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1.
Front Immunol ; 10: 2455, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31681329

RESUMO

B-cell receptor (BCR)-dependent signaling is central for leukemia B-cell homeostasis, as underscored by the promising clinical results obtained in patients with chronic lymphocytic leukemia (CLL) treated with novel agents targeting components of this pathway. Herein, we demonstrate that the mithralog EC-7072 displays high ex vivo cytotoxic activity against leukemia cells from CLL patients independently from high-risk prognostic markers and IGHV mutational status. EC-7072 was significantly less toxic against T cells and NK cells and did not alter the production of the immune effector molecules IFN-γ and perforin. EC-7072 directly triggered caspase-3-dependent CLL cell apoptosis, which was not abrogated by microenvironment-derived factors that sustain leukemia cell survival. RNA-sequencing analyses revealed a dramatic EC-7072-driven reprograming of the transcriptome of CLL cells, including a wide downregulation of multiple components and targets of the BCR signaling pathway. Accordingly, we found decreased levels of phosphorylated signaling nodes downstream of the BCR. Crosslinking-mediated BCR activation antagonized CLL cell death triggered by EC-7072, increased the phosphorylation levels of the abovementioned signaling nodes and upregulated BCL2 expression, suggesting that the mithralog disrupts CLL cell viability by targeting the BCR signaling axis at multiple levels. EC-7072 exerted similar or higher antileukemic activity than that of several available CLL therapies and displayed additive or synergistic interaction with these drugs in killing CLL cells. Overall, our findings provide rationale for future investigation to test whether EC-7072 may be a potential therapeutic option for patients with CLL and other B-cell malignancies.

2.
Haematologica ; 104(3): 576-586, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30262568

RESUMO

Mutations in genes of the RAS-BRAF-MAPK-ERK pathway have not been fully explored in patients with chronic lymphocytic leukemia. We, therefore, analyzed the clinical and biological characteristics of chronic lymphocytic leukemia patients with mutations in this pathway and investigated the in vitro response of primary cells to BRAF and ERK inhibitors. Putative damaging mutations were found in 25 of 452 patients (5.5%). Among these, BRAF was mutated in nine patients (2.0%), genes upstream of BRAF (KITLG, KIT, PTPN11, GNB1, KRAS and NRAS) were mutated in 12 patients (2.6%), and genes downstream of BRAF (MAPK2K1, MAPK2K2, and MAPK1) were mutated in five patients (1.1%). The most frequent mutations were missense, subclonal and mutually exclusive. Patients with these mutations more frequently had increased lactate dehydrogenase levels, high expression of ZAP-70, CD49d, CD38, trisomy 12 and unmutated immunoglobulin heavy-chain variable region genes and had a worse 5-year time to first treatment (hazard ratio 1.8, P=0.025). Gene expression analysis showed upregulation of genes of the MAPK pathway in the group carrying RAS-BRAF-MAPK-ERK pathway mutations. The BRAF inhibitors vemurafenib and dabrafenib were not able to inhibit phosphorylation of ERK, the downstream effector of the pathway, in primary cells. In contrast, ulixertinib, a pan-ERK inhibitor, decreased phospho-ERK levels. In conclusion, although larger series of patients are needed to corroborate these findings, our results suggest that the RAS-BRAF-MAPK-ERK pathway is one of the core cellular processes affected by novel mutations in chronic lymphocytic leukemia, is associated with adverse clinical features and could be pharmacologically inhibited.

3.
Leuk Lymphoma ; 59(10): 2318-2326, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29115891

RESUMO

Small lymphocytic lymphoma (SLL) is considered as the non-leukemic form of presentation of chronic lymphocytic leukemia (CLL). We have compared the features, genomic alterations, and outcome of 890 patients with CLL and SLL. One hundred and thirteen patients presented as SLL and more frequently had unmutated-IGHV, CD38high, ZAP-70high, CD49dhigh, +12, alterations in genes of NOTCH1, cell cycle, RNA metabolism, and NFkB pathways than CLL. During the follow-up, 46% of SLL patients developed CLL. Time to first treatment (TTFT) was shorter in SLL (10-year: 75% vs 62%; p = .006). Binet stage, SLL, and IGHV were independent predictive factors for TTFT. Transformation to diffuse large B-cell lymphoma was higher (10-year: 12% vs 6%; p = .003), and overall survival was shorter in SLL (10-year: 55% vs 66%; p = .004). When A0 CLL patients were excluded, only CD38 and CD49d expression, +12, and 10-year TTFT remained different between the SLL and CLL patients. In summary, SLL showed only minor clinicobiological differences when compared with CLL in similar clinical stages.


Assuntos
Genoma Humano/genética , Leucemia Linfocítica Crônica de Células B/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise Mutacional de DNA , Feminino , Seguimentos , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/mortalidade , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Análise de Sobrevida , Tempo para o Tratamento/estatística & dados numéricos , Adulto Jovem
4.
Front Immunol ; 9: 2917, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30619281

RESUMO

One of the cardinal features of chronic lymphocytic leukemia (CLL) is its association with a profound immunosuppression. NK cell function is markedly impaired in CLL patients, who show a significant dysregulation of the expression of activating and inhibitory receptors. Here, we analyzed the role of the novel inhibitory receptor Ig-like transcript 2 (ILT2, also termed LIR-1, LILRB1) in the regulation of NK cells in CLL. Our results show that ILT2 expression was significantly decreased on leukemic cells and increased on NK cells of CLL patients, particularly in those with advanced disease and with bad prognostic features, such as those carrying chromosome del(11q). The immunomodulatory drug lenalidomide may regulate the expression of ILT2 and its ligands in CLL since it significantly increased the expression of ILT2 and partially reestablished the expression of its ligands on leukemic cells. Furthermore, lenalidomide significantly increased the activation and proliferation of NK cells, which was strongly enhanced by ILT2 blockade. Combining ILT2 blockade and lenalidomide activated NK cell cytotoxicity resulting in increased elimination of leukemic cells from CLL patients. Overall, we describe herein the role of an inhibitory receptor involved in the suppression of NK cell activity in CLL, which is restored by ILT2 blockade in combination with lenalidomide, suggesting that it may be an interesting therapeutic strategy to be explored in this disease.


Assuntos
Anticorpos Bloqueadores/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Células Matadoras Naturais/efeitos dos fármacos , Lenalidomida/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Receptor B1 de Leucócitos Semelhante a Imunoglobulina/antagonistas & inibidores , Idoso , Anticorpos Bloqueadores/administração & dosagem , Anticorpos Bloqueadores/imunologia , Antígenos CD/imunologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Deleção Cromossômica , Sinergismo Farmacológico , Feminino , Humanos , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/uso terapêutico , Células Matadoras Naturais/imunologia , Lenalidomida/administração & dosagem , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/imunologia , Receptor B1 de Leucócitos Semelhante a Imunoglobulina/imunologia , Masculino , Pessoa de Meia-Idade
5.
Oncoimmunology ; 6(10): e1353856, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29123965

RESUMO

Chronic lymphocytic leukemia (CLL) is associated with a profound dysregulation of the immune system. Loss of T cell function is frequently caused in cancer by sustained signaling of inhibitory receptors. Here, we analyzed the role of the novel inhibitory receptor Ig-like transcript 2 (ILT2) in the pathogenesis of CLL. We observed that ILT2 expression was markedly reduced on leukemic cells, whereas it was increased on CD8 and CD4 T cells from CLL patients, particularly in those patients harboring chromosome 11q deletion, which includes the ATM gene. A deep dysregulation of ILT2 ligands expression in leukemia cells was also observed. ILT2 impaired the activation and proliferation of CD4 and CD8 T cells in CLL patients, but it had no effect in leukemic cells. ILT2 downregulated the production of IL-2 by CD4 T cells of CLL patients and induced the expression of cytokines that promote the survival of leukemic cells, such as IFN-γ, by T cells. Importantly, ILT2 blockade restored the activation, proliferation and cytokine production of T cells. In conclusion, we describe a novel immune inhibitory pathway that is upregulated in CLL and delineate a new potential target to be explored in this disease.

6.
Nature ; 526(7574): 519-24, 2015 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-26200345

RESUMO

Chronic lymphocytic leukaemia (CLL) is a frequent disease in which the genetic alterations determining the clinicobiological behaviour are not fully understood. Here we describe a comprehensive evaluation of the genomic landscape of 452 CLL cases and 54 patients with monoclonal B-lymphocytosis, a precursor disorder. We extend the number of CLL driver alterations, including changes in ZNF292, ZMYM3, ARID1A and PTPN11. We also identify novel recurrent mutations in non-coding regions, including the 3' region of NOTCH1, which cause aberrant splicing events, increase NOTCH1 activity and result in a more aggressive disease. In addition, mutations in an enhancer located on chromosome 9p13 result in reduced expression of the B-cell-specific transcription factor PAX5. The accumulative number of driver alterations (0 to ≥4) discriminated between patients with differences in clinical behaviour. This study provides an integrated portrait of the CLL genomic landscape, identifies new recurrent driver mutations of the disease, and suggests clinical interventions that may improve the management of this neoplasia.


Assuntos
Leucemia Linfocítica Crônica de Células B/genética , Mutação/genética , Regiões 3' não Traduzidas/genética , Processamento Alternativo/genética , Linfócitos B/metabolismo , Proteínas de Transporte/genética , Cromossomos Humanos Par 9/genética , Análise Mutacional de DNA , DNA de Neoplasias/genética , Elementos Facilitadores Genéticos/genética , Genômica , Humanos , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética , Fator de Transcrição PAX5/biossíntese , Fator de Transcrição PAX5/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Receptor Notch1/genética , Receptor Notch1/metabolismo , Fatores de Transcrição/genética
7.
Haematologica ; 100(9): 1207-13, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26069291

RESUMO

This study analyzed the anti-myeloma effect of zoledronic acid monotherapy by investigating patients at the time of asymptomatic biochemical relapse. One hundred patients were randomized to receive either zoledronic acid (4 mg iv/4 weeks, 12 doses) (n=51) or not (n=49). Experimental and control groups were well balanced for disease and prognostic features. Zoledronic acid did not show an antitumor effect according to changes in M-component. However, there were fewer symptomatic progressions in the experimental group than in the control group (34 versus 41, respectively; P=0.05) resulting in a median time to symptoms of 16 versus 10 months (P=0.161). The median time to next therapy was also slightly longer for the treated group than the untreated, control group (13.4 versus 10.1 months), although the difference was not statistically significant (P=0.360). The pattern of relapses was different for treated versus control patients: progressive bone disease (8 versus 20), anemia (24 versus 18), renal dysfunction (1 versus 2), and plasmacytomas (1 versus 1, respectively). This concurred with fewer skeletal-related events in the treated group than in the control group (2 versus 14), with a projected 4-year event proportion of 6% versus 40% (P<0.001). In summary, zoledronic acid monotherapy does not show an antitumor effect on biochemical relapses in multiple myeloma, but does reduce the risk of progression with symptomatic bone disease and skeletal complications. This trial was registered in the ClinicalTrials.gov database with code NCT01087008.


Assuntos
Doenças Ósseas/tratamento farmacológico , Doenças Ósseas/mortalidade , Difosfonatos/administração & dosagem , Imidazóis/administração & dosagem , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/mortalidade , Adulto , Idoso , Doenças Ósseas/patologia , Intervalo Livre de Doença , Humanos , Pessoa de Meia-Idade , Mieloma Múltiplo/patologia , Taxa de Sobrevida , Ácido Zoledrônico
8.
PLoS One ; 9(10): e108326, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25286418

RESUMO

The immune system may mediate anti-tumor responses in chronic lymphocytic leukemia (CLL) which may affect disease progression and survival. In this study, we analyzed the immune characteristics of 99 consecutive previously diagnosed CLL patients and 50 healthy controls. The distribution of lymphocyte subsets at diagnosis was retrospectively analyzed. Compared with controls, leukemia patients showed an expansion of NK and CD8 T cells at diagnosis. The relative number of CD8 T cells at diagnosis was associated with time to treatment, suggesting that CD8 T cells may modify disease progression. The distribution of lymphocyte subsets was analyzed again when patients were enrolled in this study. The median time since these patients were diagnosed was 277 weeks. Compared with diagnosis, the absolute number of CD8 T cells significantly decreased in these patients, reaching similar values to healthy controls; however NK cells kept significantly elevated overtime. Nevertheless, NK cells showed an impaired expression of NKG2D receptor and a defective cytotoxic activity. This down-regulation of NKG2D expression was further enhanced in patients with advanced and progressive disease. Additionally, membrane NKG2D levels significantly decreased on CD8 T cells, but a significant increase of NKG2D+CD4+ T cells was observed in CLL patients. The cytotoxic activity of NK cells was diminished in CLL patients; however the treatments with IL-2, IL-15, IL-21 and lenalidomide were able to restore their activity. The effect of IL-2 and IL-15 was associated with the increase of NKG2D expression on immune cells, but the effect of IL-21 and lenalidomide was not due to NKG2D up-regulation. The expansion of NK cells and the reversibility of NK cell defects provide new opportunities for the immunotherapeutic intervention in CLL.


Assuntos
Progressão da Doença , Células Matadoras Naturais/imunologia , Leucemia Linfocítica Crônica de Células B/imunologia , Leucemia Linfocítica Crônica de Células B/patologia , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Idoso , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Citotoxicidade Imunológica/efeitos dos fármacos , Feminino , Humanos , Fatores Imunológicos/farmacologia , Células K562 , Células Matadoras Naturais/efeitos dos fármacos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Contagem de Linfócitos , Masculino , Prognóstico
9.
Biomed Res Int ; 2014: 265840, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25313353

RESUMO

Lenalidomide is an immunomodulatory drug with therapeutic activity in chronic lymphocytic leukemia (CLL). However, it has pleiotropic effects, and the mechanism of action responsible for its therapeutic activity has not been well defined yet. Herein, we show that lenalidomide treatment does not have an effect on the proliferation of leukemia cells, but it increases the proliferation of B cells from healthy donors. Lenalidomide did not exert a direct effect on the apoptosis of leukemia cells obtained from CLL patients, although it indirectly induced their apoptosis through the activation of nonmalignant immune cells. Thus, lenalidomide markedly increased the proliferation of NK and CD4 T cells. The effect of lenalidomide on NK cells was secondary to the induction of IL-2 production by CD4 T cells. Accordingly, depletion of T cells or blockade of IL-2 activity completely abrogated the proliferation of NK cells. Additionally, lenalidomide enhanced NK and NKT-like cell-mediated natural cytotoxicity against leukemia cells from CLL patients. Lenalidomide also upregulated CD20 expression on leukemia cells and, accordingly, it had a synergistic effect with rituximab on promoting antibody-dependent cell-mediated cytotoxicity against primary leukemia cells. Overall, these observations provide a support for combining lenalidomide with rituximab as a treatment in CLL.


Assuntos
Antineoplásicos/uso terapêutico , Linfócitos T CD4-Positivos/imunologia , Imunomodulação/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/imunologia , Talidomida/análogos & derivados , Citotoxicidade Celular Dependente de Anticorpos/efeitos dos fármacos , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Interleucina-2/biossíntese , Células Matadoras Naturais/efeitos dos fármacos , Lenalidomida , Leucemia Linfocítica Crônica de Células B/patologia , Subpopulações de Linfócitos/efeitos dos fármacos , Talidomida/farmacologia , Talidomida/uso terapêutico , Células Tumorais Cultivadas
11.
Blood ; 123(24): 3790-6, 2014 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-24782504

RESUMO

Mutations in Toll-like receptor (TLR) and myeloid differentiation primary response 88 (MYD88) genes have been found in chronic lymphocytic leukemia (CLL) at low frequency. We analyzed the incidence, clinicobiological characteristics, and outcome of patients with TLR/MYD88 mutations in 587 CLL patients. Twenty-three patients (3.9%) had mutations, 19 in MYD88 (one with concurrent IRAK1 mutation), 2 TLR2 (one with concomitant TLR6 mutation), 1 IRAK1, and 1 TLR5. No mutations were found in IRAK2 and IRAK4. TLR/MYD88-mutated CLL overexpressed genes of the nuclear factor κB pathway. Patients with TLR/MYD88 mutations were significantly younger (83% age ≤50 years) than those with no mutations. TLR/MYD88 mutations were the most frequent in young patients. Patients with mutated TLR/MYD88 CLL had a higher frequency of mutated IGHV and low expression of CD38 and ZAP-70. Overall survival (OS) was better in TLR/MYD88-mutated than unmutated patients in the whole series (10-year OS, 100% vs 62%; P = .002), and in the subset of patients age ≤50 years (100% vs 70%; P = .02). In addition, relative OS of TLR/MYD88-mutated patients was similar to that in the age- and gender-matched population. In summary, TLR/MYD88 mutations identify a population of young CLL patients with favorable outcome.


Assuntos
Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/genética , Mutação , Fator 88 de Diferenciação Mieloide/genética , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Transdução de Sinais/genética , Adulto Jovem
12.
Biomed Res Int ; 2013: 932010, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24163824

RESUMO

Lenalidomide is an oral immunomodulatory drug used in multiple myeloma and myelodysplastic syndrome and most recently it has shown to be effective in the treatment of various lymphoproliferative disorders such as chronic lymphocytic leukemia (CLL) and non-Hodgkin lymphoma. The mechanism of action of lenalidomide varies depending on the pathology, and in the case of CLL, it appears to primarily act by restoring the damaged mechanisms of tumour immunosurveillance. This review discusses the potential mechanism of action and efficacy of lenalidomide, alone or in combination, in treatment of CLL and its toxic effects such as tumor lysis syndrome (TLS) and tumor flare reaction (TFR), that make its management different from other hematologic malignancies.


Assuntos
Fatores Imunológicos/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Talidomida/análogos & derivados , Anticorpos Monoclonais Murinos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Ensaios Clínicos como Assunto , Humanos , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/efeitos adversos , Imunomodulação , Lenalidomida , Leucemia Linfocítica Crônica de Células B/imunologia , Leucemia Linfocítica Crônica de Células B/terapia , Rituximab , Talidomida/administração & dosagem , Talidomida/efeitos adversos , Talidomida/uso terapêutico
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