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1.
Int J Med Sci ; 21(6): 1176-1186, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774752

RESUMO

Background: To uncover the potential significance of JAK-STAT-SOCS1 axis in penile cancer, our study was the pioneer in exploring the altered expression processes of JAK-STAT-SOCS1 axis in tumorigenesis, malignant progression and lymphatic metastasis of penile cancer. Methods: In current study, the comprehensive analysis of JAK-STAT-SOCS1 axis in penile cancer was analyzed via multiple analysis approaches based on GSE196978 data, single-cell data (6 cancer samples) and bulk RNA data (7 cancer samples and 7 metastasis lymph nodes). Results: Our study observed an altered molecular expression of JAK-STAT-SOCS1 axis during three different stages of penile cancer, from tumorigenesis to malignant progression to lymphatic metastasis. STAT4 was an important dominant molecule in penile cancer, which mediated the immunosuppressive tumor microenvironment by driving the apoptosis of cytotoxic T cell and was also a valuable biomarker of immune checkpoint inhibitor treatment response. Conclusions: Our findings revealed that the complexity of JAK-STAT-SOCS1 axis and the predominant role of STAT4 in penile cancer, which can mediate tumorigenesis, malignant progression, and lymphatic metastasis. This insight provided valuable information for developing precise treatment strategies for patients with penile cancer.


Assuntos
Progressão da Doença , Janus Quinases , Metástase Linfática , Neoplasias Penianas , Fator de Transcrição STAT4 , Proteína 1 Supressora da Sinalização de Citocina , Humanos , Masculino , Neoplasias Penianas/patologia , Neoplasias Penianas/genética , Neoplasias Penianas/metabolismo , Proteína 1 Supressora da Sinalização de Citocina/genética , Proteína 1 Supressora da Sinalização de Citocina/metabolismo , Metástase Linfática/patologia , Metástase Linfática/genética , Janus Quinases/metabolismo , Fator de Transcrição STAT4/metabolismo , Fator de Transcrição STAT4/genética , Regulação Neoplásica da Expressão Gênica , Carcinogênese/genética , Carcinogênese/patologia , Transdução de Sinais , Microambiente Tumoral/imunologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia
2.
Free Radic Biol Med ; 218: 1-15, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38574973

RESUMO

Sjogren's syndrome (SS) is an autoimmune disease characterized by dysfunction of exocrine glands, such as salivary glands. However, the molecular mechanism of salivary secretion dysfunction in SS is still unclear. Given the significance of glutathione peroxidase 4 (GPX4) in cellular redox homeostasis, we hypothesized that dysregulation of GPX4 may play a pivotal role in the pathogenesis of salivary secretion dysfunction observed in SS. The salivary gland of SS patients and the SS mouse model exhibited reduced expression of the ferroptosis inhibitor GPX4 and the important protein aquaporin 5 (AQP5), which is involved in salivary secretion. GPX4 overexpression upregulated and GPX4 knockdown downregulated AQP5 expression in salivary gland epithelial cells (SGECs) and salivary secretion. Bioinformatics analysis of GSE databases from SS patients' salivary glands revealed STAT4 as a key intermediary regulator between GPX4 and AQP5. A higher level of nuclear pSTAT4 was observed in the salivary gland of the SS mouse model. GPX4 overexpression inhibited and GPX4 knockdown promoted STAT4 phosphorylation and nuclear translocation in SGECs. CHIP assay confirmed the binding of pSTAT4 within the promoter of AQP5 inhibiting AQP5 transcription. GPX4 downregulation accumulates intracellular lipid ROS in SGECs. Lipid ROS inhibitor ferrostatin-1 treatment during in vitro and in vivo studies confirmed that lipid ROS activates STAT4 phosphorylation and nuclear translocation in SGECs. In summary, the downregulated GPX4 in SGECs contributes to salivary secretion dysfunction in SS via the lipid ROS/pSTAT4/AQP5 axis. This study unraveled novel targets to revitalize the salivary secretion function in SS patients.


Assuntos
Aquaporina 5 , Células Epiteliais , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Espécies Reativas de Oxigênio , Fator de Transcrição STAT4 , Glândulas Salivares , Síndrome de Sjogren , Síndrome de Sjogren/metabolismo , Síndrome de Sjogren/genética , Síndrome de Sjogren/patologia , Animais , Humanos , Camundongos , Glândulas Salivares/metabolismo , Glândulas Salivares/patologia , Aquaporina 5/metabolismo , Aquaporina 5/genética , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT4/metabolismo , Fator de Transcrição STAT4/genética , Modelos Animais de Doenças , Feminino , Regulação para Baixo , Masculino , Transdução de Sinais , Regulação da Expressão Gênica , Ferroptose/genética , Saliva/metabolismo , Pessoa de Meia-Idade
3.
Tissue Eng Regen Med ; 21(4): 595-608, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38466361

RESUMO

BACKGROUND: The purpose of this study was to investigate the specific effects of signal transducer and activator of transcription 4 (STAT4)-induced long intergenic nonprotein coding RNA 1278 (LINC01278) on the growth of non-small cell lung cancer (NSCLC) cells involved in the microRNA (miR)-877-5p/activated transcription factor 4 (ATF4) axis. METHODS: NSCLC tumor tissue and adjacent normal tissue were collected. Human normal lung epithelial cell BEAS-2B and human NSCLC cell lines (H1299, H1975, A549, H2228) were collected. The expression levels of STAT4, LINC01278, miR-877-5p, and ATF4 were detected. A549 cells were screened for subsequent experiments. The proliferation ability of cells was detected by colony formation experiment. Cell apoptosis was tested by flow cytometry. Scratch test and transwell assay were used to detect the migration and invasion ability of cells. Biological function of LINC01278 in NSCLC was confirmed by xenograft experiments. RESULTS: Low expression miR-877-5p and high expression of STAT4, LINC01278 and ATF4 were detected in NSCLC. Silenced LINC01278 in A549 cell depressed cell proliferation, migration and invasion, but facilitated cell apoptosis. LINC01278 was positively correlated with STAT4 and could directly bind to miR-877-5p. Upregulating miR-877-5p suppressed NSCLC cell progression, while downregulating miR-877-5p had the opposite effect. Upregulating miR-877-5p abrogated the effects of silenced LINC01278 on NSCLC cell progression. MiR-877-5p targeted ATF4. ATF4 upregulation could partly restore the carcinogenic effect of LINC01278 in vitro and in vivo. CONCLUSION: Our data supports that STAT4-induced upregulation of LINC01278 promotes NSCLC progression by modulating the miR-877-5p/ATF4 axis, suggesting a novel direction for NSCLC treatment.


Assuntos
Fator 4 Ativador da Transcrição , Carcinoma Pulmonar de Células não Pequenas , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares , MicroRNAs , RNA Longo não Codificante , Fator de Transcrição STAT4 , Regulação para Cima , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Fator 4 Ativador da Transcrição/metabolismo , Fator 4 Ativador da Transcrição/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Animais , Fator de Transcrição STAT4/metabolismo , Fator de Transcrição STAT4/genética , Invasividade Neoplásica , Linhagem Celular Tumoral , Células A549 , Camundongos Nus , Camundongos , Apoptose , Feminino , Masculino , Movimento Celular , Camundongos Endogâmicos BALB C
4.
Int J Mol Sci ; 25(6)2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38542139

RESUMO

Our goal was to investigate the effects of epidermal growth factor (EGF) and interferons (IFNs) on signal transducer and activator of transcription STAT1 and STAT4 mRNA and active phosphorylated protein expression in Sjögren's syndrome cell culture models. iSGECs (immortalized salivary gland epithelial cells) and A253 cells were treated with EGF, IFN-alpha, -beta, -gamma, or mitogen-activated protein kinase p38 alpha (p38-MAPK) inhibitor for 0-24-48-72 h. STAT1 and STAT4 mRNA expression was quantified by qRT-PCR. Untreated and treated cells were compared using the delta-delta-CT method based on glyceraldehyde-3-phosphate dehydrogenase (GAPDH) normalized relative fold changes. phospho-tyrosine-701-STAT1 and phospho-serine-721-STAT4 were detected by Western blot analysis. STAT4 mRNA expression decreased 48 h after EGF treatment in A253 cells, immortalized salivary gland epithelial cells iSGECs nSS2 (sicca patient origin), and iSGECs pSS1 (anti-SSA negative Sjögren's Syndrome patient origin). EGF and p38-MAPK inhibitor decreased A253 STAT4 mRNA levels. EGF combined with IFN-gamma increased phospho-STAT4 and phospho-STAT1 after 72 h in all cell lines, suggesting additive effects for phospho-STAT4 and a major effect from IFN-gamma for phospho-STAT1. pSS1 and nSS2 cells responded differently to type I and type II interferons, confirming unique functional characteristics between iSGEC cell lines. EGF/Interferon related pathways might be targeted to regulate STAT1 and STAT4 expression in salivary gland epithelial cells. Further investigation is required learn how to better target the Janus kinases/signal transducer and activator of transcription proteins (JAK/STAT) pathway-mediated inflammatory response in Sjögren's syndrome.


Assuntos
Fator de Crescimento Epidérmico , Síndrome de Sjogren , Humanos , Fator de Crescimento Epidérmico/farmacologia , Fator de Crescimento Epidérmico/metabolismo , Síndrome de Sjogren/tratamento farmacológico , Síndrome de Sjogren/genética , Interferon-alfa/farmacologia , Fatores Imunológicos , Técnicas de Cultura de Células , RNA Mensageiro/metabolismo , Suplementos Nutricionais , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Fosforilação , Fator de Transcrição STAT4/genética , Fator de Transcrição STAT4/metabolismo
5.
Genes (Basel) ; 15(2)2024 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-38397230

RESUMO

Rheumatoid Arthritis (RA) is a multifactorial autoimmune disease. Currently, several genes play an important role in the development of the disease. The objective was to evaluate the association of the STAT4 rs7574865 and rs897200 gene variants with RA susceptibility, DAS28, RF, and anti-CCP in Western and Southern Mexico populations. Genotyping was performed on 476 samples (cases = 240; controls = 236) using the Taqman® system and qPCR probes. Disease activity was assessed using DAS28 and HAQ DI. CRP, ESR, RF, and anti-CCP were determined for clinical assessment. Our study showed there is a statistically significant association with susceptibility to RA for the rs7574865 variant in the Western population for the GT and TT genotypes. The same genotypes also showed a moderate-to-high activity according to DAS28 and positive anti-CCP compared to the control group. This association was not found in the Southern population. This work confirms the association of the rs7574865 variant with RA, as well as a moderate-to-high activity and positive anti-CCP in the Western population but not in the Southern population. No association of the rs897200 variant was found in any of the studied populations.


Assuntos
Anticorpos Antiproteína Citrulinada , Artrite Reumatoide , Humanos , México , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único/genética , Artrite Reumatoide/genética , Fator de Transcrição STAT4/genética
6.
Am J Physiol Cell Physiol ; 326(5): C1494-C1504, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38406824

RESUMO

Primary Sjögren's syndrome (pSS) is characterized by its autoimmune nature. This study investigates the role of the IFNγ SNP rs2069705 in modulating the susceptibility to pSS. Differential expression of IFNγ and BAFF was analyzed using the GEO database's mRNA microarray GSE84844. Genotyping of the IFNγ SNP rs2069705 was conducted via the dbSNP website. The JASPAR tool was used for predicting transcription factor bindings. Techniques such as dual-luciferase reporter assays, Chromatin immunoprecipitation, and analysis of a pSS mouse model were applied to study gene and protein interactions. A notable increase in the mutation frequency of IFNγ SNP rs2069705 was observed in MNCs from the exocrine glands of pSS mouse models. Bioinformatics analysis revealed elevated levels of IFNγ and BAFF in pSS samples. The model exhibited an increase in both CD20+ B cells and cells expressing IFNγ and BAFF. Knocking down IFNγ resulted in lowered BAFF expression and less lymphocyte infiltration, with BAFF overexpression reversing this suppression. Activation of the Janus kinase (JAK)/STAT1 pathway was found to enhance transcription in the BAFF promoter region, highlighting IFNγ's involvement in pSS. In addition, rs2069705 was shown to boost IFNγ transcription by promoting interaction between its promoter and STAT4. SNP rs2069705 in the IFNγ gene emerges as a pivotal element in pSS susceptibility, primarily by augmenting IFNγ transcription, activating the JAK/STAT1 pathway, and leading to B-lymphocyte infiltration in the exocrine glands.NEW & NOTEWORTHY The research employed a combination of bioinformatics analysis, genotyping, and experimental models, providing a multifaceted approach to understanding the complex interactions in pSS. We have uncovered that the rs2069705 SNP significantly affects the transcription of IFNγ, leading to altered immune responses and B-lymphocyte activity in pSS.


Assuntos
Linfócitos B , Interferon gama , Polimorfismo de Nucleotídeo Único , Síndrome de Sjogren , Ativação Transcricional , Animais , Feminino , Humanos , Camundongos , Fator Ativador de Células B/genética , Fator Ativador de Células B/metabolismo , Linfócitos B/imunologia , Linfócitos B/metabolismo , Modelos Animais de Doenças , Predisposição Genética para Doença , Interferon gama/genética , Interferon gama/metabolismo , Janus Quinases/metabolismo , Janus Quinases/genética , Polimorfismo de Nucleotídeo Único/genética , Transdução de Sinais , Síndrome de Sjogren/genética , Síndrome de Sjogren/imunologia , Síndrome de Sjogren/metabolismo , Síndrome de Sjogren/patologia , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT4/genética , Fator de Transcrição STAT4/metabolismo
7.
Biosci Rep ; 44(2)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38294290

RESUMO

Acute myelogenous leukemia (AML) is a common malignancy and is supposed to have the ability to escape host immune surveillance. The present study aimed to identify key genes in AML that may affect tumor immunity and to provide prognosis biomarkers of AML. The Cancer Genome Atlas (TCGA) dataset was screened for transcription factors (TFs) involved in immunity and influencing survival, combining Gene Expression Omnibus (GEO) data to validate the impact on patient survival. A prognostic signature was established using four transcription factors, and these genes play an important role in the immune system, with higher regulatory T cell (Treg) scores in high-risk patients compared with the low-risk group. Analysis of individual genes showed that STAT4 and Treg are closely related, which may be due to STAT4 transcribing related genes that affect immunity. STAT4 expression was positively correlated with the proportion of abnormal cells and promoted AML recurrence as verified by AML clinical patient samples. In addition, silencing of STAT4 significantly slowed down the proliferation capacity of HL60 cells. In conclusion, these findings suggest that STAT4 may be a potential biomarker for AML prognosis. As a key gene affecting the prognosis of AML patients, STAT4 has the potential to be a candidate diagnostic and prognostic biomarker for AML.


Assuntos
Leucemia Mieloide Aguda , Humanos , Prognóstico , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Fatores de Transcrição , Fatores de Risco , Biomarcadores , Fator de Transcrição STAT4/genética
8.
J Physiol Biochem ; 80(1): 219-233, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38091230

RESUMO

This study aimed to investigate the role of ERG in the HLX/STAT4/Perforin signaling axis, impacting natural killer (NK) cell cytotoxicity and myocardial infarction (MI) progression. NK cell cytotoxicity was assessed via co-culture and 51Cr release assays. Datasets GSE34198 and GSE97320 identified common differentially expressed genes in MI. NK cell gene expression was analyzed in MI patients and healthy individuals using qRT-PCR and Western blotting. ERG's regulation of HLX and STAT4's regulation of perforin were studied through computational tools (MEM) and ChIP experiments. HLX's influence on STAT4 was explored with the MG132 proteasome inhibitor. Findings were validated in a mouse MI model.ERG, a commonly upregulated gene, was identified in NK cells from MI patients and mice. ERG upregulated HLX, leading to STAT4 proteasomal degradation and reduced Perforin expression. Consequently, NK cell cytotoxicity decreased, promoting MI progression. ERG mediates the HLX/STAT4/Perforin axis to inhibit NK cell cytotoxicity, fostering MI progression. These results provide vital insights into MI's molecular mechanisms.


Assuntos
Citotoxicidade Imunológica , Células Matadoras Naturais , Animais , Humanos , Camundongos , Proteínas de Homeodomínio , Células Matadoras Naturais/metabolismo , Perforina/genética , Perforina/metabolismo , Transdução de Sinais , Fator de Transcrição STAT4/genética , Fator de Transcrição STAT4/metabolismo , Fatores de Transcrição/metabolismo , Regulador Transcricional ERG/metabolismo
9.
Proc Natl Acad Sci U S A ; 120(40): e2306761120, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37756335

RESUMO

Natural killer (NK) cells and type 1 innate lymphoid cells (ILC1) require signal transducer and activator of transcription 4 (STAT4) to elicit rapid effector responses and protect against pathogens. By combining genetic and transcriptomic approaches, we uncovered divergent roles for STAT4 in regulating effector differentiation of these functionally related cell types. Stat4 deletion in Ncr1-expressing cells led to impaired NK cell terminal differentiation as well as to an unexpected increased generation of cytotoxic ILC1 during intestinal inflammation. Mechanistically, Stat4-deficient ILC1 exhibited upregulation of gene modules regulated by STAT5 in vivo and an aberrant effector differentiation upon in vitro stimulation with IL-2, used as a prototypical STAT5 activator. Moreover, STAT4 expression in NCR+ innate lymphocytes restrained gut inflammation in the dextran sulfate sodium-induced colitis model limiting pathogenic production of IL-13 from adaptive CD4+ T cells in the large intestine. Collectively, our data shed light on shared and distinctive mechanisms of STAT4-regulated transcriptional control in NK cells and ILC1 required for intestinal inflammatory responses.


Assuntos
Antineoplásicos , Fator de Transcrição STAT5 , Humanos , Imunidade Inata , Diferenciação Celular , Células Matadoras Naturais , Inflamação , Fator de Transcrição STAT4/genética
10.
Oncol Rep ; 50(1)2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37264954

RESUMO

Ovarian serous carcinoma (OC) is a common cause of mortality among gynecological malignancies. Although tumor­infiltrating CD8 T cells are associated with a favorable prognosis of OC, the underlying mechanisms are not clearly understood. The present study identified the key genes and potential molecular mechanisms associated with CD8 T­cell infiltration in OC. The score of CD8 T cells in The Cancer Genome Atlas dataset (376 samples from patients with OC) was estimated using the quanTIseq and MCP­counter algorithms. Thereafter, a protein­protein interaction network of differentially expressed genes was constructed and the hub genes were identified using cytoHubba in Cytoscape. The results revealed that signal transducer and activator of transcription 4 (STAT4) was strongly correlated with CD8 T­cell infiltration in OC. Furthermore, the prognostic value of STAT4 in OC was verified by Kaplan­Meier curve, and univariate and multivariate analyses. The biological functions of STAT4 were determined by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses, which revealed that STAT4 is closely related to cytokines in OC. Moreover, Spearman correlation analysis suggested that STAT4 was most positively correlated with CC chemokine ligand 5 (CCL5). CCL5 was revealed to be critical for orchestrating T­cell infiltration in tumors. Moreover, immunohistochemistry and reverse transcription­quantitative PCR showed that STAT4, CCL5 and CD8A (a marker for CD8 T cells) were closely related in OC. Moreover, in vitro analysis revealed that STAT4 knockdown led to a decrease in CCL5 expression and CD8 T­cell migration. Taken together, the present study suggested that STAT4 may regulate CD8 T­cell infiltration in OC tissues by inducing CCL5 secretion. Furthermore, STAT4 may be considered a promising prognostic biomarker for OC.


Assuntos
Carcinoma , Neoplasias Ovarianas , Humanos , Feminino , Quimiocinas CC/metabolismo , Ligantes , Prognóstico , Linfócitos T CD8-Positivos/metabolismo , Carcinoma/patologia , Neoplasias Ovarianas/patologia , Quimiocina CCL5/genética , Quimiocina CCL5/metabolismo , Fator de Transcrição STAT4/genética , Fator de Transcrição STAT4/metabolismo
11.
Int J Mol Sci ; 24(8)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37108746

RESUMO

Single nucleotide polymorphisms in non-HLA genes are involved in the development of rheumatoid arthritis (RA). SNPS in genes: PADI4 (rs2240340), STAT4 (rs7574865), CD40 (rs4810485), PTPN22 (rs2476601), and TRAF1 (rs3761847) have been described as risk factors for the development of autoimmune diseases, including RA. This study aimed to assess the prevalence of polymorphisms of these genes in the Polish population of patients with rheumatoid arthritis as compared to healthy controls. 324 subjects were included in the study: 153 healthy subjects and 181 patients from the Department of Rheumatology, Medical University of Lodz who fulfilled the criteria of rheumatoid arthritis diagnosis. Genotypes were determined by Taqman SNP Genotyping Assay. rs2476601 (G/A, OR = 2.16, CI = 1.27-3.66; A/A, OR = 10.35, CI = 1.27-84.21), rs2240340 (C/T, OR = 4.35, CI = 2.55-7.42; T/T, OR = 2.80, CI = 1.43-4.10) and rs7574865 (G/T, OR = 1.97, CI = 1.21-3.21; T/T, OR = 3.33, CI = 1.01-11.02) were associated with RA in the Polish population. Rs4810485 was also associated with RA, however after Bonferroni's correction was statistically insignificant. We also found an association between minor alleles of rs2476601, rs2240340, and rs7574865 and RA (OR = 2.32, CI = 1.47-3.66; OR = 2.335, CI = 1.64-3.31; OR = 1.88, CI = 1.27-2.79, respectively). Multilocus analysis revealed an association between CGGGT and rare (below 0.02 frequency) haplotypes (OR = 12.28, CI = 2.65-56.91; OR = 3.23, CI = 1.63-6.39). In the Polish population, polymorphisms of the PADI4, PTPN22, and STAT4 genes have been detected, which are also known risk factors for RA in various other populations.


Assuntos
Artrite Reumatoide , Polimorfismo de Nucleotídeo Único , Humanos , Fator 1 Associado a Receptor de TNF/genética , Polônia/epidemiologia , Predisposição Genética para Doença , Artrite Reumatoide/epidemiologia , Artrite Reumatoide/genética , Genótipo , Alelos , Estudos de Casos e Controles , Frequência do Gene , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Fator de Transcrição STAT4/genética
12.
J Biol Chem ; 299(5): 104703, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37059181

RESUMO

The conversion of signal transducer and activator of transcription (STAT) proteins from latent to active transcription factors is central to cytokine signaling. Triggered by their signal-induced tyrosine phosphorylation, it is the assembly of a range of cytokine-specific STAT homo- and heterodimers that marks a key step in the transition of hitherto latent proteins to transcription activators. In contrast, the constitutive self-assembly of latent STATs and how it relates to the functioning of activated STATs is understood less well. To provide a more complete picture, we developed a co-localization-based assay and tested all 28 possible combinations of the seven unphosphorylated STAT (U-STAT) proteins in living cells. We identified five U-STAT homodimers-STAT1, STAT3, STAT4, STAT5A, and STAT5B-and two heterodimers-STAT1:STAT2 and STAT5A:STAT5B-and performed semi-quantitative assessments of the forces and characterizations of binding interfaces that support them. One STAT protein-STAT6-was found to be monomeric. This comprehensive analysis of latent STAT self-assembly lays bare considerable structural and functional diversity in the ways that link STAT dimerization before and after activation.


Assuntos
Regulação da Expressão Gênica , Fatores de Transcrição STAT , Transativadores , Citocinas/metabolismo , Fosforilação , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT2/genética , Fator de Transcrição STAT2/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT4/genética , Fator de Transcrição STAT4/metabolismo , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT5/metabolismo , Transativadores/metabolismo , Fatores de Transcrição STAT/genética , Fatores de Transcrição STAT/metabolismo , Multimerização Proteica
13.
Genes (Basel) ; 14(3)2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36980810

RESUMO

STAT4 plays an important role in disease activity in SLE patients. STAT4 particles have the capacity to activate the transcription of genes associated with the production of TH1 and Th17 lymphocytes, with a greater predominance on the production of IFN-γ and IL-17A. The presence of variants in STAT4 genes has a major impact on the generation of autoimmunity. However, there are few studies evaluating the impact of these variants on the production of proinflammatory cytokines such as IFN-γ and IL-17A. Methods-A case-control study was carried out with 206 Mexican mestizo patients residing in Western Mexico with a diagnosis of SLE and a group of 80 patients without autoimmune diseases was captured to determine the cut-off point for high IFN-γ levels. In this study, SLE patients with high IFN-γ levels were considered as cases (cut-off > 15.6 pg/mL), and SLE patients with normal IFN-γ levels were considered as controls (cut-off ≤ 15.6 pg/mL). Disease activity was identified from the systemic lupus erythematosus disease activity index (SLEDAI). For the determination of levels of cytokines IFN-γ, IL-12, and IL17A, commercial ELISA kits were used. Genotyping of STAT4 rs7574865 (G > T) was performed by quantitative polymerase chain reaction (qPCR) using TaqMan probes. Results-The patients with SLE had a median age of 45 years with a range of disease duration from 4 years to 18 years; 45.6% were identified as having disease activity. In this sample, we identified a high IFN-γ prevalence of 35.4%. The levels of IFN-γ were higher in the patients with genotype TT than GG. We found that TT genotype conferred a higher risk of high IFN-γ when compared to the GG and GT genotypes. Conclusions-In this study, we identified that the polymorphic genotype TT of the STAT4 gene rs7574865 polymorphism is associated with increased levels of IFN-γ. However, its strength of association was weak, so complementary studies are needed to evaluate its impact on SLE patients.


Assuntos
Doenças Autoimunes , Interferon gama , Lúpus Eritematoso Sistêmico , Fator de Transcrição STAT4 , Pré-Escolar , Humanos , Alelos , Doenças Autoimunes/genética , Doenças Autoimunes/metabolismo , Estudos de Casos e Controles , Citocinas/genética , Predisposição Genética para Doença , Interferon gama/genética , Interleucina-17/genética , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/metabolismo , Polimorfismo de Nucleotídeo Único , Fator de Transcrição STAT4/genética
14.
Haematologica ; 108(5): 1385-1393, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36226497

RESUMO

Congenital amegakaryocytic thrombocytopenia (CAMT) is a recessive disorder characterized by severe reduction of megakaryocytes and platelets at birth, which evolves toward bone marrow aplasia in childhood. CAMT is mostly caused by mutations in MPL (CAMT-MPL), the gene encoding the receptor of thrombopoietin (THPO), a crucial cytokine regulating hematopoiesis. CAMT can be also due to mutations affecting the THPO coding region (CAMT-THPO). In a child with the clinical picture of CAMT, we identified the homozygous c.-323C>T substitution, affecting a potential regulatory region of THPO. Although mechanisms controlling THPO transcription are not characterized, bioinformatics and in vitro analysis showed that c.-323C>T prevents the binding of transcription factors ETS1 and STAT4 to the putative THPO promoter, impairing THPO expression. Accordingly, in the proband the serum THPO concentration indicates defective THPO production. Based on these findings, the patient was treated with the THPO-mimetic agent eltrombopag, which induced a significant increase in platelet count and stable remission of bleeding symptoms. Herein, we report a novel pathogenic variant responsible for CAMT and provide new insights into the mechanisms regulating transcription of the THPO gene.


Assuntos
Receptores de Trombopoetina , Trombopoetina , Criança , Recém-Nascido , Humanos , Trombopoetina/farmacologia , Receptores de Trombopoetina/genética , Mutação , Megacariócitos/patologia , Regiões Promotoras Genéticas , Proteína Proto-Oncogênica c-ets-1/genética , Fator de Transcrição STAT4/genética
15.
Arthritis Rheumatol ; 75(6): 961-972, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36575804

RESUMO

OBJECTIVE: Variants in STAT4 are associated with systemic lupus erythematosus (SLE) and other autoimmune diseases. We undertook this study to investigate how disease-associated variants affect STAT4 expression, in particular in CD4+ T cells where STAT4 plays an essential role. METHODS: We compared Th1 differentiation between naive CD4+ T cells from healthy donors homozygous for the risk (R/R) or nonrisk (NR/NR) alleles. We analyzed epigenetic marks in STAT4 and evaluated the relevance of its third intron, assessed the consequences of Stat4 overexpression in vivo in mice, and analyzed the effects of the STAT4 genotype in patients with lupus nephritis. RESULTS: Naive CD4+ T cells from NR/NR healthy donors down-regulated STAT4 in response to interleukin-12 (IL-12). In contrast, cells from R/R healthy donors maintained high levels. R/R cells exhibited a higher abundance of transcriptionally active STAT4 and increased interferon-γ production. Accordingly, R/R healthy donors exhibited a stronger induction of local active enhancer marks. Genetic editing confirmed the presence of a negative regulatory region in the STAT4 third intron, where most of the SLE-associated STAT4 single-nucleotide polymorphisms (SNPs) are located. In vivo forced expression demonstrated that increases in Stat4 levels in T cells enhanced glomerulonephritis in mice. Accordingly, the R/R genotype was associated with suboptimal response to treatment and with worse clinical outcomes in patients with proliferative lupus nephritis. CONCLUSION: The SLE-associated STAT4 haplotype correlates with an abnormal IL-12-mediated STAT4 transcriptional regulation. Carriers of the risk variant exhibit exaggerated CD4+ proinflammatory capacities that, in the context of SLE, contribute to more severe disease. R/R patients may benefit from blockade of the IL-12/STAT4 pathway.


Assuntos
Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Animais , Camundongos , Linfócitos T CD4-Positivos/metabolismo , Regulação para Baixo , Haplótipos , Interferon gama/genética , Interleucina-12 , Lúpus Eritematoso Sistêmico/genética , Nefrite Lúpica/genética , Polimorfismo de Nucleotídeo Único , Fator de Transcrição STAT4/genética , Humanos
16.
Mol Carcinog ; 61(10): 933-940, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35880842

RESUMO

Signal transducer and activator of transcription 4 (STAT4) is closely related to liver diseases and affects the processes of inflammation and carcinogenesis by regulating immune responses. A single-nucleotide polymorphism rs7574865 (T > G) in STAT4 has been reported to be associated with the risk of hepatocellular carcinoma (HCC). In addition, hepatitis B virus (HBV) mutations are crucial risk factors for HBV-induced HCC. However, the effects of the interactions of STAT4 rs7574865 with HBV mutations on the risk of HCC remain unknown. Rs7574865 was genotyped in 846 healthy controls (HCs), 968 chronic hepatitis B (CHB) subjects, 316 liver cirrhosis (LC) subjects and 1021 HCC subjects using Sequenom MassArray. HBV mutations were detected via direct sequencing. Multivariate logistic regression analysis was used to evaluate the effects of the interactions of STAT4 rs7574865 with HBV mutations on the risk of HCC. We found that the rs7574865 TT genotype was significantly associated with HBeAg seroconversion (TT vs. GG, p = 0.012; TT vs. GT, p = 0.033). The rs7574865 GG genotype was significantly associated with increased risks of CHB (p = 0.048), LC (p = 0.005) and HCC (p < 0.001). The interaction term between rs7574865 and HBV C1913A significantly increased the risk of progression from CHB to HCC (p = 0.038), while the interaction term between rs7574865 and HBV T1674C significantly increased the risk of progression from LC to HCC (p = 0.023). STAT4 rs7574865 is significantly associated with the risks of CHB, LC and HCC. The interactions of rs7574865 with HBV C1913A and T1674C mutations significantly increase the risk of HCC, which have the potential to identify HBV-infected individuals who tend to progress from CHB or LC to HCC.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Neoplasias Hepáticas , Fator de Transcrição STAT4 , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , Estudos de Casos e Controles , Predisposição Genética para Doença , Genótipo , Vírus da Hepatite B , Hepatite B Crônica/complicações , Hepatite B Crônica/genética , Humanos , Cirrose Hepática/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virologia , Mutação , Polimorfismo de Nucleotídeo Único , Fator de Transcrição STAT4/genética
17.
Front Immunol ; 13: 895762, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35844542

RESUMO

In kidney transplantation, deteriorated progression of rejection is considered to be a leading course of postoperative mortality. However, the conventional histologic diagnosis is limited in reading the rejection status at the molecular level, thereby triggering mismatched pathogenesis with clinical phenotypes. Here, by applying uniform manifold approximation and projection and Leiden algorithms to 2,611 publicly available microarray datasets of renal transplantation, we uncovered six rejection states with corresponding signature genes and revealed a high-risk (HR) state that was essential in promoting allograft loss. By identifying cell populations from single-cell RNA sequencing data that were associated with the six rejection states, we identified a T-cell population to be the pathogenesis-triggering cells associated with the HR rejection state. Additionally, by constructing gene regulatory networks, we identified that activated STAT4, as a core transcription factor that was regulated by PTPN6 in T cells, was closely linked to poor allograft function and prognosis. Taken together, our study provides a novel strategy to help with the precise diagnosis of kidney allograft rejection progression, which is powerful in investigating the underlying molecular pathogenesis, and therefore, for further clinical intervention.


Assuntos
Transplante de Rim , Insuficiência Renal , Fator de Transcrição STAT4 , Linfócitos T , Aloenxertos , Rejeição de Enxerto/genética , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/patologia , Humanos , Fator de Transcrição STAT4/genética , Fator de Transcrição STAT4/imunologia , Linfócitos T/imunologia , Transplante Homólogo
18.
Immunobiology ; 227(4): 152232, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35642993

RESUMO

Psoriatic Arthritis (PsA) is an immune-mediated rheumatic disease caused by the interaction between environmental factors and genetic predisposition. Many of the risk loci associated with PsA susceptibility are shared with other autoimmune diseases, suggesting an involvement of the same pathways in these diseases. We investigated the association between nine selected polymorphisms and PsA susceptibility and their possible role in the modulation of the disease activity. We analysed 163 patients with PsA and 298 age and sex-matched healthy subjects. Our results showed the associations of five polymorphisms with the disease development: rs33980500 (TRAF3IP2), rs6920220 (TNFAIP3), rs27524 (ERAP1), rs7574865 (STAT4) and rs1800872 (IL10). Patients carrying the variant allele of TRAF3IP2 polymorphism had a higher number of tender/swollen joints and a higher Disease Activity Index for PsA score. The multilocus genetic risk profile showed a higher probability to develop the disease in subjects with at least four risk alleles.


Assuntos
Artrite Psoriásica , RNA , Alelos , Aminopeptidases/genética , Artrite Psoriásica/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Genótipo , Humanos , Interleucina-10/genética , Antígenos de Histocompatibilidade Menor , Polimorfismo de Nucleotídeo Único , RNA/genética , Fator de Transcrição STAT4/genética , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética
19.
J Med Virol ; 94(9): 4449-4458, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35610746

RESUMO

A variant in signal transducer and activator of transcription 4 (STAT4) was reported to correlate with the response of interferon-α (IFN-α) in a retrospective study in hepatitis B e antigen (HBeAg)-positive chronic hepatitis B virus (CHB) patients. Here, we conducted a prospective study to analyze the effect of STAT4 genetic polymorphism on the response of pegylated interferon-α-2a (PegIFN-α-2a) in HBeAg-positive patients. A prospective, multicenter, open-label, parallel cohort study was performed. One hundred and fifty treatment-naïve and 156 nucleos(t)ide analog (NA)-experienced HBeAg-positive CHB patients were enrolled, respectively. All patients received PegIFN-α-2a treatment for 48 weeks and 24-week follow-up post PegIFN-α-2a treatment. Before treatment, STAT4 genetic polymorphism was determined by PCR and DNA sequencing. Serological markers, serum HBV DNA levels, and adverse events were collected at each visit. We observed a larger reduction of HBV DNA load and a significantly higher HBeAg seroconversion rate in the GT/TT group than in the GG group at week 72 (p = 0.002 and p = 0.023) in treatment-naïve patients. In NA-experienced patients, the HBeAg seroconversion rate in the GT/TT group was higher than that in the GG group at week 72 (p = 0.005). STAT4 rs7574865 gene polymorphism was the strongest independent predictor of HBeAg seroconversion in both paralleled cohorts. Also, patients in the GT/TT group had a higher hepatitis B surface antigen loss rate than in the GG group in the study. There was no significant difference in adverse events between GG and GT/TT groups. This prospective cohort study confirmed that STAT4 rs7574865 gene polymorphism is associated with HBeAg seroconversion and HBsAg loss irrespective of naïve and NA-experienced HBeAg-positive CHB patients treated with PegIFN-α-2a.


Assuntos
Antivirais , Hepatite B Crônica , Interferon-alfa , Fator de Transcrição STAT4 , Antivirais/uso terapêutico , Estudos de Coortes , DNA Viral , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , Hepatite B Crônica/tratamento farmacológico , Humanos , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Polimorfismo Genético , Estudos Prospectivos , Proteínas Recombinantes/uso terapêutico , Estudos Retrospectivos , Fator de Transcrição STAT4/genética , Soroconversão , Resultado do Tratamento
20.
J Immunol Res ; 2022: 8307280, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35528611

RESUMO

Objective: From our previous study, we obtained long noncoding RNA (lncRNA) STAT4-AS1, which is related to asthma through high-throughput screening. However, we could not determine the specific mechanism involved and in response to this. We further designed this study. Results: First, we found that lncRNA STAT4-AS1 was downregulated in T cells from patients with asthma when compared to healthy controls. Next, we confirmed that lncRNA STAT4-AS1 was significantly negatively correlated with T helper 17 (TH17) differentiation in vitro experiments. The decreases of STAT4-AS1 promoted TH17 differentiation, while the increases of STAT4-AS1 inhibited TH17 differentiation. Subsequently, through RNA pull-down, RNA-binding protein immunoprecipitation (RIP), and dual luciferase reporter assay, we found that STAT4-AS1 could inhibit the binding of retinoid-related orphan receptor-γt (RORγt) protein with an IL-17A promoter after binding with RORγt protein. Fluorescence in situ hybridization (FISH) and nuclear-cytoplasmic separation assay showed that STAT4-AS1 is bonded to RORγt in the cytoplasm, preventing RORγt from entering the nucleus. Conclusion: Overall, STAT4-AS1 directly targets RORγt protein, inhibits the mutual binding of RORγt and IL-17 gene promoter, and eventually inhibits TH17 differentiation. To this end, STAT4-AS1 as a potential target may confer applications in the clinical treatment and diagnosis of TH17-related diseases.


Assuntos
Asma , RNA Longo não Codificante , Asma/metabolismo , Diferenciação Celular/genética , Humanos , Hibridização in Situ Fluorescente , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proteínas de Ligação a RNA/genética , Fator de Transcrição STAT4/genética , Células Th17/metabolismo
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