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1.
Nat Commun ; 12(1): 4700, 2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34349124

RESUMO

During skin injury, immune response and repair mechanisms have to be coordinated for rapid skin regeneration and the prevention of microbial infections. Natural Killer (NK) cells infiltrate hypoxic skin lesions and Hypoxia-inducible transcription factors (HIFs) mediate adaptation to low oxygen. We demonstrate that mice lacking the Hypoxia-inducible factor (HIF)-1α isoform in NK cells show impaired release of the cytokines Interferon (IFN)-γ and Granulocyte Macrophage - Colony Stimulating Factor (GM-CSF) as part of a blunted immune response. This accelerates skin angiogenesis and wound healing. Despite rapid wound closure, bactericidal activity and the ability to restrict systemic bacterial infection are impaired. Conversely, forced activation of the HIF pathway supports cytokine release and NK cell-mediated antibacterial defence including direct killing of bacteria by NK cells despite delayed wound closure. Our results identify, HIF-1α in NK cells as a nexus that balances antimicrobial defence versus global repair in the skin.


Assuntos
Células Matadoras Naturais/imunologia , Pele/imunologia , Pele/microbiologia , Cicatrização , Animais , Hipóxia Celular , Citocinas/metabolismo , Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/patologia , Camundongos , Neovascularização Fisiológica , Pele/irrigação sanguínea , Dermatopatias Bacterianas/prevenção & controle
2.
Nat Commun ; 12(1): 5056, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34417458

RESUMO

Melanoma cells rely on developmental programs during tumor initiation and progression. Here we show that the embryonic stem cell (ESC) factor Sall4 is re-expressed in the Tyr::NrasQ61K; Cdkn2a-/- melanoma model and that its expression is necessary for primary melanoma formation. Surprisingly, while Sall4 loss prevents tumor formation, it promotes micrometastases to distant organs in this melanoma-prone mouse model. Transcriptional profiling and in vitro assays using human melanoma cells demonstrate that SALL4 loss induces a phenotype switch and the acquisition of an invasive phenotype. We show that SALL4 negatively regulates invasiveness through interaction with the histone deacetylase (HDAC) 2 and direct co-binding to a set of invasiveness genes. Consequently, SALL4 knock down, as well as HDAC inhibition, promote the expression of an invasive signature, while inhibition of histone acetylation partially reverts the invasiveness program induced by SALL4 loss. Thus, SALL4 appears to regulate phenotype switching in melanoma through an HDAC2-mediated mechanism.


Assuntos
Epigênese Genética , Melanoma/genética , Melanoma/patologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Fator de Células-Tronco/metabolismo , Fatores de Transcrição/metabolismo , Acetilação , Animais , Sequência de Bases , Carcinogênese/genética , Carcinogênese/patologia , Adesão Celular/genética , Linhagem Celular Tumoral , Linhagem da Célula , Proliferação de Células , Proteínas de Ligação a DNA/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Histona Desacetilase 2/metabolismo , Histonas/metabolismo , Humanos , Melanócitos/metabolismo , Melanócitos/patologia , Camundongos Nus , Camundongos Transgênicos , Invasividade Neoplásica , Micrometástase de Neoplasia , Ligação Proteica , Carga Tumoral
4.
Stem Cells Transl Med ; 10(4): 522-533, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33258291

RESUMO

Melanoma is the deadliest of all skin cancers due to its high metastatic potential. In recent years, advances in targeted therapy and immunotherapy have contributed to a remarkable progress in the treatment of metastatic disease. However, intrinsic or acquired resistance to such therapies remains a major obstacle in melanoma treatment. Melanoma disease progression, beginning from tumor initiation and growth to acquisition of invasive phenotypes and metastatic spread and acquisition of treatment resistance, has been associated with cellular dedifferentiation and the hijacking of gene regulatory networks reminiscent of the neural crest (NC)-the developmental structure which gives rise to melanocytes and hence melanoma. This review summarizes the experimental evidence for the involvement of NC stem cell (NCSC)-like cell states during melanoma progression and addresses novel approaches to combat the emergence of stemness characteristics that have shown to be linked with aggressive disease outcome and drug resistance.

5.
Nat Commun ; 10(1): 2192, 2019 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-31097699

RESUMO

The transcription factor Yin Yang 1 (YY1) plays an important role in human disease. It is often overexpressed in cancers and mutations can lead to a congenital haploinsufficiency syndrome characterized by craniofacial dysmorphisms and neurological dysfunctions, consistent with a role in brain development. Here, we show that Yy1 controls murine cerebral cortex development in a stage-dependent manner. By regulating a wide range of metabolic pathways and protein translation, Yy1 maintains proliferation and survival of neural progenitor cells (NPCs) at early stages of brain development. Despite its constitutive expression, however, the dependence on Yy1 declines over the course of corticogenesis. This is associated with decreasing importance of processes controlled by Yy1 during development, as reflected by diminished protein synthesis rates at later developmental stages. Thus, our study unravels a novel role for Yy1 as a stage-dependent regulator of brain development and shows that biosynthetic demands of NPCs dynamically change throughout development.


Assuntos
Córtex Cerebral/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Células-Tronco Neurais/fisiologia , Fator de Transcrição YY1/fisiologia , Animais , Proliferação de Células/genética , Sobrevivência Celular/genética , Células Cultivadas , Embrião de Mamíferos , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular/genética , Técnicas de Inativação de Genes , Redes e Vias Metabólicas/fisiologia , Camundongos , Camundongos Transgênicos , Modelos Animais , Cultura Primária de Células , RNA Interferente Pequeno/metabolismo
6.
J Clin Invest ; 129(7): 2702-2716, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-31039140

RESUMO

The development of metastatic melanoma is thought to require the dynamic shifting of neoplastic cells between proliferative and invasive phenotypes. Contrary to this conventional "phenotype switching" model, we now show that disease progression can involve malignant melanoma cells simultaneously displaying proliferative and invasive properties. Using a genetic mouse model of melanoma in combination with in vitro analyses of melanoma cell lines, we found that conditional deletion of the downstream signaling molecule Smad4, which abrogates all canonical TGF-ß signaling, indeed inhibits both tumor growth and metastasis. Conditional deletion of the inhibitory signaling factor Smad7, however, generated cells that are both highly invasive and proliferative, indicating that invasiveness is compatible with a high proliferation rate. In fact, conditional Smad7 deletion led to sustained melanoma growth and at the same time promoted massive metastasis formation, a result consistent with data indicating that low SMAD7 levels in patient tumors are associated with a poor survival. Our findings reveal that modulation of SMAD7 levels can overcome the need for phenotype switching during tumor progression and may thus represent a novel therapeutic target in metastatic disease.


Assuntos
Melanoma/metabolismo , Transdução de Sinais , Proteína Smad7/metabolismo , Animais , Intervalo Livre de Doença , Humanos , Melanoma/genética , Melanoma/mortalidade , Melanoma/patologia , Camundongos , Camundongos Knockout , Invasividade Neoplásica , Metástase Neoplásica , Proteína Smad4/genética , Proteína Smad4/metabolismo , Proteína Smad7/genética , Taxa de Sobrevida
7.
Cell Stem Cell ; 24(4): 637-653.e9, 2019 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-30951662

RESUMO

Increasing evidence suggests that cancer cells highjack developmental programs for disease initiation and progression. Melanoma arises from melanocytes that originate during development from neural crest stem cells (NCSCs). Here, we identified the transcription factor Yin Yang 1 (Yy1) as an NCSCs regulator. Conditional deletion of Yy1 in NCSCs resulted in stage-dependent hypoplasia of all major neural crest derivatives due to decreased proliferation and increased cell death. Moreover, conditional ablation of one Yy1 allele in a melanoma mouse model prevented tumorigenesis, indicating a particular susceptibility of melanoma cells to reduced Yy1 levels. Combined RNA sequencing (RNA-seq), chromatin immunoprecipitation (ChIP)-seq, and untargeted metabolomics demonstrated that YY1 governs multiple metabolic pathways and protein synthesis in both NCSCs and melanoma. In addition to directly regulating a metabolic gene set, YY1 can act upstream of MITF/c-MYC as part of a gene regulatory network controlling metabolism. Thus, both NCSC development and melanoma formation depend on an intricate YY1-controlled metabolic program.


Assuntos
Melanoma/metabolismo , Melanoma/patologia , Crista Neural/citologia , Crista Neural/metabolismo , Fator de Transcrição YY1/metabolismo , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Fator de Transcrição YY1/deficiência
8.
Cancer Cell ; 34(1): 69-84.e14, 2018 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-30008323

RESUMO

Human melanomas frequently harbor amplifications of EZH2. However, the contribution of EZH2 to melanoma formation has remained elusive. Taking advantage of murine melanoma models, we show that EZH2 drives tumorigenesis from benign BrafV600E- or NrasQ61K-expressing melanocytes by silencing of genes relevant for the integrity of the primary cilium, a signaling organelle projecting from the surface of vertebrate cells. Consequently, gain of EZH2 promotes loss of primary cilia in benign melanocytic lesions. In contrast, blockade of EZH2 activity evokes ciliogenesis and cilia-dependent growth inhibition in malignant melanoma. Finally, we demonstrate that loss of cilia enhances pro-tumorigenic WNT/ß-catenin signaling, and is itself sufficient to drive metastatic melanoma in benign cells. Thus, primary cilia deconstruction is a key process in EZH2-driven melanomagenesis.


Assuntos
Movimento Celular , Proliferação de Células , Cílios/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Melanócitos/metabolismo , Melanoma/metabolismo , Neoplasias Cutâneas/metabolismo , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Cílios/genética , Cílios/patologia , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Feminino , GTP Fosfo-Hidrolases/genética , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Metástase Linfática , Masculino , Melanócitos/patologia , Melanoma/genética , Melanoma/secundário , Proteínas de Membrana/genética , Camundongos Nus , Camundongos Transgênicos , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Via de Sinalização Wnt , beta Catenina/genética , beta Catenina/metabolismo
9.
Dev Biol ; 444 Suppl 1: S356-S365, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29778801

RESUMO

Multipotent neural crest cells can self-renew and give rise to a plethora of neural and non-neural cell types in the vertebrate embryo. Intriguingly, cells reminiscent of such neural crest stem cells (NCSCs) have also been isolated from various postnatal and adult neural crest (NC)-derived structures. However, it has been debated whether NCSC-like cells in the adult correspond to 'in vitro artefacts' emerging upon isolation or fulfil a physiological role in vivo. Here, we discuss recent findings indicating that in different adult NC derivatives, injury or stress responses induce a NCSC-like state, presumably by reprogramming differentiated cells such as Schwann cells. Thereby, injury or stress appear to endow NC-derived cells with the capacity to generate new cell types during the repair process; in addition, injury can activate a repair program in adult NC-derived cells, which promotes tissue repair or regeneration by paracrine signalling. Thus, there is increasing evidence that NCSC-like cells in NC derivatives represent an in vivo state implicated in distinct physiological functions in the adult organism.


Assuntos
Células-Tronco Neurais/metabolismo , Estresse Fisiológico/fisiologia , Cicatrização/fisiologia , Adulto , Animais , Diferenciação Celular , Movimento Celular , Proliferação de Células/fisiologia , Células Cultivadas , Humanos , Crista Neural/metabolismo , Crista Neural/fisiologia , Neurogênese/fisiologia , Células de Schwann , Ferimentos e Lesões/fisiopatologia
10.
Genesis ; 56(6-7): e23105, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29673028

RESUMO

The neural crest is one of the embryonic structures with the broadest developmental potential in vertebrates. Morphologically, neural crest cells emerge during neurulation in the dorsal folds of the neural tube before undergoing an epithelial-to-mesenchymal transition (EMT), delaminating from the neural tube, and migrating to multiple sites in the growing embryo. Neural crest cells generate cell types as diverse as peripheral neurons and glia, melanocytes, and so-called mesectodermal derivatives that include craniofacial bone and cartilage and smooth muscle cells in cardiovascular structures. In mice, the fate of neural crest cells has been determined mainly by means of transgenesis and genome editing technologies. The most frequently used method relies on the Cre-loxP system, in which expression of Cre-recombinase in neural crest cells or their derivatives genetically enables the expression of a Cre-reporter allele, thus permanently marking neural crest-derived cells. Here, we provide an overview of the Cre-driver lines used in the field and discuss to what extent these lines allow precise neural crest stage and lineage-specific fate mapping.


Assuntos
Linhagem da Célula/fisiologia , Crista Neural/embriologia , Animais , Diferenciação Celular/fisiologia , Movimento Celular/fisiologia , Mapeamento Cromossômico/métodos , Transição Epitelial-Mesenquimal/fisiologia , Integrases/metabolismo , Camundongos , Tubo Neural/embriologia
11.
Nat Commun ; 9(1): 314, 2018 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-29358574

RESUMO

The originally published version of this Article was updated shortly after publication to add the words 'The' and 'affinity' to the title, following their inadvertent removal during the production process. This has now been corrected in both the PDF and HTML versions of the Article.

12.
Nat Commun ; 9(1): 236, 2018 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-29339718

RESUMO

Cutaneous wound healing is a complex process that aims to re-establish the original structure of the skin and its functions. Among other disorders, peripheral neuropathies are known to severely impair wound healing capabilities of the skin, revealing the importance of skin innervation for proper repair. Here, we report that peripheral glia are crucially involved in this process. Using a mouse model of wound healing, combined with in vivo fate mapping, we show that injury activates peripheral glia by promoting de-differentiation, cell-cycle re-entry and dissemination of the cells into the wound bed. Moreover, injury-activated glia upregulate the expression of many secreted factors previously associated with wound healing and promote myofibroblast differentiation by paracrine modulation of TGF-ß signalling. Accordingly, depletion of these cells impairs epithelial proliferation and wound closure through contraction, while their expansion promotes myofibroblast formation. Thus, injury-activated glia and/or their secretome might have therapeutic potential in human wound healing disorders.


Assuntos
Diferenciação Celular/fisiologia , Neuroglia/fisiologia , Pele/fisiopatologia , Cicatrização/fisiologia , Animais , Ciclo Celular/genética , Ciclo Celular/fisiologia , Diferenciação Celular/genética , Células Cultivadas , Perfilação da Expressão Gênica , Humanos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Knockout , Camundongos Transgênicos , Miofibroblastos/metabolismo , Miofibroblastos/fisiologia , Neuroglia/citologia , Neuroglia/metabolismo , Fatores de Transcrição SOXE/genética , Fatores de Transcrição SOXE/metabolismo , Transdução de Sinais/genética , Pele/lesões , Pele/inervação , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Cicatrização/genética
14.
Nat Commun ; 8(1): 1988, 2017 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-29215016

RESUMO

Cutaneous melanoma represents the most fatal skin cancer due to its high metastatic capacity. According to the "phenotype switching" model, the aggressive nature of melanoma cells results from their intrinsic potential to dynamically switch from a high-proliferative/low-invasive to a low-proliferative/high-invasive state. Here we identify the low affinity neurotrophin receptor CD271 as a key effector of phenotype switching in melanoma. CD271 plays a dual role in this process by decreasing proliferation, while simultaneously promoting invasiveness. Dynamic modification of CD271 expression allows tumor cells to grow at low levels of CD271, to reduce growth and invade when CD271 expression is high, and to re-expand at a distant site upon decrease of CD271 expression. Mechanistically, the cleaved intracellular domain of CD271 controls proliferation, while the interaction of CD271 with the neurotrophin receptor Trk-A modulates cell adhesiveness through dynamic regulation of a set of cholesterol synthesis genes relevant for patient survival.


Assuntos
Regulação Neoplásica da Expressão Gênica , Melanoma/patologia , Proteínas do Tecido Nervoso/metabolismo , Receptor trkA/metabolismo , Receptores de Fator de Crescimento Neural/metabolismo , Neoplasias Cutâneas/patologia , Animais , Adesão Celular , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Fibroblastos , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Queratinócitos , Masculino , Melanoma/genética , Melanoma/mortalidade , Camundongos , Camundongos Nus , Invasividade Neoplásica/patologia , Domínios Proteicos , RNA Interferente Pequeno/metabolismo , Receptor trkA/genética , Pele/citologia , Pele/patologia , Técnicas de Cultura de Tecidos , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Nat Commun ; 8(1): 1466, 2017 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-29133867

RESUMO

Renal angiomyolipomas (AML) contain an admixture of clonal tumour cells with features of several different mesenchymal lineages, implying the existence of an unidentified AML neoplastic stem cell. Biallelic inactivation of TSC2 or TSC1 is believed to represent the driving event in these tumours. Here we show that TSC2 knockdown transforms senescence-resistant cultured mouse and human renal epithelial cells into neoplastic stem cells that serially propagate renal AML-like tumours in mice. mTOR inhibitory therapy of mouse AML allografts mimics the clinical responses of human renal AMLs. Deletion of Tsc1 in mouse renal epithelia causes differentiation in vivo into cells expressing characteristic AML markers. Human renal AML and a renal AML cell line express proximal tubule markers. We describe the first mouse models of renal AML and provide evidence that these mesenchymal tumours originate from renal proximal tubule epithelial cells, uncovering an unexpected pathological differentiation plasticity of the proximal tubule.


Assuntos
Angiomiolipoma/patologia , Células Epiteliais/citologia , Neoplasias Renais/patologia , Túbulos Renais Proximais/citologia , Células-Tronco Neoplásicas/citologia , Proteínas Supressoras de Tumor/genética , Animais , Diferenciação Celular/genética , Células Epiteliais/patologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos SCID , Transplante de Neoplasias , Interferência de RNA , RNA Interferente Pequeno/genética , Esferoides Celulares , Serina-Treonina Quinases TOR/antagonistas & inibidores , Transplante Heterólogo , Proteína 1 do Complexo Esclerose Tuberosa , Proteína 2 do Complexo Esclerose Tuberosa , Células Tumorais Cultivadas , Proteínas Supressoras de Tumor/metabolismo
16.
Cell Stem Cell ; 21(5): 679-693.e6, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-29033351

RESUMO

To identify the cells at the origin of melanoma, we combined single-cell lineage-tracing and transcriptomics approaches with time-lapse imaging. A mouse model that recapitulates key histopathological features of human melanomagenesis was created by inducing a BRafV600E-driven melanomagenic program in tail interfollicular melanocytes. Most targeted mature, melanin-producing melanocytes expanded clonally within the epidermis before losing their differentiated features through transcriptional reprogramming and eventually invading the dermis. Tumors did not form within interscales, which contain both mature and dormant amelanotic melanocytes. The hair follicle bulge, which contains melanocyte stem cells, was also refractory to melanomagenesis. These studies identify varying tumor susceptibilities within the melanocytic lineage, highlighting pigment-producing cells as the melanoma cell of origin, and indicate that regional variation in tumor predisposition is dictated by microenvironmental cues rather than intrinsic differences in cellular origin. Critically, this work provides in vivo evidence that differentiated somatic cells can be reprogrammed into cancer initiating cells.


Assuntos
Desdiferenciação Celular , Melanócitos/patologia , Melanoma/genética , Mutação/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genética , Pigmentação da Pele , Animais , Biomarcadores/metabolismo , Carcinogênese/metabolismo , Carcinogênese/patologia , Proliferação de Células , Derme/patologia , Folículo Piloso/patologia , Humanos , Melanócitos/metabolismo , Melanoma/patologia , Camundongos , Invasividade Neoplásica , Neoplasias Cutâneas/patologia , Nicho de Células-Tronco , Cauda , Transcriptoma/genética
17.
Cell Rep ; 20(4): 854-867, 2017 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-28746871

RESUMO

Immunotherapy and particularly immune checkpoint inhibitors have resulted in remarkable clinical responses in patients with immunogenic tumors, although most cancers develop resistance to immunotherapy. The molecular mechanisms of tumor resistance to immunotherapy remain poorly understood. We now show that induction of the histone methyltransferase Ezh2 controls several tumor cell-intrinsic and extrinsic resistance mechanisms. Notably, T cell infiltration selectively correlated with high EZH2-PRC2 complex activity in human skin cutaneous melanoma. During anti-CTLA-4 or IL-2 immunotherapy in mice, intratumoral tumor necrosis factor-α (TNF-α) production and T cell accumulation resulted in increased Ezh2 expression in melanoma cells, which in turn silenced their own immunogenicity and antigen presentation. Ezh2 inactivation reversed this resistance and synergized with anti-CTLA-4 and IL-2 immunotherapy to suppress melanoma growth. These anti-tumor effects depended on intratumorally accumulating interferon-γ (IFN-γ)-producing PD-1low CD8+ T cells and PD-L1 downregulation on melanoma cells. Hence, Ezh2 serves as a molecular switch controlling melanoma escape during T cell-targeting immunotherapies.


Assuntos
Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Linfócitos T/metabolismo , Animais , Western Blotting , Antígeno CTLA-4/metabolismo , Linhagem Celular , Imunoprecipitação da Cromatina , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Imunofluorescência , Humanos , Imunoterapia , Interleucina-2/metabolismo , Melanoma/metabolismo , Melanoma/terapia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Fator de Necrose Tumoral alfa/metabolismo
18.
Curr Opin Neurobiol ; 47: 16-23, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28753439

RESUMO

The neural crest is a transient structure in vertebrate embryos that produces migratory cells with an astonishing developmental potential. While neural crest fate maps have originally been established through interspecies transplantation assays, dye labeling, and retroviral infection, more recent methods rely on approaches involving transgenesis and genome editing. These technologies allowed the identification of minor neural crest-derived cell populations in tissues of non-neural crest origin. Furthermore, in vivo multipotency at the single cell level and stage-dependent fate acquisitions were demonstrated using genetic technologies. Finally, recent reports indicate that neural crest-derived cells become activated in response to injury to secrete factors supporting tissue repair. Thus, neural crest-derived cells apparently contribute to tissue formation and regeneration by cell autonomous and non-autonomous mechanisms.


Assuntos
Linhagem da Célula/fisiologia , Desenvolvimento Embrionário/fisiologia , Crista Neural/citologia , Animais , Diferenciação Celular/fisiologia , Humanos
19.
Sci Transl Med ; 8(367): 367ra166, 2016 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-27903862

RESUMO

Interleukin-2 (IL-2) immunotherapy is an attractive approach in treating advanced cancer. However, by binding to its IL-2 receptor α (CD25) subunit, IL-2 exerts unwanted effects, including stimulation of immunosuppressive regulatory T cells (Tregs) and contribution to vascular leak syndrome. We used a rational approach to develop a monoclonal antibody to human IL-2, termed NARA1, which acts as a high-affinity CD25 mimic, thereby minimizing association of IL-2 with CD25. The structure of the IL-2-NARA1 complex revealed that NARA1 occupies the CD25 epitope of IL-2 and precisely overlaps with CD25. Association of NARA1 with IL-2 occurs with 10-fold higher affinity compared to CD25 and forms IL-2/NARA1 complexes, which, in vivo, preferentially stimulate CD8+ T cells while disfavoring CD25+ Tregs and improving the benefit-to-adverse effect ratio of IL-2. In two transplantable and one spontaneous metastatic melanoma model, IL-2/NARA1 complex immunotherapy resulted in efficient expansion of tumor-specific and polyclonal CD8+ T cells. These CD8+ T cells showed robust interferon-γ production and expressed low levels of exhaustion markers programmed cell death protein-1, lymphocyte activation gene-3, and T cell immunoglobulin and mucin domain-3. These effects resulted in potent anticancer immune responses and prolonged survival in the tumor models. Collectively, our data demonstrate that NARA1 acts as a CD25-mimobody that confers selectivity and increased potency to IL-2 and warrant further assessment of NARA1 as a therapeutic.


Assuntos
Anticorpos Monoclonais/química , Imunoterapia/métodos , Subunidade alfa de Receptor de Interleucina-2/imunologia , Interleucina-2/antagonistas & inibidores , Neoplasias/terapia , Animais , Sítios de Ligação , Linfócitos T CD8-Positivos/citologia , Proliferação de Células , Epitopos/química , Inativação Gênica , Humanos , Melanoma Experimental/imunologia , Melanoma Experimental/terapia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neoplasias/imunologia , Conformação Proteica , Recombinação Genética , Linfócitos T Citotóxicos/citologia , Linfócitos T Reguladores/imunologia
20.
Methods Mol Biol ; 2015 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-26659800

RESUMO

During development, melanocyte progenitors originate from the neural crest, a transient embryonic structure in vertebrates that gives rise to a variety of cell types including neurons and glia of the peripheral nervous system, smooth muscle cells of the cardiovascular system, chondrocytes and osteoblasts of the craniofacial elements, and pigment cells in the skin. In this chapter, we describe a method for the differentiation of multipotent embryonic neural crest stem cells into differentiated pigmented melanocytes by using in vitro explant culture system. This protocol allows the dissection of genetic and cellular mechanisms regulating neural crest stem cell and melanocyte development. Based on this knowledge it is possible to make predictions about processes that might also be implicated in melanoma initiation and progression.

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