RESUMEN
Single-nucleotide polymorphisms in ETS1 are associated with systemic lupus erythematosus (SLE). Ets1-/- mice develop SLE-like symptoms, suggesting that dysregulation of this transcription factor is important to the onset or progression of SLE. We used conditional deletion approaches to examine the impact of Ets1 expression in different immune cell types. Ets1 deletion on CD4+ T cells, but not B cells or dendritic cells, resulted in the SLE autoimmunity, and this was associated with the spontaneous expansion of T follicular helper type 2 (Tfh2) cells. Ets1-/- Tfh2 cells exhibited increased expression of GATA-3 and interleukin-4 (IL-4), which induced IgE isotype switching in B cells. Neutralization of IL-4 reduced Tfh2 cell frequencies and ameliorated disease parameters. Mechanistically, Ets1 suppressed signature Tfh and Th2 cell genes, including Cxcr5, Bcl6, and Il4ra, thus curbing the terminal Tfh2 cell differentiation process. Tfh2 cell frequencies in SLE patients correlated with disease parameters, providing evidence for the relevance of these findings to human disease.
Asunto(s)
Diferenciación Celular/inmunología , Lupus Eritematoso Sistémico/inmunología , Proteína Proto-Oncogénica c-ets-1/inmunología , Células Th2/inmunología , Animales , Autoinmunidad/genética , Autoinmunidad/inmunología , Linfocitos B/inmunología , Linfocitos B/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Diferenciación Celular/genética , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Expresión Génica/inmunología , Perfilación de la Expresión Génica , Humanos , Lupus Eritematoso Sistémico/genética , Lupus Eritematoso Sistémico/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Proteína Proto-Oncogénica c-ets-1/genética , Proteína Proto-Oncogénica c-ets-1/metabolismo , Células Th2/metabolismoRESUMEN
The transcription factor NFAT1 plays a pivotal role in the homeostasis of T lymphocytes. However, its functional importance in non-CD4+ T cells, especially in systemic immune disorders, is largely unknown. In this study, we report that NFAT1 regulates dendritic cell (DC) tolerance and suppresses systemic autoimmunity using the experimental autoimmune myasthenia gravis (EAMG) as a model. Myasthenia gravis and EAMG are T cell-dependent, Ab-mediated autoimmune disorders in which the acetylcholine receptor is the major autoantigen. NFAT1-knockout mice showed higher susceptibility to EAMG development with enhanced Th1/Th17 cell responses. NFAT1 deficiency led to a phenotypic alteration of DCs that show hyperactivation of NF-κB-mediated signaling pathways and enhanced binding of NF-κB (p50) to the promoters of IL-6 and IL-12. As a result, NFAT1-knockout DCs produced much higher levels of proinflammatory cytokines such as IL-1ß, IL-6, IL-12, and TNF-α, which preferentially induce Th1/Th17 cell differentiation. Our data suggest that NFAT1 may limit the hyperactivation of the NF-κB-mediated proinflammatory response in DCs and suppress autoimmunity by serving as a key regulator of DC tolerance.
Asunto(s)
Células Dendríticas/inmunología , Activación de Linfocitos , Miastenia Gravis Autoinmune Experimental/inmunología , Factores de Transcripción NFATC/inmunología , Transducción de Señal/inmunología , Animales , Citocinas/genética , Citocinas/inmunología , Células Dendríticas/patología , Tolerancia Inmunológica/genética , Ratones , Ratones Transgénicos , Miastenia Gravis Autoinmune Experimental/genética , Miastenia Gravis Autoinmune Experimental/patología , FN-kappa B/genética , FN-kappa B/inmunología , Factores de Transcripción NFATC/genética , Transducción de Señal/genética , Células TH1/inmunología , Células TH1/patología , Células Th17/inmunología , Células Th17/patologíaRESUMEN
IL-31 is a key mediator of itching in atopic dermatitis (AD) and is preferentially produced by activated CD4(+) T cells and Th2 cells. Although pathophysiological functions of IL-31 have been suggested in diverse immune disorders, the molecular events underlying IL-31 gene regulation are still unclear. In this study we identified the transcription start site and functional promoter involved in IL-31 gene regulation in mouse CD4(+) T cells. TCR stimulation-dependent IL-31 expression was found to be closely linked with in vivo binding of NFAT1 and JunB to the IL-31 promoter. Although NFAT1 alone enhanced IL-31 promoter activity, it was further enhanced in the presence of JunB. Conversely, knockdown of either NFAT1 or JunB resulted in reduced IL-31 expression. NFAT1-deficient CD4(+) T cells showed a significant defect in IL-31 expression compared with wild-type CD4(+) T cells. In agreement with these findings, mice subjected to atopic conditions showed much higher levels of IL-31, which were closely correlated with a significant increase in the number of infiltrated NFAT1(+)CD4(+) T cells into the AD ears. Amelioration of AD progression by cyclosporin A treatment was well correlated with downregulation of IL-31 expressions in CD4(+) T cells and total ear residual cells. In summary, our results suggest a functional cooperation between NFAT1 and JunB in mediating IL-31 gene expression in CD4(+) T cells and indicate that interference with this interaction or their activity has the potential of reducing IL-31-mediated AD symptoms.
Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Dermatitis Atópica/inmunología , Regulación de la Expresión Génica/inmunología , Interleucinas/biosíntesis , Factores de Transcripción NFATC/inmunología , Factores de Transcripción/inmunología , Animales , Inmunoprecipitación de Cromatina , Dermatitis Atópica/genética , Dermatitis Atópica/metabolismo , Modelos Animales de Enfermedad , Femenino , Inmunohistoquímica , Interleucinas/genética , Interleucinas/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Mutagénesis Sitio-Dirigida , Factores de Transcripción NFATC/genética , ARN Interferente Pequeño , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Transcripción/genética , Transcriptoma , TransfecciónAsunto(s)
Dermatitis Atópica/terapia , Dermatitis por Contacto/terapia , Factores de Transcripción Forkhead/inmunología , Probióticos/uso terapéutico , Linfocitos T Reguladores/inmunología , Animales , Diferenciación Celular , Dermatitis Atópica/inmunología , Dermatitis por Contacto/inmunología , Haptenos/inmunología , Ratones Noqueados , Pyroglyphidae/inmunologíaRESUMEN
NFAT plays a crucial role in the immune system by regulating the transcription of inducible genes during immune responses. In T cells, NFAT proteins govern various cellular events related to T cell development, activation, tolerance induction, and differentiation. We previously reported the NFAT1-dependent enhancer activity of conserved noncoding sequence (CNS)-9, a distal cis-acting element, in the regulation of IL-10 transcription in T cells. In this study, we developed a T cell-based reporter system to identify compounds that modulate the regulatory activity of CNS-9. Among the identified candidates, 6-methoxyflavone (6-MF) significantly inhibited the enhancer activity of CNS-9, thereby reducing IL-10 expression in T cells without affecting cell viability. 6-MF also downregulated the transcription of NFAT1 target genes such as IL-4, IL-13, and IFN-γ. Treatment of 6-MF inhibited the translocation of NFAT1 into the nucleus, which consequently interrupted NFAT1 binding to the target loci, without affecting the expression or dephosphorylation of NFAT1. Treatment of 6-MF to CD4(+) T cells or B cells isolated from mice with atopic dermatitis significantly reduced disease-associated cytokine production, as well as the levels of IgE. In addition, oral administration of 6-MF to atopic dermatitis mice ameliorated disease symptoms by reducing serum IgE levels and infiltrating lymphocytes. Conclusively, our results suggest that 6-MF can be a potential candidate for the development of an effective immunomodulator via the suppression of NFAT-mediated T cell activation.
Asunto(s)
Transporte Activo de Núcleo Celular/inmunología , Flavonas/farmacología , Activación de Linfocitos/efectos de los fármacos , Factores de Transcripción NFATC/inmunología , Animales , Linfocitos B/inmunología , Linfocitos T CD4-Positivos/inmunología , Diferenciación Celular/inmunología , Línea Celular Tumoral , Núcleo Celular , Secuencia Conservada/efectos de los fármacos , Secuencia Conservada/genética , Citocinas/biosíntesis , Proteínas de Unión al ADN/genética , Dermatitis Atópica/tratamiento farmacológico , Dermatitis Atópica/inmunología , Células HEK293 , Humanos , Inmunoglobulina E/sangre , Interferón gamma/biosíntesis , Interferón gamma/genética , Interleucina-10/biosíntesis , Interleucina-10/genética , Interleucina-13/biosíntesis , Interleucina-13/genética , Interleucina-4/biosíntesis , Interleucina-4/genética , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Factores de Transcripción NFATC/antagonistas & inhibidores , Fosforilación , Unión Proteica/efectos de los fármacos , ARN no Traducido/efectos de los fármacos , ARN no Traducido/genética , Transcripción GenéticaRESUMEN
IL-10 is a multifunctional cytokine that plays a crucial role in immunity and tolerance. IL-10 is produced by diverse immune cell types, including B cells and subsets of T cells. Although Th1 produce IL-10, their expression levels are much lower than Th2 cells under conventional stimulation conditions. The potential role of E26 transformation-specific 1 (Ets-1) transcription factor as a negative regulator for Il10 gene expression in CD4(+) T cells has been implicated previously. In this study, we investigated the underlying mechanism of Ets-1-mediated Il10 gene repression in Th1 cells. Compared with wild type Th1 cells, Ets-1 knockout Th1 cells expressed a significantly higher level of IL-10, which is comparable with that of wild type Th2 cells. Upregulation of IL-10 expression in Ets-1 knockout Th1 cells was accompanied by enhanced chromatin accessibility and increased recruitment of histone H3 acetylation at the Il10 regulatory regions. Reciprocally, Ets-1 deficiency significantly decreased histone deacetylase 1 (HDAC1) enrichment at the Il10 regulatory regions. Treatment with trichostatin A, an inhibitor of HDAC family, significantly increased Il10 gene expression by increasing histone H3 acetylation recruitment. We further demonstrated a physical interaction between Ets-1 and HDAC1. Coexpression of Ets-1 with HDAC1 synergistically repressed IL-10 transcription activity. In summary, our data suggest that an interaction of Ets-1 with HDAC1 represses the Il10 gene expression in Th1 cells.
Asunto(s)
Regulación hacia Abajo/inmunología , Regulación de la Expresión Génica/inmunología , Histona Desacetilasa 1/fisiología , Interleucina-10/antagonistas & inhibidores , Interleucina-10/biosíntesis , Proteína Proto-Oncogénica c-ets-1/fisiología , Células TH1/inmunología , Células TH1/metabolismo , Animales , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Células Cultivadas , Regulación hacia Abajo/genética , Células HEK293 , Histona Desacetilasa 1/antagonistas & inhibidores , Histona Desacetilasa 1/metabolismo , Humanos , Interleucina-10/genética , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Proteína Proto-Oncogénica c-ets-1/deficiencia , Proteína Proto-Oncogénica c-ets-1/metabolismo , Células TH1/citología , Regulación hacia Arriba/genética , Regulación hacia Arriba/inmunologíaRESUMEN
BACKGROUND: The global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to approximately 500 million cases and 6 million deaths worldwide. Previous investigations into the pathophysiology of SARS-CoV-2 primarily focused on peripheral blood mononuclear cells from patients, lacking detailed mechanistic insights into the virus's impact on inflamed tissue. Existing animal models, such as hamster and ferret, do not faithfully replicate the severe SARS-CoV-2 infection seen in patients, underscoring the need for more relevant animal system-based research. METHODS: In this study, we employed single-cell RNA sequencing (scRNA-seq) with lung tissues from K18-hACE2 transgenic (TG) mice during SARS-CoV-2 infection. This approach allowed for a comprehensive examination of the molecular and cellular responses to the virus in lung tissue. FINDINGS: Upon SARS-CoV-2 infection, K18-hACE2 TG mice exhibited severe lung pathologies, including acute pneumonia, alveolar collapse, and immune cell infiltration. Through scRNA-seq, we identified 36 different types of cells dynamically orchestrating SARS-CoV-2-induced pathologies. Notably, SPP1+ macrophages in the myeloid compartment emerged as key drivers of severe lung inflammation and fibrosis in K18-hACE2 TG mice. Dynamic receptor-ligand interactions, involving various cell types such as immunological and bronchial cells, defined an enhanced TGFß signaling pathway linked to delayed tissue regeneration, severe lung injury, and fibrotic processes. INTERPRETATION: Our study provides a comprehensive understanding of SARS-CoV-2 pathogenesis in lung tissue, surpassing previous limitations in investigating inflamed tissues. The identified SPP1+ macrophages and the dysregulated TGFß signaling pathway offer potential targets for therapeutic intervention. Insights from this research may contribute to the development of innovative diagnostics and therapies for COVID-19. FUNDING: This research was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (2020M3A9I2109027, 2021R1A2C2004501).
Asunto(s)
COVID-19 , Melfalán , gammaglobulinas , Animales , Cricetinae , Ratones , Humanos , SARS-CoV-2 , Leucocitos Mononucleares , Hurones , Bronquios , Factor de Crecimiento Transformador beta , Ratones Transgénicos , Modelos Animales de Enfermedad , PulmónRESUMEN
IL-9 regulates diverse inflammatory immune responses. Although the functional importance of IL-9 has been investigated in various pathophysiological conditions, molecular mechanisms by which TCR stimulation induced IL-9 gene expression are still unclear. In this study, we investigated the functional importance of the NFAT1 and NF-κB (p65) in IL-9 gene transcription in CD4(+) T cells. In vivo binding of NFAT1 and NF-κB (p65) to the IL-9 promoter was observed. NFAT1 binding induced a transcriptionally active chromatin configuration at the IL-9 promoter locus, whereas NF-κB (p65) binding transactivated the IL-9 promoter. Mouse deficient in NFAT1 shows a significant down-regulation of IL-9 expression that resulted from an inaccessible chromatin configuration at the IL-9 promoter. In parallel, knockdown of NF-κB (p65) also resulted in reduced IL-9 expression. In this process, NFAT1 plays a pivotal role as a core protein that creates an accessible platform for the assembly of transcription activators. The presence of NFAT1 correlates with recruitment of NF-κB (p65), p300, and active histone markers on the IL-9 promoter, resulting in a transcriptionally competent promoter. NFAT1 deficiency significantly reduced the recruitment of the above activation complex to the IL-9 promoter. In summary, our data suggest that functional cooperation of NFAT1 and NF-κB synergistically enhances IL-9 transcription in CD4(+) T cells.
Asunto(s)
Cromatina/metabolismo , Interleucina-9/genética , Factores de Transcripción NFATC/metabolismo , Factor de Transcripción ReIA/metabolismo , Activación Transcripcional , Animales , Secuencia de Bases , Sitios de Unión/genética , Linfocitos T CD4-Positivos/citología , Linfocitos T CD4-Positivos/metabolismo , Células Cultivadas , Cromatina/genética , Inmunoprecipitación de Cromatina , Células HEK293 , Humanos , Immunoblotting , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Datos de Secuencia Molecular , Mutación , Factores de Transcripción NFATC/genética , Regiones Promotoras Genéticas/genética , Unión Proteica , Interferencia de ARN , Homología de Secuencia de Ácido Nucleico , Factor de Transcripción ReIA/genéticaRESUMEN
The immunomodulatory effect of probiotics has been shown mainly in gastro-intestinal immune disorders and little information is available on the inflammation of central nervous system. Recently we reported that IRT5 probiotics, a mixture of 5 probiotics, could suppress diverse experimental inflammatory disorders. In this study, we evaluated the prophylactic and therapeutic effects of IRT5 probiotics in experimental autoimmune encephalomyelitis (EAE), a T cell mediated inflammatory autoimmune disease of the central nervous system. Pretreatment of IRT5 probiotics before disease induction significantly suppressed EAE development. In addition, treatment with IRT5 probiotics to the ongoing EAE delayed the disease onset. Administration of IRT5 probiotics inhibited the pro-inflammatory Th1/Th17 polarization, while inducing IL10(+) producing or/and Foxp3(+) regulatory T cells, both in the peripheral immune system and at the site of inflammation. Collectively, our data suggest that IRT5 probiotics could be applicable to modulate T cell mediated neuronal autoimmune diseases, including multiple sclerosis.
Asunto(s)
Encefalomielitis Autoinmune Experimental/terapia , Probióticos/uso terapéutico , Subgrupos de Linfocitos T/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/patología , Ratones , Ratones Endogámicos C57BL , Glicoproteína Mielina-Oligodendrócito/inmunología , Fragmentos de Péptidos/inmunología , Médula Espinal/patologíaRESUMEN
TCR signaling regulates multiple aspects of T cell function by controlling expression of various cytokine genes. IL-24 is a multifunctional cytokine belonging to the IL-10 family. It displays anticancer effects in diverse cancer cells and regulates immunopathology of psoriasis and rheumatoid arthritis. IL-24 also plays an important role in B cell differentiation. Mouse IL-24 gene is selectively expressed in activated Th2 cells upon TCR stimulation. However, the molecular mechanisms by which TCR stimulation induces IL-24 gene expression are still unclear. In this study, to elucidate the mechanism of Th2 cell-specific expression of IL-24, we identified a proximal promoter region (-157/+95 bp) that plays critical role in activating the IL-24 gene in Th2 cells. This region has a Th2 cell-specific open chromatin structure along with permissive histone modifications. In vivo binding of Stat6 and AP-1 (c-Jun) to the IL-24 promoter locus in Th2 cells synergistically transactivated the IL-24 promoter. Stat6 and c-Jun proteins were found to physically cooperate with each other and upregulated IL-24 gene transcription. Knockdown of either Stat6 or c-Jun suppressed endogenous IL-24 gene expression in Th2 cells. In summary, TCR stimulation induces IL-24 expression in Th2 cells by the coordinate action of Stat6 and c-Jun transcription factors at the transcriptional level.
Asunto(s)
Epítopos de Linfocito T/inmunología , Regulación de la Expresión Génica/inmunología , Interleucinas/biosíntesis , Proteínas Proto-Oncogénicas c-jun/fisiología , Factor de Transcripción STAT6/fisiología , Células Th2/inmunología , Células Th2/metabolismo , Animales , Secuencia de Bases , Línea Celular Tumoral , Células HEK293 , Humanos , Interleucinas/genética , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Regiones Promotoras Genéticas/inmunología , Unión Proteica/genética , Unión Proteica/inmunología , Ratas , Receptores de Antígenos de Linfocitos T/fisiología , Células Th2/citología , Factor de Transcripción AP-1/fisiología , Células Tumorales CultivadasRESUMEN
Probiotics, live microorganisms that confer health benefits when consumed in adequate amounts, have gained significant attention for their potential therapeutic applications. The beneficial effects of probiotics are believed to stem from their ability to enhance intestinal barrier function, inhibit pathogens, increase beneficial gut microbes, and modulate immune responses. However, clinical studies investigating the effectiveness of probiotics have yielded conflicting results, potentially due to the wide variety of probiotic species and strains used, the challenges in controlling the desired number of live microorganisms, and the complex interactions between bioactive substances within probiotics. Bacterial cell wall components, known as effector molecules, play a crucial role in mediating the interaction between probiotics and host receptors, leading to the activation of signaling pathways that contribute to the health-promoting effects. Previous reviews have extensively covered different probiotic effector molecules, highlighting their impact on immune homeostasis. Understanding how each probiotic component modulates immune activity at the molecular level may enable the prediction of immunological outcomes in future clinical studies. In this review, we present a comprehensive overview of the structural and immunological features of probiotic effector molecules, focusing primarily on Lactobacillus and Bifidobacterium. We also discuss current gaps and limitations in the field and propose directions for future research to enhance our understanding of probiotic-mediated immunomodulation.
Asunto(s)
Probióticos , Probióticos/uso terapéutico , Lactobacillus , Bacterias , Transducción de Señal , Bifidobacterium/metabolismoRESUMEN
Immune checkpoint therapies, such as programmed cell death ligand 1 (PD-L1) blockade, have shown remarkable clinical benefit in many cancers by restoring the function of exhausted T cells. Hence, the identification of novel PD-L1 regulators and the development of their inhibition strategies have significant therapeutic advantages. Here, we conducted pooled shRNA screening to identify regulators of membrane PD-L1 levels in lung cancer cells targeting druggable genes and cancer drivers. We identified WNK lysine deficient protein kinase 3 (WNK3) as a novel positive regulator of PD-L1 expression. The kinase-dead WNK3 mutant failed to elevate PD-L1 levels, indicating the involvement of its kinase domain in this function. WNK3 perturbation increased cancer cell death in cancer cell-immune cell coculture conditions and boosted the secretion of cytokines and cytolytic enzymes, promoting antitumor activities in CD4+ and CD8+ T cells. WNK463, a pan-WNK inhibitor, enhanced CD8+ T-cell-mediated antitumor activity and suppressed tumor growth as a monotherapy as well as in combination with a low-dose anti-PD-1 antibody in the MC38 syngeneic mouse model. Furthermore, we demonstrated that the c-JUN N-terminal kinase (JNK)/c-JUN pathway underlies WNK3-mediated transcriptional regulation of PD-L1. Our findings highlight that WNK3 inhibition might serve as a potential therapeutic strategy for cancer immunotherapy through its concurrent impact on cancer cells and immune cells.
Asunto(s)
Antígeno B7-H1 , Linfocitos T CD8-positivos , Neoplasias Pulmonares , Proteínas Serina-Treonina Quinasas , Animales , Ratones , Antígeno B7-H1/genética , Linfocitos T CD8-positivos/inmunología , Línea Celular Tumoral , Inmunoterapia , Neoplasias Pulmonares/genética , Humanos , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismoRESUMEN
Yeast is an integral part of mammalian microbiome, and like commensal bacteria, has the potential of being harnessed to influence immunity in clinical settings. However, functional specificities of yeast-derived immunoregulatory molecules remain elusive. Here we find that while under steady state, ß-1,3-glucan-containing polysaccharides potentiate pro-inflammatory properties, a relatively less abundant class of cell surface polysaccharides, dubbed mannan/ß-1,6-glucan-containing polysaccharides (MGCP), is capable of exerting potent anti-inflammatory effects to the immune system. MGCP, in contrast to previously identified microbial cell surface polysaccharides, through a Dectin1-Cox2 signaling axis in dendritic cells, facilitates regulatory T (Treg) cell induction from naïve T cells. Furthermore, through a TLR2-dependent mechanism, it restrains Th1 differentiation of effector T cells by suppressing IFN-γ expression. As a result, administration of MGCP display robust suppressive capacity towards experimental inflammatory disease models of colitis and experimental autoimmune encephalomyelitis (EAE) in mice, thereby highlighting its potential therapeutic utility against clinically relevant autoimmune diseases.
Asunto(s)
Inmunomodulación/efectos de los fármacos , Inmunomodulación/inmunología , Polisacáridos/inmunología , Saccharomyces cerevisiae/metabolismo , beta-Glucanos/inmunología , Animales , Linfocitos T CD4-Positivos , Diferenciación Celular/efectos de los fármacos , Colitis/inmunología , Colitis/patología , Ciclooxigenasa 2 , Células Dendríticas/inmunología , Encefalomielitis Autoinmune Experimental , Glucanos , Proteínas de Homeodominio/genética , Inmunidad , Lectinas Tipo C , Mananos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Polisacáridos/metabolismo , Polisacáridos/farmacología , Saccharomyces cerevisiae/genética , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología , Células TH1 , Zimosan , beta-Glucanos/metabolismo , beta-Glucanos/farmacologíaRESUMEN
ETS1 has shown dichotomous roles as an oncogene and a tumor suppressor gene in diverse cancers, but its functionality in breast cancer tumorigenesis still remains unclear. We utilized the Cancer Genome Atlas (TCGA) database to analyze comprehensive functions of ETS1 in human breast cancer (BRCA) patients by investigating its expression patterns and methylation status in relation to clinical prognosis. ETS1 expression was significantly diminished by hyper-methylation of the ETS1 promoter region in specimens from BRCA patients compared to a healthy control group. Moreover, ETS1 high BRCA patients showed better prognosis and longer survival compared to ETS1 low BRCA patients. Consistent with clinical evidence, comparative transcriptome analysis combined with CRISPR/Cas9 or shRNA based perturbation of ETS1 expression revealed direct as well as indirect mechanisms of ETS1 that hinder tumorigenesis of BRCA cells. Taken together, our study enlightens a novel function of ETS1 as a tumor suppressor in breast cancer cells.
RESUMEN
Breast cancer is highly aggressive and is the leading cause of cancer-related mortality in women in developed countries. The ETS proto-oncogene 1 (Ets1) has versatile roles during the cellular processes of cancer development. It is often highly expressed in breast cancers and mediates migration and invasion of human breast cancer cells. However, underlying mechanisms of Ets1 gene expression is still ambiguous. Here, we identified a core-regulatory element (CRE) located in the Ets1 promoter region (-540/-80 bp from TSS) that contains elements responsible for associating with NFATs and NF-κBs. Compared with the less metastatic breast cancer cells, metastatic breast cancer cells (MDA-MB-231) show open chromatin configurations in the CRE, which facilitates direct binding of NFATc2 and/or NFKB1/RELA complex to trans-activate Ets1 transcription. Moreover, enhanced level of Nfatc2 and Nfkb1 positively correlated with Ets1 expression in the human breast cancer specimens. Deletion of the CRE region by CRISPR/Cas9 system resulted in significant reduction in Ets1 expression, which led to alterations of Ets1-mediated transcription programs including tumor invasiveness-related genes. Proper regulation of Ets1 gene expression by targeting the NFATc2 and NFKB1/RELA interaction could be a potential therapeutic target for Ets1-mediated metastatic breast cancer.
RESUMEN
Dysregulation of intestinal microflora is linked to inflammatory disorders associated with compromised immunosuppressive functions of Foxp3+ T regulatory (Treg) cells. Although mucosa-associated commensal microbiota has been implicated in Treg generation, molecular identities of the "effector" components controlling this process remain largely unknown. Here, we have defined Bifidobacterium bifidum as a potent inducer of Foxp3+ Treg cells with diverse T cell receptor specificity to dietary antigens, commensal bacteria, and B. bifidum itself. Cell surface ß-glucan/galactan (CSGG) polysaccharides of B. bifidum were identified as key components responsible for Treg induction. CSGG efficiently recapitulated the activity of whole bacteria and acted via regulatory dendritic cells through a partially Toll-like receptor 2-mediated mechanism. Treg cells induced by B. bifidum or purified CSGG display stable and robust suppressive capacity toward experimental colitis. By identifying CSGG as a functional component of Treg-inducing bacteria, our studies highlight the immunomodulatory potential of CSGG and CSGG-producing microbes.
Asunto(s)
Bifidobacterium bifidum/inmunología , Factores de Transcripción Forkhead/inmunología , Polisacáridos/inmunología , Linfocitos T Reguladores/inmunología , Animales , Bifidobacterium bifidum/citología , Inflamación/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones NoqueadosRESUMEN
Allergic contact hypersensitivity (CHS) is an inflammatory skin disease mediated by allergen specific T cells. In this study, we investigated the role of transcription factor NFAT1 in the pathogenesis of contact hypersensitivity. NFAT1 knock out (KO) mice spontaneously developed CHS-like skin inflammation in old age. Healthy young NFAT1 KO mice displayed enhanced susceptibility to hapten-induced CHS. Both CD4(+) and CD8(+) T cells from NFAT1 KO mice displayed hyper-activated properties and produced significantly enhanced levels of inflammatory T helper 1(Th1)/Th17 type cytokines. NFAT1 KO T cells were more resistant to activation induced cell death (AICD), and regulatory T cells derived from these mice showed a partial defect in their suppressor activity. NFAT1 KO T cells displayed a reduced expression of apoptosis associated BCL-2/BH3 family members. Ectopic expression of NFAT1 restored the AICD defect in NFAT1 KO T cells and increased AICD in normal T cells. Recipient Rag2(-/-) mice transferred with NFAT1 KO T cells showed more severe CHS sensitivity due to a defect in activation induced hapten-reactive T cell apoptosis. Collectively, our results suggest the NFAT1 plays a pivotal role as a genetic switch in CD4(+)/CD8(+) T cell tolerance by regulating AICD process in the T cell mediated skin inflammation.
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Dermatitis por Contacto/inmunología , Dermatitis por Contacto/metabolismo , Factores de Transcripción NFATC/metabolismo , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Animales , Apoptosis/genética , Muerte Celular/genética , Muerte Celular/inmunología , Dermatitis Alérgica por Contacto/genética , Dermatitis Alérgica por Contacto/inmunología , Dermatitis Alérgica por Contacto/metabolismo , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Tolerancia Inmunológica , Inmunomodulación , Activación de Linfocitos/genética , Activación de Linfocitos/inmunología , Ratones , Ratones Noqueados , Factores de Transcripción NFATC/genética , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismoRESUMEN
Carcinoma-associated fibroblasts (CAFs) promote tumor invasion by secreting soluble factors. A tagged triazine library was screened in our novel transwell coculture model of CAF and oral squamous cell carcinoma (OSCC). We discovered compound S06, which reduced OSCC invasion by inhibiting secretion of CAF-derived proinvasive chemokines. The N-terminus of Hsp90 was found to be the cellular target of S06. Importantly, S06 did not induce hepatic toxicity, a side effect associated with well-known Hsp90 inhibitors. Moreover, S06 inhibited tumor cell migration in a zebrafish xenograft model. Our results demonstrate that Hsp90 is a novel target for stromal-based therapy to modulate proinvasive molecular crosstalk within the tumor microenvironment. Furthermore, S06 represents a new class of Hsp90 inhibitor and is an attractive candidate for anticancer drug development.