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1.
Diabetes Obes Metab ; 25(11): 3223-3234, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37529870

RESUMO

AIM: To investigate the potential mechanism of once-weekly glucagon-like peptide-1 receptor agonists (GLP-1 RA) in the treatment of type 2 diabetes mellitus (T2DM) complicated with coronary artery disease (CAD). METHODS: We searched both Chinese and English databases for randomized controlled trials related to once-weekly GLP-1 RA for T2DM complicated with CAD to verify the safety and efficacy of GLP-1 RA. The underlying mechanism was analysed by network pharmacology. RESULTS: In total, 13 studies with 35 563 participants were included in the analysis. The pooled analysis found that dulaglutide, exenatide and semaglutide outperformed placebo in cardiovascular outcomes in patients with T2DM, with a significant reduction in the incidence of non-fatal stroke (p < .00). Levels of cardiovascular risk factors were significantly reduced in the once-weekly GLP-1 RA group compared with the conventional treatment group (glycated haemoglobin: p < .00; fasting blood glucose: p < .00; weight: p < .00; systolic blood pressure: p < .00; total cholesterol: p < .00; low-density lipoprotein cholesterol: p < .00). Network pharmacology results were enriched to the renin-angiotensin system, and matrix metalloproteinase 2 and renin (REN) may be the key targets. In addition, four key targets of dulaglutide, five key targets of exenatide and two key targets of semaglutide were enriched. CONCLUSIONS: Our study suggests that once-weekly GLP-1 RA may have a potential protective effect on cardiovascular events in patients with T2DM combined with CAD, possibly through the renin-angiotensin system. However, further research is needed to confirm these findings and determine cause and effect.


Assuntos
Doença da Artéria Coronariana , Diabetes Mellitus Tipo 2 , Receptor do Peptídeo Semelhante ao Glucagon 1 , Humanos , Colesterol , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Exenatida/uso terapêutico , Peptídeo 1 Semelhante ao Glucagon/uso terapêutico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Peptídeos Semelhantes ao Glucagon , Hipoglicemiantes/efeitos adversos , Metaloproteinase 2 da Matriz , Sistema Renina-Angiotensina
2.
Sci Transl Med ; 14(634): eabm0306, 2022 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-35235342

RESUMO

The CEACAM5 gene product [carcinoembryonic antigen (CEA)] is an attractive target for colorectal cancer because of its high expression in virtually all colorectal tumors and limited expression in most healthy adult tissues. However, highly active CEA-directed investigational therapeutics have been reported to be toxic, causing severe colitis because CEA is expressed on normal gut epithelial cells. Here, we developed a strategy to address this toxicity problem: the Tmod dual-signal integrator. CEA Tmod cells use two receptors: a chimeric antigen receptor (CAR) activated by CEA and a leukocyte Ig-like receptor 1 (LIR-1)-based inhibitory receptor triggered by human leukocyte antigen (HLA)-A*02. CEA Tmod cells exploit instances of HLA heterozygous gene loss in tumors to protect the patient from on-target, off-tumor toxicity. CEA Tmod cells potently killed CEA-expressing tumor cells in vitro and in vivo. But in contrast to a traditional CEA-specific T cell receptor transgenic T cell, Tmod cells were highly selective for tumor cells even when mixed with HLA-A*02-expressing cells. These data support further development of the CEA Tmod construct as a therapeutic candidate for colorectal cancer.


Assuntos
Neoplasias Colorretais , Receptores de Antígenos Quiméricos , Antígeno Carcinoembrionário/genética , Antígeno Carcinoembrionário/metabolismo , Terapia Baseada em Transplante de Células e Tecidos , Neoplasias Colorretais/genética , Neoplasias Colorretais/terapia , Antígeno HLA-A2/genética , Humanos , Perda de Heterozigosidade
3.
J Matern Fetal Neonatal Med ; 35(25): 9376-9382, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35105248

RESUMO

OBJECTIVE: To compare maternal outcomes of abnormally invasive placenta in China in 2012, 2015, and 2018, and further examine the association between use of abdominal aortic balloon occlusion (AABO) and the risk of maternal outcomes. MATERIALS AND METHODS: A retrospective analysis included 830 women diagnosed as abnormally invasive placenta from 5 tertiary care centers in China in 2012, 2015 and 2018. Participants were divided into AABO group and non-AABO group according to whether they were treated with AABO or not. Logistic regression models were used to assess the association of use of AABO with postpartum hemorrhage, blood transfusion, hysterectomy and repeated surgery. RESULTS: Among 830 participants, 66.0% (548/830) and 34.0% (282/830) of women were diagnosed with placenta increta and percreta, respectively; 33.3% (276/830) of women with abnormally invasive placenta were treated with AABO. In 2012, 2015, and 2018, the rate of blood transfusion was 83.1, 59.8, and 56.2%; the rate of hysterectomy was 50.8, 11.2, and 2.4%; and the rate of repeated surgery was 10.2, 9.4, and 0.9%. Use of AABO was associated with lower risk of postpartum hemorrhage (OR = 0.59, 95% CI: 0.35-0.99), blood transfusion (OR = 0.72, 95% CI: 0.52-0.99), hysterectomy (OR = 0.04, 95% CI: 0.01-0.14) and repeated surgery (OR = 0.14, 95% CI: 0.05-0.41) after adjustment for potential confounders. CONCLUSION: The rates of blood transfusion, hysterectomy and repeated surgery progressively decreased from 2012 to 2018 in Chinese women with abnormally invasive placenta. Use of AABO was associated with lower risk of postpartum hemorrhage, blood transfusion, hysterectomy and repeated surgery.


Assuntos
Oclusão com Balão , Placenta Acreta , Hemorragia Pós-Parto , Gravidez , Feminino , Humanos , Hemorragia Pós-Parto/epidemiologia , Hemorragia Pós-Parto/etiologia , Hemorragia Pós-Parto/terapia , Estudos Retrospectivos , Placenta Acreta/epidemiologia , Placenta Acreta/terapia , Placenta Acreta/diagnóstico , Histerectomia , Placenta , Perda Sanguínea Cirúrgica
4.
Toxicol Appl Pharmacol ; 437: 115894, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35085592

RESUMO

Cell therapy is an emerging therapeutic modality with the power to exploit new cancer targets and potentially achieve positive outcomes for patients with few other options. Like all synthetic treatments, cell therapy has the risk of toxicity via unpredicted off-target behavior. We describe an empirical method to model off-tumor, off-target reactivity of receptors used for investigational T cell therapies. This approach utilizes an optimal panel of diverse human cell-lines to capture the large majority of protein-coding gene expression in adult human tissues. We apply this cell-line set to test Jurkat and primary T cells engineered with a dual-signal integrator, called TmodTM, that contains an activating receptor (activator) and a separate inhibitory receptor (blocker). In proof-of-concept experiments, we use CD19 as the activating antigen and HLA-A*02 as the blocker antigen. This specific Tmod system, which employs a blocker targeting a ubiquitously expressed HLA class I antigen to inhibit CAR activation, has an inherent mechanism for selectivity/safety, designed to activate only when a specific HLA class I antigen is lost. Nonetheless, it is important to test off-target reactivity in functional assays, especially given the disconnect between ligand-binding and function among T cell receptors (TCRs) and chimeric antigen receptors (CARs). We show these cell-based assays yield consistent results with high sensitivity and specificity. The general strategy is likely applicable to more traditional single-receptor CAR- and TCR-T therapeutics.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/fisiologia , Antígenos CD19/genética , Antígenos CD19/metabolismo , Linhagem Celular Tumoral , Biologia Computacional , Deleção de Genes , Regulação da Expressão Gênica , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
5.
J Matern Fetal Neonatal Med ; 35(10): 1944-1950, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-32498575

RESUMO

OBJECTIVE: To compare conservative management and cesarean hysterectomy in patients with placenta increta or percreta. MATERIALS AND METHODS: In this multicenter retrospective study, we recorded data on 2219 patients with placenta increta or percreta from 20 tertiary care centers in China from 1 January 2011 to 31 December 2015. Propensity score analysis was used to control for baseline characteristics. We divided patients into conservative management (C) and hysterectomy (H) groups. The primary outcome was operative/postoperative maternal morbidity; secondary outcomes were maternal-neonatal outcomes. RESULTS: In total, 17.9% (398/2219) of patients had placenta increta and percreta; 82.1% (1821/2219) of the patients were in group C. After propensity score matching, 140 pairs of patients from the two groups underwent one-to-one matching. Group C showed less average blood loss within 24 h of surgery (1518 ± 1275 vs. 4309 ± 2550 ml in group H, p<.001). There were more patients with blood loss >1000 ml in group H than in group C (93.6% [131/140] vs. 61.4% [86/140], p<.001). More patients received blood transfusions in group H than in group C (p=.014). There was no significant difference between the groups in terms of bladder injury, postoperative anemia, fever, and disseminated intravascular coagulation. Neonatal outcomes in the two groups were similar. CONCLUSION: Either conservative management or hysterectomy should be considered after thorough evaluation and detailed discussion of risks and benefits. A balance between bleeding control and fertility can be achieved.


Assuntos
Placenta Acreta , Hemorragia Pós-Parto , Tratamento Conservador , Feminino , Humanos , Histerectomia , Recém-Nascido , Placenta Acreta/cirurgia , Hemorragia Pós-Parto/cirurgia , Gravidez , Estudos Retrospectivos
6.
J Immunother ; 44(8): 292-306, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34432728

RESUMO

Next-generation T-cell therapies will likely continue to utilize T-cell receptors (TCRs) and chimeric antigen receptors (CARs) because each receptor type has advantages. TCRs often possess exceptional properties even when tested unmodified from patients' T cells. CARs are generally less sensitive, possibly because their ligand-binding domains are grafted from antibodies selected for binding affinity or avidity and not broadly optimized for a functional response. Because of the disconnect between binding and function among these receptor types, the ultimate potential of CARs optimized for sensitivity and selectivity is not clear. Here, we focus on a thoroughly studied immuno-oncology target, the HLA-A*02/HPV-E629-38 complex, and show that CARs can be optimized by a combination of high-throughput binding screens and low-throughput functional assays to have comparable activity to clinical TCRs in acute assays in vitro. These results provide a case study for the challenges and opportunities of optimizing high-performing CARs, especially in the context of targets utilized naturally by TCRs.


Assuntos
Imunoterapia Adotiva , Neoplasias/terapia , Infecções por Papillomavirus/terapia , Receptores de Antígenos Quiméricos/imunologia , Linhagem Celular , Proteínas de Fluorescência Verde , Antígeno HLA-A2/imunologia , Humanos , Interferon gama/imunologia , Luciferases de Vaga-Lume , Neoplasias/imunologia , Proteínas Oncogênicas Virais/imunologia , Proteínas E7 de Papillomavirus/imunologia , Infecções por Papillomavirus/imunologia , Peptídeos/imunologia , Proteínas Repressoras/imunologia , Anticorpos de Cadeia Única/imunologia
7.
J Immunother ; 44(3): 95-105, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33284140

RESUMO

In 2013, an innovative MAGE-A3-directed cancer therapeutic of great potential value was terminated in the clinic because of neurotoxicity. The safety problems were hypothesized to originate from off-target T-cell receptor activity against a closely related MAGE-A12 peptide. A combination of published and new data led us to test this hypothesis with current technology. Our results call into question MAGE-A12 as the source of the neurotoxicity. Rather, the data imply that an alternative related peptide from EPS8L2 may be responsible. Given the qualities of MAGE-A3 as an onco-testis antigen widely expressed in tumors and largely absent from normal adult tissues, these findings suggest that MAGE-A3 may deserve further consideration as a cancer target. As a step in this direction, the authors isolated 2 MAGE-A3 peptide-major histocompatibility complex-directed chimeric antigen receptors, 1 targeting the same peptide as the clinical T-cell receptor. Both chimeric antigen receptors have improved selectivity over the EPS8L2 peptide that represents a significant risk for MAGE-A3-targeted therapeutics, showing that there may be other options for MAGE-A3 cell therapy.


Assuntos
Antígenos de Neoplasias/imunologia , Proteínas de Neoplasias/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Linhagem Celular , Linhagem Celular Tumoral , Células HCT116 , Células HEK293 , Humanos , Células Jurkat , Leucócitos Mononucleares/imunologia , Células MCF-7 , Complexo Principal de Histocompatibilidade/imunologia , Neoplasias/imunologia , Células PC-3 , Receptores de Antígenos Quiméricos/imunologia
8.
Mol Immunol ; 126: 56-64, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32768859

RESUMO

Chimeric antigen receptors (CARs) and their parent signaling molecule, the T cell receptor (TCR), are fascinating proteins of increasing relevance to disease therapy. Here we use a collection of 1221 pMHC-directed CAR constructs representing 10 pMHC targets to study aspects of CAR structure-activity relationships (SAR), with particular focus on the extracellular and transmembrane structural components. These experiments that involve pMHC targets whose number/cell can be manipulated by peptide dosing in vitro enable systematic analysis of the SAR of CARs in carefully controlled experimental situations (Harris and Kranz, 2016). We find that CARs tolerate a wide range of structural variation, with the ligand-binding domains (LBDs) dominating the SAR of CAR antigen sensitivity. Notwithstanding the critical role of the LBD, CAR antigen-binding on the cell surface, measured by pMHC tetramer staining, is not an effective predictor of functional sensitivity. These results have important implications for the design and testing of CARs aimed toward the clinic.


Assuntos
Antígenos HLA-A/imunologia , Receptores de Antígenos Quiméricos/metabolismo , Transdução de Sinais/imunologia , Linfócitos T/imunologia , Sítios de Ligação/imunologia , Antígenos HLA-A/metabolismo , Humanos , Células Jurkat , Ligantes , Células MCF-7 , Domínios Proteicos/imunologia , Multimerização Proteica/imunologia , Receptores de Antígenos Quiméricos/imunologia , Relação Estrutura-Atividade , Linfócitos T/metabolismo
9.
J Nat Prod ; 83(5): 1374-1382, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32401511

RESUMO

The distinctive nature of the endophyte Irpex lacteus, host plant, and the phytopathogen Collectotrichum gloeosporioides resulted in both negative and positive regulation of the production of phytotoxins from Nigrospora oryzae. The coculture of nonhomologous I. lacteus and N. oryzae resulted in a greater number of anti-phytopathogenic metabolites from the dominant endophyte than the coculture of homologous I. lacteus and N. oryzae. The coculture of the phytopathogen N. oryzae and either the nonhomologous (isolation of I. lacteus and N. oryzae from the different plants) or homologous (isolation of I. lacteus and N. oryzae from the same plant) endophyte I. lacteus from different sources indicated that the nonhomologous I. lacteus grew faster than the homologous I. lacteus, and the production of phytotoxic azaphilone from the phytopathogenic N. oryzae decreased due to the inhibition resulting from being cocultured with nonhomologous I. lacteus. On the other hand, the production of phytotoxic azaphilone was promoted by the coculture of two phytopathogens, N. oryzae and C. gloeosporioides. The extract of the host plant, Dendrobium officinale, also increased anti-phytopathogenic metabolite production. Six new phytotoxic azaphilones from N. oryzae, four new tremulane sesquiterpenes from I. lacteus, and a new polyketone were isolated. The endophyte-phytopathogen, phytopathogen-phytopathogen, and endophyte-phytopathogen-host interactions can induce the chemical diversity of novel anti-phytopathogenic metabolites.


Assuntos
Ascomicetos/metabolismo , Dendrobium/microbiologia , Dendrobium/toxicidade , Polyporales/metabolismo , Antifúngicos/farmacologia , Ascomicetos/efeitos dos fármacos , Benzopiranos , Técnicas de Cocultura , Endófitos , Cetonas/farmacologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Pigmentos Biológicos/biossíntese , Doenças das Plantas/microbiologia , Polyporales/efeitos dos fármacos , Sesquiterpenos/farmacologia
10.
Nucleic Acids Res ; 48(6): 2969-2981, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-32043141

RESUMO

Polycomb repressive complex 2 (PRC2) is a histone methyltransferase that methylates histone H3 at Lysine 27. PRC2 is critical for epigenetic gene silencing, cellular differentiation and the formation of facultative heterochromatin. It can also promote or inhibit oncogenesis. Despite this importance, the molecular mechanisms by which PRC2 compacts chromatin are relatively understudied. Here, we visualized the binding of PRC2 to naked DNA in liquid at the single-molecule level using atomic force microscopy. Analysis of the resulting images showed PRC2, consisting of five subunits (EZH2, EED, SUZ12, AEBP2 and RBBP4), bound to a 2.5-kb DNA with an apparent dissociation constant ($K_{\rm{D}}^{{\rm{app}}}$) of 150 ± 12 nM. PRC2 did not show sequence-specific binding to a region of high GC content (76%) derived from a CpG island embedded in such a long DNA substrate. At higher concentrations, PRC2 compacted DNA by forming DNA loops typically anchored by two or more PRC2 molecules. Additionally, PRC2 binding led to a 3-fold increase in the local bending of DNA's helical backbone without evidence of DNA wrapping around the protein. We suggest that the bending and looping of DNA by PRC2, independent of PRC2's methylation activity, may contribute to heterochromatin formation and therefore epigenetic gene silencing.


Assuntos
DNA/química , Imageamento Tridimensional , Microscopia de Força Atômica , Conformação de Ácido Nucleico , Complexo Repressor Polycomb 2/metabolismo , Humanos , Ligação Proteica , Multimerização Proteica
11.
Nat Prod Res ; 34(21): 3101-3107, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31111733

RESUMO

Red ginseng (RG) is one of the most popular herbal medicines and used as a dietary supplement in recent years. The bioactive ingredient in RG can induce the production of novel microbial metabolite from fermented RG. Using the one strain-many compounds strategy, the reinvestigation of the metabolites from Daldinia eschscholzii JC-15 cultured in red ginseng medium led to the isolation of an unprecedented benzopyran-naphthalene hybrid, daldinsin (1) and a new lactone (2). In this research, a new lactone, 8-hydroxylhelicascolide A (2) instead of helicascolide A was produced by the D. eschscholzii JC-15 induced by the red ginseng medium. Compound 1 showed anti-acetylcholinesterase activity with the inhibition ratio of 38.8% at 50 µM. Compound 2 indicated antimicrobial activities against Fusarium Solani, F. oxysporum, and Escherichia coli with MICs at 128 µg/mL. RG is therefore a promising activator in production of novel microbial metabolite.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Panax/química , Xylariales/efeitos dos fármacos , Xylariales/metabolismo , Células 3T3-L1 , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Inibidores da Colinesterase/química , Inibidores da Colinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Meios de Cultura/farmacologia , Avaliação Pré-Clínica de Medicamentos , Escherichia coli/efeitos dos fármacos , Fermentação , Fusarium/efeitos dos fármacos , Humanos , Lactonas/metabolismo , Lactonas/farmacologia , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Metabolismo Secundário
12.
Asia Pac J Public Health ; 31(7): 652-658, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31578073

RESUMO

Background. To explore the feasibility of careHPV (human papillomavirus) with cytology triage as a cervical cancer screening in rural areas of China. Methods. A total of 7138 women aged 35 to 64 years were divided into 2 groups. Women in careHPV group (n = 3536) underwent careHPV and 288 positive subjects underwent cytology, of which 65 women were ≥ASC-US (atypical squamous cells of undetermined significance). Women in the cytology group (n = 3602) underwent cytology and 111 women were ≥ASC-US. All subjects with ≥ASC-US were referred to colposcopy and biopsy. Results. The average age of subjects was 48.2 ± 7.8 years. In the careHPV group, the HPV-positive rate was 8.1%. The detection rate of ≥ASC-US was 1.8% in the careHPV group and 3.1% in the cytology group (P = .001). There was no significant difference in detection rate of ≥CINII (cervical intraepithelial neoplasia) in the careHPV group (0.7%) and the cytology group (0.6%; P = .416). In addition, to identify 1 case ≥CINII, an average of 2.6 colposcopies were needed in the careHPV group, and 5.3 colposcopies were performed to diagnose 1 case ≥CINII in the cytology group. Conclusions. careHPV with cytology triage offered similar efficiency in identifying abnormalities of CINII and above compared with cytology screening. With the reduced requirement for cytology testing and colposcopy, careHPV may be a more favorable cervical cancer screening strategy in areas of China where there is a lack of cytology services.


Assuntos
Detecção Precoce de Câncer/métodos , População Rural , Neoplasias do Colo do Útero/diagnóstico , Adulto , Biologia Celular , China , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , População Rural/estatística & dados numéricos , Sensibilidade e Especificidade
13.
Nat Struct Mol Biol ; 24(12): 1028-1038, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29058709

RESUMO

Many studies have revealed pathways of epigenetic gene silencing by Polycomb repressive complex 2 (PRC2) in vivo, but understanding the underlying molecular mechanisms requires biochemistry. Here we analyze interactions of reconstituted human PRC2 with nucleosome complexes. Histone modifications, the H3K27M cancer mutation, and inclusion of JARID2 or EZH1 in the PRC2 complex have unexpectedly minor effects on PRC2-nucleosome binding. Instead, protein-free linker DNA dominates the PRC2-nucleosome interaction. Specificity for CG-rich sequences is consistent with PRC2 occupying CG-rich DNA in vivo. PRC2 preferentially binds methylated DNA regulated by its AEBP2 subunit, suggesting how DNA and histone methylation collaborate to repress chromatin. We find that RNA, known to inhibit PRC2 activity, is not a methyltransferase inhibitor per se. Instead, RNA sequesters PRC2 from nucleosome substrates, because PRC2 binding requires linker DNA, and RNA and DNA binding are mutually exclusive. Together, we provide a model for PRC2 recruitment and an explanation for how actively transcribed genomic regions bind PRC2 but escape silencing.


Assuntos
Cromatina/genética , Proteínas de Ligação a DNA/genética , Inativação Gênica/fisiologia , Complexo Repressor Polycomb 2/genética , RNA/metabolismo , Composição de Bases/genética , Linhagem Celular , DNA/metabolismo , Metilação de DNA/genética , Epigênese Genética/genética , Histonas/genética , Histonas/metabolismo , Humanos , Nucleossomos/metabolismo , Ligação Proteica/genética , Proteínas Repressoras/metabolismo
14.
Int J Mol Med ; 39(3): 764-770, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28204810

RESUMO

Human T cell leukemia virus type 1 (HTLV-1) is an oncogenic retrovirus. It can cause adult T cell leukemia (ATL) and other diseases. The HTLV-1 basic leucine zipper (bZIP) factor (HBZ), which is encoded by the minus-strand of the provirus, is expressed in all cases of ATL and involved in T cell proliferation. However, the exact mechanism underlying its growth-promoting activity is poorly understood. Herein, we demonstrated that HBZ suppressed cyclin D1 expression by inhibiting the nuclear factor (NF)-κB signaling pathway. Among the potential mechanisms of cyclin D1 inhibition mediated by HBZ, we found that HBZ suppressed cyclin D1 promoter activity. Luciferase assay analysis revealed that HBZ repressed cyclin D1 promoter activity by suppressing NF-κB­driven transcription mediated by the p65 subunit. Using an immunoprecipitation assay, we found that HBZ could bind to p65, but not p50. Finally, we showed that HBZ selectively interacted with p65 via its AD+bZIP domains. By suppressing cyclin D1 expression, HBZ can alter cell cycle progression of HTLV-1-infected cells, which may be critical for oncogenesis.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Ciclina D1/genética , Regulação da Expressão Gênica , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , NF-kappa B/metabolismo , Proteínas dos Retroviridae/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/química , Linhagem Celular , Ordem dos Genes , Vetores Genéticos/genética , Humanos , Zíper de Leucina , Regiões Promotoras Genéticas , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Proteínas dos Retroviridae/química , Ativação Transcricional
15.
Oncotarget ; 8(64): 107346-107347, 2017 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-29296169
16.
Nucleic Acids Res ; 43(15): 7535-43, 2015 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-26150427

RESUMO

FUS, a nuclear RNA-binding protein, plays multiple roles in RNA processing. Five specific FUS-binding RNA sequence/structure motifs have been proposed, but their affinities for FUS have not been directly compared. Here we find that human FUS binds all these sequences with Kd (app) values spanning a 10-fold range. Furthermore, some RNAs that do not contain any of these motifs bind FUS with similar affinity. FUS binds RNA in a length-dependent manner, consistent with a substantial non-specific component to binding. Finally, investigation of FUS binding to different nucleic acids shows that it binds single-stranded DNA with three-fold lower affinity than ssRNA of the same length and sequence, while binding to double-stranded nucleic acids is weaker. We conclude that FUS has quite general nucleic acid-binding activity, with the various proposed RNA motifs being neither necessary for FUS binding nor sufficient to explain its diverse binding partners.


Assuntos
Proteína FUS de Ligação a RNA/metabolismo , RNA/metabolismo , DNA/metabolismo , DNA de Cadeia Simples/metabolismo , Humanos , Motivos de Nucleotídeos , Ligação Proteica , RNA/química
17.
Mol Cell ; 57(3): 552-8, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25601759

RESUMO

Polycomb repressive complex-2 (PRC2) is a histone methyltransferase required for epigenetic silencing during development and cancer. Early works suggested binding specificity of PRC2 to certain long non-coding RNAs for recruitment to chromatin. More recent studies provided evidence both in favor and against this idea. Here, we bridge the two existing models of PRC2-RNA interaction. RepA RNA is a good binding partner for PRC2, while multiple non-relevant RNAs, including bacterial mRNAs, also bind PRC2; Kds depend to some extent on the experimental conditions. Human and mouse PRC2 have broadly similar RNA-binding properties in vitro. Examination of evidence supporting an existing model for site-specific recruitment of PRC2 by a well-defined RNA motif in cells reveals that results are PRC2 independent. We conclude that promiscuous and specific RNA-binding activities of PRC2 in vitro are not mutually exclusive, and that binding specificity in vivo remains to be demonstrated.


Assuntos
Complexo Repressor Polycomb 2/metabolismo , Ligação Proteica , RNA/metabolismo , Animais , Células HEK293 , Humanos , Técnicas In Vitro , Sequências Repetidas Invertidas , Camundongos , RNA/química , RNA Longo não Codificante/metabolismo
18.
Genet Test Mol Biomarkers ; 18(11): 761-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25325233

RESUMO

BACKGROUND: Numerous genetic risk factors of ischemic stroke (IS) have been reported from both candidate gene and genome-wide strategies with inconsistent results. The objective of this study was to confirm the relationship between 10 previously identified single-nucleotide polymorphisms (SNPs) and IS in the Chinese population. METHODS: A family-based study was conducted in a rural area of Beijing, with a total of 227 IS families with 622 participants recruited. Both linkage and association analyses were performed, with all the sibling pairs derived from the 227 families analyzed using the sib-pair test of model-free linkage to assess linkage between SNPs and IS, with association analyses including a family-based association test (FBAT) and generalized estimating equations (GEE). RESULTS: Nonparametric linkage analysis revealed that the rs1800796 polymorphism in the interleukin-6 (IL-6) gene is significantly linked to the small arterial occlusion (SAO) subtype (p=0.022), while the rs7193343 polymorphism in the ZFHX3 gene is linked to IS (p=0.002) under the dominant model. Significant allelic associations were identified between the G allele of rs1800796 and IS (p=0.042) and the SAO subtype (p=0.025) in the FBAT. The GEE method revealed that the G allele of rs1800796 increased IS risk by 1.55-fold (95% 95% confidence interval [CI]: 1.01, 2.37; p=0.043) and 2.43-fold (95% CI: 1.32, 4.45; p=0.004) in the SAO subtype in the dominant model, which correlated with the significant associations detected in the FBAT. CONCLUSIONS: In this study, we confirmed that the SNP of rs1800796 in the IL-6 gene is related to IS and the SAO subtype using different statistical approaches. These findings could contribute to identifying individuals with a high IS risk.


Assuntos
Isquemia Encefálica/genética , Família , Ligação Genética , Interleucina-6/genética , Polimorfismo de Nucleotídeo Único , Acidente Vascular Cerebral/genética , Adulto , Alelos , Povo Asiático , China , Feminino , Humanos , Masculino , Fatores de Risco
19.
J Thromb Thrombolysis ; 38(4): 470-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24664524

RESUMO

Novel susceptibility genes related to ischemic stroke (IS) are proposed in recent literatures. Population-based replicate studies would cause false positive results due to population stratification. 229 recruit IS patients and their 229 non-IS siblings were used in this study to avoid population stratification. The family-based study was conducted in Beijing from June 2005 to June 2012. Association between SNPs and IS was found in the sibship discordant tests, and the conditional logistic regression was performed to identify effect size and explore gene-environment interactions. Significant allelic association was identified between NINJ2 gene rs11833579 (P = 0.008), protein kinase C η gene rs2230501 (P = 0.039) and IS. The AA genotype of rs11833579 increased 1.51-fold risk (95% CI 1.04-3.46; P = 0.043) of IS, and it conferred susceptibility to IS only in a dominant model (OR 2.69; 95% CI 1.06-6.78; P = 0.036]. Risk of IS was higher (HR 3.58; 95% CI 1.54-8.31; P = 0.003) especially when the carriers of rs11833579 AA genotype were smokers. The present study suggests A allele of rs11833579 may play a role in mediating susceptibility to IS and it may increase the risk of IS together with smoking.


Assuntos
Isquemia Encefálica/genética , Moléculas de Adesão Celular Neuronais/genética , Estudos de Associação Genética/métodos , Polimorfismo de Nucleotídeo Único/genética , Irmãos , Acidente Vascular Cerebral/genética , Idoso , Isquemia Encefálica/diagnóstico , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fumar/efeitos adversos , Fumar/genética , Acidente Vascular Cerebral/diagnóstico
20.
Cell Rep ; 5(4): 918-25, 2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24268778

RESUMO

The abundant nuclear RNA binding protein FUS binds the C-terminal domain (CTD) of RNA polymerase II in an RNA-dependent manner, affecting Ser2 phosphorylation and transcription. Here, we examine the mechanism of this process and find that RNA binding nucleates the formation of higher-order FUS ribonucleoprotein assemblies that bind the CTD. Both the low-complexity domain and the arginine-glycine rich domain of FUS contribute to assembly. The assemblies appear fibrous by electron microscopy and have characteristics of ß zipper structures. These results support the emerging view that the pathologic protein aggregation seen in neurodegenerative diseases such as amyotrophic lateral sclerosis may occur via the exaggeration of functionally important assemblies of RNA binding proteins.


Assuntos
RNA Polimerase II/metabolismo , Proteína FUS de Ligação a RNA/metabolismo , RNA/genética , Esclerose Lateral Amiotrófica/genética , Linhagem Celular , DNA (Citosina-5-)-Metiltransferases/genética , Células HEK293 , Humanos , Regiões Promotoras Genéticas , Ligação Proteica , Estrutura Terciária de Proteína , Proteína FUS de Ligação a RNA/biossíntese , Proteína FUS de Ligação a RNA/genética , Ribonucleoproteínas/biossíntese , Ribonucleoproteínas/genética , Ribonucleoproteínas/metabolismo , Transcrição Gênica , DNA Metiltransferase 3B
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