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1.
Nat Immunol ; 20(7): 835-851, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31160797

RESUMO

How tumor cells genetically lose antigenicity and evade immune checkpoints remains largely elusive. We report that tissue-specific expression of the human long noncoding RNA LINK-A in mouse mammary glands initiates metastatic mammary gland tumors, which phenotypically resemble human triple-negative breast cancer (TNBC). LINK-A expression facilitated crosstalk between phosphatidylinositol-(3,4,5)-trisphosphate and inhibitory G-protein-coupled receptor (GPCR) pathways, attenuating protein kinase A-mediated phosphorylation of the E3 ubiquitin ligase TRIM71. Consequently, LINK-A expression enhanced K48-polyubiquitination-mediated degradation of the antigen peptide-loading complex (PLC) and intrinsic tumor suppressors Rb and p53. Treatment with LINK-A locked nucleic acids or GPCR antagonists stabilized the PLC components, Rb and p53, and sensitized mammary gland tumors to immune checkpoint blockers. Patients with programmed ccll death protein-1(PD-1) blockade-resistant TNBC exhibited elevated LINK-A levels and downregulated PLC components. Hence we demonstrate lncRNA-dependent downregulation of antigenicity and intrinsic tumor suppression, which provides the basis for developing combinational immunotherapy treatment regimens and early TNBC prevention.


Assuntos
Apresentação de Antígeno/imunologia , Regulação Neoplásica da Expressão Gênica , Neoplasias/genética , Neoplasias/imunologia , Oncogenes , RNA Longo não Codificante/genética , Evasão Tumoral/genética , Evasão Tumoral/imunologia , Adenoma/genética , Adenoma/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Humanos , Camundongos , Neoplasias/metabolismo , Neoplasias/patologia , Fosforilação , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Proteína Supressora de Tumor p53/metabolismo , Ubiquitinação , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Cell ; 159(5): 1110-1125, 2014 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-25416949

RESUMO

lncRNAs are known to regulate a number of different developmental and tumorigenic processes. Here, we report a role for lncRNA BCAR4 in breast cancer metastasis that is mediated by chemokine-induced binding of BCAR4 to two transcription factors with extended regulatory consequences. BCAR4 binding of SNIP1 and PNUTS in response to CCL21 releases the SNIP1's inhibition of p300-dependent histone acetylation, which in turn enables the BCAR4-recruited PNUTS to bind H3K18ac and relieve inhibition of RNA Pol II via activation of the PP1 phosphatase. This mechanism activates a noncanonical Hedgehog/GLI2 transcriptional program that promotes cell migration. BCAR4 expression correlates with advanced breast cancers, and therapeutic delivery of locked nucleic acids (LNAs) targeting BCAR4 strongly suppresses breast cancer metastasis in mouse models. The findings reveal a disease-relevant lncRNA mechanism consisting of both direct coordinated protein recruitment and indirect regulation of transcription factors.


Assuntos
Neoplasias da Mama/metabolismo , Metástase Neoplásica , RNA Longo não Codificante/metabolismo , Animais , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Epigênese Genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Camundongos , Proteínas Nucleares/metabolismo , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais , Ativação Transcricional , Proteína Gli2 com Dedos de Zinco , Fatores de Transcrição de p300-CBP/metabolismo
3.
Mol Cell ; 75(1): 13-25.e5, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31151856

RESUMO

Arc is a synaptic protein essential for memory consolidation. Recent studies indicate that Arc originates in evolution from a Ty3-Gypsy retrotransposon GAG domain. The N-lobe of Arc GAG domain acquired a hydrophobic binding pocket in higher vertebrates that is essential for Arc's canonical function to weaken excitatory synapses. Here, we report that Arc GAG also acquired phosphorylation sites that can acutely regulate its synaptic function. CaMKII phosphorylates the N-lobe of the Arc GAG domain and disrupts an interaction surface essential for high-order oligomerization. In Purkinje neurons, CaMKII phosphorylation acutely reverses Arc's synaptic action. Mutant Arc that cannot be phosphorylated by CaMKII enhances metabotropic receptor-dependent depression in the hippocampus but does not alter baseline synaptic transmission or long-term potentiation. Behavioral studies indicate that hippocampus- and amygdala-dependent learning requires Arc GAG domain phosphorylation. These studies provide an atomic model for dynamic and local control of Arc function underlying synaptic plasticity and memory.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteínas do Citoesqueleto/metabolismo , Potenciação de Longa Duração/fisiologia , Memória/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Células de Purkinje/metabolismo , Sequência de Aminoácidos , Tonsila do Cerebelo/citologia , Tonsila do Cerebelo/metabolismo , Animais , Sítios de Ligação , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/química , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/genética , Técnicas de Introdução de Genes , Células HEK293 , Hipocampo/citologia , Hipocampo/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Moleculares , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/genética , Fosforilação , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Células de Purkinje/citologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Sinapses/fisiologia , Transmissão Sináptica
4.
Cell ; 147(4): 773-88, 2011 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-22078878

RESUMO

Although eukaryotic nuclei contain distinct architectural structures associated with noncoding RNAs (ncRNAs), their potential relationship to regulated transcriptional programs remains poorly understood. Here, we report that methylation/demethylation of Polycomb 2 protein (Pc2) controls relocation of growth-control genes between Polycomb bodies (PcGs) and interchromatin granules (ICGs) in response to growth signals. This movement is the consequence of binding of methylated and unmethylated Pc2 to the ncRNAs TUG1 and MALAT1/NEAT2, located in PcGs and ICGs, respectively. These ncRNAs mediate assembly of multiple corepressors/coactivators and can serve to switch mark recognition by "readers" of the histone code. Additionally, binding of NEAT2 to unmethylated Pc2 promotes E2F1 SUMOylation, leading to activation of the growth-control gene program. These observations delineate a molecular pathway linking the actions of subnuclear structure-specific ncRNAs and nonhistone protein methylation to relocation of transcription units in the three-dimensional space of the nucleus, thus achieving coordinated gene expression programs.


Assuntos
Núcleo Celular/metabolismo , Regulação da Expressão Gênica , RNA não Traduzido/metabolismo , Proteínas Repressoras/metabolismo , Sequência de Aminoácidos , Linhagem Celular , Cromatina/metabolismo , Fator de Transcrição E2F1/metabolismo , Células HeLa , Humanos , Ligases , Metilação , Metiltransferases/metabolismo , Dados de Sequência Molecular , Proteínas do Grupo Polycomb , RNA Longo não Codificante , Proteínas Repressoras/química , Sumoilação , Transcrição Gênica , Ubiquitina-Proteína Ligases , Ubiquitinação
5.
Circ Res ; 133(7): 572-587, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37641975

RESUMO

BACKGROUND: A better understanding of the regulation of proteasome activities can facilitate the search for new therapeutic strategies. A cell culture study shows that PKA (cAMP-dependent protein kinase or protein kinase A) activates the 26S proteasome by pS14-Rpn6 (serine14-phosphorylated Rpn6), but this discovery and its physiological significance remain to be established in vivo. METHODS: Male and female mice with Ser14 of Rpn6 (regulatory particle non-ATPase 6) mutated to Ala (S14A [Rpn6/Psmd11S14A]) or Asp (S14D) to respectively block or mimic pS14-Rpn6 were created and used along with cells derived from them. cAMP/PKA were manipulated pharmacologically. Ubiquitin-proteasome system functioning was evaluated with the GFPdgn (green fluorescence protein with carboxyl fusion of the CL1 degron) reporter mouse and proteasomal activity assays. Impact of S14A and S14D on proteotoxicity was tested in mice and cardiomyocytes overexpressing the misfolded protein R120G-CryAB (R120G [arginine120 to glycine missense mutant alpha B-crystallin]). RESULTS: PKA activation increased pS14-Rpn6 and 26S proteasome activities in wild-type but not S14A embryonic fibroblasts (mouse embryonic fibroblasts), adult cardiomyocytes, and mouse hearts. Basal 26S proteasome activities were significantly greater in S14D myocardium and adult mouse cardiomyocytes than in wild-type counterparts. S14D::GFPdgn mice displayed significantly lower myocardial GFPdgn protein but not mRNA levels than GFPdgn mice. In R120G mice, a classic model of cardiac proteotoxicity, basal myocardial pS14-Rpn6 was significantly lower compared with nontransgenic littermates, which was not always associated with reduction of other phosphorylated PKA substrates. Cultured S14D neonatal cardiomyocytes displayed significantly faster proteasomal degradation of R120G than wild-type neonatal cardiomyocytes. Compared with R120G mice, S14D/S14D::R120G mice showed significantly greater myocardial proteasome activities, lower levels of total and K48-linked ubiquitin conjugates, and of aberrant CryAB (alpha B-crystallin) protein aggregates, less fetal gene reactivation, and cardiac hypertrophy, and delays in cardiac malfunction. CONCLUSIONS: This study establishes in animals that pS14-Rpn6 mediates the activation of 26S proteasomes by PKA and that the reduced pS14-Rpn6 is a key pathogenic factor in cardiac proteinopathy, thereby identifying a new therapeutic target to reduce cardiac proteotoxicity.


Assuntos
Complexo de Endopeptidases do Proteassoma , Cadeia B de alfa-Cristalina , Feminino , Masculino , Animais , Camundongos , Fibroblastos , Miócitos Cardíacos , Proteínas Quinases Dependentes de AMP Cíclico , Ubiquitinas
6.
Gastroenterology ; 164(4): 630-641.e34, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36623778

RESUMO

BACKGROUND & AIMS: The etiology of abdominal pain in postinfectious, diarrhea-predominant irritable bowel syndrome (PI-IBS-D) is unknown, and few treatment options exist. Catechol-O-methyltransferase (COMT), an enzyme that inactivates and degrades biologically active catecholamines, plays an important role in numerous physiologic processes, including modulation of pain perception. Our objective was to determine the mechanism(s) of how decreased colonic COMT in PI-IBS-D patients contributes to the chronic abdominal pain phenotype after enteric infections. METHODS: Colon neurons, epithelial cells, and macrophages were procured with laser capture microdissection from PI-IBS-D patients to evaluate cell-specific colonic COMT, microRNA-155 (miR-155), and tumor necrosis factor (TNF) α expression levels compared to recovered patients (infection cleared: did not develop PI-IBS-D) and control individuals. COMT-/-, colon-specific COMT-/-, and miR-155-/- mice and human colonoids were used to model phenotypic expression of COMT in PI-IBS-D patients and to investigate signaling pathways linking abdominal pain. Citrobacter rodentium and trinitrobenzene sulfonic acid animal models were used to model postinflammatory changes seen in PI-IBS-D patients. RESULTS: Colonic COMT levels were significantly decreased and correlated with increased visual analog scale abdominal pain ratings in PI-IBS-D patients compared to recovered patients and control individuals. Colonic miR-155 and TNF-α were increased in PI-IBS-D patients with diminished colonic COMT. COMT-/- mice had significantly increased expression of miR-155 and TNF-α in both colon tissues and dorsal root ganglia. Introduction of cV1q antibody (anti-TNF-α) into mice reversed visceral hypersensitivity after C rodentium and trinitrobenzene sulfonic acid. CONCLUSIONS: Decreased colonic COMT in PI-IBS-D patients drives abdominal pain phenotypes via the COMT/miR-155/TNF-α axis. These important findings will allow new treatment paradigms and more targeted and personalized medicine approaches for gastrointestinal disorders after enteric infections.


Assuntos
Síndrome do Intestino Irritável , MicroRNAs , Humanos , Camundongos , Animais , Síndrome do Intestino Irritável/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Catecol O-Metiltransferase/genética , Catecol O-Metiltransferase/metabolismo , Nociceptividade , Inibidores do Fator de Necrose Tumoral , Colo/metabolismo , Dor Abdominal/genética , Dor Abdominal/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Trinitrobenzenos/metabolismo , Ácidos Sulfônicos/metabolismo
7.
Small ; 20(2): e2304878, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37691015

RESUMO

Dual-salt magnesium/lithium-ion batteries (MLIBs) benefit from fast lithium ion diffusion on the cathode side while providing safety due to the dendrite-free Mg2+ stripping/plating mechanism on the anode side. Bulk MoS2 (B-MoS2 ), as a cathode for magnesium-ion batteries (MIBs), suffers from low conductivity and relatively van der Waals gaps and, consequently, resists against divalent Mg2+ insertion due to the high Coulombic interactions. In MLIBs, it exhibits a Daniell-cell type mechanism with the sole accommodation of Li+ . In this paper, the synthesis of a 1T/2H mixed-phase MoS2 (MP-MoS2 ) modified with a hyperbranched polyethylene ionomer, I@MP-MoS2 , for high-capacity MLIBs with a distinct Mg2+ /Li+ co-intercalation mechanism is reported. Benefiting from the enhanced conductivity (due to 53% metallic 1T phase), expanded van der Waals gaps (79% expansion compared to B-MoS2 , 1.11 vs 0.62 nm), and enhanced interactions with THF-based electrolytes following the modification, I@MP-MoS2 shows a dramatically increased Mg2+ storage compared to its parent analogue (144 mAh g-1 vs ≈2 mAh g-1 at 20 mA g-1 ). In MLIBs, I@MP-MoS2 is demonstrated to exhibit remarkable specific capacities up to ≈270 mAh g-1 at 20 mA g-1 through a Mg2+ /Li+ co-intercalation mechanism with 87% of capacity retention over 200 cycles at 100 mA g-1 .

8.
Small ; : e2400541, 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38644221

RESUMO

The high crystalline covalent triazine framework-1 (CTF-1), composed of alternating triazine and phenylene, has emerged as an efficient photocatalyst for solar-driven hydrogen evolution reaction (HER). However, it is of great challenge to further improve photocatalytic HER performance via increasing crystallinity due to its near-perfect crystallization. Herein, an alternative strategy of scaffold functionalization is employed to optimize the energy band structure of crystalline CTF-1 for boosting hydrogen-evolving activity. Guided by the computational predictions, versatile CTF-based polymer photocatalysts are prepared with different functional groups (OH, NH2, COOH) using binary polymerization for practical hydrogen production. Experiment evidence verifies that the introduction of a limited number of electron-donating groups is sufficient to maintain high crystallinity in CTF, modulate the band structure, broaden visible light absorption, and consequently enhance its photophysical properties. Notably, the functionalization with OH exhibits the most positive effect on CTF-1, delivering a photocatalytic activity with a hydrogen-producing rate exceeding 100 µmol h-1.

9.
J Med Virol ; 96(1): e29338, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38163280

RESUMO

Monkeypox (mpox), a viral zoonotic disease, is spreading worldwide. However, evidence that informs prevention and control strategies in the Asia Pacific Region is very limited. Our study aims to investigate the experiences of mpox patients from infection to treatment to provide scientific basis for the prevention and control. A multicenter qualitative design was used. A total of 15 mpox patients were recruited between July 6 and July 25, 2023, from six cities in China. Semistructured interviews were conducted by telephone and analyzed using the thematic analysis. The interview was divided into two sections: patients' experiences (prediagnosis experience, treatment-seeking experience, and quarantine experience) and advice. Prediagnosis experience was summarized into three themes: symptoms, possible routes of infection, and knowledge of mpox. Treatment-seeking experience was summarized into three themes: time of visit to hospital, diagnostic difficulties, and attitude toward diagnosis. Quarantine experience was summarized into three themes: body and mind reactions, reluctance to self-disclose infection status, and factors facilitating recovery. Themes identified from patients' advice were as follows: (1) Increase in testing channels and methods, (2) Development and introduction of vaccines, (3) Adjustment of quarantine program, (4) Improvement of treatment measures, and (5) Improvement of publicity and education. To effectively curb the mpox epidemic, structured measures are urgently needed to address the mpox-related stigma and discrimination. Targeted health education should be provided to MSM, focusing on the prevention, detection, and treatment services. Hospitals should enhance the training of clinicians in key departments including infectious disease and dermatology, to improve diagnostic capability and sensitivity. Furthermore, given the absence of specific antiviral medications, supervised home quarantine may be a good option.


Assuntos
Mpox , Humanos , China/epidemiologia , Ásia , Antivirais , Cidades
10.
Chem Res Toxicol ; 37(5): 731-743, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38634348

RESUMO

Acrylamide (ACR) is a common industrial contaminant with endocrine-disrupting toxicity. Numerous studies have indicated that females and diabetics are more sensitive to environmental contaminants. However, it remains unknown whether female diabetics are susceptible to ACR-induced toxicity and its potential mechanisms. Thus, the female ACR-exposure diabetic Balb/c mice model was established to address these issues. Results showed that ACR could induce liver injury in normal mice and cause more serious inflammatory cell infiltration, hepatocyte volume increase, and fusion in diabetic mice liver. Meanwhile, ACR could lead to exacerbation of diabetic symptoms in diabetic mice by disturbing the glucose and lipid metabolism in the liver, which mainly manifests as the accumulation of liver glycogen and liver lipids, the reduction of the activity/content of glycolytic and metabolizing enzyme as well as pentose phosphatase, upregulation of the gene expression in fatty acid transporter and gluconeogenesis, and downregulation of the gene expression in fatty acid synthesis and metabolism. Moreover, ACR exposure could induce oxidative stress, inflammation, and endoplasmic reticulum stress in the liver by a decrease in hepatic antioxidant enzyme activity and antioxidant content, an increase in inflammatory factor levels, and a change in the related protein expression of endoplasmic reticulum stress (ERS) and apoptosis-related pathways in diabetic mice. Statistical analysis results revealed that ACR-induced liver injury was highly correlated with inflammation and oxidative stress, and ERS and diabetic mice had a higher risk of liver injury than normal mice. Overall results suggested that female diabetic mice easily suffer from ACR-induced toxicity, and the reason was that ACR could induce further damage to the liver by worsening the condition of inflammation, oxidative stress, and ERS in the liver.


Assuntos
Acrilamida , Diabetes Mellitus Experimental , Estresse do Retículo Endoplasmático , Camundongos Endogâmicos BALB C , Animais , Feminino , Acrilamida/toxicidade , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Camundongos , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Estresse Oxidativo/efeitos dos fármacos
11.
Pediatr Blood Cancer ; 71(7): e30989, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38602300

RESUMO

BACKGROUND: Infantile hemangiomas (IHs) are common benign vascular tumors in infants. Apelin, an endogenous cytokine, is implicated in the angiogenesis of neoplastic diseases. We aimed to explore the association between apelin and IHs, providing a foundation for clinical applications. METHODS: We identified differential expression of apelin in proliferative IHs compared to healthy controls (HCs) through bioinformatics analysis of publicly available databases and verified by Immunofluorescence. Enzyme-linked immunosorbent assay was used to quantify the serum levels of apelin and vascular endothelial growth factor (VEGF) in a cohort of 116 cases of proliferative IHs, 65 cases of capillary malformations (CMs), and 70 HCs. RESULTS: Apelin and APJ (APLNR, apelin receptor) were identified as the significantly upregulated differentially expressed genes (DEGs) in proliferative IHs. Immunofluorescence staining indicated high expression of apelin in proliferative IHs, while minimal expression in non-IH lesions. Apelin in IHs was reduced following 6 months of propranolol treatment. Serum apelin levels were significantly higher in the IH group compared to both the CM and HC groups. Moreover, apelin exhibited excellent discriminatory ability in distinguishing IHs from HCs, with an area under the curve (AUC) exceeding 0.90. A positive correlation was observed between the levels of apelin and the size of superficial IHs. The expression profiles of VEGF and apelin in IHs were found to be consistent. CONCLUSIONS: Apelin shows promise as a potential biomarker for IHs. The association between apelin and IH size, as well as its responsiveness to propranolol treatment, indicates its possible utility as a valuable indicator for the therapeutic evaluation of IHs.


Assuntos
Apelina , Biomarcadores Tumorais , Humanos , Apelina/sangue , Lactente , Masculino , Feminino , Biomarcadores Tumorais/sangue , Hemangioma/sangue , Hemangioma/patologia , Receptores de Apelina/sangue , Receptores de Apelina/metabolismo , Fator A de Crescimento do Endotélio Vascular/sangue , Estudos de Casos e Controles , Propranolol/uso terapêutico , Prognóstico , Recém-Nascido
12.
Org Biomol Chem ; 22(17): 3459-3467, 2024 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-38597668

RESUMO

A water mediated three-component reaction of isatin, 4-aminocoumarin, and 1,3-cyclodicarbonyl compounds is reported for the synthesis of spiro[chromeno[4,3-b]cyclopenta[e]pyridine-7,3'-indoline]trione and the spiro[chromeno[4,3-b]quinoline 7,3'-indoline]trione. Up to 27 different spirooxindole derivatives were synthesized by this method. The bioactivity of these spirooxindole derivatives was evaluated and they were found to show antifungal activity against Cercospora arachidicola, Physalospora piricola, Rhizoctonia cerealis, and Fusarium moniliforme.


Assuntos
Antifúngicos , Benzopiranos , Indóis , Nitrilas , Compostos de Espiro , Água , Antifúngicos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Compostos de Espiro/farmacologia , Compostos de Espiro/química , Compostos de Espiro/síntese química , Água/química , Indóis/química , Indóis/farmacologia , Indóis/síntese química , Testes de Sensibilidade Microbiana , Oxindóis/farmacologia , Oxindóis/síntese química , Oxindóis/química , Estrutura Molecular , Relação Estrutura-Atividade , Fusarium/efeitos dos fármacos
13.
Cell ; 139(6): 1069-83, 2009 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-19962179

RESUMO

Chromosomal translocations are a hallmark of leukemia/lymphoma and also appear in solid tumors, but the underlying mechanism remains elusive. By establishing a cellular model that mimics the relative frequency of authentic translocation events without proliferation selection, we report mechanisms of nuclear receptor-dependent tumor translocations. Intronic binding of liganded androgen receptor (AR) first juxtaposes translocation loci by triggering intra- and interchromosomal interactions. AR then promotes site-specific DNA double-stranded breaks (DSBs) at translocation loci by recruiting two types of enzymatic activities induced by genotoxic stress and liganded AR, including activation-induced cytidine deaminase and the LINE-1 repeat-encoded ORF2 endonuclease. These enzymes synergistically generate site-selective DSBs at juxtaposed translocation loci that are ligated by nonhomologous end joining pathway for specific translocations. Our data suggest that the confluence of two parallel pathways initiated by liganded nuclear receptor and genotoxic stress underlies nonrandom tumor translocations, which may function in many types of tumors and pathological processes.


Assuntos
Neoplasias da Próstata/genética , Receptores Androgênicos/metabolismo , Transcrição Gênica , Translocação Genética , Linhagem Celular Tumoral , Dano ao DNA , Reparo do DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Íntrons , Elementos Nucleotídeos Longos e Dispersos , Masculino , Fases de Leitura Aberta , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulador Transcricional ERG
14.
Macromol Rapid Commun ; 45(3): e2300501, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37878266

RESUMO

Polythioureas (PTUs) show great potentials for applications in the new generation of film capacitors due to their excellent dielectric properties. Herein, the cis-trans copolymer chain of PTU is successfully tailored by employing cis and trans cyclohexyl spacers. The relationship between the copolymer chain conformation, microstructure, and dielectric properties is carefully explored by a series of analysis. Compared with cis conformation, the trans with less steric hindrance can promote the formation of H-bonds. The enhanced H-bonding interactions not only reduce the molecular inter-chain spacing, but also drive the self-assembly of molecular chains to form cylindrical and droplet nano-morphologies. The phase separation between cis and trans PTUs is confirmed by combining the experimental results of TEM and DSC, and the CT64-PTU with the most two-phase interface thus obtains the highest permittivity of 5.5 (@10 Hz). The reduced molecular inter-chain spacing is accompanied by a decreased hopping distance of charges, which improves breakdown strength by 17% from 498 MV/m to 580 MV/m. Therefore, the cis-trans copolymer chain conformation in PTU provides a simultaneous high permittivity and breakdown strength. This research offers a strategy to further design high-performance dielectrics via regulation of copolymer chain conformation.


Assuntos
Separação de Fases , Polímeros , Conformação Molecular
15.
Environ Res ; 246: 118010, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38157964

RESUMO

Environmental endocrine disrupting chemicals (EDCs), are a type of exogenous organic pollutants, are ubiquitous in natural aquatic environments. Currently, in addition to neurological, endocrine, developmental and reproductive toxicity, ecotoxicology studies on immunotoxicity are receiving increasing attention. In this review, the composition of immune system of zebrafish, the common indicators of immunotoxicity, the immunotoxicity of EDCs and their molecular mechanism were summarized. We reviewed the immunotoxicity of EDCs on zebrafish mainly in terms of immune organs, immunocytes, immune molecules and immune functions, meanwhile, the possible molecular mechanisms driving these effects were elucidated in terms of endocrine disruption, dysregulation of signaling pathways, and oxidative damage. Hopefully, this review will provide a reference for further investigation of the immunotoxicity of EDCs.


Assuntos
Disruptores Endócrinos , Animais , Disruptores Endócrinos/toxicidade , Peixe-Zebra , Sistema Imunitário , Reprodução , Ecotoxicologia
16.
Mol Ther ; 31(6): 1577-1595, 2023 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-37165619

RESUMO

Next-generation sequencing has revealed that less than 2% of transcribed genes are translated into proteins, with a large portion transcribed into noncoding RNAs (ncRNAs). Among these, long noncoding RNAs (lncRNAs) represent the largest group and are pervasively transcribed throughout the genome. Dysfunctions in lncRNAs have been found in various diseases, highlighting their potential as therapeutic, diagnostic, and prognostic targets. However, challenges, such as unknown molecular mechanisms and nonspecific immune responses, and issues of drug specificity and delivery present obstacles in translating lncRNAs into clinical applications. In this review, we summarize recent publications that have explored lncRNA functions in human diseases. We also discuss challenges and future directions for developing lncRNA treatments, aiming to bridge the gap between functional studies and clinical potential and inspire further exploration in the field.


Assuntos
RNA Longo não Codificante , Humanos , RNA Longo não Codificante/metabolismo , Engenharia Sanitária , RNA não Traduzido
17.
Mol Cell ; 64(5): 967-981, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27912097

RESUMO

Recent evidence suggests that lncRNAs play an integral regulatory role in numerous functions, including determination of cellular identity. We determined global expression (RNA-seq) and genome-wide profiles (ChIP-seq) of histone post-translational modifications and p53 binding in human embryonic stem cells (hESCs) undergoing differentiation to define a high-confidence set of 40 lncRNAs, which are p53 transcriptional targets. We focused on lncRNAs highly expressed in pluripotent hESCs and repressed by p53 during differentiation to identify lncPRESS1 as a p53-regulated transcript that maintains hESC pluripotency in concert with core pluripotency factors. RNA-seq of hESCs depleted of lncPRESS1 revealed that lncPRESS1 controls a gene network that promotes pluripotency. Further, we found that lncPRESS1 physically interacts with SIRT6 and prevents SIRT6 chromatin localization, which maintains high levels of histone H3K56 and H3K9 acetylation at promoters of pluripotency genes. In summary, we describe a p53-regulated, pluripotency-specific lncRNA that safeguards the hESC state by disrupting SIRT6 activity.


Assuntos
Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Células-Tronco Embrionárias/fisiologia , Histonas/metabolismo , Células-Tronco Pluripotentes/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Cromatina/metabolismo , Células-Tronco Embrionárias/citologia , Histona Desacetilases , Histonas/genética , Humanos , Células-Tronco Pluripotentes/citologia , Processamento de Proteína Pós-Traducional/genética , Sirtuínas/genética , Sirtuínas/metabolismo , Proteína Supressora de Tumor p53/genética
18.
Gen Comp Endocrinol ; 350: 114469, 2024 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-38360373

RESUMO

Tetrabromobisphenol A bis(2-hydroxyethyl) ether (TBBPA-DHEE) is the major TBBPA derivative. It has been detected in different environmental samples. Previous studies show that TBBPA-DHEE caused neurotoxicity in rats. In this study, juvenile zebrafish were exposed to various concentrations of TBBPA-DHEE to ascertain the potential neurotoxicity of TBBPA-DHEE, the chemical, and its possible molecular mechanism of action. Behavioral analysis revealed that TBBPA-DHEE could significantly increase the swimming distance and speed in the 1.5 mg/L group compared to the control. In contrast, the swimming distance and speed were significantly reduced in the 0.05 and 0.3 mg/L groups, affecting learning, memory, and neurodevelopment. Similarly, TBBPA-DHEE exposure caused a concentration-dependent significant increase in the levels of excitatory neurotransmitters, namely, dopamine, norepinephrine, and epinephrine, which could be attributed to the change observed in zebrafish behavior. This demonstrates the neurotoxicity of TBBPA-DHEE on juvenile zebrafish. The concentration-dependent increase in the IBR value revealed by the IBR index reveals the noticeable neurotoxic effect of TBBPA-DHEE. Transcriptomic analysis shows that TBBPA-DHEE exposure activated the PPAR signaling pathways, resulting in a disturbance of fatty acid (FA) metabolism and changes in the transcript levels of genes involved in these pathways, which could lead to lipotoxicity and hepatotoxicity. Our findings demonstrate a distinct endocrine-disrupting response to TBBPA-DHEE exposure, possibly contributing to abnormal behavioral alterations. This study provides novel insights into underlying the mechanisms and effects of TBBPA-DHEE on aquatic organisms, which may be helpful forenvironmental/human health risk assessments of the emerging pollutant.


Assuntos
Retardadores de Chama , Peixe-Zebra , Humanos , Ratos , Animais , Peixe-Zebra/metabolismo , Éteres/análise , Éteres/metabolismo , Análise de Sequência de RNA , Retardadores de Chama/toxicidade , Retardadores de Chama/análise , Retardadores de Chama/metabolismo
19.
BMC Pulm Med ; 24(1): 274, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38851701

RESUMO

BACKGROUND: Lung cancer (LC) commonly occurs in patients with combined pulmonary fibrosis and emphysema (CPFE) and chronic obstructive pulmonary disease (COPD), but comparative research is limited. This study examines clinical characteristics, treatments, and prognosis in LC patients with CPFE or COPD. METHODS: The retrospective study involved 75 lung cancer patients with CPFE and 182 with COPD. It analyzed clinical features, tumor pathology, pulmonary function, laboratory parameters, and treatment responses. RESULTS: Notable differences were found between the CPFE + LC and COPD + LC groups. Both groups were mostly elderly, male smokers. The CPFE + LC group had higher BMI and more adenocarcinoma and squamous cell carcinoma, while COPD + LC had predominantly squamous cell carcinoma. CPFE + LC tumors were mostly in the lower lobes; COPD + LC's were in the upper lobes. The CPFE + LC group showed higher tumor metastasis rates, more paraseptal emphysema, and elevated levels of TG, CEA, NSE, and Killer T Cells. In advanced stages (IIIB-IV), the CPFE + LC group receiving first-line treatment had shorter median progression-free survival (PFS) and a higher risk of progression or death than the COPD + LC group, regardless of whether it was non-small cell lung cancer (NSCLC) or small cell lung cancer (SCLC). No significant PFS difference was found within CPFE + LC between chemotherapy and immunotherapy, nor in immune-related adverse events between groups, with interstitial pneumonia being common. CONCLUSION: This study emphasizes distinct lung cancer characteristics in CPFE or COPD patients, highlighting the need for tailored diagnostic and treatment approaches. It advocates for further research to improve care for this high-risk group.


Assuntos
Neoplasias Pulmonares , Doença Pulmonar Obstrutiva Crônica , Humanos , Masculino , Estudos Retrospectivos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/mortalidade , Feminino , Idoso , Pessoa de Meia-Idade , Prognóstico , Fibrose Pulmonar , Enfisema Pulmonar , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Idoso de 80 Anos ou mais , Intervalo Livre de Progressão , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia
20.
BMC Health Serv Res ; 24(1): 548, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684977

RESUMO

BACKGROUND: The population aging trend and the shortage of elderly care workers require the long-term care profession to become more attractive. However, the professional attractiveness among long-term care workers has yet to be extensively studied. This study aims to identify the factors that influence the attractiveness of the long-term care profession for nursing home (NH) care workers.. METHODS: A cross-sectional study was conducted in more than 50 NHs. Perception of professional attractiveness among long-term care workers and potential associated factors were measured using the Attractive Work Questionnaire (AWQ) and structural instruments including the Fraboni Scale of Ageism (FSA) and the Maslach Burnout Inventory (MBI). A multiple linear regression method was employed to explore the influence of potential independent variables on professional attractiveness. RESULTS: The overall response rate was 99%. The results showed the score of professional attractiveness (185.37 ± 20.034), as well as the scores of each component (99.26 ± 11.258 for work condition, 30.13 ± 3.583 for work content, and 55.99 ± 7.074 for job satisfaction). Findings of multiple linear regression analysis indicated that age(ß = 0.129, p<.05), years of work(ß = 0.156, p<.05), 12-hour shifts(ß = 0.185, p<.05), and training times per year(ß = 0.148, p<.05) positively associated with long-term care workers perceived professional attractiveness. Whereas only ageism(ß=-0.267, p<.05) significantly and negatively influenced professional attractiveness. CONCLUSIONS: The perceived professional attractiveness of long-term care workers in NHs was acceptable. Age, years of work, shifts, training opportunities, and ageism contributed to the professional attractiveness of nursing home care workers in China. Target intervention measures should be taken to enhance the attractiveness of long-term care careers so as to avoid the shortage of long-term care workers.


Assuntos
Assistência de Longa Duração , Casas de Saúde , Humanos , Estudos Transversais , China , Masculino , Feminino , Assistência de Longa Duração/psicologia , Adulto , Inquéritos e Questionários , Pessoa de Meia-Idade , Satisfação no Emprego , Etarismo/psicologia , Esgotamento Profissional/psicologia
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