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1.
Nat Commun ; 11(1): 5079, 2020 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-33033234

RESUMO

Tumor heterogeneity and lack of knowledge about resistant cell states remain a barrier to targeted cancer therapies. Basal cell carcinomas (BCCs) depend on Hedgehog (Hh)/Gli signaling, but can develop mechanisms of Smoothened (SMO) inhibitor resistance. We previously identified a nuclear myocardin-related transcription factor (nMRTF) resistance pathway that amplifies noncanonical Gli1 activity, but characteristics and drivers of the nMRTF cell state remain unknown. Here, we use single cell RNA-sequencing of patient tumors to identify three prognostic surface markers (LYPD3, TACSTD2, and LY6D) which correlate with nMRTF and resistance to SMO inhibitors. The nMRTF cell state resembles transit-amplifying cells of the hair follicle matrix, with AP-1 and TGFß cooperativity driving nMRTF activation. JNK/AP-1 signaling commissions chromatin accessibility and Smad3 DNA binding leading to a transcriptional program of RhoGEFs that facilitate nMRTF activity. Importantly, small molecule AP-1 inhibitors selectively target LYPD3+/TACSTD2+/LY6D+ nMRTF human BCCs ex vivo, opening an avenue for improving combinatorial therapies.


Assuntos
Carcinoma Basocelular/metabolismo , Proteínas Hedgehog/metabolismo , Transdução de Sinais , Neoplasias Cutâneas/metabolismo , Fator de Transcrição AP-1/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Cromatina/metabolismo , DNA de Neoplasias/metabolismo , Resistencia a Medicamentos Antineoplásicos , Matriz Extracelular/metabolismo , Ontologia Genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Folículo Piloso/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Proteínas de Neoplasias/metabolismo , Ligação Proteica , Proteína Smad3/metabolismo , Transativadores/metabolismo , Regulação para Cima
2.
Nat Commun ; 11(1): 4659, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938936

RESUMO

The αvß6 integrin plays a key role in the activation of transforming growth factor-ß (TGFß), a pro-fibrotic mediator that is pivotal to the development of idiopathic pulmonary fibrosis (IPF). We identified a selective small molecule αvß6 RGD-mimetic, GSK3008348, and profiled it in a range of disease relevant pre-clinical systems. To understand the relationship between target engagement and inhibition of fibrosis, we measured pharmacodynamic and disease-related end points. Here, we report, GSK3008348 binds to αvß6 with high affinity in human IPF lung and reduces downstream pro-fibrotic TGFß signaling to normal levels. In human lung epithelial cells, GSK3008348 induces rapid internalization and lysosomal degradation of the αvß6 integrin. In the murine bleomycin-induced lung fibrosis model, GSK3008348 engages αvß6, induces prolonged inhibition of TGFß signaling and reduces lung collagen deposition and serum C3M, a marker of IPF disease progression. These studies highlight the potential of inhaled GSK3008348 as an anti-fibrotic therapy.


Assuntos
Butiratos/farmacologia , Fibrose Pulmonar Idiopática/tratamento farmacológico , Integrinas/antagonistas & inibidores , Naftiridinas/farmacologia , Pirazóis/farmacologia , Pirrolidinas/farmacologia , Administração por Inalação , Animais , Antígenos de Neoplasias/metabolismo , Bleomicina/toxicidade , Butiratos/administração & dosagem , Butiratos/metabolismo , Butiratos/farmacocinética , Colágeno/metabolismo , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Humanos , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/patologia , Integrinas/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Naftiridinas/administração & dosagem , Naftiridinas/metabolismo , Naftiridinas/farmacocinética , Pirazóis/administração & dosagem , Pirazóis/metabolismo , Pirazóis/farmacocinética , Pirrolidinas/administração & dosagem , Pirrolidinas/metabolismo , Pirrolidinas/farmacocinética , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Tomografia Computadorizada de Emissão de Fóton Único , Fator de Crescimento Transformador beta/metabolismo , Pesquisa Médica Translacional
3.
PLoS Biol ; 18(9): e3000825, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32886690

RESUMO

Microbial dysbiosis in the upper digestive tract is linked to an increased risk of esophageal squamous cell carcinoma (ESCC). Overabundance of Porphyromonas gingivalis is associated with shorter survival of ESCC patients. We investigated the molecular mechanisms driving aggressive progression of ESCC by P. gingivalis. Intracellular invasion of P. gingivalis potentiated proliferation, migration, invasion, and metastasis abilities of ESCC cells via transforming growth factor-ß (TGFß)-dependent Drosophila mothers against decapentaplegic homologs (Smads)/Yes-associated protein (YAP)/Transcriptional coactivator with PDZ-binding motif (TAZ) activation. Smads/YAP/TAZ/TEA domain transcription factor1 (TEAD1) complex formation was essential to initiate downstream target gene expression, inducing an epithelial-mesenchymal transition (EMT) and stemness features. Furthermore, P. gingivalis augmented secretion and bioactivity of TGFß through glycoprotein A repetitions predominant (GARP) up-regulation. Accordingly, disruption of either the GARP/TGFß axis or its activated Smads/YAP/TAZ complex abrogated the tumor-promoting role of P. gingivalis. P. gingivalis signature genes based on its activated effector molecules can efficiently distinguish ESCC patients into low- and high-risk groups. Targeting P. gingivalis or its activated effectors may provide novel insights into clinical management of ESCC.


Assuntos
Infecções por Bacteroidaceae/complicações , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Porphyromonas gingivalis/fisiologia , Fator de Crescimento Transformador beta/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Idoso , Animais , Infecções por Bacteroidaceae/metabolismo , Infecções por Bacteroidaceae/mortalidade , Infecções por Bacteroidaceae/patologia , Células Cultivadas , Progressão da Doença , Drosophila , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/microbiologia , Neoplasias Esofágicas/mortalidade , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/microbiologia , Carcinoma de Células Escamosas do Esôfago/mortalidade , Feminino , Seguimentos , Células HCT116 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Transdução de Sinais/fisiologia , Proteínas Smad/metabolismo , Análise de Sobrevida , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo
4.
Life Sci ; 258: 118178, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32739468

RESUMO

AIMS: Gentamicin (GEN) is one of the most valuable aminoglycoside antibiotics utilized against life-threatening bacterial infections. Unfortunately, GEN-induced nephrotoxicity limited its clinical utility. The pathologic process of nephrotoxicity caused by GEN may involve epithelial to mesenchymal transition (EMT). Resveratrol (RES) is a natural compound was revealed to inhibit EMT in kidney. The present work was conducted to explore the potential renoprotective role of RES on GEN-induced EMT. Moreover, the underlying signaling pathway of this inhibition was investigated. MAIN METHODS: Mice were treated with GEN by intraperitoneal (i.p.) route daily for 15 days to identify EMT onset with regard to GEN-induced nephrotoxicity. To assess the ameliorative role of RES against GEN-induced EMT, RES was i.p. administrated in high and low doses before and concurrently with GEN treatment. KEY FINDINGS: GEN administration significantly deteriorated kidney functions. In addition, reduced glutathione (GSH) content and catalase (CAT) activity were significantly decreased with a concomitant increase in the content of kidney malondialdehyde (MDA) after GEN treatment. Histological changes and deposition of collagen were extensive in renal corpuscles and tubules. Increased expression of alpha smooth muscle actin (α-SMA), transforming growth factor-ß1 (TGF-ß1) and phosphorylated (p)-Smad2 were observed after GEN administration, while E-cadherin expression was decreased. On the contrary, pretreatment with both doses of RES reversed the modifications caused by GEN administration. SIGNIFICANCE: We concluded that EMT contributes to pathogenesis of GEN-induced nephrotoxicity. RES has a protective effect on GEN-induced EMT via suppressing oxidative stress and a possible involvement of TGF-ß/Smad signaling pathway.


Assuntos
Transição Epitelial-Mesenquimal/efeitos dos fármacos , Gentamicinas/efeitos adversos , Rim/metabolismo , Rim/patologia , Espécies Reativas de Oxigênio/metabolismo , Resveratrol/farmacologia , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Biomarcadores/sangue , Fibrose , Rim/efeitos dos fármacos , Rim/fisiopatologia , Masculino , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Resveratrol/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo
5.
Nature ; 585(7824): 283-287, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32814897

RESUMO

The risk of cancer and associated mortality increases substantially in humans from the age of 65 years onwards1-6. Nonetheless, our understanding of the complex relationship between age and cancer is still in its infancy2,3,7,8. For decades, this link has largely been attributed to increased exposure time to mutagens in older individuals. However, this view does not account for the established role of diet, exercise and small molecules that target the pace of metabolic ageing9-12. Here we show that metabolic alterations that occur with age can produce a systemic environment that favours the progression and aggressiveness of tumours. Specifically, we show that methylmalonic acid (MMA), a by-product of propionate metabolism, is upregulated in the serum of older people and functions as a mediator of tumour progression. We traced this to the ability of MMA to induce SOX4 expression and consequently to elicit transcriptional reprogramming that can endow cancer cells with aggressive properties. Thus, the accumulation of MMA represents a link between ageing and cancer progression, suggesting that MMA is a promising therapeutic target for advanced carcinomas.


Assuntos
Envelhecimento/metabolismo , Progressão da Doença , Ácido Metilmalônico/metabolismo , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias/patologia , Adulto , Idoso , Envelhecimento/sangue , Envelhecimento/genética , Animais , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Ácido Metilmalônico/sangue , Camundongos , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Metástase Neoplásica/genética , Metástase Neoplásica/patologia , Neoplasias/sangue , Neoplasias/genética , Fatores de Transcrição SOXC/metabolismo , Transdução de Sinais , Transcriptoma/genética , Fator de Crescimento Transformador beta/metabolismo
6.
PLoS Genet ; 16(8): e1008505, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32776934

RESUMO

Dynamic gene expression in neurons shapes fundamental processes in the nervous systems of animals. However, how neuronal activation by different stimuli can lead to distinct transcriptional responses is not well understood. We have been studying how microbial metabolites modulate gene expression in chemosensory neurons of Caenorhabditis elegans. Considering the diverse environmental stimuli that can activate chemosensory neurons of C. elegans, we sought to understand how specific transcriptional responses can be generated in these neurons in response to distinct cues. We have focused on the mechanism of rapid (<6 min) and selective transcriptional induction of daf-7, a gene encoding a TGF-ß ligand, in the ASJ chemosensory neurons in response to the pathogenic bacterium Pseudomonas aeruginosa. DAF-7 is required for the protective behavioral avoidance of P. aeruginosa by C. elegans. Here, we define the involvement of two distinct cyclic GMP (cGMP)-dependent pathways that are required for daf-7 expression in the ASJ neuron pair in response to P. aeruginosa. We show that a calcium-independent pathway dependent on the cGMP-dependent protein kinase G (PKG) EGL-4, and a canonical calcium-dependent signaling pathway dependent on the activity of a cyclic nucleotide-gated channel subunit CNG-2, function in parallel to activate rapid, selective transcription of daf-7 in response to P. aeruginosa metabolites. Our data suggest that fast, selective early transcription of neuronal genes require PKG in shaping responses to distinct microbial stimuli in a pair of C. elegans chemosensory neurons.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Células Quimiorreceptoras/metabolismo , GMP Cíclico/metabolismo , Pseudomonas aeruginosa/metabolismo , Fator de Crescimento Transformador beta/genética , Animais , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/metabolismo , Sinalização do Cálcio , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Canais de Cátion Regulados por Nucleotídeos Cíclicos/metabolismo , Ativação Transcricional , Fator de Crescimento Transformador beta/metabolismo
7.
Nat Commun ; 11(1): 3334, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620760

RESUMO

TH17 cells exemplify environmental immune adaptation: they can acquire both a pathogenic and an anti-inflammatory fate. However, it is not known whether the anti-inflammatory fate is merely a vestigial trait, or whether it serves to preserve the integrity of the host tissues. Here we show that the capacity of TH17 cells to acquire an anti-inflammatory fate is necessary to sustain immunological tolerance, yet it impairs immune protection against S. aureus. Additionally, we find that TGF-ß signalling via Smad3/Smad4 is sufficient for the expression of the anti-inflammatory cytokine, IL-10, in TH17 cells. Our data thus indicate a key function of TH17 cell plasticity in maintaining immune homeostasis, and dissect the molecular mechanisms explaining the functional flexibility of TH17 cells with regard to environmental changes.


Assuntos
Homeostase/imunologia , Inflamação/imunologia , Interleucina-10/imunologia , Intestinos/imunologia , Células Th17/imunologia , Animais , Plasticidade Celular/imunologia , Resistência à Doença/genética , Resistência à Doença/imunologia , Células HEK293 , Humanos , Interleucina-10/genética , Interleucina-10/metabolismo , Interleucina-17/genética , Interleucina-17/imunologia , Interleucina-17/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/imunologia , Staphylococcus aureus/fisiologia , Células Th17/metabolismo , Fator de Crescimento Transformador beta/imunologia , Fator de Crescimento Transformador beta/metabolismo
8.
Chem Biol Interact ; 329: 109210, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32726580

RESUMO

Cigarette smoke is a complex mixture capable of triggering inflammation and oxidative damage in animals at pulmonary and systemic levels. Tempol (4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl) reduces tissue injury associated with inflammation in vivo by mechanisms that are not completely understood. Here we evaluated the effect of tempol on inflammation and oxidative damage induced by acute exposure to cigarette smoke in vivo. Male C57BL/6 mice (n = 32) were divided into 4 groups (n = 8 each): 1) control group exposed to ambient air (GC), 2) animals exposed to cigarette smoke for 5 days (CSG), mice treated 3) prior or 4) concomitantly with tempol (50 mg/kg/day) and exposed to cigarette smoke for 5 days. The results showed that the total number of leukocytes and neutrophils increased in the respiratory tract and lung parenchyma of mice exposed to cigarette smoke. Likewise, MPO levels and activity as well as lipid peroxidation and lung protein nitration and carbonylation also increased. Administration of tempol before or during exposure to cigarette smoke inhibited all the above parameters. Tempol also reduced the pulmonary expression of the inflammatory cytokines Il-6, Il-1ß and Il-17 to basal levels and of Tnf-α by approximately 50%. In contrast, tempol restored Il-10 and Tgf-ß levels and enhanced the expression of Nrf2-associated genes, such as Ho-1 and Gpx2. Accordingly, total GPx activity increased in lung homogenates of tempol-treated animals. Taken together, our results show that tempol protects mouse lungs from inflammation and oxidative damage resulting from exposure to cigarette smoke, likely through reduction of leukocyte infiltration and increased transcription of some of the Nrf2-controlled genes.


Assuntos
Óxidos N-Cíclicos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Infiltração de Neutrófilos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fumar/efeitos adversos , Animais , Líquido da Lavagem Broncoalveolar/química , Interleucina-10/genética , Interleucina-10/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/genética , Nitritos/análise , Peroxidase/metabolismo , Carbonilação Proteica/efeitos dos fármacos , Marcadores de Spin , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo
9.
Proc Natl Acad Sci U S A ; 117(29): 17166-17176, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32632016

RESUMO

Signaling of 17ß-estradiol (estrogen) through its two nuclear receptors, α and ß (ERα, ERß), is an important mechanism of transcriptional regulation. Although ERs are broadly expressed by cells of the immune system, the mechanisms by which they modulate immune responses remain poorly understood. ERß-specific signaling is reduced in patients with chronic inflammatory diseases, including systemic lupus erythematosus and inflammatory bowel disease, and our previous work suggests that dysregulation of ERß-specific signaling contributes to enhanced intestinal inflammation in female SAMP/YitFC mice, a spontaneous model of Crohn's disease-like ileitis. The present study builds on these prior observations to identify a nonredundant, immunoprotective role for ERß-specific signaling in TGF-ß-dependent regulatory T cell (Treg) differentiation. Using a strain of congenic SAMP mice engineered to lack global expression of ERß, we observed dramatic, female-specific exacerbation of intestinal inflammation accompanied by significant reductions in intestinal Treg frequency and function. Impaired Treg suppression in the absence of ERß was associated with aberrant overexpression of Tsc22d3 (GILZ), a glucocorticoid-responsive transcription factor not normally expressed in mature Tregs, and ex vivo data reveal that forced overexpression of GILZ in mature Tregs inhibits their suppressive function. Collectively, our findings identify a pathway of estrogen-mediated immune regulation in the intestine, whereby homeostatic expression of ERß normally functions to limit Treg-specific expression of GILZ, thereby maintaining effective immune suppression. Our data suggest that transcriptional cross-talk between glucocorticoid and steroid sex hormone signaling represents an important and understudied regulatory node in chronic inflammatory disease.


Assuntos
Receptor beta de Estrogênio/metabolismo , Estrogênios/metabolismo , Inflamação/imunologia , Intestinos/imunologia , Transdução de Sinais/fisiologia , Linfócitos T Reguladores/imunologia , Adolescente , Adulto , Animais , Doença de Crohn/imunologia , Modelos Animais de Doenças , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/genética , Feminino , Glucocorticoides/metabolismo , Humanos , Ileíte/patologia , Doenças Inflamatórias Intestinais/imunologia , Intestinos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Adulto Jovem
10.
Science ; 369(6501)2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32675345

RESUMO

Targeting the cross-talk between tumor-initiating cells (TICs) and the niche microenvironment is an attractive avenue for cancer therapy. We show here, using a mouse model of squamous cell carcinoma, that TICs play a crucial role in creating a niche microenvironment that is required for tumor progression and drug resistance. Antioxidant activity in TICs, mediated by the transcription factor NRF2, facilitates the release of a nuclear cytokine, interleukin-33 (IL-33). This cytokine promotes differentiation of macrophages that express the high-affinity immunoglobulin E receptor FcεRIα and are in close proximity to TICs. In turn, these IL-33-responding FcεRIα+ macrophages send paracrine transforming growth factor ß (TGF-ß) signals to TICs, inducing invasive and drug-resistant properties and further upregulating IL-33 expression. This TIC-driven, IL-33-TGF-ß feedforward loop could potentially be exploited for cancer treatment.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Interleucina-33/metabolismo , Células-Tronco Neoplásicas/patologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Progressão da Doença , Humanos , Células-Tronco Neoplásicas/metabolismo , Transdução de Sinais , Microambiente Tumoral
11.
Ann Rheum Dis ; 79(9): 1227-1233, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32482644

RESUMO

OBJECTIVES: Coactivators are a heterogeneous family of transcriptional regulators that are essential for modulation of transcriptional outcomes and fine-tune numerous cellular processes. The aim of the present study was to evaluate the role of the coactivator peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) in the pathogenesis of systemic sclerosis (SSc). METHODS: Expression of PGC-1α was analysed by real-time PCR, western blot and immunofluorescence. Modulation of autophagy was analysed by reporter studies by expression of autophagy-related genes. The effects of PGC-1α knockdown on collagen production and myofibroblast differentiation were analysed in cultured human fibroblasts and in two mouse models with fibroblast-specific knockout of PGC-1α. RESULTS: The expression of PGC-1α was induced in dermal fibroblasts of patients with SSc and experimental murine fibrosis. Transforming growth factor beta (TGFß), hypoxia and epigenetic mechanisms regulate the expression of PGC-1α in fibroblasts. Knockdown of PGC-1α prevented the activation of autophagy by TGFß and this translated into reduced fibroblast-to-myofibroblast differentiation and collagen release. Knockout of PGC-1α in fibroblasts prevented skin fibrosis induced by bleomycin and by overexpression of a constitutively active TGFß receptor type I. Moreover, pharmacological inhibition of PGC-1α by SR18292 induced regression of pre-established, bleomycin-induced skin fibrosis. CONCLUSION: PGC-1α is upregulated in SSc and promotes autophagy to foster TGFß-induced fibroblast activation. Targeting of PGC-1α prevents aberrant autophagy, inhibits fibroblast activation and tissue fibrosis and may over therapeutic potential.


Assuntos
Autofagia/genética , Fibroblastos/fisiologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/fisiologia , Escleroderma Sistêmico/genética , Escleroderma Sistêmico/patologia , Animais , Bleomicina/farmacologia , Western Blotting , Colágeno/biossíntese , Modelos Animais de Doenças , Fibrose , Imunofluorescência , Humanos , Camundongos , Reação em Cadeia da Polimerase , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , Regulação para Cima
12.
Nucleic Acids Res ; 48(13): 7169-7181, 2020 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-32544250

RESUMO

The modulation of GLI2, an oncogenic transcription factor commonly upregulated in cancer, is in many cases not due to genetic defects, suggesting dysregulation through alternative mechanisms. The identity of these molecular events remains for the most part unknown. Here, we identified TFII-I as a novel repressor of GLI2 expression. Mapping experiments suggest that the INR region of the GLI2 promoter is necessary for GLI2 repression. ChIP studies showed that TFII-I binds to this INR. TFII-I knockdown decreased the binding of NELF-A, a component of the promoter-proximal pausing complex at this site, and enriched phosphorylated RNAPII serine 2 in the GLI2 gene body. Immunoprecipitation studies demonstrate TFII-I interaction with SPT5, another pausing complex component. TFII-I overexpression antagonized GLI2 induction by TGFß, a known activator of GLI2 in cancer cells. TGFß reduced endogenous TFII-I binding to the INR and increased RNAPII SerP2 in the gene body. We demonstrate that this regulatory mechanism is not exclusive of GLI2. TGFß-induced genes CCR7, TGFß1 and EGR3 showed similar decreased TFII-I and NELF-A INR binding and increased RNAPII SerP2 in the gene body post-TGFß treatment. Together these results identify TFII-I as a novel repressor of a subset of TGFß-responsive genes through the regulation of RNAPII pausing.


Assuntos
Proteínas Nucleares/metabolismo , RNA Polimerase II/metabolismo , Fatores de Transcrição TFII/fisiologia , Fator de Crescimento Transformador beta/metabolismo , Proteína Gli2 com Dedos de Zinco/metabolismo , Células Hep G2 , Humanos , Regiões Promotoras Genéticas , Proteínas Repressoras/fisiologia , Transcrição Genética , Ativação Transcricional
13.
PLoS Genet ; 16(6): e1008774, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32555736

RESUMO

Cranial neural crest (NC) contributes to the developing vertebrate eye. By multidimensional, quantitative imaging, we traced the origin of the ocular NC cells to two distinct NC populations that differ in the maintenance of sox10 expression, Wnt signalling, origin, route, mode and destination of migration. The first NC population migrates to the proximal and the second NC cell group populates the distal (anterior) part of the eye. By analysing zebrafish pax6a/b compound mutants presenting anterior segment dysgenesis, we demonstrate that Pax6a/b guide the two NC populations to distinct proximodistal locations. We further provide evidence that the lens whose formation is pax6a/b-dependent and lens-derived TGFß signals contribute to the building of the anterior segment. Taken together, our results reveal multiple roles of Pax6a/b in the control of NC cells during development of the anterior segment.


Assuntos
Segmento Anterior do Olho/metabolismo , Crista Neural/metabolismo , Neurogênese , Fator de Transcrição PAX6/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Animais , Segmento Anterior do Olho/citologia , Segmento Anterior do Olho/embriologia , Movimento Celular , Mutação , Crista Neural/citologia , Crista Neural/embriologia , Neurônios/citologia , Neurônios/metabolismo , Fator de Transcrição PAX6/genética , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/genética
14.
Gene ; 756: 144916, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32580008

RESUMO

Chronic idiopathic urticaria (CIU) is an unfavorable skin condition which could be maintained for six weeks or longer time. Gremlin1 (GREM1) was recently applied in treatments of many diseases. However, the possible regulatory mechanism of GREM1 in CIU remained unclear. This study aimed to explore the regulatory effects of GREM1 on the inflammatory response and vascular permeability mediated by mast cells of CIU via TGF-ß signaling pathway. Initially, microarray analysis was used to identify CIU-related differentially expressed genes and the potential mechanism of this gene. A mouse model of CIU was established. To explore the functional role of GREM1 in CIU, the modeled mice were then injected with GREM1-siRNA, SRI-011381 (the activator of TGF-ß signaling pathway), or both, followed by serum test, and immunoglobulin detection. The levels of inflammatory factors and tryptase, ß-hexosaminase, histamine in the serum were detected. Besides, vascular endothelial cell permeability and the target relation between GREM1 and TGF-ß were also examined. Mice injected with SRI-011381 exhibited higher levels of tryptase, ß-hexosaminase, histamine, inflammation-related factors and increased vascular endothelial cell permeability, while GREM1-silenced mice yet expressed opposite tendency. Silencing of GREM1 was demonstrated to inhibit the TGF-ß signaling pathway. Taken together, our results demonstrated that down-regulation of GREM1 could potentially impede inflammatory response and vascular permeability by suppressing TGF-ß signaling pathway. GREM1 may promote the development of prognosis management and therapeutic treatment in CIU.


Assuntos
Urticária Crônica/genética , Modelos Animais de Doenças , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Animais , Células Cultivadas , Urticária Crônica/patologia , Regulação para Baixo , Células Endoteliais/metabolismo , Feminino , Humanos , Inflamação/genética , Masculino , Mastócitos/metabolismo , Camundongos , RNA Interferente Pequeno/administração & dosagem , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo
15.
Nat Commun ; 11(1): 3020, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32541686

RESUMO

The subversion of endocytic routes leads to malignant transformation and has been implicated in human cancers. However, there is scarce evidence for genetic alterations of endocytic proteins as causative in high incidence human cancers. Here, we report that Epsin 3 (EPN3) is an oncogene with prognostic and therapeutic relevance in breast cancer. Mechanistically, EPN3 drives breast tumorigenesis by increasing E-cadherin endocytosis, followed by the activation of a ß-catenin/TCF4-dependent partial epithelial-to-mesenchymal transition (EMT), followed by the establishment of a TGFß-dependent autocrine loop that sustains EMT. EPN3-induced partial EMT is instrumental for the transition from in situ to invasive breast carcinoma, and, accordingly, high EPN3 levels are detected at the invasive front of human breast cancers and independently predict metastatic rather than loco-regional recurrence. Thus, we uncover an endocytic-based mechanism able to generate TGFß-dependent regulatory loops conferring cellular plasticity and invasive behavior.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Neoplasias da Mama/fisiopatologia , Endocitose , Proteínas Adaptadoras de Transporte Vesicular/genética , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Caderinas/genética , Caderinas/metabolismo , Transição Epitelial-Mesenquimal , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica , Metástase Neoplásica , Transdução de Sinais , Fator de Transcrição 4/genética , Fator de Transcrição 4/metabolismo , Fator de Crescimento Transformador beta/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
16.
Cell Prolif ; 53(8): e12859, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32588946

RESUMO

OBJECTIVES: Bone mesenchymal stem cells (BMSCs) play critical roles in tumour microenvironment. However, molecular mechanisms of how BMSCs to be recruited and effect subsequent tumour progression are poorly understood in oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: The distribution of CXCL8 was detected by immunohistochemical staining in OSCC tissues. The chemotaxis of conditioned media from different epithelial cells to BMSCs was examined by trans-well assay. Real-time quantitative PCR (qPCR) and ELISA were used to detect the expression of related cytokines and chemokine receptors. The migration of BMSCs was observed in BALB/c nude mice. The roles of BMSCs in proliferation, migration and invasion of OSCC were detected by CCK-8, flow cytometry and trans-well assay. Epithelial-mesenchymal transition (EMT)-related markers were analysed by qPCR and Western blot in vitro, and growth was evaluated in BALB/c nude mice using subcutaneously implanted OSCC in nude mouse model in vivo. RESULTS: Using OSCC, we show CXCL8, secreted by OSCC, binds to exclusively CXCR2 in BMSCs to facilitate migration of BMSCs to OSCC. TGF-ß secreted by BMSCs subsequently induces EMT of OSCC to promote their proliferation, migration and infiltration. We also showed that the Ras/Raf/Erk axis plays a critical role in tumour progression. CONCLUSIONS: Our results provide the molecular basis for BMSC recruitment into tumours, and how this process leads to tumour progression and leads us to develop a novel OSCC treatment target.


Assuntos
Carcinoma de Células Escamosas/patologia , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica/genética , Células-Tronco Mesenquimais/citologia , Neoplasias Bucais/genética , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Animais , Caderinas/metabolismo , Carcinoma de Células Escamosas/genética , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Interleucina-8/metabolismo , Masculino , Camundongos Nus , Neoplasias Bucais/imunologia , Receptores de Interleucina-8B/metabolismo , Microambiente Tumoral/fisiologia
17.
Life Sci ; 256: 117893, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32502539

RESUMO

AIMS: To investigate the effect and underlying mechanism of melittin and tripartite motif (TRIM) family in human embryonic lung fibroblast (HELF). MATERIALS AND METHODS: Lentiviral RNA interference vector and lentiviral overexpression vector were constructed and packaged by transfecting 293T cells; the proliferation of HELF was examined using Cell Counting Kit 8; Western blot and qRT-PCR were performed to examine protein and mRNA expression; the interaction with protein phosphatase magnesium-dependent 1A (PPM1A) was examined by Co-immunoprecipitation. KEY FINDINGS: Compared with the control group, the mRNA expression of the TRIM6, TRIM8 and TRIM47 in the IPF group significantly increased. Melittin inhibited the mRNA expression and protein expression levels of TRIM47, the HELF proliferation, the hydroxyproline levels, and the phosphorylation of Smad2/3; the interference of TRIM47 inhibited the protein expression of Vimentin, α-SMA, CTGF, the phosphorylation of Smad2/3 and the synthesis of hydroxyproline; TRIM47 overexpression elevated the phosphorylation of Smad2/3, induced ubiquitination of PPM1A and decreased the expression level of PPM1A, while TRIM47 RNA interference reversed this result. SIGNIFICANCE: Melittin has anti-fibrotic effect in HELF by directly reducing the phosphorylation of Smad2/3 or indirectly reducing the phosphorylation of Smad2/3 by decreasing the expression levels of TRIM47 whose overexpression induces ubiquitination of PPM1A.


Assuntos
Proteínas de Transporte/metabolismo , Fibroblastos/metabolismo , Fibroblastos/patologia , Pulmão/embriologia , Meliteno/farmacologia , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , Transdução de Sinais , Actinas/metabolismo , Proteínas de Transporte/sangue , Proliferação de Células/efeitos dos fármacos , Fator de Crescimento do Tecido Conjuntivo/genética , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Fibroblastos/efeitos dos fármacos , Fibrose , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hidroxiprolina/metabolismo , Proteínas de Neoplasias/sangue , Proteínas Nucleares/sangue , Fosforilação/efeitos dos fármacos , Proteína Fosfatase 2C/metabolismo , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Ubiquitinação/efeitos dos fármacos , Vimentina/metabolismo
18.
Proc Natl Acad Sci U S A ; 117(27): 15935-15946, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32571912

RESUMO

Excessive tumor necrosis factor (TNF) is known to cause significant pathology. Paradoxically, deficiency in TNF (TNF-/-) also caused substantial pathology during respiratory ectromelia virus (ECTV) infection, a surrogate model for smallpox. TNF-/- mice succumbed to fulminant disease whereas wild-type mice, and those engineered to express only transmembrane TNF (mTNF), fully recovered. TNF deficiency did not affect viral load or leukocyte recruitment but caused severe lung pathology and excessive production of the cytokines interleukin (IL)-6, IL-10, transforming growth factor beta (TGF-ß), and interferon gamma (IFN-γ). Short-term blockade of these cytokines significantly reduced lung pathology in TNF-/- mice concomitant with induction of protein inhibitor of activated STAT3 (PIAS3) and/or suppressor of cytokine signaling 3 (SOCS3), factors that inhibit STAT3 activation. Consequently, inhibition of STAT3 activation with an inhibitor reduced lung pathology. Long-term neutralization of IL-6 or TGF-ß protected TNF-/- mice from an otherwise lethal infection. Thus, mTNF alone is necessary and sufficient to regulate lung inflammation but it has no direct antiviral activity against ECTV. The data indicate that targeting specific cytokines or cytokine-signaling pathways to reduce or ameliorate lung inflammation during respiratory viral infections is possible but that the timing and duration of the interventive measure are critical.


Assuntos
Citocinas/metabolismo , Infecções por Poxviridae/virologia , Poxviridae/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Interferon gama/metabolismo , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Poxviridae/imunologia , Infecções por Poxviridae/imunologia , Infecções por Poxviridae/patologia , Infecções Respiratórias/imunologia , Infecções Respiratórias/virologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Fator de Crescimento Transformador beta/metabolismo
19.
PLoS One ; 15(6): e0233767, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32531779

RESUMO

Functional and anatomical connection between the liver and the spleen is most clearly manifested in various pathological conditions of the liver (cirrhosis, hepatitis). The mechanisms of the interaction between the two organs are still poorly understood, as there have been practically no studies on the influence exerted by the spleen on the normal liver. Mature male Sprague-Dawley rats of 250-260 g body weight, 3 months old, were splenectomized. The highest numbers of Ki67+ hepatocytes in the liver of splenectomized rats were observed at 24 h after the surgery, simultaneously with the highest index of Ki67-positive hepatocytes. After surgical removal of the spleen, expression of certain genes in the liver tissues increased. A number of genes were upregulated in the liver at a single time point of 24 h, including Ccne1, Egf, Tnfa, Il6, Hgf, Met, Tgfb1r2 and Nos2. The expression of Ccnd1, Tgfb1, Tgfb1r1 and Il10 in the liver was upregulated over the course of 3 days after splenectomy. Monitoring of the liver macrophage populations in splenectomized animals revealed a statistically significant increase in the proportion of CD68-positive cells in the liver (as compared with sham-operated controls) detectable at 24 h and 48 h after the surgery. The difference in the liver content of CD68-positive cells between splenectomized and sham-operated animals evened out by day 3 after the surgery. No alterations in the liver content of CD163-positive cells were observed in the experiments. A decrease in the proportion of CD206-positive liver macrophages was observed at 48 h after splenectomy. The splenectomy-induced hepatocyte proliferation is described by us for the first time. Mechanistically, the effect is apparently induced by the removal of spleen as a major source of Tgfb1 (hepatocyte growth inhibitor) and subsequently supported by activation of proliferation factor-encoding genes in the liver.


Assuntos
Proliferação de Células , Hepatócitos/metabolismo , Esplenectomia/efeitos adversos , Animais , Hepatócitos/fisiologia , Interleucina-6/genética , Interleucina-6/metabolismo , Macrófagos/metabolismo , Macrófagos/fisiologia , Masculino , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Ratos Sprague-Dawley , Transcriptoma , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo
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