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1.
Sci Adv ; 9(44): eadk3860, 2023 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-37922355

RESUMO

Imaging and identifying target signatures and biomedical markers in the ultraviolet (UV) spectrum is broadly important to medical imaging, military target tracking, remote sensing, and industrial automation. However, current silicon-based imaging sensors are fundamentally limited because of the rapid absorption and attenuation of UV light, hindering their ability to resolve UV spectral signatures. Here, we present a bioinspired imaging sensor capable of wavelength-resolved imaging in the UV range. Inspired by the UV-sensitive visual system of the Papilio xuthus butterfly, the sensor monolithically combines vertically stacked photodiodes and perovskite nanocrystals. This imaging design combines two complementary UV detection mechanisms: The nanocrystal layer converts a portion of UV signals into visible fluorescence, detected by the photodiode array, while the remaining UV light is detected by the top photodiode. Our label-free UV fluorescence imaging data from aromatic amino acids and cancer/normal cells enables real-time differentiation of these biomedical materials with 99% confidence.


Assuntos
Borboletas , Luz , Animais , Raios Ultravioleta , Óxidos , Imagem Óptica
2.
Oncogene ; 42(50): 3684-3697, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37903896

RESUMO

Regulator of chromosome condensation domain-containing protein 1 (RCCD1), previously reported as a partner of histone H3K36 demethylase KDM8 involved in chromosome segregation, has been identified as a potential driver for breast cancer in a recent transcriptome-wide association study. We report here that, unexpectedly, RCCD1 is also localized in mitochondria. We show that RCCD1 resides in the mitochondrial matrix, where it interacts with the mitochondrial contact site/cristae organizing system (MICOS) and mitochondrial DNA (mtDNA) to regulate mtDNA transcription, oxidative phosphorylation, and the production of reactive oxygen species. Interestingly, RCCD1 is upregulated under hypoxic conditions, leading to decreased generation of reactive oxygen species and alleviated apoptosis favoring cancer cell survival. We show that RCCD1 promotes breast cancer cell proliferation in vitro and accelerates breast tumor growth in vivo. Indeed, RCCD1 is overexpressed in breast carcinomas, and its level of expression is associated with aggressive breast cancer phenotypes and poor patient survival. Our study reveals an additional dimension of RCCD1 functionality in regulating mitochondrial homeostasis, whose dysregulation inflicts pathologic states such as breast cancer.


Assuntos
Neoplasias da Mama , Mitocôndrias , Humanos , Feminino , Espécies Reativas de Oxigênio/metabolismo , Mitocôndrias/metabolismo , DNA Mitocondrial/genética , Neoplasias da Mama/patologia , Hipóxia/metabolismo , Carcinogênese/patologia , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Proteínas de Transporte/metabolismo , Proteínas de Membrana/genética , Histona Desmetilases/metabolismo
3.
Quant Imaging Med Surg ; 13(9): 6026-6036, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37711776

RESUMO

Background: Identifying cardioembolic stroke is important for the decision-making of endovascular treatment and anticoagulation therapy. We aimed to explore the features of cardioembolic stroke on 4-dimensional (4D) computed tomography angiography (4D-CTA) and assess whether these features can assist in classifying stroke etiology. Methods: In this retrospective study, we analyzed the images of 294 patients with acute ischemic stroke (AIS) from July 2020 to February 2022 at the First Affiliated Hospital of Chongqing Medical University, which had been consecutively collected. The data of 110 patients with occlusion of the M1/M2 segment of the middle cerebral artery (MCA) with/without intracranial internal carotid artery (ICA) occlusion were analyzed to calculate the clot burden score (CBS) and collateral score (CS), and the data of 88 patients with a clear origin and distal part were analyzed to measure clot length. Maximum intensity projection (MIP) and time MIP (tMIP) post-processing were used to assess the clot features. The Mann-Whitney U test was used to compare the clot characteristics between the 2 groups. Binary logistic regression was performed to assess the association between the image characteristics and cardioembolic stroke. Moreover, the receiver operating characteristic (ROC) curve was used to test the diagnostic efficacy of MIP/tMIP clot features in classifying cardioembolic stroke. Results: Age, high-risk factors for cerebrovascular disease, high/medium-risk sources of cardioembolic stroke, clot length, CBS, and CS were significantly different between the cardioembolic stroke group and non-cardioembolic stroke group (P<0.05). In the cardioembolic stroke group, the median MIP and tMIP clot length was 12 mm [interquartile range (IQR), 8.3-17.4 mm] and 9.3 mm (IQR, 6.8-14.3 mm), respectively. In the non-cardioembolic stroke group, the median MIP and tMIP clot length was 6.5 mm (IQR, 4.7-11.5 mm) and 5.8 mm (IQR, 3.9-10.6 mm), respectively. Binary logistic regression showed that cardioembolic stroke was significantly associated with MIP-clot length [odds ratio (OR), 1.15; 95% confidence interval (CI): 1.02-1.29; P<0.05], tMIP-clot length (OR, 1.18; 95% CI: 1.02-1.36; P<0.05), and tMIP-CBS (OR, 3.96; 95% CI: 1.08-14.58; P<0.05). The area under the ROC curve (AUC) values of MIP clot length for identifying cardioembolic stroke were 0.75 (95% CI: 0.65-0.84, P<0.05), with a cut-off value of >7.4 mm [sensitivity: 84.62% (95% CI: 69.50-94.10%); specificity: 59.18% (95% CI: 44.20-73.00%)]. The AUC value of tMIP clot length was 0.72 (95% CI: 0.61-0.81, P<0.05), with a cut-off value of >5.4 mm [sensitivity: 92.31% (95% CI: 79.10-98.40%); specificity: 48.98% (95% CI: 34.40-63.70%)]. Conclusions: Clot length and CBS were overestimated on MIP images. Among the clot characteristics, clot length could identify cardioembolic stroke.

4.
Nat Commun ; 14(1): 5076, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37604829

RESUMO

The chromatin-based rule governing the selection and activation of replication origins in metazoans remains to be investigated. Here we report that NFIB, a member of Nuclear Factor I (NFI) family that was initially purified in host cells to promote adenoviral DNA replication but has since mainly been investigated in transcription regulation, is physically associated with the pre-replication complex (pre-RC) in mammalian cells. Genomic analyses reveal that NFIB facilitates the assembly of the pre-RC by increasing chromatin accessibility. Nucleosome binding and single-molecule magnetic tweezers shows that NFIB binds to and opens up nucleosomes. Transmission electron microscopy indicates that NFIB promotes nucleosome eviction on parental chromatin. NFIB deficiency leads to alterations of chromosome contacts/compartments in both G1 and S phase and affects the firing of a subset of origins at early-replication domains. Significantly, cancer-associated NFIB overexpression provokes gene duplication and genomic alterations recapitulating the genetic aberrance in clinical breast cancer and empowering cancer cells to dynamically evolve growth advantage and drug resistance. Together, these results point a role for NFIB in facilitating replication licensing by acting as a genome organizer, shedding new lights on the biological function of NFIB and on the replication origin selection in eukaryotes.


Assuntos
Cromatina , Nucleossomos , Animais , Adenoviridae , Núcleo Celular , Cromatina/genética , Genômica , Mamíferos , Fatores de Transcrição NFI , Humanos
5.
Adv Exp Med Biol ; 1407: 1-27, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36920689

RESUMO

Pseudotyped viruses have been constructed for many viruses. They can mimic the authentic virus and have many advantages compared to authentic viruses. Thus, they have been widely used as a surrogate of authentic virus for viral function analysis, detection of neutralizing antibodies, screening viral entry inhibitors, and others. This chapter reviewed the progress in the field of pseudotyped viruses in general, including the definition and the advantages of pseudotyped viruses, their potential usage, different strategies or vectors used for the construction of pseudotyped viruses, and factors that affect the construction of pseudotyped viruses.


Assuntos
Proteínas do Envelope Viral , Pseudotipagem Viral , Proteínas do Envelope Viral/genética , Anticorpos Neutralizantes , Internalização do Vírus , Vetores Genéticos/genética
6.
Nat Commun ; 13(1): 7578, 2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36481721

RESUMO

How the carbohydrate binding protein galectin-3 might act as a diabetogenic and tumorogenic factor remains to be investigated. Here we report that intracellular galectin-3 interacts with Rag GTPases and Ragulator on lysosomes. We show that galectin-3 senses lipopolysaccharide (LPS) to facilitate the interaction of Rag GTPases and Ragulator, leading to the activation of mTORC1. We find that the lipopolysaccharide/galectin-3-Rag GTPases/Ragulator-mTORC1 axis regulates a cohort of genes including GLUT1, and HK2, and PKM2 that are critically involved in glucose uptake and glycolysis. Indeed, galectin-3 deficiency severely compromises LPS-promoted glycolysis. Importantly, the expression of HK2 is significantly reduced in diabetes patients. In multiple types of cancer including hepatocellular carcinoma (HCC), galectin-3 is highly expressed, and its level of expression is positively correlated with that of HK2 and PKM2 and negatively correlated with the prognosis of HCC patients. Our study unravels that galectin-3 is a sensor of LPS, an important modulator of the mTORC1 signaling, and a critical regulator of glucose metabolism.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Galectina 3/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Lipopolissacarídeos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética
7.
Signal Transduct Target Ther ; 7(1): 256, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35896529

RESUMO

A steep rise in Omicron reinfection cases suggests that this variant has increased immune evasion ability. To evaluate its antigenicity relationship with other variants, antisera from guinea pigs immunized with spike protein of SARS-CoV-2 variants of concern (VOCs) and variants of interest (VOIs) were cross-tested against pseudotyped variants. The neutralization activity against Omicron was markedly reduced when other VOCs or VOIs were used as immunogens, and Omicron (BA.1)-elicited sera did not efficiently neutralize the other variants. However, a Beta or Omicron booster, when administered as the 4th dose 3-months after the 3rd dose of any of the variants, could elicit broad neutralizing antibodies against all of the current variants including Omicron BA.1. Further analysis with 280 available antigen-antibody structures and quantification of immune escape from 715 reported neutralizing antibodies provide explanations for the observed differential immunogenicity. Three distinct clades predicted using an in silico algorithm for clustering of sarbecoviruses based on immune escape provide key information for rational design of vaccines.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anticorpos Antivirais/genética , COVID-19/genética , Análise por Conglomerados , Cobaias , Humanos , Glicoproteínas de Membrana , Testes de Neutralização , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Proteínas do Envelope Viral
8.
Front Immunol ; 13: 842607, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35603216

RESUMO

Background: A receptive endometrium is a prerequisite for successful embryo implantation. Mounting evidence shows that nearly one-third of infertility and implantation failures are caused by defective endometrial receptivity. This study pooled 218 subjects from multiple datasets to investigate the association of the immune infiltration level with reproductive outcome. Additionally, macrophage-endometrium interaction modules were constructed to explore an accurate and cost-effective approach to endometrial receptivity assessment. Methods: Immune-infiltration levels in 4 GEO datasets (n=218) were analyzed and validated through meta-analysis. Macrophage-endometrium interaction modules were selected based on the weighted gene co-expression network in GSE58144 and differentially expressed genes dominated by GSE19834 dataset. Xgboost, random forests, and regression algorithms were applied to predictive models. Subsequently, the efficacy of the models was compared and validated in the GSE165004 dataset. Forty clinical samples (RT-PCR and western blot) were performed for expression and model validation, and the results were compared to those of endometrial thickness in clinical pregnancy assessment. Results: Altered levels of Mϕs infiltration were shown to critically influence embryo implantation. The three selected modules, manifested as macrophage-endometrium interactions, were enrichment in the immunoreactivity, decidualization, and signaling functions and pathways. Moreover, hub genes within the modules exerted significant reproductive prognostic effects. The xgboost algorithm showed the best performance among the machine learning models, with AUCs of 0.998 (95% CI 0.994-1) and 0.993 (95% CI 0.979-1) in GSE58144 and GSE165004 datasets, respectively. These results were significantly superior to those of the other two models (random forest and regression). Similarly, the model was significantly superior to ultrasonography (endometrial thickness) with a better cost-benefit ratio in the population. Conclusion: Successful embryo implantation is associated with infiltration levels of Mϕs, manifested in genetic modules involved in macrophage-endometrium interactions. Therefore, utilizing the hub genes in these modules can provide a platform for establishing excellent machine learning models to predict reproductive outcomes in patients with defective endometrial receptivity.


Assuntos
Endométrio , Infertilidade , Implantação do Embrião/genética , Endométrio/metabolismo , Feminino , Humanos , Aprendizado de Máquina , Macrófagos , Gravidez
9.
Emerg Microbes Infect ; 11(1): 1024-1036, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35293847

RESUMO

SARS-CoV-2 has caused the COVID-19 pandemic. B.1.617 variants (including Kappa and Delta) have been transmitted rapidly in India. The transmissibility, pathogenicity, and neutralization characteristics of these variants have received considerable interest. In this study, 22 pseudotyped viruses were constructed for B.1.617 variants and their corresponding single amino acid mutations. B.1.617 variants did not exhibit significant enhanced infectivity in human cells, but mutations T478K and E484Q in the receptor binding domain led to enhanced infectivity in mouse ACE2-overexpressing cells. Furin activities were slightly increased against B.1.617 variants and cell-cell fusion after infection of B.1.617 variants were enhanced. Furthermore, B.1.617 variants escaped neutralization by several mAbs, mainly because of mutations L452R, T478K, and E484Q in the receptor binding domain. The neutralization activities of sera from convalescent patients, inactivated vaccine-immunized volunteers, adenovirus vaccine-immunized volunteers, and SARS-CoV-2 immunized animals against pseudotyped B.1.617 variants were reduced by approximately twofold, compared with the D614G variant.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anticorpos Neutralizantes , Fusão Celular , Humanos , Camundongos , Mutação , Pandemias , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus , Tropismo Viral
10.
Proc Natl Acad Sci U S A ; 119(6)2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35105803

RESUMO

BRD4 is well known for its role in super-enhancer organization and transcription activation of several prominent oncogenes including c-MYC and BCL2 As such, BRD4 inhibitors are being pursued as promising therapeutics for cancer treatment. However, drug resistance also occurs for BRD4-targeted therapies. Here, we report that BRD4 unexpectedly interacts with the LSD1/NuRD complex and colocalizes with this repressive complex on super-enhancers. Integrative genomic and epigenomic analyses indicate that the BRD4/LSD1/NuRD complex restricts the hyperactivation of a cluster of genes that are functionally linked to drug resistance. Intriguingly, treatment of breast cancer cells with a small-molecule inhibitor of BRD4, JQ1, results in no immediate activation of the drug-resistant genes, but long-time treatment or destabilization of LSD1 by PELI1 decommissions the BRD4/LSD1/NuRD complex, leading to resistance to JQ1 as well as to a broad spectrum of therapeutic compounds. Consistently, PELI1 is up-regulated in breast carcinomas, its level is negatively correlated with that of LSD1, and the expression level of the BRD4/LSD1/NuRD complex-restricted genes is strongly correlated with a worse overall survival of breast cancer patients. Together, our study uncovers a functional duality of BRD4 in super-enhancer organization of transcription activation and repression linking to oncogenesis and chemoresistance, respectively, supporting the pursuit of a combined targeting of BRD4 and PELI1 in effective treatment of breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Neoplasias/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Proteínas de Ciclo Celular/genética , Feminino , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Humanos , Células MCF-7 , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/genética , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Proteínas de Neoplasias/genética , Fatores de Transcrição/genética
11.
Emerg Microbes Infect ; 11(1): 18-29, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34818119

RESUMO

Severe acute respiratory syndrome coronavirus 2 variants have continued to emerge in diverse geographic locations with a temporal distribution. The Lambda variant containing multiple mutations in the spike protein, has thus far appeared mainly in South America. The variant harbours two mutations in the receptor binding domain, L452Q and F490S, which may change its infectivity and antigenicity to neutralizing antibodies. In this study, we constructed 10 pseudoviruses to study the Lambda variant and each individual amino acid mutation's effect on viral function, and used eight cell lines to study variant infectivity. In total, 12 monoclonal antibodies, 14 convalescent sera, and 23 immunized sera induced by mRNA vaccines, inactivated vaccine, and adenovirus type 5 vector vaccine were used to study the antigenicity of the Lambda variant. We found that compared with the D614G reference strain, Lambda demonstrated enhanced infectivity of Calu-3 and LLC-MK2 cells by 3.3-fold and 1.6-fold, respectively. Notably, the sensitivity of the Lambda variant to 5 of 12 neutralizing monoclonal antibodies, 9G11, AM180, R126, X593, and AbG3, was substantially diminished. Furthermore, convalescent- and vaccine-immunized sera showed on average 1.3-2.5-fold lower neutralizing titres against the Lambda variant. Single mutation analysis revealed that this reduction in neutralization was caused by L452Q and F490S mutations. Collectively, the reduced neutralization ability of the Lambda variant suggests that the efficacy of monoclonal antibodies and vaccines may be compromised during the current pandemic.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , COVID-19/virologia , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Anticorpos Monoclonais/química , Anticorpos Neutralizantes/química , Sítios de Ligação , COVID-19/prevenção & controle , Vacinas contra COVID-19/administração & dosagem , Linhagem Celular , Interações Hospedeiro-Patógeno , Humanos , Soros Imunes , Modelos Moleculares , Mutação , Testes de Neutralização , Ligação Proteica , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Relação Estrutura-Atividade , Pseudotipagem Viral
12.
Signal Transduct Target Ther ; 6(1): 346, 2021 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-34561414

RESUMO

Antibody-dependent cellular cytotoxicity (ADCC) responses to viral infection are a form of antibody regulated immune responses mediated through the Fc fragment. Whether severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) triggered ADCC responses contributes to COVID-19 disease development is currently not well understood. To understand the potential correlation between ADCC responses and COVID-19 disease development, we analyzed the ADCC activity and neutralizing antibody response in 255 individuals ranging from asymptomatic to fatal infections over 1 year post disease. ADCC was elicited by 10 days post-infection, peaked by 11-20 days, and remained detectable until 400 days post-infection. In general, patients with severe disease had higher ADCC activities. Notably, patients who had severe disease and recovered had higher ADCC activities than patients who had severe disease and deceased. Importantly, ADCC activities were mediated by a diversity of epitopes in SARS-COV-2-infected mice and induced to comparable levels against SARS-CoV-2 variants of concern (VOCs) (B.1.1.7, B.1.351, and P.1) as that against the D614G mutant in human patients and vaccinated mice. Our study indicates anti-SARS-CoV-2 ADCC as a major trait of COVID-19 patients with various conditions, which can be applied to estimate the extra-neutralization level against COVID-19, especially lethal COVID-19.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Citotoxicidade Celular Dependente de Anticorpos , COVID-19/imunologia , SARS-CoV-2/imunologia , Adulto , Idoso , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade
13.
EMBO J ; 40(19): e107974, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34459501

RESUMO

Identification of the driving force behind malignant transformation holds the promise to combat the relapse and therapeutic resistance of cancer. We report here that the single nucleotide polymorphism (SNP) rs4971059, one of 65 new breast cancer risk loci identified in a recent genome-wide association study (GWAS), functions as an active enhancer of TRIM46 expression. Recreating the G-to-A polymorphic switch caused by the SNP via CRISPR/Cas9-mediated homologous recombination leads to an overt upregulation of TRIM46. We find that TRIM46 is a ubiquitin ligase that targets histone deacetylase HDAC1 for ubiquitination and degradation and that the TRIM46-HDAC1 axis regulates a panel of genes, including ones critically involved in DNA replication and repair. Consequently, TRIM46 promotes breast cancer cell proliferation and chemoresistance in vitro and accelerates tumor growth in vivo. Moreover, TRIM46 is frequently overexpressed in breast carcinomas, and its expression is correlated with lower HDAC1 expression, higher histological grades, and worse prognosis of the patients. Together, our study links SNP rs4971059 to replication and to breast carcinogenesis and chemoresistance and support the pursuit of TRIM46 as a potential target for breast cancer intervention.


Assuntos
Alelos , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Histona Desacetilase 1/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Polimorfismo de Nucleotídeo Único , Linhagem Celular Tumoral , Proliferação de Células/genética , Reparo do DNA , Replicação do DNA , Elementos Facilitadores Genéticos , Feminino , Humanos , Íntrons , Proteínas do Tecido Nervoso/genética , Ligação Proteica , Proteólise , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
14.
EMBO Rep ; 22(7): e52036, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34114325

RESUMO

Dysregulation of lipid metabolism could lead to the development of metabolic disorders. We report here that the F-box protein JFK promotes excessive lipid accumulation in adipose tissue and contributes to the development of metabolic syndrome. JFK transgenic mice develop spontaneous obesity, accompanied by dyslipidemia, hyperglycemia, and insulin resistance, phenotypes that are further exacerbated under high-fat diets. In contrast, Jfk knockout mice are lean and resistant to diet-induced metabolic malfunctions. Liver-specific reconstitution of JFK expression in Jfk knockout mice leads to hepatic lipid accumulation resembling human hepatic steatosis and nonalcoholic fatty liver disease. We show that JFK interacts with and destabilizes ING5 through assembly of the SCF complex. Integrative transcriptomic and genomic analysis reveals that the SCFJFK -ING5 axis interferes with AMPK activity and fatty acid ß-oxidation, leading to the suppression of hepatic lipid catabolism. Significantly, JFK is upregulated and AMPKα1 is down-regulated in liver tissues from NAFLD patients. These results reveal that SCFJFK is a bona fide E3 ligase for ING5 and link the SCFJFK -ING5 axis to the development of obesity and metabolic syndrome.


Assuntos
Resistência à Insulina , Síndrome Metabólica , Hepatopatia Gordurosa não Alcoólica , Animais , Dieta Hiperlipídica/efeitos adversos , Humanos , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Síndrome Metabólica/genética , Síndrome Metabólica/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/genética , Obesidade/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo
15.
Mol Cell ; 81(14): 2960-2974.e7, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34111398

RESUMO

The transition of oxidized 5-methylcytosine (5mC) intermediates into the base excision repair (BER) pipeline to complete DNA demethylation remains enigmatic. We report here that UHRF2, the only paralog of UHRF1 in mammals that fails to rescue Uhrf1-/- phenotype, is physically and functionally associated with BER complex. We show that UHRF2 is allosterically activated by 5-hydroxymethylcytosine (5hmC) and acts as a ubiquitin E3 ligase to catalyze K33-linked polyubiquitination of XRCC1. This nonproteolytic action stimulates XRCC1's interaction with the ubiquitin binding domain-bearing RAD23B, leading to the incorporation of TDG into BER complex. Integrative epigenomic analysis in mouse embryonic stem cells reveals that Uhrf2-fostered TDG-RAD23B-BER complex is functionally linked to the completion of DNA demethylation at active promoters and that Uhrf2 ablation impedes DNA demethylation on latent enhancers that undergo poised-to-active transition during neuronal commitment. Together, these observations highlight an essentiality of 5hmC-switched UHRF2 E3 ligase activity in commissioning the accomplishment of active DNA demethylation.


Assuntos
5-Metilcitosina/análogos & derivados , Regulação Alostérica/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitinação/genética , Proteína 1 Complementadora Cruzada de Reparo de Raio-X/genética , 5-Metilcitosina/metabolismo , Animais , Linhagem Celular , Linhagem Celular Tumoral , Desmetilação do DNA , Metilação de DNA/genética , Reparo do DNA/genética , Enzimas Reparadoras do DNA/genética , Proteínas de Ligação a DNA/genética , Células HEK293 , Humanos , Células MCF-7 , Camundongos , Camundongos Knockout , Regiões Promotoras Genéticas/genética , Ligação Proteica/genética
16.
Nucleic Acids Res ; 49(8): 4421-4440, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33849069

RESUMO

Although overexpression of EZH2, a catalytic subunit of the polycomb repressive complex 2 (PRC2), is an eminent feature of various cancers, the regulation of its abundance and function remains insufficiently understood. We report here that the PRC2 complex is physically associated with ubiquitin-specific protease USP7 in cancer cells where USP7 acts to deubiquitinate and stabilize EZH2. Interestingly, we found that USP7-catalyzed H2BK120ub1 deubiquitination is a prerequisite for chromatin loading of PRC2 thus H3K27 trimethylation, and this process is not affected by H2AK119 ubiquitination catalyzed by PRC1. Genome-wide analysis of the transcriptional targets of the USP7/PRC2 complex identified a cohort of genes including FOXO1 that are involved in cell growth and proliferation. We demonstrated that the USP7/PRC2 complex drives cancer cell proliferation and tumorigenesis in vitro and in vivo. We showed that the expression of both USP7 and EZH2 elevates during tumor progression, corresponding to a diminished FOXO1 expression, and the level of the expression of USP7 and EZH2 strongly correlates with histological grades and prognosis of tumor patients. These results reveal a dual role for USP7 in the regulation of the abundance and function of EZH2, supporting the pursuit of USP7 as a therapeutic target for cancer intervention.


Assuntos
Carcinogênese , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Complexo Repressor Polycomb 2/metabolismo , Peptidase 7 Específica de Ubiquitina/metabolismo , Animais , Feminino , Proteína Forkhead Box O1/metabolismo , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Células Sf9 , Ubiquitinação , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Cell Rep ; 34(10): 108814, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33691114

RESUMO

Exploitation of naturally occurring genetic mutations could empower the discovery of novel aspects of established cancer genes. We report here that TRPS1, a gene linked to the tricho-rhino-phalangeal syndrome (TRPS) and recently identified as a potential breast cancer driver, promotes breast carcinogenesis through regulating replication. Epigenomic decomposition of TRPS1 landscape reveals nearly half of H3K9me3-marked heterochromatic origins are occupied by TRPS1, where it encourages the chromatin loading of APC/C, resulting in uncontrolled origin refiring. TRPS1 binds to the genome through its atypical H3K9me3 reading via GATA and IKAROS domains, while TRPS-related mutations affect its chromatin binding, replication boosting, and tumorigenicity. Concordantly, overexpression of wild-type but not TRPS-associated mutants of TRPS1 is sufficient to drive cancer genome amplifications, which experience an extrachromosomal route and dynamically evolve to confer therapeutic resistance. Together, these results uncover a critical function of TRPS1 in driving heterochromatin origin firing and breast cancer genome evolution.


Assuntos
Evolução Molecular , Heterocromatina/metabolismo , Proteínas Repressoras/metabolismo , Oxirredutases do Álcool/antagonistas & inibidores , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Replicação do DNA , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Histonas/metabolismo , Humanos , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Camundongos , Camundongos SCID , Mutagênese Sítio-Dirigida , Ligação Proteica , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/genética , Transplante Heterólogo
18.
Cell ; 184(9): 2362-2371.e9, 2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33735608

RESUMO

The 501Y.V2 variants of SARS-CoV-2 containing multiple mutations in spike are now dominant in South Africa and are rapidly spreading to other countries. Here, experiments with 18 pseudotyped viruses showed that the 501Y.V2 variants do not confer increased infectivity in multiple cell types except for murine ACE2-overexpressing cells, where a substantial increase in infectivity was observed. Notably, the susceptibility of the 501Y.V2 variants to 12 of 17 neutralizing monoclonal antibodies was substantially diminished, and the neutralization ability of the sera from convalescent patients and immunized mice was also reduced for these variants. The neutralization resistance was mainly caused by E484K and N501Y mutations in the receptor-binding domain of spike. The enhanced infectivity in murine ACE2-overexpressing cells suggests the possibility of spillover of the 501Y.V2 variants to mice. Moreover, the neutralization resistance we detected for the 501Y.V2 variants suggests the potential for compromised efficacy of monoclonal antibodies and vaccines.


Assuntos
COVID-19/imunologia , COVID-19/virologia , Evasão da Resposta Imune , SARS-CoV-2/patogenicidade , Enzima de Conversão de Angiotensina 2/metabolismo , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Antígenos Virais/imunologia , Linhagem Celular Tumoral , Células HEK293 , Humanos , Mutação/genética , SARS-CoV-2/genética
19.
Front Cell Infect Microbiol ; 11: 767578, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34976856

RESUMO

Human adenovirus infections can develop into diffuse multi-organ diseases in young children and immunocompromised patients, and severe cases can lead to death. However, there are no approved antiviral drugs available to treat adenovirus diseases. In this study, a chemiluminescence-based, high-throughput screening (HTS) assay was developed and applied to screen human adenovirus 5(HAdV5)inhibitors from 1,813 approved drug library and 556 traditional Chinese medicine-sourced small-molecule compounds. We identified three compounds with in vitro anti-HAdV5 activities in the low-micromolar range (EC50 values 0.3-4.5 µM, selectivity index values 20-300) that also showed inhibitory effects on HAdV3. Cardamomin (CDM) had good anti-HAdV5 activity in vitro. Furthermore, three dilutions of CDM (150, 75, and 37.5 mg/kg/d) administered to BALB/c mouse models inhibited HAdV5-fluc infection at 1 day post-infection by 80% (p < 0.05), 76% (p < 0.05), and 58% (p < 0.05), respectively. HE-staining of pathological tissue sections of mice infected with a wildtype adenoviral strain showed that CDM had a protective effect on tissues, especially in the liver, and greatly inhibited virus-induced necrosis of liver tissue. Thus, CDM inhibits adenovirus replication in vivo and in vitro. This study established a high-throughput screening method for anti-HAdV5 drugs and demonstrated CDM to be a candidate for HAdV5 therapy, potentially providing a new treatment for patients infected with adenoviruses.


Assuntos
Infecções por Adenovirus Humanos , Adenovírus Humanos , Adenoviridae/genética , Infecções por Adenovirus Humanos/tratamento farmacológico , Adenovírus Humanos/genética , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Pré-Escolar , Ensaios de Triagem em Larga Escala , Humanos , Camundongos , Replicação Viral
20.
Cancer Res ; 80(19): 4114-4128, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32651256

RESUMO

Copy number gain in chromosome 8q21 is frequently detected in breast cancer, yet the oncogenic potential underlying this amplicon in breast carcinogenesis remains to be delineated. We report here that ZNF704, a gene mapped to 8q21, is recurrently amplified in various malignancies including breast cancer. ZNF704 acted as a transcriptional repressor and interacted with the transcriptional corepressor SIN3A complex. Genome-wide interrogation of transcriptional targets revealed that the ZNF704/SIN3A complex represses a panel of genes including PER2 that are critically involved in the function of the circadian clock. Overexpression of ZNF704 prolonged the period and dampened the amplitude of the circadian clock. ZNF704 promoted the proliferation and invasion of breast cancer cells in vitro and accelerated the growth and metastasis of breast cancer in vivo. Consistently, the level of ZNF704 expression inversely correlated with that of PER2 in breast carcinomas, and high level of ZNF704 correlated with advanced histologic grades, lymph node positivity, and poor prognosis of patients with breast cancer, especially those with HER2+ and basal-like subtypes. These results indicate that ZNF704 is an important regulator of the circadian clock and a potential driver for breast carcinogenesis. SIGNIFICANCE: This study indicates that ZNF704 could be a potential oncogenic factor, disrupting circadian rhythm of breast cancer cells and contributing to breast carcinogenesis.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Ritmo Circadiano/genética , Fatores Genéricos de Transcrição/genética , Animais , Neoplasias da Mama/mortalidade , Linhagem Celular Tumoral , Proliferação de Células , Cromossomos Humanos Par 8 , Ritmo Circadiano/fisiologia , Feminino , Regulação Neoplásica da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Estimativa de Kaplan-Meier , Camundongos SCID , Proteínas Circadianas Period/genética , Prognóstico , Proteínas Repressoras/genética , Complexo Correpressor Histona Desacetilase e Sin3/genética , Fatores Genéricos de Transcrição/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
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