico , Adulto , Gabapentina , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos do Humor/tratamento farmacológico , Transtornos do Humor/etiologia
14.
Int J Psychiatry Med ; 32(2): 201-8, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12269599

RESUMO

The diagnosis of factitious disorder by proxy is still under investigation. Few studies have researched the psychological status and potential underlying psychopathology of the perpetrator, as well as the impact on the child's development and the pathological reactions of rearing a child within the context of a distorted reality. In this article, we present the case of a 12-year-old boy where this diagnosis was suspected. Both he and his parents brought forth false allegations of repeated physical abuse induced by his schoolteacher. The parents presented with shared psychosis and the child presented with conduct disorder, factitious disorder, and emotional problems. We suggest that this case represents a Münchausen by proxy-like syndrome involving both the legal and medical systems. Hypotheses regarding the pathogenesis of symptoms in the child are noted, underscoring the differences between Münchausen by proxy syndrome appearing in infancy with that appearing in older children.


Assuntos
Transtornos Autoinduzidos/psicologia , Síndrome de Munchausen Causada por Terceiro/diagnóstico , Criança , Transtorno da Conduta/diagnóstico , Docentes , Humanos , Masculino , Pais , Instituições Acadêmicas
15.
Fam Process ; 42(3): 391-402, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14606202

RESUMO

The diagnosis of "mental illness" is accompanied by negative implications regarding a person's competence. Self- and other-descriptions about the "patient" are embedded within broader cultural and societal discourses, influencing his/her relationships. The parental role seems to be one of the most sensitive, especially for women. Mothers hospitalized in psychiatric units often have to separate themselves from their children either temporarily, during hospitalization, or permanently, after a loss of custody. However, many studies have shown that mothering remains important for them. We interviewed 20 women, inpatients on a psychiatric unit and mothers of 3.5-18-year-old children, recording their narratives about their children and exploring their thoughts and understanding of the concepts of motherhood and mental illness. We also explored the way in which the mother-child dyad interacted with the family and its social context. Most mothers had a consistent and coherent narrative about their children and they had certain expectations of them. The mother-child bond was strong, even when the children had been removed from their mothers' custody. However, mothers were facing great difficulties with their partner and with the broader family context. Also, the social discourses regarding mental illness, (e.g., violence and incapability for mothering), were extremely oppressive for these women. They felt that they were the victims of societal attitudes even before they became pregnant. These findings suggest the importance of listening to the voices of these women; acknowledging their competence in the therapeutic context; involving them with their families, and in legal and social contexts; and in planning supportive programs for them.


Assuntos
Bem-Estar Materno , Transtornos Mentais/reabilitação , Mães/psicologia , Narração , Adulto , Criança , Cultura , Feminino , Hospitalização , Humanos , Relações Interpessoais , Relações Mãe-Filho , Unidade Hospitalar de Psiquiatria , Estereotipagem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA