Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
1.
Cell ; 177(5): 1172-1186.e14, 2019 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-31031009

RESUMO

Our bodies are equipped with powerful immune surveillance to clear cancerous cells as they emerge. How tumor-initiating stem cells (tSCs) that form and propagate cancers equip themselves to overcome this barrier remains poorly understood. To tackle this problem, we designed a skin cancer model for squamous cell carcinoma (SCC) that can be effectively challenged by adoptive cytotoxic T cell transfer (ACT)-based immunotherapy. Using single-cell RNA sequencing (RNA-seq) and lineage tracing, we found that transforming growth factor ß (TGF-ß)-responding tSCs are superior at resisting ACT and form the root of tumor relapse. Probing mechanism, we discovered that during malignancy, tSCs selectively acquire CD80, a surface ligand previously identified on immune cells. Moreover, upon engaging cytotoxic T lymphocyte antigen-4 (CTLA4), CD80-expressing tSCs directly dampen cytotoxic T cell activity. Conversely, upon CTLA4- or TGF-ß-blocking immunotherapies or Cd80 ablation, tSCs become vulnerable, diminishing tumor relapse after ACT treatment. Our findings place tSCs at the crux of how immune checkpoint pathways are activated.


Assuntos
Transferência Adotiva , Carcinoma de Células Escamosas/imunologia , Imunidade Celular , Vigilância Imunológica , Células-Tronco Neoplásicas/imunologia , Neoplasias Cutâneas/imunologia , Linfócitos T/imunologia , Animais , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Transgênicos , Proteínas de Neoplasias/imunologia , Células-Tronco Neoplásicas/patologia , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/terapia , Linfócitos T/patologia
2.
Cell ; 169(3): 483-496.e13, 2017 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-28413068

RESUMO

Adult tissue stem cells (SCs) reside in niches, which, through intercellular contacts and signaling, influence SC behavior. Once activated, SCs typically give rise to short-lived transit-amplifying cells (TACs), which then progress to differentiate into their lineages. Here, using single-cell RNA-seq, we unearth unexpected heterogeneity among SCs and TACs of hair follicles. We trace the roots of this heterogeneity to micro-niches along epithelial-mesenchymal interfaces, where progenitors display molecular signatures reflective of spatially distinct local signals and intercellular interactions. Using lineage tracing, temporal single-cell analyses, and chromatin landscaping, we show that SC plasticity becomes restricted in a sequentially and spatially choreographed program, culminating in seven spatially arranged unilineage progenitors within TACs of mature follicles. By compartmentalizing SCs into micro-niches, tissues gain precise control over morphogenesis and regeneration: some progenitors specify lineages immediately, whereas others retain potency, preserving self-renewing features established early while progressively restricting lineages as they experience dynamic changes in microenvironment.


Assuntos
Células-Tronco Adultas/citologia , Linhagem da Célula , Folículo Piloso/citologia , Nicho de Células-Tronco , Animais , Proteínas Morfogenéticas Ósseas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Análise de Sequência de RNA , Análise de Célula Única , Via de Sinalização Wnt
3.
Cell ; 169(4): 636-650.e14, 2017 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-28434617

RESUMO

Tissue stem cells contribute to tissue regeneration and wound repair through cellular programs that can be hijacked by cancer cells. Here, we investigate such a phenomenon in skin, where during homeostasis, stem cells of the epidermis and hair follicle fuel their respective tissues. We find that breakdown of stem cell lineage confinement-granting privileges associated with both fates-is not only hallmark but also functional in cancer development. We show that lineage plasticity is critical in wound repair, where it operates transiently to redirect fates. Investigating mechanism, we discover that irrespective of cellular origin, lineage infidelity occurs in wounding when stress-responsive enhancers become activated and override homeostatic enhancers that govern lineage specificity. In cancer, stress-responsive transcription factor levels rise, causing lineage commanders to reach excess. When lineage and stress factors collaborate, they activate oncogenic enhancers that distinguish cancers from wounds.


Assuntos
Carcinoma de Células Escamosas/patologia , Linhagem da Célula , Células Epidérmicas , Folículo Piloso/citologia , Neoplasias Cutâneas/patologia , Pele/citologia , Células-Tronco/metabolismo , Animais , Linhagem Celular Tumoral , Cromatina/metabolismo , Epiderme/metabolismo , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neoplasias Cutâneas/metabolismo , Fatores de Transcrição/metabolismo , Transcriptoma , Transplante Heterólogo , Cicatrização
4.
Nature ; 612(7940): 555-563, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36450983

RESUMO

Squamous cell carcinomas are triggered by marked elevation of RAS-MAPK signalling and progression from benign papilloma to invasive malignancy1-4. At tumour-stromal interfaces, a subset of tumour-initiating progenitors, the cancer stem cells, obtain increased resistance to chemotherapy and immunotherapy along this pathway5,6. The distribution and changes in cancer stem cells during progression from a benign state to invasive squamous cell carcinoma remain unclear. Here we show in mice that, after oncogenic RAS activation, cancer stem cells rewire their gene expression program and trigger self-propelling, aberrant signalling crosstalk with their tissue microenvironment that drives their malignant progression. The non-genetic, dynamic cascade of intercellular exchanges involves downstream pathways that are often mutated in advanced metastatic squamous cell carcinomas with high mutational burden7. Coupling our clonal skin HRASG12V mouse model with single-cell transcriptomics, chromatin landscaping, lentiviral reporters and lineage tracing, we show that aberrant crosstalk between cancer stem cells and their microenvironment triggers angiogenesis and TGFß signalling, creating conditions that are conducive for hijacking leptin and leptin receptor signalling, which in turn launches downstream phosphoinositide 3-kinase (PI3K)-AKT-mTOR signalling during the benign-to-malignant transition. By functionally examining each step in this pathway, we reveal how dynamic temporal crosstalk with the microenvironment orchestrated by the stem cells profoundly fuels this path to malignancy. These insights suggest broad implications for cancer therapeutics.


Assuntos
Carcinoma de Células Escamosas , Genes ras , Células-Tronco Neoplásicas , Transdução de Sinais , Microambiente Tumoral , Proteínas ras , Animais , Camundongos , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Leptina/metabolismo , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Neovascularização Patológica , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas ras/genética , Proteínas ras/metabolismo , Fator de Crescimento Transformador beta/metabolismo
5.
J Allergy Clin Immunol ; 153(1): 132-145, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37783432

RESUMO

BACKGROUND: Basophils are rare but important effector cells in many allergic disorders. Contrary to their early progenitors, the terminal developmental processes of basophils in which they gain their unique functional properties are unknown. OBJECTIVE: We sought to identify a novel late-stage basophil precursor and a transcription factor regulating the terminal maturation of basophils. METHODS: Using flow cytometry, transcriptome analysis, and functional assays, we investigated the identification and functionality of the basophil precursors as well as basophil development. We generated mice with basophil-specific deletion of nuclear factor IL-3 (NFIL3)/E4BP4 and analyzed the functional impairment of NFIL3/E4BP4-deficient basophils in vitro and in vivo using an oxazolone-induced murine model of allergic dermatitis. RESULTS: We report a new mitotic transitional basophil precursor population (referred to as transitional basophils) that expresses the FcεRIα chain at higher levels than mature basophils. Transitional basophils are less responsive to IgE-linked degranulation but produce more cytokines in response to IL-3, IL-33, or IgE cross-linking than mature basophils. In particular, we found that the expression of NFIL3/E4BP4 gradually rises as cells mature from the basophil progenitor stage. Basophil-specific deletion of NFIL3/E4BP4 reduces the expression of genes necessary for basophil function and impairs IgE receptor signaling, cytokine secretion, and degranulation in the context of murine atopic dermatitis. CONCLUSIONS: We discovered transitional basophils, a novel late-stage mitotic basophil precursor cell population that exists between basophil progenitors and postmitotic mature basophils. We demonstrated that NFIL3/E4BP4 augments the IgE-mediated functions of basophils, pointing to a potential therapeutic regulator for allergic diseases.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica , Basófilos , Animais , Camundongos , Basófilos/citologia , Basófilos/metabolismo , Dermatite Atópica/metabolismo , Hipersensibilidade/metabolismo , Imunoglobulina E/metabolismo , Interleucina-3/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo
6.
Exp Dermatol ; 33(1): e14844, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37264692

RESUMO

Alopecia areata (AA) is a T-cell-mediated autoimmune disease that causes chronic, relapsing hair loss; however, its precise pathogenesis remains to be elucidated. Recent studies have provided compelling evidence of crosstalk between inflammasomes and mitophagy-a process that contributes to the removal of damaged mitochondria. Our previous studies showed that the NLR family pyrin domain containing 3 (NLRP3) inflammasome is important for eliciting and progressing inflammation in AA. In this study, we detected mitochondrial DNA damage in AA-affected scalp tissues and IFNγ and poly(I:C) treated outer root sheath (ORS) cells. In addition, IFNγ and poly(I:C) treatment increased mitochondrial reactive oxygen species (ROS) levels in ORS cells. Moreover, we showed that mitophagy induction alleviates IFNγ and poly(I:C)-induced NLRP3 inflammasome activation in ORS cells. Lastly, PTEN-induced kinase 1 (PINK1) knockdown increased NLRP3 inflammasome activation, indicating that PINK1-mediated mitophagy plays a critical role in NLRP3 inflammasome activation in ORS cells. This study supports previous studies showing that oxidative stress disrupts immune privilege status and promotes autoimmunity in AA. The results emphasize the significance of crosstalk between mitophagy and inflammasomes in the pathogenesis of AA. Finally, mitophagy factors regulating mitochondrial dysfunction and inhibiting inflammasome activation could be novel therapeutic targets for AA.


Assuntos
Alopecia em Áreas , Inflamassomos , Humanos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Mitofagia/fisiologia , Espécies Reativas de Oxigênio , Proteínas Quinases , PTEN Fosfo-Hidrolase
7.
Proc Natl Acad Sci U S A ; 117(10): 5339-5350, 2020 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-32094197

RESUMO

Aging manifests with architectural alteration and functional decline of multiple organs throughout an organism. In mammals, aged skin is accompanied by a marked reduction in hair cycling and appearance of bald patches, leading researchers to propose that hair follicle stem cells (HFSCs) are either lost, differentiate, or change to an epidermal fate during aging. Here, we employed single-cell RNA-sequencing to interrogate aging-related changes in the HFSCs. Surprisingly, although numbers declined, aging HFSCs were present, maintained their identity, and showed no overt signs of shifting to an epidermal fate. However, they did exhibit prevalent transcriptional changes particularly in extracellular matrix genes, and this was accompanied by profound structural perturbations in the aging SC niche. Moreover, marked age-related changes occurred in many nonepithelial cell types, including resident immune cells, sensory neurons, and arrector pili muscles. Each of these SC niche components has been shown to influence HF regeneration. When we performed skin injuries that are known to mobilize young HFSCs to exit their niche and regenerate HFs, we discovered that aged skin is defective at doing so. Interestingly, however, in transplantation assays in vivo, aged HFSCs regenerated HFs when supported with young dermis, while young HFSCs failed to regenerate HFs when combined with aged dermis. Together, our findings highlight the importance of SC:niche interactions and favor a model where youthfulness of the niche microenvironment plays a dominant role in dictating the properties of its SCs and tissue health and fitness.


Assuntos
Folículo Piloso/fisiologia , Regeneração/fisiologia , Envelhecimento da Pele/fisiologia , Nicho de Células-Tronco/fisiologia , Células-Tronco/fisiologia , Animais , Derme/fisiologia , Células Epidérmicas/fisiologia , Epiderme/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Músculos/fisiologia , Reepitelização , Regeneração/genética , Células Receptoras Sensoriais/fisiologia , Envelhecimento da Pele/genética , Nicho de Células-Tronco/genética , Transplante de Células-Tronco , Transcriptoma , Cicatrização/genética , Cicatrização/fisiologia
8.
Nature ; 521(7552): 366-70, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25799994

RESUMO

Adult stem cells occur in niches that balance self-renewal with lineage selection and progression during tissue homeostasis. Following injury, culture or transplantation, stem cells outside their niche often display fate flexibility. Here we show that super-enhancers underlie the identity, lineage commitment and plasticity of adult stem cells in vivo. Using hair follicle as a model, we map the global chromatin domains of hair follicle stem cells and their committed progenitors in their native microenvironments. We show that super-enhancers and their dense clusters ('epicentres') of transcription factor binding sites undergo remodelling upon lineage progression. New fate is acquired by decommissioning old and establishing new super-enhancers and/or epicentres, an auto-regulatory process that abates one master regulator subset while enhancing another. We further show that when outside their niche, either in vitro or in wound-repair, hair follicle stem cells dynamically remodel super-enhancers in response to changes in their microenvironment. Intriguingly, some key super-enhancers shift epicentres, enabling their genes to remain active and maintain a transitional state in an ever-changing transcriptional landscape. Finally, we identify SOX9 as a crucial chromatin rheostat of hair follicle stem cell super-enhancers, and provide functional evidence that super-enhancers are dynamic, dense transcription-factor-binding platforms which are acutely sensitive to pioneer master regulators whose levels define not only spatial and temporal features of lineage-status but also stemness, plasticity in transitional states and differentiation.


Assuntos
Adaptação Fisiológica , Células-Tronco Adultas/citologia , Diferenciação Celular/genética , Linhagem da Célula/genética , Elementos Facilitadores Genéticos/genética , Folículo Piloso/citologia , Fatores de Transcrição SOX9/metabolismo , Células-Tronco Adultas/metabolismo , Animais , Sequência de Bases , Cromatina/genética , Cromatina/metabolismo , Feminino , Camundongos , Especificidade de Órgãos , Nicho de Células-Tronco , Fatores de Tempo
9.
Circ Res ; 115(2): 215-26, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-24755984

RESUMO

RATIONALE: The Notch pathway stabilizes sprouting angiogenesis by favoring stalk cells over tip cells at the vascular front. Because tip and stalk cells have different properties in morphology and function, their transcriptional regulation remains to be distinguished. Transcription factor Sox17 is specifically expressed in endothelial cells, but its expression and role at the vascular front remain largely unknown. OBJECTIVE: To specify the role of Sox17 and its relationship with the Notch pathway in sprouting angiogenesis. METHODS AND RESULTS: Endothelial-specific Sox17 deletion reduces sprouting angiogenesis in mouse embryonic and postnatal vascular development, whereas Sox17 overexpression increases it. Sox17 promotes endothelial migration by destabilizing endothelial junctions and rearranging cytoskeletal structure and upregulates expression of several genes preferentially expressed in tip cells. Interestingly, Sox17 expression is suppressed in stalk cells in which Notch signaling is relatively high. Notch activation by overexpressing Notch intracellular domain reduces Sox17 expression both in primary endothelial cells and in retinal angiogenesis, whereas Notch inhibition by delta-like ligand 4 (Dll4) blockade increases it. The Notch pathway regulates Sox17 expression mainly at the post-transcriptional level. Furthermore, endothelial Sox17 ablation rescues vascular network from excessive tip cell formation and hyperbranching under Notch inhibition in developmental and tumor angiogenesis. CONCLUSIONS: Our findings demonstrate that the Notch pathway restricts sprouting angiogenesis by reducing the expression of proangiogenic regulator Sox17.


Assuntos
Células Endoteliais/metabolismo , Proteínas HMGB/fisiologia , Neovascularização Patológica/fisiopatologia , Neovascularização Fisiológica/fisiologia , Receptores Notch/fisiologia , Fatores de Transcrição SOXF/fisiologia , Transdução de Sinais/fisiologia , Animais , Carcinoma Pulmonar de Lewis/irrigação sanguínea , Diferenciação Celular , Movimento Celular , Citoesqueleto/ultraestrutura , Embrião de Mamíferos/irrigação sanguínea , Células-Tronco Embrionárias , Regulação da Expressão Gênica , Proteínas HMGB/biossíntese , Proteínas HMGB/genética , Células Endoteliais da Veia Umbilical Humana , Humanos , Junções Intercelulares/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Morfogênese/genética , Estrutura Terciária de Proteína , RNA Interferente Pequeno/farmacologia , Receptor Notch1/genética , Receptor Notch1/fisiologia , Proteínas Recombinantes de Fusão , Vasos Retinianos/crescimento & desenvolvimento , Fatores de Transcrição SOXF/biossíntese , Fatores de Transcrição SOXF/genética , Organismos Livres de Patógenos Específicos , Transcrição Gênica
10.
Biol Psychiatry ; 93(9): 829-841, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36759256

RESUMO

BACKGROUND: In tauopathies, brain regions with tau accumulation strongly correlate with clinical symptoms, and spreading of misfolded tau along neural network leads to disease progression. However, the underlying mechanisms by which tau proteins enter neurons during pathological propagation remain unclear. METHODS: To identify membrane receptors responsible for neuronal propagation of tau oligomers, we established a cell-based tau uptake assay and screened complementary DNA expression library. Tau uptake and propagation were analyzed in vitro and in vivo using a microfluidic device and stereotactic injection. The cognitive function of mice was assessed using behavioral tests. RESULTS: From a genome-wide cell-based functional screening, RAGE (receptor for advanced glycation end products) was isolated to stimulate the cellular uptake of tau oligomers. Rage deficiency reduced neuronal uptake of pathological tau prepared from rTg4510 mouse brains or cerebrospinal fluid from patients with Alzheimer's disease and slowed tau propagation between neurons cultured in a 3-chamber microfluidic device. RAGE levels were increased in the brains of rTg4510 mice and tau oligomer-treated neurons. Rage knockout decreased tau transmission in the brains of nontransgenic mice after injection with Alzheimer's disease patient-derived tau and ameliorated memory loss after injection with GFP-P301L-tau-AAV. Treatment of RAGE antagonist FPS-ZM1 blocked transsynaptic tau propagation and inflammatory responses and alleviated cognitive impairment in rTg4510 mice. CONCLUSIONS: These results suggest that in neurons and microglia, RAGE binds to pathological tau and facilitates neuronal tau pathology progression and behavioral deficits in tauopathies.


Assuntos
Doença de Alzheimer , Receptor para Produtos Finais de Glicação Avançada , Tauopatias , Proteínas tau , Animais , Camundongos , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Modelos Animais de Doenças , Transtornos da Memória/metabolismo , Camundongos Transgênicos , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Proteínas tau/metabolismo , Tauopatias/metabolismo
11.
Cell Mol Gastroenterol Hepatol ; 14(6): 1235-1256, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35988719

RESUMO

BACKGROUND & AIMS: Inositol polyphosphate multikinase (IPMK), an essential enzyme for inositol phosphate metabolism, has been known to mediate major biological events such as growth. Recent studies have identified single-nucleotide polymorphisms in the IPMK gene associated with inflammatory bowel disease predisposition. Therefore, we aimed to investigate the functional significance of IPMK in gut epithelium. METHODS: We generated intestinal epithelial cell (IEC)-specific Ipmk knockout (IPMKΔIEC) mice, and assessed their vulnerability against dextran sulfate sodium-induced experimental colitis. Both bulk and single-cell RNA sequencing were performed to analyze IPMK-deficient colonic epithelial cells and colonic tuft cells. RESULTS: Although IPMKΔIEC mice developed normally and showed no intestinal abnormalities during homeostasis, Ipmk deletion aggravated dextran sulfate sodium-induced colitis, with higher clinical colitis scores, and increased epithelial barrier permeability. Surprisingly, Ipmk deletion led to a significant decrease in the number of tuft cells without influencing other IECs. Single-cell RNA sequencing of mouse colonic tuft cells showed 3 distinct populations of tuft cells, and further showed that a transcriptionally inactive population was expanded markedly in IPMKΔIEC mice, while neuronal-related cells were relatively decreased. CONCLUSIONS: Cholinergic output from tuft cells is known to be critical for the restoration of intestinal architecture upon damage, supporting that tuft cell-defective IPMKΔIEC mice are more prone to colitis. Thus, intestinal epithelial IPMK is a critical regulator of colonic integrity and tissue regeneration by determining tuft cell homeostasis and affecting cholinergic output.


Assuntos
Colite , Camundongos , Animais , Sulfato de Dextrana , Colite/induzido quimicamente , Colite/tratamento farmacológico , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Homeostase
12.
Mol Cancer ; 10: 36, 2011 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-21481239

RESUMO

BACKGROUND: Most bladder cancer patients experience lymphatic metastasis in the course of disease progression, yet the relationship between lymphangiogenesis and lymphatic metastasis is not well known. The aim of this study is to elucidate underlying mechanisms of how expanded lymphatic vessels and tumor microenvironment interacts each other and to find effective therapeutic options to inhibit lymphatic metastasis. RESULTS: The orthotopic urinary bladder cancer (OUBC) model was generated by intravesical injection of MBT-2 cell lines. We investigated the angiogenesis, lymphangiogenesis, and CD11b+/CD68+ tumor-associated macrophages (TAM) by using immunofluorescence staining. OUBC displayed a profound lymphangiogenesis and massive infiltration of TAM in primary tumor and lymphatic metastasis in lymph nodes. TAM flocked near lymphatic vessels and express higher levels of VEGF-C/D than CD11b- cells. Because VEGFR-3 was highly expressed in lymphatic vascular endothelial cells, TAM could assist lymphangiogenesis by paracrine manner in bladder tumor. VEGFR-3 expressing adenovirus was administered to block VEGF-C/D signaling pathway and clodronate liposome was used to deplete TAM. The blockade of VEGF-C/D with soluble VEGF receptor-3 markedly inhibited lymphangiogenesis and lymphatic metastasis in OUBC. In addition, the depletion of TAM with clodronate liposome exerted similar effects on OUBC. CONCLUSION: VEGF-C/D are the main factors of lymphangiogenesis and lymphatic metastasis in bladder cancer. Moreover, TAM plays an important role in these processes by producing VEGF-C/D. The inhibition of lymphangiogenesis could provide another therapeutic target to inhibit lymphatic metastasis and recurrence in patients with invasive bladder cancer.


Assuntos
Linfangiogênese , Macrófagos/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/genética , Antígenos de Diferenciação Mielomonocítica/metabolismo , Antígeno CD11b/genética , Antígeno CD11b/metabolismo , Linhagem Celular Tumoral , Feminino , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica , Imuno-Histoquímica , Linfonodos/metabolismo , Linfonodos/patologia , Metástase Linfática , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C3H , Neovascularização Patológica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Solubilidade , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Fator C de Crescimento do Endotélio Vascular/genética , Fator C de Crescimento do Endotélio Vascular/metabolismo , Fator D de Crescimento do Endotélio Vascular/genética , Fator D de Crescimento do Endotélio Vascular/metabolismo , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/genética
13.
Blood ; 113(22): 5650-9, 2009 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-19346498

RESUMO

Using a bacterial pathogen-induced acute inflammation model in the skin, we defined the roles of local lymphatic vessels and draining lymph nodes (DLNs) in antigen clearance and inflammation resolution. At the peak day of inflammation, robust expansion of lymphatic vessels and profound infiltration of CD11b+/Gr-1+ macrophages into the inflamed skin and DLN were observed. Moreover, lymph flow and inflammatory cell migration from the inflamed skin to DLNs were enhanced. Concomitantly, the expression of lymphangiogenic growth factors such as vascular endothelial growth factor C (VEGF-C), VEGF-D, and VEGF-A were significantly up-regulated in the inflamed skin, DLNs, and particularly in enriched CD11b+ macrophages from the DLNs. Depletion of macrophages, or blockade of VEGF-C/D or VEGF-A, largely attenuated these phenomena, and produced notably delayed antigen clearance and inflammation resolution. Conversely, keratin 14 (K14)-VEGF-C transgenic mice, which have dense and enlarged lymphatic vessels in the skin dermis, exhibited accelerated migration of inflammatory cells from the inflamed skin to the DLNs and faster antigen clearance and inflammation resolution. Taken together, these results indicate that VEGF-C, -D, and -A derived from the CD11b+/Gr-1+ macrophages and local inflamed tissues play a critical role in promoting antigen clearance and inflammation resolution.


Assuntos
Antígenos/metabolismo , Antígeno CD11b/metabolismo , Doenças Linfáticas/imunologia , Vasos Linfáticos/patologia , Macrófagos/fisiologia , Fator A de Crescimento do Endotélio Vascular/fisiologia , Animais , Antígenos/imunologia , Antígeno CD11b/fisiologia , Dermatite/imunologia , Dermatite/metabolismo , Dermatite/patologia , Inflamação/induzido quimicamente , Inflamação/imunologia , Inflamação/patologia , Lipopolissacarídeos/farmacologia , Linfangiogênese/imunologia , Linfangiogênese/fisiologia , Doenças Linfáticas/induzido quimicamente , Vasos Linfáticos/fisiologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores de Quimiocinas/metabolismo
14.
Commun Biol ; 4(1): 692, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099859

RESUMO

Research on human nail tissue has been limited by the restricted access to fresh specimen. Here, we studied transcriptome profiles of human nail units using polydactyly specimens. Single-cell RNAseq with 11,541 cells from 4 extra digits revealed nail-specific mesenchymal and epithelial cell populations, characterized by RSPO4 (major gene in congenital anonychia) and SPINK6, respectively. In situ RNA hybridization demonstrated the localization of RSPO4, MSX1 and WIF1 in onychofibroblasts suggesting the activation of WNT signaling. BMP-5 was also expressed in onychofibroblasts implicating the contribution of BMP signaling. SPINK6 expression distinguished the nail-specific keratinocytes from epidermal keratinocytes. RSPO4+ onychofibroblasts were distributed at close proximity with LGR6+ nail matrix, leading to WNT/ß-catenin activation. In addition, we demonstrated RSPO4 was overexpressed in the fibroblasts of onychomatricoma and LGR6 was highly expressed at the basal layer of the overlying epithelial component, suggesting that onychofibroblasts may play an important role in the pathogenesis of onychomatricoma.


Assuntos
Unhas/citologia , Inibidores de Serinopeptidase do Tipo Kazal/genética , Trombospondinas/genética , Células Cultivadas , Fibroblastos/citologia , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Queratinócitos/patologia , Unhas/metabolismo , Unhas/patologia , Análise de Sequência de RNA , Análise de Célula Única , Transcriptoma
15.
Nat Cell Biol ; 22(6): 640-650, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32393888

RESUMO

Tissue homeostasis and regeneration rely on resident stem cells (SCs), whose behaviour is regulated through niche-dependent crosstalk. The mechanisms underlying SC identity are still unfolding. Here, using spatiotemporal gene ablation in murine hair follicles, we uncover a critical role for the transcription factors (TFs) nuclear factor IB (NFIB) and IX (NFIX) in maintaining SC identity. Without NFI TFs, SCs lose their hair-regenerating capability, and produce skin bearing striking resemblance to irreversible human alopecia, which also displays reduced NFIs. Through single-cell transcriptomics, ATAC-Seq and ChIP-Seq profiling, we expose a key role for NFIB and NFIX in governing super-enhancer maintenance of the key hair follicle SC-specific TF genes. When NFIB and NFIX are genetically removed, the stemness epigenetic landscape is lost. Super-enhancers driving SC identity are decommissioned, while unwanted lineages are de-repressed ectopically. Together, our findings expose NFIB and NFIX as crucial rheostats of tissue homeostasis, functioning to safeguard the SC epigenome from a breach in lineage confinement that otherwise triggers irreversible tissue degeneration.


Assuntos
Alopecia/patologia , Diferenciação Celular , Cromatina/metabolismo , Folículo Piloso/citologia , Fatores de Transcrição NFI/fisiologia , Células-Tronco/citologia , Alopecia/genética , Alopecia/metabolismo , Animais , Células Cultivadas , Cromatina/genética , Feminino , Folículo Piloso/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Regeneração , Células-Tronco/metabolismo
16.
Science ; 366(6470): 1218-1225, 2019 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-31672914

RESUMO

Tissues rely on stem cells (SCs) for homeostasis and wound repair. SCs reside in specialized microenvironments (niches) whose complexities and roles in orchestrating tissue growth are still unfolding. Here, we identify lymphatic capillaries as critical SC-niche components. In skin, lymphatics form intimate networks around hair follicle (HF) SCs. When HFs regenerate, lymphatic-SC connections become dynamic. Using a mouse model, we unravel a secretome switch in SCs that controls lymphatic behavior. Resting SCs express angiopoietin-like protein 7 (Angptl7), promoting lymphatic drainage. Activated SCs switch to Angptl4, triggering transient lymphatic dissociation and reduced drainage. When lymphatics are perturbed or the secretome switch is disrupted, HFs cycle precociously and tissue regeneration becomes asynchronous. In unearthing lymphatic capillaries as a critical SC-niche element, we have learned how SCs coordinate their activity across a tissue.


Assuntos
Folículo Piloso/fisiologia , Vasos Linfáticos/fisiologia , Regeneração , Nicho de Células-Tronco/fisiologia , Células-Tronco/fisiologia , Proteína 4 Semelhante a Angiopoietina/metabolismo , Proteína 7 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina/metabolismo , Animais , Proteínas de Homeodomínio/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Células-Tronco/metabolismo , Proteínas Supressoras de Tumor/genética
18.
Cell Stem Cell ; 22(3): 398-413.e7, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29337183

RESUMO

Tissue regeneration relies on resident stem cells (SCs), whose activity and lineage choices are influenced by the microenvironment. Exploiting the synchronized, cyclical bouts of tissue regeneration in hair follicles (HFs), we investigate how microenvironment dynamics shape the emergence of stem cell lineages. Employing epigenetic and ChIP-seq profiling, we uncover how signal-dependent transcription factors couple spatiotemporal cues to chromatin dynamics, thereby choreographing stem cell lineages. Using enhancer-driven reporters, mutagenesis, and genetics, we show that simultaneous BMP-inhibitory and WNT signals set the stage for lineage choices by establishing chromatin platforms permissive for diversification. Mechanistically, when binding of BMP effector pSMAD1 is relieved, enhancers driving HF-stem cell master regulators are silenced. Concomitantly, multipotent, lineage-fated enhancers silent in HF-stem cells become activated by exchanging WNT effectors TCF3/4 for LEF1. Throughout regeneration, lineage enhancers continue reliance upon LEF1 but then achieve specificity by accommodating additional incoming signaling effectors. Barriers to progenitor plasticity increase when diverse, signal-sensitive transcription factors shape LEF1-regulated enhancer dynamics.


Assuntos
Linhagem da Célula , Montagem e Desmontagem da Cromatina , Folículo Piloso/citologia , Transdução de Sinais , Células-Tronco/citologia , Células-Tronco/metabolismo , Acetilação , Animais , Sequência de Bases , Proteínas Morfogenéticas Ósseas/metabolismo , Cromatina/metabolismo , Elementos Facilitadores Genéticos/genética , Histonas/metabolismo , Lisina/metabolismo , Camundongos Endogâmicos C57BL , Fosforilação , Regeneração , Proteína Smad1/metabolismo , Fatores de Tempo , Fatores de Transcrição/metabolismo , Via de Sinalização Wnt
19.
Elife ; 4: e10870, 2015 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-26590320

RESUMO

Tumor-initiating stem cells (SCs) exhibit distinct patterns of transcription factors and gene expression compared to healthy counterparts. Here, we show that dramatic shifts in large open-chromatin domain (super-enhancer) landscapes underlie these differences and reflect tumor microenvironment. By in vivo super-enhancer and transcriptional profiling, we uncover a dynamic cancer-specific epigenetic network selectively enriched for binding motifs of a transcription factor cohort expressed in squamous cell carcinoma SCs (SCC-SCs). Many of their genes, including Ets2 and Elk3, are themselves regulated by SCC-SC super-enhancers suggesting a cooperative feed-forward loop. Malignant progression requires these genes, whose knockdown severely impairs tumor growth and prohibits progression from benign papillomas to SCCs. ETS2-deficiency disrupts the SCC-SC super-enhancer landscape and downstream cancer genes while ETS2-overactivation in epidermal-SCs induces hyperproliferation and SCC super-enhancer-associated genes Fos, Junb and Klf5. Together, our findings unearth an essential regulatory network required for the SCC-SC chromatin landscape and unveil its importance in malignant progression.


Assuntos
Carcinoma de Células Escamosas/patologia , Cromatina/metabolismo , Redes Reguladoras de Genes , Proliferação de Células , Epigênese Genética , Humanos
20.
Cancer Cell ; 25(1): 102-17, 2014 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-24434213

RESUMO

Current antiangiogenic therapy is limited by its cytostatic nature and systemic side effects. To address these limitations, we have unveiled the role of RhoJ, an endothelial-enriched Rho GTPase, during tumor progression. RhoJ blockade provides a double assault on tumor vessels by both inhibiting tumor angiogenesis and disrupting the preformed tumor vessels through the activation of the RhoA-ROCK (Rho kinase) signaling pathway in tumor endothelial cells, consequently resulting in a functional failure of tumor vasculatures. Moreover, enhanced anticancer effects were observed when RhoJ blockade was employed in concert with a cytotoxic chemotherapeutic agent, angiogenesis-inhibiting agent, or vascular-disrupting agent. These results identify RhoJ blockade as a selective and effective therapeutic strategy for targeting tumor vasculature with minimal side effects.


Assuntos
GTP Fosfo-Hidrolases/metabolismo , Neoplasias Experimentais/enzimologia , Neovascularização Patológica/enzimologia , Proteínas rho de Ligação ao GTP/metabolismo , Inibidores da Angiogênese/farmacologia , Animais , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neoplasias Experimentais/irrigação sanguínea , Neoplasias Experimentais/patologia , RNA Interferente Pequeno , Transdução de Sinais/efeitos dos fármacos , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa