RESUMO
Langerhans cell histiocytosis (LCH) is a myeloid neoplastic disorder characterized by lesions with CD1a-positive/Langerin (CD207)-positive histiocytes and inflammatory infiltrate that can cause local tissue damage and systemic inflammation. Clinical presentations range from single lesions with minimal impact to life-threatening disseminated disease. Therapy for systemic LCH has been established through serial trials empirically testing different chemotherapy agents and durations of therapy. However, fewer than 50% of patients who have disseminated disease are cured with the current standard-of-care vinblastine/prednisone/(mercaptopurine), and treatment failure is associated with long-term morbidity, including the risk of LCH-associated neurodegeneration. Historically, the nature of LCH-whether a reactive condition versus a neoplastic/malignant condition-was uncertain. Over the past 15 years, seminal discoveries have broadly defined LCH pathogenesis; specifically, activating mitogen-activated protein kinase pathway mutations (most frequently, BRAFV600E) in myeloid precursors drive lesion formation. LCH therefore is a clonal neoplastic disorder, although secondary inflammatory features contribute to the disease. These paradigm-changing insights offer a promise of rational cures for patients based on individual mutations, clonal reservoirs, and extent of disease. However, the pace of clinical trial development behind lags the kinetics of translational discovery. In this review, the authors discuss the current understanding of LCH biology, clinical characteristics, therapeutic strategies, and opportunities to improve outcomes for every patient through coordinated agent prioritization and clinical trial efforts.
Assuntos
Histiocitose de Células de Langerhans , Humanos , Histiocitose de Células de Langerhans/tratamento farmacológicoRESUMO
Histiocytoses constitute a heterogeneous group of rare disorders, characterised by infiltration of almost any organ by myeloid cells with diverse macrophage or dendritic cell phenotypes. Histiocytoses can start at any age. Diagnosis is based on histology in combination with appropriate clinical and radiological findings. The low incidence and broad spectrum of clinical manifestations often leads to diagnostic delay, especially for adults. In most cases, biopsy specimens infiltrated by histiocytes have somatic mutations in genes activating the MAP kinase cell-signalling pathway. These mutations might also be present in blood cells and haematopoietic progenitors of patients with multisystem disease. A comprehensive range of investigations and molecular typing are essential to accurately predict prognosis, which can vary from spontaneous resolution to life-threatening disseminated disease. Targeted therapies with BRAF or MEK inhibitors have revolutionised salvage treatment. However, the type and duration of treatment are still debated, and the prevention of neurological sequelae remains a crucial issue.
Assuntos
Diagnóstico Tardio , Histiócitos/patologia , Histiocitose de Células de Langerhans/diagnóstico por imagem , Mutação/genética , Adulto , Humanos , MAP Quinase Quinase Quinases , Macrófagos , Doenças RarasRESUMO
The extracellular signal-regulated kinase (ERK) signaling pathway is activated in Langerhans cell histiocytosis (LCH) histiocytes, but only 60% of cases carry somatic activating mutations of BRAF. To identify other genetic causes of ERK pathway activation, we performed whole exome sequencing on purified LCH cells in 3 cases. One patient with wild-type BRAF alleles in his histiocytes had compound mutations in the kinase domain of ARAF. Unlike wild-type ARAF, this mutant was a highly active mitogen-activated protein kinase kinase in vitro and was capable of transforming mouse embryo fibroblasts. Mutant ARAF activity was inhibited by vemurafenib, a BRAF inhibitor, indicating the importance of fully evaluating ERK pathway abnormalities in selecting LCH patients for targeted inhibitor therapy.
Assuntos
Histiocitose de Células de Langerhans/enzimologia , Histiocitose de Células de Langerhans/genética , Mutação , Proteínas Proto-Oncogênicas A-raf/genética , Animais , Células 3T3 BALB , Ativação Enzimática , Histiocitose de Células de Langerhans/patologia , Humanos , Células de Langerhans/enzimologia , Células de Langerhans/metabolismo , Células de Langerhans/patologia , Sistema de Sinalização das MAP Quinases , Camundongos , Proteínas Proto-Oncogênicas B-raf/genéticaRESUMO
Langerhans cell histiocytosis (LCH) remains a poorly understood disorder with heterogeneous clinical presentations characterized by focal or disseminated lesions that contain excessive CD1a+ langerin+ cells with dendritic cell features known as "LCH cells." Two of the major questions investigated over the past century have been (i) the origin of LCH cells and (ii) whether LCH is primarily an immune dysregulatory disorder or a neoplasm. Current opinion is that LCH cells are likely to arise from hematopoietic precursor cells, although the stage of derailment and site of transformation remain unclear and may vary in patients with different extent of disease. Over the years, evidence has provided the view that LCH is a neoplasm. The demonstration of clonality of LCH cells, insufficient evidence alone for neoplasia, is now bolstered by finding driver somatic mutations in BRAF in up to 55% of patients with LCH, and activation of the RAS-RAF-MEK-ERK (where MEK and ERK are mitogen-activated protein kinase and extracellular signal-regulated kinase, respectively) pathway in nearly 100% of patients with LCH. Herein, we review the evidence that recurrent genetic abnormalities characterized by activating oncogenic mutations should satisfy prerequisites for LCH to be called a neoplasm. As a consequence, recurrent episodes of LCH should be considered relapsed disease rather than disease reactivation. Mapping the complete genetic landscape of this intriguing disease will provide additional support for the conclusion that LCH is a neoplasm and is likely to provide more potential opportunities for molecularly targeted therapies.
Assuntos
Histiocitose de Células de Langerhans/genética , Neoplasias/genética , Evolução Clonal , Histiocitose de Células de Langerhans/tratamento farmacológico , Humanos , Sistema de Sinalização das MAP Quinases , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , RecidivaRESUMO
Langerhans cell histiocytosis (LCH) is now understood to be a neoplastic disease in which over 50% of cases have somatic activating mutations of BRAF. However, the extracellular signal-related (ERK) pathway is activated in all cases including those with wild type BRAF alleles. Here, we applied a targeted massively parallel sequencing panel to 30 LCH samples to test for the presence of additional genetic alterations that might cause ERK pathway activation. In 20 BRAF wild type samples, we found 3 somatic mutations in MAP2K1 (MEK1) including C121S and C121S/G128D in the kinase domain, and 56_61QKQKVG>R, an in-frame deletion in the N-terminal regulatory domain. All three variant proteins constitutively phosphorylated ERK in in vitro kinase assays. The C121S/G128D and 56_61QKQKVG>R variants were resistant to the mitogen-activated protein kinase kinase (MEK) inhibitor trametinib in vitro. Within the entire sample set, we found 3 specimens with mutations in MAP3K1 (MEKK1), including two truncation mutants, T779fs and T1481fs; T1481fs encoded an unstable and nonfunctional protein when expressed in vitro. T779fs was present in a specimen carrying BRAF V600E. The third variant was a single nucleotide substitution, E1286V, which was fully functional and is likely a germline polymorphism. These results indicate that LCH cells can harbor additional genetic alterations in the RAS-RAF-MEK pathway which, in the case of MAP2K1, may be responsible for ERK activation in a wild type BRAF setting. The resistance of some of these variants to trametinib may also have clinical implications for the combined use of RAF and MEK inhibitors in LCH.
Assuntos
Histiocitose de Células de Langerhans/genética , MAP Quinase Quinase 1/genética , MAP Quinase Quinase Quinase 1/genética , Mutação , Antineoplásicos/farmacologia , Humanos , MAP Quinase Quinase 1/metabolismo , MAP Quinase Quinase Quinase 1/metabolismo , Fosforilação/efeitos dos fármacos , Piridonas/farmacologia , Pirimidinonas/farmacologia , Transdução de SinaisRESUMO
To inform clinical trial design and real-world precision pediatric oncology practice, we classified diagnoses, assessed the landscape of mutations, and identified genomic variants matching trials in a large unselected institutional cohort of solid tumors patients sequenced at Dana-Farber / Boston Children's Cancer and Blood Disorders Center. Tumors were sequenced with OncoPanel, a targeted next-generation DNA sequencing panel. Diagnoses were classified according to the International Classification of Diseases for Oncology (ICD-O-3.2). Over 6.5 years, 888 pediatric cancer patients with 95 distinct diagnoses had successful tumor sequencing. Overall, 33% (n = 289/888) of patients had at least 1 variant matching a precision oncology trial protocol, and 14% (41/289) were treated with molecularly targeted therapy. This study highlights opportunities to use genomic data from hospital-based sequencing performed either for research or clinical care to inform ongoing and future precision oncology clinical trials. Furthermore, the study results emphasize the importance of data sharing to define the genomic landscape and targeted treatment opportunities for the large group of rare pediatric cancers we encounter in clinical practice.
Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Disseminação de Informação , Neoplasias , Medicina de Precisão , Humanos , Neoplasias/genética , Neoplasias/tratamento farmacológico , Criança , Medicina de Precisão/métodos , Masculino , Pré-Escolar , Feminino , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Adolescente , Lactente , Mutação , Ensaios Clínicos como Assunto , Terapia de Alvo Molecular/métodos , Genômica/métodos , Recém-NascidoRESUMO
Langerhans cell histiocytosis (LCH) is a proliferative disease of cells that share phenotypic characteristics with the primary antigen presenting cells of the epidermis. Its clinical manifestations are highly variable, extending from very benign forms to a disseminated, aggressive disease that causes significant mortality. Although many of the fundamental pathogenetic features of LCH have been enigmatic, recent advances have led to a much clearer understanding of the disease. In particular, careful molecular analyses of mouse models and human LCH samples suggest that LCH's cell of origin may not be the epidermal LC itself but a myeloid-derived precursor. Advanced genomic technologies have revealed the presence of activating, somatic BRAF mutations in the majority of patient specimens. Together, these observations have produced a new picture of LCH as a myeloid neoplasm. These advances are likely to have profound implications for the use of targeted therapeutics in LCH.
Assuntos
Histiocitose de Células de Langerhans/patologia , Animais , Histiocitose de Células de Langerhans/genética , Histiocitose de Células de Langerhans/terapia , HumanosRESUMO
Langerhans cell histiocytosis (LCH) has a broad spectrum of clinical behaviors; some cases are self-limited, whereas others involve multiple organs and cause significant mortality. Although Langerhans cells in LCH are clonal, their benign morphology and their lack (to date) of reported recurrent genomic abnormalities have suggested that LCH may not be a neoplasm. Here, using 2 orthogonal technologies for detecting cancer-associated mutations in formalin-fixed, paraffin-embedded material, we identified the oncogenic BRAF V600E mutation in 35 of 61 archived specimens (57%). TP53 and MET mutations were also observed in one sample each. BRAF V600E tended to appear in younger patients but was not associated with disease site or stage. Langerhans cells stained for phospho-mitogen-activated protein kinase kinase (phospho-MEK) and phospho-extracellular signal-regulated kinase (phospho-ERK) regardless of mutation status. High prevalence, recurrent BRAF mutations in LCH indicate that it is a neoplastic disease that may respond to RAF pathway inhibitors.
Assuntos
Predisposição Genética para Doença , Histiocitose de Células de Langerhans/genética , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Adolescente , Adulto , Substituição de Aminoácidos , Antígenos CD1/metabolismo , Criança , Pré-Escolar , Análise Mutacional de DNA , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Imunofluorescência , Genótipo , Histiocitose de Células de Langerhans/metabolismo , Histiocitose de Células de Langerhans/patologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Adulto JovemRESUMO
Tissue-resident mast cells (MCs) are important in allergic diseases. In a mouse model of allergic airways inflammation, an increase in peribronchiolar MCs was associated with increased concentrations of the chemokine CCL2 in lung lavage. MC progenitors (MCps) arising in bone marrow (BM) are recruited to tissues by transendothelial migration, and we found that CCL2 is chemotactic for MCps in freshly isolated BM in vitro. Immature, but not mature, BM-derived MCs migrated in response to CCL2 when cultured in IL-3+stem cell factor (SCF) but not when cultured in IL-3 alone. However, the cells under both culture conditions expressed mRNA for CCR2, the receptor for CCL2, and bound the radiolabeled chemokine with similar affinities, highlighting SCF as a key mediator in coupling CCR2 to downstream events, culminating in chemotaxis. Immature BM-derived MCs from IL-3 +SCF cultures, when administered i.v., accumulated at skin sites injected with CCL2 in vivo. MCp recruitment to the allergen-sensitized/challenged lung was significantly reduced in CCR2(-/-) and CCL2(-/-) mouse strains. However, reconstitution studies of sublethally irradiated and BM-reconstituted mice indicated that BM cells and stromal elements could provide CCL2, whereas the CCR2 function resided with stromal elements rather than BM cells. These experiments revealed a new function of SCF in chemokine receptor coupling, but they suggest a complex role of the CCL2/CCR2 axis in recruiting MCps during pulmonary inflammation.
Assuntos
Quimiocina CCL2/imunologia , Quimiotaxia de Leucócito/imunologia , Mastócitos/imunologia , Receptores CCR2/imunologia , Alérgenos/imunologia , Alérgenos/farmacologia , Animais , Líquido da Lavagem Broncoalveolar/imunologia , Quimiocina CCL2/metabolismo , Feminino , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/imunologia , Mastócitos/citologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Ovalbumina/farmacologia , Receptores CCR2/metabolismo , Hipersensibilidade Respiratória/imunologia , Hipersensibilidade Respiratória/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Células-Tronco/imunologia , Fator de Células-Tronco/metabolismoRESUMO
Widespread, comprehensive sequencing of patient tumors has facilitated the usage of precision medicine (PM) drugs to target specific genomic alterations. Therapeutic clinical trials are necessary to test new PM drugs to advance precision medicine, however, the abundance of patient sequencing data coupled with complex clinical trial eligibility has made it challenging to match patients to PM trials. To facilitate enrollment onto PM trials, we developed MatchMiner, an open-source platform to computationally match genomically profiled cancer patients to PM trials. Here, we describe MatchMiner's capabilities, outline its deployment at Dana-Farber Cancer Institute (DFCI), and characterize its impact on PM trial enrollment. MatchMiner's primary goals are to facilitate PM trial options for all patients and accelerate trial enrollment onto PM trials. MatchMiner can help clinicians find trial options for an individual patient or provide trial teams with candidate patients matching their trial's eligibility criteria. From March 2016 through March 2021, we curated 354 PM trials containing a broad range of genomic and clinical eligibility criteria and MatchMiner facilitated 166 trial consents (MatchMiner consents, MMC) for 159 patients. To quantify MatchMiner's impact on trial consent, we measured time from genomic sequencing report date to trial consent date for the 166 MMC compared to trial consents not facilitated by MatchMiner (non-MMC). We found MMC consented to trials 55 days (22%) earlier than non-MMC. MatchMiner has enabled our clinicians to match patients to PM trials and accelerated the trial enrollment process.
RESUMO
Multilevel genetic characterization of Waldenström macroglobulinemia (WM) is required to improve our understanding of the underlying molecular changes that lead to the initiation and progression of this disease. We performed microRNA-expression profiling of bone marrow-derived CD19(+) WM cells, compared with their normal cellular counterparts and validated data by quantitative reverse-transcription-polymerase chain reaction (qRT-PCR). We identified a WM-specific microRNA signature characterized by increased expression of microRNA-363*/-206/-494/-155/-184/-542-3p, and decreased expression of microRNA-9* (ANOVA; P < .01). We found that microRNA-155 regulates proliferation and growth of WM cells in vitro and in vivo, by inhibiting MAPK/ERK, PI3/AKT, and NF-kappaB pathways. Potential microRNA-155 target genes were identified using gene-expression profiling and included genes involved in cell-cycle progression, adhesion, and migration. Importantly, increased expression of the 6 miRNAs significantly correlated with a poorer outcome predicted by the International Prognostic Staging System for WM. We further demonstrated that therapeutic agents commonly used in WM alter the levels of the major miRNAs identified, by inducing downmodulation of 5 increased miRNAs and up-modulation of patient-downexpressed miRNA-9*. These data indicate that microRNAs play a pivotal role in the biology of WM; represent important prognostic marker; and provide the basis for the development of new microRNA-based targeted therapies in WM.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , MicroRNAs/genética , Neoplasias Experimentais/patologia , Macroglobulinemia de Waldenstrom/tratamento farmacológico , Macroglobulinemia de Waldenstrom/genética , Idoso , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Murinos , Medula Óssea/metabolismo , Medula Óssea/patologia , Ácidos Borônicos/administração & dosagem , Bortezomib , Estudos de Casos e Controles , Adesão Celular/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Feminino , Citometria de Fluxo , Imunofluorescência , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteínas de Fluorescência Verde/metabolismo , Humanos , Linfócitos/metabolismo , Linfócitos/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Neoplasias Experimentais/tratamento farmacológico , Análise de Sequência com Séries de Oligonucleotídeos , Fosfatidilinositol 3-Quinases/metabolismo , Prognóstico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirazinas/administração & dosagem , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rituximab , Transdução de Sinais , Macroglobulinemia de Waldenstrom/metabolismo , Macroglobulinemia de Waldenstrom/patologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
The interaction of multiple myeloma (MM) cells with the bone marrow (BM) milieu plays a crucial role in MM pathogenesis. Stromal cell-derived factor-1 (SDF1) regulates homing of MM cells to the BM. In this study, we examined the role of RhoA and Rac1 GTPases in SDF1-induced adhesion and chemotaxis of MM. We found that both RhoA and Rac1 play key roles in SDF1-induced adhesion of MM cells to BM stromal cells, whereas RhoA was involved in chemotaxis and motility. Furthermore, both ROCK and Rac1 inhibitors reduced SDF1-induced polymerization of actin and activation of LIMK, SRC, FAK, and cofilin. Moreover, RhoA and Rac1 reduced homing of MM cells to BM niches. In conclusion, we characterized the role of RhoA and Rac1 GTPases in SDF1-induced adhesion, chemotaxis, and homing of MM cells to the BM, providing the framework for targeting RhoA and Rac1 GTPases as novel MM therapy.
Assuntos
Adesão Celular , Quimiocina CXCL12/fisiologia , Quimiotaxia , Mieloma Múltiplo/patologia , Proteínas rac1 de Ligação ao GTP/fisiologia , Proteína rhoA de Ligação ao GTP/fisiologia , Animais , Medula Óssea , Proteínas do Citoesqueleto/metabolismo , Humanos , Camundongos , Camundongos SCID , Células Estromais , Células Tumorais CultivadasRESUMO
Detailed genomic studies have shown that cytogenetic abnormalities contribute to multiple myeloma (MM) pathogenesis and disease progression. Nevertheless, little is known about the characteristics of MM at the epigenetic level and specifically how microRNAs regulate MM progression in the context of the bone marrow milieu. Therefore, we performed microRNA expression profiling of bone marrow derived CD138(+) MM cells versus their normal cellular counterparts and validated data by qRT-PCR. We identified a MM-specific microRNA signature characterized by down-expression of microRNA-15a/-16 and overexpression of microRNA-222/-221/-382/-181a/-181b (P < .01). We investigated the functional role of microRNA-15a and -16 and showed that they regulate proliferation and growth of MM cells in vitro and in vivo by inhibiting AKT serine/threonine-protein-kinase (AKT3), ribosomal-protein-S6, MAP-kinases, and NF-kappaB-activator MAP3KIP3. Moreover, miRNA-15a and -16 exerted their anti-MM activity even in the context of the bone marrow milieu in vitro and in vivo. These data indicate that microRNAs play a pivotal role in the biology of MM and represent important targets for novel therapies in MM.
Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs/fisiologia , Mieloma Múltiplo/patologia , RNA Neoplásico/fisiologia , Inibidores da Angiogênese/fisiologia , Animais , Adesão Celular , Divisão Celular/fisiologia , Ensaios Clínicos Fase II como Assunto/estatística & dados numéricos , Técnicas de Cocultura , Células Endoteliais/citologia , Perfilação da Expressão Gênica , Humanos , Camundongos , Camundongos SCID , MicroRNAs/biossíntese , MicroRNAs/genética , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/metabolismo , Prognóstico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , Proteína S6 Ribossômica/antagonistas & inibidores , Proteína S6 Ribossômica/metabolismo , Células Estromais/citologiaRESUMO
The interaction of multiple myeloma (MM) cells with their microenvironment in the bone marrow (BM) provides a protective environment and resistance to therapeutic agents. We hypothesized that disruption of the interaction of MM cells with their BM milieu would lead to their sensitization to therapeutic agents such as bortezomib, melphalan, doxorubicin, and dexamethasone. We report that the CXCR4 inhibitor AMD3100 induces disruption of the interaction of MM cells with the BM reflected by mobilization of MM cells into the circulation in vivo, with kinetics that differed from that of hematopoietic stem cells. AMD3100 enhanced sensitivity of MM cell to multiple therapeutic agents in vitro by disrupting adhesion of MM cells to bone marrow stromal cells (BMSCs). Moreover, AMD3100 increased mobilization of MM cells to the circulation in vivo, increased the ratio of apoptotic circulating MM cells, and enhanced the tumor reduction induced by bortezomib. Mechanistically, AMD3100 significantly inhibited Akt phosphorylation and enhanced poly(ADP-ribose) polymerase (PARP) cleavage as a result of bortezomib, in the presence of BMSCs in coculture. These experiments provide a proof of concept for the use of agents that disrupt interaction with the microenvironment for enhancement of efficacy of cytotoxic agents in cancer therapy.
Assuntos
Fármacos Anti-HIV/farmacologia , Antineoplásicos/farmacologia , Medula Óssea/metabolismo , Compostos Heterocíclicos/farmacologia , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/metabolismo , Receptores CXCR4/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Benzilaminas , Ácidos Borônicos/farmacologia , Bortezomib , Adesão Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Ensaio de Unidades Formadoras de Colônias , Ciclamos , Resistencia a Medicamentos Antineoplásicos , Fibronectinas/metabolismo , Citometria de Fluxo , Humanos , Immunoblotting , Técnicas Imunoenzimáticas , Integrina alfa4beta1/genética , Integrina alfa4beta1/metabolismo , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Lentivirus/genética , Masculino , Camundongos , Camundongos SCID , Pirazinas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Células Estromais/metabolismo , Transfecção , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The study and treatment of age-related macular degeneration (AMD), a leading cause of blindness, has been hampered by a lack of animal models. Here we report that mice deficient either in monocyte chemoattractant protein-1 (Ccl-2; also known as MCP-1) or its cognate C-C chemokine receptor-2 (Ccr-2) develop cardinal features of AMD, including accumulation of lipofuscin in and drusen beneath the retinal pigmented epithelium (RPE), photoreceptor atrophy and choroidal neovascularization (CNV). Complement and IgG deposition in RPE and choroid accompanies senescence in this model, as in human AMD. RPE or choroidal endothelial production of Ccl-2 induced by complement C5a and IgG may mediate choroidal macrophage infiltration into aged wild-type choroids. Wild-type choroidal macrophages degrade C5 and IgG in eye sections of Ccl2(-/-) or Ccr2(-/-) mice. Impaired macrophage recruitment may allow accumulation of C5a and IgG, which induces vascular endothelial growth factor (VEGF) production by RPE, possibly mediating development of CNV. These models implicate macrophage dysfunction in AMD pathogenesis and may be useful as a platform for validating therapies.
Assuntos
Inflamação/metabolismo , Macrófagos/metabolismo , Degeneração Macular/metabolismo , Retina/patologia , Envelhecimento/imunologia , Envelhecimento/metabolismo , Animais , Quimiocina CCL2/genética , Quimiocina CCL2/imunologia , Quimiocina CCL2/metabolismo , Complemento C5a/metabolismo , Proteínas do Sistema Complemento/metabolismo , Imunoglobulina G/metabolismo , Inflamação/imunologia , Macrófagos/imunologia , Degeneração Macular/imunologia , Camundongos , Receptores CCR2 , Receptores de Quimiocinas/genética , Receptores de Quimiocinas/imunologia , Receptores de Quimiocinas/metabolismo , Retina/imunologia , Retina/metabolismoRESUMO
PURPOSE: In contrast to recurrence after initial diagnosis of stage I-III breast cancer [recurrent metastatic breast cancer (rMBC)], de novo metastatic breast cancer (dnMBC) represents a unique setting to elucidate metastatic drivers in the absence of treatment selection. We present the genomic landscape of dnMBC and association with overall survival (OS). EXPERIMENTAL DESIGN: Targeted DNA sequencing (OncoPanel) was prospectively performed on either primary or metastatic tumors from 926 patients (212 dnMBC and 714 rMBC). Single-nucleotide variants, copy-number variations, and tumor mutational burden (TMB) in treatment-naïve dnMBC primary tumors were compared with primary tumors in patients who ultimately developed rMBC, and correlated with OS across all dnMBC. RESULTS: When comparing primary tumors by subtype, MYB amplification was enriched in triple-negative dnMBC versus rMBC (21.1% vs. 0%, P = 0.0005, q = 0.111). Mutations in KMTD2, SETD2, and PIK3CA were more prevalent, and TP53 and BRCA1 less prevalent, in primary HR+/HER2- tumors of dnMBC versus rMBC, though not significant after multiple comparison adjustment. Alterations associated with shorter OS in dnMBC included TP53 (wild-type: 79.7 months; altered: 44.2 months; P = 0.008, q = 0.107), MYC (79.7 vs. 23.3 months; P = 0.0003, q = 0.011), and cell-cycle (122.7 vs. 54.9 months; P = 0.034, q = 0.245) pathway genes. High TMB correlated with better OS in triple-negative dnMBC (P = 0.041). CONCLUSIONS: Genomic differences between treatment-naïve dnMBC and primary tumors of patients who developed rMBC may provide insight into mechanisms underlying metastatic potential and differential therapeutic sensitivity in dnMBC. Alterations associated with poor OS in dnMBC highlight the need for novel approaches to overcome potential intrinsic resistance to current treatments.
Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama Masculina/genética , Neoplasias da Mama/genética , Recidiva Local de Neoplasia/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Neoplasias da Mama Masculina/diagnóstico , Neoplasias da Mama Masculina/mortalidade , Neoplasias da Mama Masculina/patologia , Feminino , Genômica , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Mutação , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Adulto JovemRESUMO
Langerhans cell histiocytosis (LCH) is characterized by the accumulation of Langerin (CD207)-expressing histiocytes. Mutational activation of mitogen-activated protein kinase pathway genes, in particular BRAF, drives most cases. To test whether activated BRAF is sufficient for the development of LCH, we engineered mice to express BRAF V600E under the control of the human Langerin promoter. These mice have shortened survivals, smaller lymphoid organs, absent Leydig cells, and fewer epidermal LCs than controls, but do not accumulate histiocytes. To test whether the absence of histiocyte proliferation could be due to oncogene-induced senescence, we engineered homozygous Pten loss in the same cells that expressed BRAF V600E. Like mice with intact Pten, these mice have shortened survivals, smaller thymi, and absent Leydig cells. However, loss of Pten also leads to the accumulation of CD207+ histiocytes in spleen, thymus, and some lymph nodes. While many CD207+ histiocytes in the thymus are CD8-, reminiscent of LCH cells, the CD207+ histiocytes in the spleen and lymph nodes are CD8+. These mice also accumulate large numbers of CD207- cells in the lamina propria (LP) of the small intestine. Both the lymphoid and LP phenotypes are likely due to human Langerin promoter-driven BRAF V600E expression in resident CD8+ dendritic cells in the former and LP dendritic cells in the latter and confirm that Pten loss is required to overcome inhibitory pathways induced by BRAF V600E expression. The complex phenotype of these mice is a consequence of the multiple murine cell types in which the human Langerin promoter is active.