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1.
Nat Med ; 25(12): 1839-1842, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31768065

RESUMO

Histiocytoses are clonal hematopoietic disorders frequently driven by mutations mapping to the BRAF and MEK1 and MEK2 kinases. Currently, however, the developmental origins of histiocytoses in patients are not well understood, and clinically meaningful therapeutic targets outside of BRAF and MEK are undefined. In this study, we uncovered activating mutations in CSF1R and rearrangements in RET and ALK that conferred dramatic responses to selective inhibition of RET (selpercatinib) and crizotinib, respectively, in patients with histiocytosis.


Assuntos
Quinase do Linfoma Anaplásico/genética , Histiocitose/genética , Proteínas Proto-Oncogênicas c-ret/genética , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/genética , Adolescente , Adulto , Aminopiridinas/farmacologia , Benzotiazóis/farmacologia , Criança , Pré-Escolar , Feminino , Genoma Humano , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/patologia , Histiocitose/tratamento farmacológico , Histiocitose/patologia , Humanos , Lactente , Masculino , Mutação , Ácidos Picolínicos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Piridinas/farmacologia , Pirróis/farmacologia , Receptores Proteína Tirosina Quinases/genética , Gêmeos Monozigóticos , Sequenciamento Completo do Exoma , Adulto Jovem
2.
Nature ; 574(7778): 432-436, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31597964

RESUMO

SF3B1 is the most commonly mutated RNA splicing factor in cancer1-4, but the mechanisms by which SF3B1 mutations promote malignancy are poorly understood. Here we integrated pan-cancer splicing analyses with a positive-enrichment CRISPR screen to prioritize splicing alterations that promote tumorigenesis. We report that diverse SF3B1 mutations converge on repression of BRD9, which is a core component of the recently described non-canonical BAF chromatin-remodelling complex that also contains GLTSCR1 and GLTSCR1L5-7. Mutant SF3B1 recognizes an aberrant, deep intronic branchpoint within BRD9 and thereby induces the inclusion of a poison exon that is derived from an endogenous retroviral element and subsequent degradation of BRD9 mRNA. Depletion of BRD9 causes the loss of non-canonical BAF at CTCF-associated loci and promotes melanomagenesis. BRD9 is a potent tumour suppressor in uveal melanoma, such that correcting mis-splicing of BRD9 in SF3B1-mutant cells using antisense oligonucleotides or CRISPR-directed mutagenesis suppresses tumour growth. Our results implicate the disruption of non-canonical BAF in the diverse cancer types that carry SF3B1 mutations and suggest a mechanism-based therapeutic approach for treating these malignancies.

3.
JAMA Oncol ; 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31318385

RESUMO

Importance: Multiple myeloma is consistently preceded by monoclonal gammopathy of undetermined significance (MGUS). Risk models that estimate the risk of progression from MGUS to multiple myeloma use data from a single time point, usually the initial workup. Objective: To longitudinally investigate the alterations of serum immune markers with stable vs progressive MGUS. Design, Setting, and Participants: This prospective cross-sectional cohort study included 77 469 adult participants aged 55 to 74 years in the screening arm of the National Cancer Institute Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial who had a diagnosis of progressing MGUS (n = 187) or stable MGUS (n = 498), including light-chain subtype, from November 1993, through December 2011. For each participant, all available serially stored prediagnostic serum samples (N = 3266) were obtained. Data analysis was performed from April 2018, to December 2018. Main Outcomes and Measures: Serum protein and monoclonal immunoglobulin levels, serum free light chains, and serum light chains within each immunoglobulin class were measured. Results: Of 685 individuals included in the study, 461 (67.3%) were men; the mean (SD) age was 69.1 (5.6) years. In cross-sectional modeling, risk factors associated with progressive MGUS were IgA isotype (adjusted odds ratio [OR], 1.80; 95% CI, 1.03-3.13; P = .04), 15 g/L or more monoclonal spike (adjusted OR, 23.5; 95% CI, 8.9-61.9; P < .001), skewed (<0.1 or >10) serum free light chains ratio (adjusted OR, 46.4; 95% CI, 18.4-117.0; P < .001), and severe immunoparesis (≥2 suppressed uninvolved immunoglobulins) (adjusted OR, 19.1; 95% Cl, 7.5-48.3; P < .001). Risk factors associated with progressive light-chain MGUS were skewed serum free light chains ratio (adjusted OR, 44.0; 95% CI, 14.2-136.3; P < .001) and severe immunoparesis (adjusted OR, 48.6; 95% CI, 9.5-248.2; P < .001). In longitudinal analysis of participants with serial samples prior to progression, 23 of 43 participants (53%) had high-risk MGUS before progression; 16 of these 23 (70%) experienced conversion from low-risk or intermediate-risk MGUS within 5 years. Similar results were found for light-chain MGUS. Conclusions and Relevance: The findings of evolving risk patterns support annual blood testing and risk assessment for patients with MGUS or light-chain MGUS.

4.
Nat Commun ; 10(1): 1874, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31015400

RESUMO

Cancer evolution is fueled by epigenetic as well as genetic diversity. In chronic lymphocytic leukemia (CLL), intra-tumoral DNA methylation (DNAme) heterogeneity empowers evolution. Here, to comprehensively study the epigenetic dimension of cancer evolution, we integrate DNAme analysis with histone modification mapping and single cell analyses of RNA expression and DNAme in 22 primary CLL and 13 healthy donor B lymphocyte samples. Our data reveal corrupted coherence across different layers of the CLL epigenome. This manifests in decreased mutual information across epigenetic modifications and gene expression attributed to cell-to-cell heterogeneity. Disrupted epigenetic-transcriptional coordination in CLL is also reflected in the dysregulation of the transcriptional output as a function of the combinatorial chromatin states, including incomplete Polycomb-mediated gene silencing. Notably, we observe unexpected co-mapping of typically mutually exclusive activating and repressing histone modifications, suggestive of intra-tumoral epigenetic diversity. Thus, CLL epigenetic diversification leads to decreased coordination across layers of epigenetic information, likely reflecting an admixture of cells with diverging cellular identities.


Assuntos
Linfócitos B/metabolismo , Cromatina/metabolismo , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Leucemia Linfocítica Crônica de Células B/genética , Metilação de DNA , Evolução Molecular , Inativação Gênica , Genes de Cadeia Pesada de Imunoglobulina/genética , Voluntários Saudáveis , Código das Histonas/genética , Histonas/genética , Histonas/metabolismo , Humanos , Leucemia Linfocítica Crônica de Células B/sangue , Proteínas do Grupo Polycomb/genética , Proteínas do Grupo Polycomb/metabolismo , Regiões Promotoras Genéticas/genética , Análise de Sequência de RNA , Análise de Célula Única/métodos , Sequenciamento Completo do Exoma
5.
Cancer Cell ; 35(3): 369-384.e7, 2019 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-30799057

RESUMO

RNA-binding proteins (RBPs) are essential modulators of transcription and translation frequently dysregulated in cancer. We systematically interrogated RBP dependencies in human cancers using a comprehensive CRISPR/Cas9 domain-focused screen targeting RNA-binding domains of 490 classical RBPs. This uncovered a network of physically interacting RBPs upregulated in acute myeloid leukemia (AML) and crucial for maintaining RNA splicing and AML survival. Genetic or pharmacologic targeting of one key member of this network, RBM39, repressed cassette exon inclusion and promoted intron retention within mRNAs encoding HOXA9 targets as well as in other RBPs preferentially required in AML. The effects of RBM39 loss on splicing further resulted in preferential lethality of spliceosomal mutant AML, providing a strategy for treatment of AML bearing RBP splicing mutations.


Assuntos
Redes Reguladoras de Genes , Marcação de Genes/métodos , Leucemia Mieloide Aguda/patologia , Proteômica/métodos , Proteínas de Ligação a RNA/genética , Regulação para Cima , Processamento Alternativo , Animais , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Células HL-60 , Proteínas de Homeodomínio/genética , Humanos , Células Jurkat , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Masculino , Camundongos , Transplante de Neoplasias , Prognóstico , Proteínas de Ligação a RNA/metabolismo , Análise de Sequência de RNA/métodos , Análise de Sobrevida
6.
Cancer Cell ; 34(2): 225-241.e8, 2018 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-30107174

RESUMO

Mutations affecting RNA splicing factors are the most common genetic alterations in myelodysplastic syndrome (MDS) patients and occur in a mutually exclusive manner. The basis for the mutual exclusivity of these mutations and how they contribute to MDS is not well understood. Here we report that although different spliceosome gene mutations impart distinct effects on splicing, they are negatively selected for when co-expressed due to aberrant splicing and downregulation of regulators of hematopoietic stem cell survival and quiescence. In addition to this synthetic lethal interaction, mutations in the splicing factors SF3B1 and SRSF2 share convergent effects on aberrant splicing of mRNAs that promote nuclear factor κB signaling. These data identify shared consequences of splicing-factor mutations and the basis for their mutual exclusivity.


Assuntos
Mutação , Neoplasias/genética , Spliceossomos , Animais , Caspase 8/genética , Feminino , Hematopoese , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/fisiologia , Fosfoproteínas/genética , Fatores de Processamento de RNA/genética , Fatores de Processamento de Serina-Arginina/genética
7.
Semin Hematol ; 55(1): 44-50, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29759154

RESUMO

The past decade, several highly efficacious drugs have been approved for the treatment of multiple myeloma. Many of these newer drugs are less toxic than older chemotherapy drugs. Using modern combination therapy in newly diagnosed multiple myeloma patients, high proportions of newly diagnosed multiple myeloma patients obtain minimal residual disease (MRD) negativity and MRD testing has rapidly become an integral part of clinical trials focusing on patients in this setting. Only recently, MRD negativity was reported in clinical trials focusing on older newly diagnosed multiple myeloma patients (ie, nontransplant candidates), as well as studies focusing on patients with relapsed or refractory multiple myeloma. In the past, deeper responses were rarely seen in these patient categories due to inferior therapies and lack of MRD assays. The reason for the rapidly increased interest in MRD testing in all types of clinical trials is the fact that MRD negativity is closely correlated with longer progression-free survival which has been documented in recent meta-analyses. Consequently, MRD negativity has the potential to soon become a regulatory surrogate end-point for drug approval. This review dissects and discusses current data on MRD in multiple myeloma, it outlines new hypotheses, which can be tested in future clinical studies, and it discusses opportunities and future avenues for translational research. The goal of this article is to stimulate critical analysis of our current treatment landscape and development of future translational research involving MRD testing.


Assuntos
Mieloma Múltiplo/terapia , Neoplasia Residual/terapia , Humanos , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/patologia , Neoplasia Residual/diagnóstico , Neoplasia Residual/patologia
8.
Blood ; 130(14): 1644-1648, 2017 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-28801450

RESUMO

Classical hairy cell leukemia (cHCL) is characterized by a near 100% frequency of the BRAFV600E mutation, whereas ∼30% of variant HCLs (vHCLs) have MAP2K1 mutations. However, recurrent genetic alterations cooperating with BRAFV600E or MAP2K1 mutations in HCL, as well as those in MAP2K1 wild-type vHCL, are not well defined. We therefore performed deep targeted mutational and copy number analysis of cHCL (n = 53) and vHCL (n = 8). The most common genetic alteration in cHCL apart from BRAFV600E was heterozygous loss of chromosome 7q, the minimally deleted region of which targeted wild-type BRAF, subdividing cHCL into those hemizygous versus heterozygous for the BRAFV600E mutation. In addition to CDKN1B mutations in cHCL, recurrent inactivating mutations in KMT2C (MLL3) were identified in 15% and 25% of cHCLs and vHCLs, respectively. Moreover, 13% of vHCLs harbored predicted activating mutations in CCND3 A change-of-function mutation in the splicing factor U2AF1 was also present in 13% of vHCLs. Genomic analysis of de novo vemurafenib-resistant cHCL identified a novel gain-of-function mutation in IRS1 and losses of NF1 and NF2, each of which contributed to resistance. These data provide further insight into the genetic bases of cHCL and vHCL and mechanisms of RAF inhibitor resistance encountered clinically.


Assuntos
Leucemia de Células Pilosas/genética , Mutação , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Ciclina D3/genética , Inibidor de Quinase Dependente de Ciclina p27/genética , Proteínas de Ligação a DNA/genética , Resistencia a Medicamentos Antineoplásicos , Genômica , Humanos , Indóis/farmacologia , Indóis/uso terapêutico , Leucemia de Células Pilosas/tratamento farmacológico , MAP Quinase Quinase 1/genética , Proteínas Proto-Oncogênicas B-raf/genética , Fator de Processamento U2AF/genética , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Vemurafenib
9.
Blood ; 130(4): 397-407, 2017 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-28576879

RESUMO

Chronic myelomonocytic leukemia (CMML) and juvenile myelomonocytic leukemia (JMML) are myelodysplastic syndrome (MDS)/myeloproliferative neoplasm (MPN) overlap disorders characterized by monocytosis, myelodysplasia, and a characteristic hypersensitivity to granulocyte-macrophage colony-stimulating factor (GM-CSF). Currently, there are no available disease-modifying therapies for CMML, nor are there preclinical models that fully recapitulate the unique features of CMML. Through use of immunocompromised mice with transgenic expression of human GM-CSF, interleukin-3, and stem cell factor in a NOD/SCID-IL2Rγnull background (NSGS mice), we demonstrate remarkable engraftment of CMML and JMML providing the first examples of serially transplantable and genetically accurate models of CMML. Xenotransplantation of CD34+ cells (n = 8 patients) or unfractionated bone marrow (BM) or peripheral blood mononuclear cells (n = 10) resulted in robust engraftment of CMML in BM, spleen, liver, and lung of recipients (n = 82 total mice). Engrafted cells were myeloid-restricted and matched the immunophenotype, morphology, and genetic mutations of the corresponding patient. Similar levels of engraftment were seen upon serial transplantation of human CD34+ cells in secondary NSGS recipients (2/5 patients, 6/11 mice), demonstrating the durability of CMML grafts and functionally validating CD34+ cells as harboring the disease-initiating compartment in vivo. Successful engraftments of JMML primary samples were also achieved in all NSGS recipients (n = 4 patients, n = 12 mice). Engraftment of CMML and JMML resulted in overt phenotypic abnormalities and lethality in recipients, which facilitated evaluation of the JAK2/FLT3 inhibitor pacritinib in vivo. These data reveal that NSGS mice support the development of CMML and JMML disease-initiating and mature leukemic cells in vivo, allowing creation of genetically accurate preclinical models of these disorders.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielomonocítica Juvenil/tratamento farmacológico , Síndromes Mielodisplásicas/tratamento farmacológico , Pirimidinas/farmacologia , Animais , Feminino , Xenoenxertos , Humanos , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Leucemia Mielomonocítica Juvenil/genética , Leucemia Mielomonocítica Juvenil/metabolismo , Leucemia Mielomonocítica Juvenil/patologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/patologia , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Transplante de Neoplasias , Ensaios Antitumorais Modelo de Xenoenxerto , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/metabolismo
11.
PLoS One ; 6(7): e21611, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21760897

RESUMO

BACKGROUND: Allogeneic bone marrow transplantation (allo-BMT) is a potentially curative therapy for a variety of hematologic diseases, but benefits, including graft-versus-tumor (GVT) activity are limited by graft-versus-host-disease (GVHD). Carcinoembryonic antigen related cell adhesion molecule 1 (Ceacam1) is a transmembrane glycoprotein found on epithelium, T cells, and many tumors. It regulates a variety of physiologic and pathological processes such as tumor biology, leukocyte activation, and energy homeostasis. Previous studies suggest that Ceacam1 negatively regulates inflammation in inflammatory bowel disease models. METHODS: We studied Ceacam1 as a regulator of GVHD and GVT after allogeneic bone marrow transplantation (allo-BMT) in mouse models. In vivo, Ceacam1(-/-) T cells caused increased GVHD mortality and GVHD of the colon, and greater numbers of donor T cells were positive for activation markers (CD25(hi), CD62L(lo)). Additionally, Ceacam1(-/-) CD8 T cells had greater expression of the gut-trafficking integrin α(4)ß(7), though both CD4 and CD8 T cells were found increased numbers in the gut post-transplant. Ceacam1(-/-) recipients also experienced increased GVHD mortality and GVHD of the colon, and alloreactive T cells displayed increased activation. Additionally, Ceacam1(-/-) mice had increased mortality and decreased numbers of regenerating small intestinal crypts upon radiation exposure. Conversely, Ceacam1-overexpressing T cells caused attenuated target-organ and systemic GVHD, which correlated with decreased donor T cell numbers in target tissues, and mortality. Finally, graft-versus-tumor survival in a Ceacam1(+) lymphoma model was improved in animals receiving Ceacam1(-/-) vs. control T cells. CONCLUSIONS: We conclude that Ceacam1 regulates T cell activation, GVHD target organ damage, and numbers of donor T cells in lymphoid organs and GVHD target tissues. In recipients of allo-BMT, Ceacam1 may also regulate tissue radiosensitivity. Because of its expression on both the donor graft and host tissues, this suggests that targeting Ceacam1 may represent a potent strategy for the regulation of GVHD and GVT after allogeneic transplantation.


Assuntos
Transplante de Medula Óssea/imunologia , Antígeno Carcinoembrionário/metabolismo , Doença Enxerto-Hospedeiro/imunologia , Efeito Enxerto vs Tumor/imunologia , Animais , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos da radiação , Polaridade Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Citotoxicidade Imunológica/efeitos da radiação , Células Dendríticas/imunologia , Células Dendríticas/efeitos da radiação , Doença Enxerto-Hospedeiro/complicações , Doença Enxerto-Hospedeiro/mortalidade , Efeito Enxerto vs Tumor/efeitos da radiação , Humanos , Integrinas/metabolismo , Intestino Delgado/patologia , Intestino Delgado/efeitos da radiação , Ativação Linfocitária/imunologia , Ativação Linfocitária/efeitos da radiação , Contagem de Linfócitos , Tecido Linfoide/citologia , Tecido Linfoide/efeitos da radiação , Camundongos , Especificidade de Órgãos/imunologia , Especificidade de Órgãos/efeitos da radiação , Lesões Experimentais por Radiação/complicações , Lesões Experimentais por Radiação/metabolismo , Lesões Experimentais por Radiação/patologia , Radiação Ionizante , Transplante Homólogo
12.
J Immunol ; 185(3): 1912-9, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20622117

RESUMO

Alloreactive T cells are crucial for graft-versus-host disease (GVHD) pathophysiology, and modulating their trafficking patterns has been efficacious in ameliorating experimental disease. We report in this paper that P-selectin, a glycoprotein found on resting and inflamed endothelium, is important for donor alloreactive T cells trafficking into GVHD target organs, such as the intestines and skin. Compared with wild-type (WT) recipients of allogeneic bone marrow transplantation, P-selectin(-/-) recipients exhibit decreased GVHD mortality and decreased GVHD of the skin, liver, and small bowels. This was associated with diminished infiltration of alloactivated T cells into the Peyer's patches and small bowels, coupled with increased numbers of donor T cells in the spleen and secondary lymphoid organs (SLOs). Surprisingly, however, donor T cells deficient for P-selectin glycoprotein ligand 1, the most well described P-selectin ligand, mediated GVHD similar to WT T cells and accumulated in SLO and target organs in similar numbers as WT T cells. This suggests that P-selectin may be required for trafficking into inflamed tissues but not SLO and that donor T cells may use multiple P-selectin ligands apart from P-selectin glycoprotein ligand 1 to interact with P-selectin and traffic into inflamed tissues during GVHD. We conclude that targeting P-selectin may be a viable strategy for GVHD prophylaxis or treatment.


Assuntos
Transplante de Medula Óssea/imunologia , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/terapia , Selectina-P/genética , Animais , Modelos Animais de Doenças , Endotélio Vascular/imunologia , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Doença Enxerto-Hospedeiro/fisiopatologia , Mediadores da Inflamação/metabolismo , Mediadores da Inflamação/fisiologia , Ligantes , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Glicoproteínas de Membrana/deficiência , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Selectina-P/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/patologia , Subpopulações de Linfócitos T/transplante , Transplante Homólogo
13.
J Natl Cancer Inst ; 102(12): 894-908, 2010 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-20463307

RESUMO

BACKGROUND Blood vessels are formed either by sprouting of resident tissue endothelial cells (angiogenesis) or by recruitment of bone marrow (BM)-derived circulating endothelial progenitor cells (EPCs, vasculogenesis). Neovascularization has been implicated in tumor growth and inflammation, but its roles in graft-vs-host disease (GVHD) and in tumors after allogeneic BM transplantation (allo-BMT) were not known. METHODS We analyzed neovascularization, the contribution of endothelial cells and EPCs, and the ability of anti-vascular endothelial-cadherin antibody, E4G10, to inhibit neovascularization in mice with GVHD after allo-BMT using immunofluorescence microscopy and flow cytometry. We examined survival and clinical and histopathologic GVHD in mice (n = 10-25 per group) in which GVHD was treated with the E4G10 antibody using immunohistochemistry, flow cytometry, and cytokine immunoassay. We also assessed survival, the contribution of green fluorescent protein-marked EPCs to the tumor vasculature, and the ability of E4G10 to inhibit tumor growth in tumor-bearing mice (n = 20-33 per group) after allo-BMT using histopathology and bioluminescence imaging. All statistical tests were two-sided. RESULTS We found increased neovascularization mediated by vasculogenesis, as opposed to angiogenesis, in GVHD target tissues, such as liver and intestines. Administration of E4G10 inhibited neovascularization by donor BM-derived cells without affecting host vascularization, inhibited both GVHD and tumor growth, and increased survival (at 60 days post-BMT and tumor challenge with A20 lymphoma, the probability of survival was 0.29 for control antibody-treated allo-BMT recipients vs 0.7 for E4G10-treated allo-BMT recipients, 95% confidence interval = 0.180 to 0.640, P < .001). CONCLUSIONS Therapeutic targeting of neovascularization in allo-BMT recipients is a novel strategy to simultaneously ameliorate GVHD and inhibit posttransplant tumor growth, providing a new approach to improve the overall outcome of allogeneic hematopoietic stem cell transplantation.


Assuntos
Inibidores da Angiogênese/farmacologia , Anticorpos Monoclonais/farmacologia , Antígenos CD/imunologia , Caderinas/imunologia , Doença Enxerto-Hospedeiro/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Neoplasias/irrigação sanguínea , Neoplasias/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Animais , Transplante de Medula Óssea/efeitos adversos , Feminino , Citometria de Fluxo , Imunofluorescência , Doença Enxerto-Hospedeiro/prevenção & controle , Camundongos , Camundongos Endogâmicos C57BL , Transplante Homólogo
14.
Biol Blood Marrow Transplant ; 16(1 Suppl): S138-45, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19857588

RESUMO

Disease relapse remains a major cause of mortality following allogeneic hematopoietic cell transplantation (HCT). Over the past decade, our understanding of the biology underlying the graft-versus-tumor/leukemia (GVT) effect has increased greatly; however, several other factors affect the occurrence and outcome of relapse, including conditioning regimen, type of allograft, and the histology, status, and sensitivity to chemotherapy of the disease being treated. The mainstay of relapse treatment is donor lymphocyte infusion (DLI), but the efficacy of DLI is quite variable depending on disease histology and state. As such, there is a significant need for novel therapies and strategies for relapse following allogeneic HCT, particularly in patients for whom DLI is not an option. The National Cancer Institute is sponsoring an international workshop to address issues and research questions relative to the biology, natural history, prevention, and treatment of relapse following allogeneic HCT.


Assuntos
Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/métodos , Animais , Efeito Enxerto vs Tumor/imunologia , Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/prevenção & controle , Humanos , Transfusão de Linfócitos , Prevenção Secundária , Linfócitos T/imunologia
15.
J Clin Invest ; 120(1): 343-56, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19955659

RESUMO

Thymic graft-versus-host disease (tGVHD) can contribute to profound T cell deficiency and repertoire restriction after allogeneic BM transplantation (allo-BMT). However, the cellular mechanisms of tGVHD and interactions between donor alloreactive T cells and thymic tissues remain poorly defined. Using clinically relevant murine allo-BMT models, we show here that even minimal numbers of donor alloreactive T cells, which caused mild nonlethal systemic graft-versus-host disease, were sufficient to damage the thymus, delay T lineage reconstitution, and compromise donor peripheral T cell function. Furthermore, to mediate tGVHD, donor alloreactive T cells required trafficking molecules, including CCR9, L selectin, P selectin glycoprotein ligand-1, the integrin subunits alphaE and beta7, CCR2, and CXCR3, and costimulatory/inhibitory molecules, including Ox40 and carcinoembryonic antigen-associated cell adhesion molecule 1. We found that radiation in BMT conditioning regimens upregulated expression of the death receptors Fas and death receptor 5 (DR5) on thymic stromal cells (especially epithelium), while decreasing expression of the antiapoptotic regulator cellular caspase-8-like inhibitory protein. Donor alloreactive T cells used the cognate proteins FasL and TNF-related apoptosis-inducing ligand (TRAIL) (but not TNF or perforin) to mediate tGVHD, thereby damaging thymic stromal cells, cytoarchitecture, and function. Strategies that interfere with Fas/FasL and TRAIL/DR5 interactions may therefore represent a means to attenuate tGVHD and improve T cell reconstitution in allo-BMT recipients.


Assuntos
Transplante de Medula Óssea/imunologia , Proteína Ligante Fas/fisiologia , Doença Enxerto-Hospedeiro/etiologia , Ligante Indutor de Apoptose Relacionado a TNF/fisiologia , Timo/imunologia , Animais , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/análise , Movimento Celular , Doença Enxerto-Hospedeiro/imunologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Receptores OX40/fisiologia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/agonistas , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/fisiologia , Células Estromais/fisiologia , Linfócitos T/imunologia , Timo/citologia , Transplante Homólogo
16.
J Exp Med ; 206(10): 2101-10, 2009 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-19737867

RESUMO

Nucleotide-binding oligomerization domain 2 (NOD2) polymorphisms are independent risk factors for Crohn's disease and graft-versus-host disease (GVHD). In Crohn's disease, the proinflammatory state resulting from NOD2 mutations have been associated with a loss of antibacterial function of enterocytes such as paneth cells. NOD2 has not been studied in experimental allogeneic bone marrow transplantation (allo-BMT). Using chimeric recipients with NOD2(-/-) hematopoietic cells, we demonstrate that NOD2 deficiency in host hematopoietic cells exacerbates GVHD. We found that proliferation and activation of donor T cells was enhanced in NOD-deficient allo-BMT recipients, suggesting that NOD2 plays a role in the regulation of host antigen-presenting cells (APCs). Next, we used bone marrow chimeras in an experimental colitis model and observed again that NOD2 deficiency in the hematopoietic cells results in increased intestinal inflammation. We conclude that NOD2 regulates the development of GVHD through its inhibitory effect on host APC function.


Assuntos
Doença Enxerto-Hospedeiro/etiologia , Sistema Hematopoético/fisiologia , Proteína Adaptadora de Sinalização NOD2/fisiologia , Animais , Células Apresentadoras de Antígenos/fisiologia , Transplante de Medula Óssea/imunologia , Colite/etiologia , Doença Enxerto-Hospedeiro/imunologia , Sistema Hematopoético/citologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Neoplasias Experimentais/imunologia , Proteína Adaptadora de Sinalização NOD2/genética , Polimorfismo de Nucleotídeo Único
17.
Blood ; 114(17): 3693-706, 2009 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-19666872

RESUMO

Alloreactive donor cytolytic T lymphocytes play a critical role in pathophysiology of acute graft-versus-host disease (GVHD). As GVHD progression involves tumor necrosis factor superfamily receptor activation, and as apoptotic signaling for some tumor necrosis factor superfamily receptors might involve acid sphingomyelinase (ASMase)-mediated ceramide generation, we hypothesized that ASMase deletion would ameliorate GVHD. Using clinically relevant mouse models of acute GVHD in which allogeneic bone marrow and T cells were transplanted into asmase+/+ and asmase(-/-) hosts, we identify host ASMase as critical for full-blown GVHD. Lack of host ASMase reduced the acute inflammatory phase of GVHD, attenuating cytokine storm, CD8+ T-cell proliferation/activation, and apoptosis of relevant graft-versus-host target cells (hepatocytes, intestinal, and skin cells). Organ injury was diminished in asmase(-/-) hosts, and morbidity and mortality improved at 90 days after transplantation. Resistance to cytolytic T lymphocyte-induced apoptosis was found at the target cell membrane if hepatocytes lack ASMase, as hepatocyte apoptosis required target cell ceramide generation for formation of ceramide-rich macrodomains, sites concentrating proapoptotic Fas. These studies indicate a requirement for target cell ASMase in evolution of GVHD in liver, small intestines, and skin and provide potential new targets for disease management.


Assuntos
Apoptose/imunologia , Linfócitos T CD8-Positivos/imunologia , Membrana Celular/imunologia , Ceramidas/imunologia , Doença Enxerto-Hospedeiro/imunologia , Esfingomielina Fosfodiesterase/fisiologia , Linfócitos T Citotóxicos/imunologia , Animais , Transplante de Medula Óssea , Membrana Celular/metabolismo , Membrana Celular/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Doença Enxerto-Hospedeiro/mortalidade , Doença Enxerto-Hospedeiro/patologia , Hepatócitos/imunologia , Hepatócitos/metabolismo , Interferon gama/metabolismo , Intestino Delgado/citologia , Intestino Delgado/imunologia , Intestino Delgado/metabolismo , Fígado/citologia , Fígado/imunologia , Fígado/metabolismo , Ativação Linfocitária , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos MRL lpr , Camundongos SCID , Pele/citologia , Pele/imunologia , Pele/metabolismo , Taxa de Sobrevida
18.
Blood ; 113(7): 1574-80, 2009 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-19011222

RESUMO

Keratinocyte growth factor (KGF), which is given exogenously to allogeneic bone marrow transplantation (allo-BMT) recipients, supports thymic epithelial cells and increases thymic output of naive T cells. Here, we demonstrate that this improved T-cell reconstitution leads to enhanced responses to DNA plasmid tumor vaccination. Tumor-bearing mice treated with KGF and DNA vaccination have improved long-term survival and decreased tumor burden after allo-BMT. When assayed before vaccination, KGF-treated allo-BMT recipients have increased numbers of peripheral T cells, including CD8(+) T cells with vaccine-recognition potential. In response to vaccination, KGF-treated allo-BMT recipients, compared with control subjects, generate increased numbers of tumor-specific CD8(+) cells, as well as increased numbers of CD8(+) cells producing interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha). We also found unanticipated benefits to antitumor immunity with the administration of KGF. KGF-treated allo-BMT recipients have an improved ratio of T effector cells to regulatory T cells, a larger fraction of effector cells that display a central memory phenotype, and effector cells that are derived from a broader T-cell-receptor repertoire. In conclusion, our data suggest that KGF can function as a potent vaccine adjuvant after allo-BMT through its effects on posttransplantation T-cell reconstitution.


Assuntos
Transplante de Medula Óssea/imunologia , Vacinas Anticâncer/imunologia , Fator 7 de Crescimento de Fibroblastos/farmacologia , Timo/efeitos dos fármacos , Vacinas de DNA/imunologia , Animais , Transplante de Medula Óssea/métodos , Transplante de Medula Óssea/mortalidade , Antígenos CD4/metabolismo , Linfócitos T CD8-Positivos/citologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/imunologia , Feminino , Fatores de Transcrição Forkhead/metabolismo , Memória Imunológica/efeitos dos fármacos , Memória Imunológica/imunologia , Contagem de Linfócitos , Camundongos , Camundongos Endogâmicos C57BL , Plasmídeos , Taxa de Sobrevida , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/metabolismo , Timo/citologia , Timo/imunologia , Quimeras de Transplante , Transplante Homólogo
19.
Blood ; 112(13): 5254-8, 2008 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-18838616

RESUMO

Graft-versus-host disease (GVHD) is a serious complication of allogeneic bone marrow transplantation, and donor T cells are indispensable for GVHD. Current therapies have limited efficacy, selectivity, and high toxicities. We used a novel flow cytometry technique for the analysis of intracellular phosphorylation events in single cells in murine BMT models to identify and validate novel GVHD drug targets.(1-7) This method circumvents the requirement for large numbers of purified cells, unlike western blots. We defined a signaling profile for alloactivated T cells in vivo and identified the phosphorylation of ERK1/2 and STAT-3 as important events during T-cell (allo)activation in GVHD. We establish that interference with STAT-3 phosphorylation can inhibit T-cell activation and proliferation in vitro and GVHD in vivo. This suggests that phospho-specific flow cytometry is useful for the identification of promising drug targets, and ERK1/2 and STAT-3 phosphorylation in alloactivated T cells may be important for GVHD.


Assuntos
Transplante de Medula Óssea/imunologia , Doença Enxerto-Hospedeiro , Ativação Linfocitária , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fator de Transcrição STAT3/metabolismo , Linfócitos T/imunologia , Animais , Citometria de Fluxo , Camundongos , Fosforilação/imunologia , Transplante Homólogo
20.
Blood ; 112(12): 4755-64, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-18815289

RESUMO

Delayed T-cell recovery is an important complication of allogeneic bone marrow transplantation (BMT). We demonstrate in murine models that donor BM-derived T cells display increased apoptosis in recipients of allogeneic BMT with or without GVHD. Although this apoptosis was associated with a loss of Bcl-2 and Bcl-X(L) expression, allogeneic recipients of donor BM deficient in Fas-, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)- or Bax-, or BM-overexpressing Bcl-2 or Akt showed no decrease in apoptosis of peripheral donor-derived T cells. CD44 expression was associated with an increased percentage of BM-derived apoptotic CD4(+) and CD8(+) T cells. Transplantation of RAG-2-eGFP-transgenic BM revealed that proliferating eGFP(lo)CD44(hi) donor BM-derived mature T cells were more likely to undergo to apoptosis than nondivided eGFP(hi)CD44(lo) recent thymic emigrants in the periphery. Finally, experiments using carboxyfluorescein succinimidyl ester-labeled T cells adoptively transferred into irradiated syngeneic hosts revealed that rapid spontaneous proliferation (as opposed to slow homeostatic proliferation) and acquisition of a CD44(hi) phenotype was associated with increased apoptosis in T cells. We conclude that apoptosis of newly generated donor-derived peripheral T cells after an allogeneic BMT contributes to delayed T-cell reconstitution and is associated with CD44 expression and rapid spontaneous proliferation by donor BM-derived T cells.


Assuntos
Apoptose , Transplante de Medula Óssea , Diferenciação Celular , Proliferação de Células , Receptores de Hialuronatos/metabolismo , Linfócitos T/fisiologia , Animais , Apoptose/genética , Apoptose/imunologia , Transplante de Medula Óssea/imunologia , Transplante de Medula Óssea/reabilitação , Diferenciação Celular/fisiologia , Células Cultivadas , Feminino , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Linfócitos T/citologia , Linfócitos T/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/genética , Ligante Indutor de Apoptose Relacionado a TNF/fisiologia , Fatores de Tempo , Transplante Homólogo , Proteína X Associada a bcl-2/genética , Receptor fas/genética , Receptor fas/fisiologia
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