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Nat Med ; 25(3): 454-461, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30804515


Immunologic responses to anti-PD-1 therapy in melanoma patients occur rapidly with pharmacodynamic T cell responses detectable in blood by 3 weeks. It is unclear, however, whether these early blood-based observations translate to the tumor microenvironment. We conducted a study of neoadjuvant/adjuvant anti-PD-1 therapy in stage III/IV melanoma. We hypothesized that immune reinvigoration in the tumor would be detectable at 3 weeks and that this response would correlate with disease-free survival. We identified a rapid and potent anti-tumor response, with 8 of 27 patients experiencing a complete or major pathological response after a single dose of anti-PD-1, all of whom remain disease free. These rapid pathologic and clinical responses were associated with accumulation of exhausted CD8 T cells in the tumor at 3 weeks, with reinvigoration in the blood observed as early as 1 week. Transcriptional analysis demonstrated a pretreatment immune signature (neoadjuvant response signature) that was associated with clinical benefit. In contrast, patients with disease recurrence displayed mechanisms of resistance including immune suppression, mutational escape, and/or tumor evolution. Neoadjuvant anti-PD-1 treatment is effective in high-risk resectable stage III/IV melanoma. Pathological response and immunological analyses after a single neoadjuvant dose can be used to predict clinical outcome and to dissect underlying mechanisms in checkpoint blockade.

Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Procedimentos Cirúrgicos Dermatológicos , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos T CD8-Positivos , Quimioterapia Adjuvante , Feminino , Perfilação da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Neoplasias Cutâneas/patologia , Transcriptoma , Evasão Tumoral
Nature ; 545(7652): 60-65, 2017 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-28397821


Despite the success of monotherapies based on blockade of programmed cell death 1 (PD-1) in human melanoma, most patients do not experience durable clinical benefit. Pre-existing T-cell infiltration and/or the presence of PD-L1 in tumours may be used as indicators of clinical response; however, blood-based profiling to understand the mechanisms of PD-1 blockade has not been widely explored. Here we use immune profiling of peripheral blood from patients with stage IV melanoma before and after treatment with the PD-1-targeting antibody pembrolizumab and identify pharmacodynamic changes in circulating exhausted-phenotype CD8 T cells (Tex cells). Most of the patients demonstrated an immunological response to pembrolizumab. Clinical failure in many patients was not solely due to an inability to induce immune reinvigoration, but rather resulted from an imbalance between T-cell reinvigoration and tumour burden. The magnitude of reinvigoration of circulating Tex cells determined in relation to pretreatment tumour burden correlated with clinical response. By focused profiling of a mechanistically relevant circulating T-cell subpopulation calibrated to pretreatment disease burden, we identify a clinically accessible potential on-treatment predictor of response to PD-1 blockade.

Linfócitos T CD8-Positivos/imunologia , Melanoma/tratamento farmacológico , Melanoma/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Carga Tumoral/imunologia , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/imunologia , Anticorpos Monoclonais Humanizados/farmacocinética , Anticorpos Monoclonais Humanizados/uso terapêutico , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/metabolismo , Feminino , Humanos , Antígeno Ki-67/imunologia , Antígeno Ki-67/metabolismo , Masculino , Melanoma/irrigação sanguínea , Melanoma/patologia , Estadiamento de Neoplasias , Fenótipo , Resultado do Tratamento
Br J Haematol ; 177(1): 13-26, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27977050


The success of genetically engineered T cells that express chimeric antigen receptors (CARTs) has been a momentous step forward in harnessing the potent cancer fighting abilities of the immune system. The efficacy seen in relapsed/refractory (r/r) acute lymphoblastic leukaemia (ALL), not only by inducing remission, but also in maintaining long-term disease control, has been unprecedented. While the foundation for this approach has been firmly set in place, continued development will improve the efficacy, toxicity and applicability to other malignancies of this new class of 'living drugs'. In this review, we provide a comprehensive overview of the most current clinical trial data in both acute and chronic leukaemias, and discuss some of the potential ways to enhance the activity and safety of CART therapy going forward.

Terapia Genética , Imunoterapia Adotiva , Leucemia/imunologia , Leucemia/terapia , Receptores de Antígenos de Linfócitos T/metabolismo , Proteínas Recombinantes de Fusão , Animais , Antígenos CD19/imunologia , Antígenos CD19/metabolismo , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/metabolismo , Ensaios Clínicos como Assunto , Terapia Genética/efeitos adversos , Terapia Genética/métodos , Humanos , Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/métodos , Receptores de Antígenos de Linfócitos T/genética , Resultado do Tratamento
Curr Opin Hematol ; 22(2): 97-107, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25575037


PURPOSE OF REVIEW: Despite successful remission induction in 60-80% of patients with newly diagnosed acute myeloid leukemia, there remain a significant number of patients who exhibit primary refractory disease. Here we examine the data for predicting likelihood of having refractory disease, available therapeutic options, and how to decide the appropriate treatment option for a patient. RECENT FINDINGS: Recently identified recurrent molecular mutations and early response to chemotherapy as determined by kinetics of peripheral blast clearance or nadir bone marrow biopsy assist in determining the likelihood of primary refractory disease. Newer cytotoxic agents, used as salvage chemotherapy, or in novel conditioning regimens for hematopoietic stem cell transplant may represent improvement over prior regimens. FMS-like tyrosine kinase 3 gene inhibitors and other targeted therapies currently in clinical trials show promise for select patients. Hypomethylating agents provide benefit to patients who are not candidates for other therapies. SUMMARY: Recent advances in understanding the pathogenesis of acute myeloid leukemia have not yet translated to a significantly improved outlook for patients with refractory disease. While there are several therapeutic options, outcomes remain poor and further studies are needed to identify and validate novel approaches.

Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda/terapia , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/etiologia , Leucemia Mieloide Aguda/mortalidade , Prognóstico , Indução de Remissão , Terapia de Salvação , Resultado do Tratamento
Immunology ; 125(3): 408-19, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18462347


The aetiopathogenesis of the abnormal immune response in systemic lupus erythematosus (SLE) remains incompletely understood. We and other investigators demonstrated altered expression of adenosine deaminase that act on RNA (ADAR) genes in SLE patients. Based on this information, we hypothesize that the altered expression and function of ADAR enzymes is a mechanism for the immunopathogenesis of SLE. ADARs edit gene transcripts through site-specific conversion of adenosine to inosine by hydrolytic deamination at C6 of the adenosine. Thirteen SLE subjects and eight healthy controls were studied. We assessed the role of ADAR enzymes in editing of PDE8A1 gene transcripts of normal and SLE T cells. These studies demonstrated the occurrence of ADAR-catalysed altered and site-selective editing profile of specific sites in the PDE8A1 gene transcripts of normal and SLE T cells. Two hot spots for A to I editing were observed in the PDE8A1 transcripts of normal and SLE T cells. A fundamental finding of this study is A to I hypo-editing followed by up-regulation of PDE8A1 transcripts in SLE T cells. These results are confirmed by analysing PDE8A1 transcripts of normal T cells activated with type I interferon-alpha. It is proposed that, the altered expression of ADAR enzymes tilt the balance of editing machinery and alter editing in SLE transcriptome. Such altered editing may contribute to the modulation of gene regulation and ultimately, immune functions in SLE and play an important role in the initiation and propagation of SLE pathogenesis.

3',5'-AMP Cíclico Fosfodiesterases/genética , Lúpus Eritematoso Sistêmico/imunologia , Linfócitos T/imunologia , 3',5'-AMP Cíclico Fosfodiesterases/imunologia , Adulto , Sequência de Bases , Células Cultivadas , Feminino , Humanos , Imunofenotipagem , Interferon-alfa/imunologia , Lúpus Eritematoso Sistêmico/genética , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Nucleotídeo Único , Edição de RNA , RNA Mensageiro/genética , Transcrição Genética , Regulação para Cima/imunologia