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1.
Mol Cell ; 70(5): 825-841.e6, 2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29861161

RESUMO

Super-enhancers are large clusters of enhancers that activate gene expression. Broad trimethyl histone H3 lysine 4 (H3K4me3) often defines active tumor suppressor genes. However, how these epigenomic signatures are regulated for tumor suppression is little understood. Here we show that brain-specific knockout of the H3K4 methyltransferase MLL4 (a COMPASS-like enzyme, also known as KMT2D) in mice spontaneously induces medulloblastoma. Mll4 loss upregulates oncogenic Ras and Notch pathways while downregulating neuronal gene expression programs. MLL4 enhances DNMT3A-catalyzed DNA methylation and SIRT1/BCL6-mediated H4K16 deacetylation, which antagonize expression of Ras activators and Notch pathway components, respectively. Notably, Mll4 loss downregulates tumor suppressor genes (e.g., Dnmt3a and Bcl6) by diminishing broad H3K4me3 and super-enhancers and also causes widespread impairment of these epigenomic signatures during medulloblastoma genesis. These findings suggest an anti-tumor role for super-enhancers and provide a unique tumor-suppressive mechanism in which MLL4 is necessary to maintain broad H3K4me3 and super-enhancers at tumor suppressor genes.


Assuntos
Neoplasias Cerebelares/genética , Metilação de DNA , Genes Supressores de Tumor , Histona-Lisina N-Metiltransferase/genética , Meduloblastoma/genética , Oncogenes , Processamento de Proteína Pós-Traducional , Acetilação , Animais , Proliferação de Células , Neoplasias Cerebelares/metabolismo , Neoplasias Cerebelares/patologia , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA Metiltransferase 3A , Regulação Neoplásica da Expressão Gênica , Genes ras , Histona-Lisina N-Metiltransferase/deficiência , Lisina , Meduloblastoma/metabolismo , Meduloblastoma/patologia , Camundongos Knockout , Proteínas Proto-Oncogênicas c-bcl-6/genética , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo , Transdução de Sinais , Sirtuína 1/genética , Sirtuína 1/metabolismo
2.
Cell Mol Life Sci ; 81(1): 76, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38315203

RESUMO

Metastatic cancer is a major cause of cancer-related mortality; however, the complex regulation process remains to be further elucidated. A large amount of preliminary investigations focus on the role of epigenetic mechanisms in cancer metastasis. Notably, the posttranslational modifications were found to be critically involved in malignancy, thus attracting considerable attention. Beyond acetylation, novel forms of acylation have been recently identified following advances in mass spectrometry, proteomics technologies, and bioinformatics, such as propionylation, butyrylation, malonylation, succinylation, crotonylation, 2-hydroxyisobutyrylation, lactylation, among others. These novel acylations play pivotal roles in regulating different aspects of energy mechanism and mediating signal transduction by covalently modifying histone or nonhistone proteins. Furthermore, these acylations and their modifying enzymes show promise regarding the diagnosis and treatment of tumors, especially tumor metastasis. Here, we comprehensively review the identification and characterization of 11 novel acylations, and the corresponding modifying enzymes, highlighting their significance for tumor metastasis. We also focus on their potential application as clinical therapeutic targets and diagnostic predictors, discussing the current obstacles and future research prospects.


Assuntos
Histonas , Neoplasias , Humanos , Acilação , Histonas/metabolismo , Acetilação , Processamento de Proteína Pós-Traducional , Neoplasias/genética
3.
Nucleic Acids Res ; 51(21): 11534-11548, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37831104

RESUMO

RNA expression of a gene is determined by not only transcriptional regulation, but also post-transcriptional regulation of RNA decay. The precise regulation of RNA stability in the cell plays an important role in normal development. Dysregulation of RNA stability can lead to diseases such as cancer. Here we found tumor suppressor RNAs tended to decay fast in normal cell types when compared with other RNAs. Consistent with a negative effect of m6A modification on RNA stability, we observed preferential deposition of m6A on tumor suppressor RNAs. Moreover, abundant m6A and fast decay of tumor suppressor RNAs both tended to be further enhanced in prostate cancer cells relative to normal prostate epithelial cells. Further, knockdown of m6A methyltransferase METTL3 and reader YTHDF2 in prostate cancer cells both posed stronger effect on tumor suppressor RNAs than on other RNAs. These results indicated a strong post transcriptional expression regulatability mediated by abundant m6A modification on tumor suppressor RNAs.


Assuntos
Genes Supressores de Tumor , Neoplasias da Próstata , Estabilidade de RNA , RNA Mensageiro , Humanos , Masculino , Metiltransferases/genética , Neoplasias da Próstata/química , Neoplasias da Próstata/genética , RNA/genética , RNA Mensageiro/química
4.
Nucleic Acids Res ; 51(10): 5271-5284, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37094074

RESUMO

Liquid-liquid phase separation (LLPS) plays a critical role in regulating gene transcription via the formation of transcriptional condensates. However, LLPS has not been reported to be engineered as a tool to activate endogenous gene expression in mammalian cells or in vivo. Here, we developed a droplet-forming CRISPR (clustered regularly interspaced short palindromic repeats) gene activation system (DropCRISPRa) to activate transcription with high efficiency via combining the CRISPR-SunTag system with FETIDR-AD fusion proteins, which contain an N-terminal intrinsically disordered region (IDR) of a FET protein (FUS or TAF15) and a transcription activation domain (AD, VP64/P65/VPR). In this system, the FETIDR-AD fusion protein formed phase separation condensates at the target sites, which could recruit endogenous BRD4 and RNA polymerase II with an S2 phosphorylated C-terminal domain (CTD) to enhance transcription elongation. IDR-FUS9Y>S and IDR-FUSG156E, two mutants with deficient and aberrant phase separation respectively, confirmed that appropriate phase separation was required for efficient gene activation. Further, the DropCRISPRa system was compatible with a broad set of CRISPR-associated (Cas) proteins and ADs, including dLbCas12a, dAsCas12a, dSpCas9 and the miniature dUnCas12f1, and VP64, P65 and VPR. Finally, the DropCRISPRa system could activate target genes in mice. Therefore, this study provides a robust tool to activate gene expression for foundational research and potential therapeutics.


Assuntos
Sistemas CRISPR-Cas , Ativação Transcricional , Animais , Camundongos , Sistemas CRISPR-Cas/genética , Mamíferos , Proteínas Nucleares/genética , Fatores de Transcrição/genética
5.
Nucleic Acids Res ; 51(12): 6020-6038, 2023 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-37125636

RESUMO

Cell identity genes are distinct from other genes with respect to the epigenetic mechanisms to activate their transcription, e.g. by super-enhancers and broad H3K4me3 domains. However, it remains unclear whether their post-transcriptional regulation is also unique. We performed a systematic analysis of transcriptome-wide RNA stability in nine cell types and found that unstable transcripts were enriched in cell identity-related pathways while stable transcripts were enriched in housekeeping pathways. Joint analyses of RNA stability and chromatin state revealed significant enrichment of super-enhancers and broad H3K4me3 domains at the gene loci of unstable transcripts. Intriguingly, the RNA m6A methyltransferase, METTL3, preferentially binds to chromatin at super-enhancers, broad H3K4me3 domains and their associated genes. METTL3 binding intensity is positively correlated with RNA m6A methylation and negatively correlated with RNA stability of cell identity genes, probably due to co-transcriptional m6A modifications promoting RNA decay. Nanopore direct RNA-sequencing showed that METTL3 knockdown has a stronger effect on RNA m6A and mRNA stability for cell identity genes. Our data suggest a run-and-brake model, where cell identity genes undergo both frequent transcription and fast RNA decay to achieve precise regulation of RNA expression.


Assuntos
Cromatina , Regulação da Expressão Gênica , Estabilidade de RNA , Cromatina/genética , Epigênese Genética , Metiltransferases/metabolismo , RNA/química
6.
J Am Chem Soc ; 146(1): 824-832, 2024 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-38123470

RESUMO

Glucose and its polyhydroxy saccharide analogs are complex molecules that serve as essential structural components in biomacromolecules, natural products, medicines, and agrochemicals. Within the expansive realm of saccharides, a significant area of research revolves around chemically transforming naturally abundant saccharide units to intricate or uncommon molecules such as oligosaccharides or rare sugars. However, partly due to the presence of multiple hydroxyl groups with similar reactivities and the structural complexities arising from stereochemistry, the transformation of unprotected sugars to the desired target molecules remains challenging. One such formidable challenge lies in the efficient and selective activation and modification of the C-O bonds in saccharides. In this study, we disclose a modular 2-fold "tagging-editing" strategy that allows for direct and selective editing of C-O bonds of saccharides, enabling rapid preparation of valuable molecules such as rare sugars and drug derivatives. The first step, referred to as "tagging", involves catalytic site-selective installation of a photoredox active carboxylic ester group to a specific hydroxyl unit of an unprotected sugar. The second step, namely, "editing", features a C-O bond cleavage to form a carbon radical intermediate that undergoes further transformations such as C-H and C-C bond formations. Our strategy constitutes the most effective and shortest route in direct transformation and modification of medicines and other molecules bearing unprotected sugars.


Assuntos
Carboidratos , Açúcares , Glucose , Oligossacarídeos , Radical Hidroxila
7.
Eur J Immunol ; 53(4): e2250100, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36648433

RESUMO

Autoimmune hepatitis (AIH) eventually progresses to liver fibrosis, cirrhosis, and even hepatocellular carcinoma, causing irreversible damage to the liver. Concanavalin A-induced hepatitis in mice is a well-established model with pathophysiology similar to that of immune-mediated liver injury in human viral and autoimmune hepatitis, and it has been widely used to explore the pathogenesis and clinical treatment of human immune hepatitis. Artemisinin has been shown to exhibit anti-inflammatory effects through unclear mechanisms. In this study, we aimed to assess the effect of the artemisinin derivative TPN10466 on AIH. In vitro studies showed that TPN10466 dose dependently inhibited the percentage of IFN-γ-producing T cells. Further studies showed that TPN10466 attenuated the disease severity of AIH by downregulating the ability of lymphocytes to secrete IFN-γ and by reducing lymphocyte number in the liver. In addition, we found that TPN10466 treatment reduced T-cell responses by inhibiting JNK, ERK, and p38 pathways. In conclusion, our work suggests that TPN10466 provides protection against the autoimmune disease AIH by suppressing the inflammatory response of T cells, suggesting that TPN10466 may be a promising potential agent for the treatment of AIH.


Assuntos
Artemisininas , Hepatite Autoimune , Animais , Humanos , Camundongos , Artemisininas/metabolismo , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Concanavalina A/metabolismo , Concanavalina A/farmacologia , Concanavalina A/uso terapêutico , Hepatite Autoimune/tratamento farmacológico , Fígado/patologia , Sistema de Sinalização das MAP Quinases
8.
Small ; : e2405476, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39148187

RESUMO

The advancement of acceptors plays a pivotal role in determining photovoltaic performance. While previous efforts have focused on optimizing acceptor-donor-acceptor1-donor-acceptor (A-DA1-D-A)-typed acceptors by adjusting side chains, end groups, and conjugated extension of the electron-deficient central A1 unit, the systematic exploration of the impact of peripheral aryl substitutions, particularly with different electron groups, on the A1 unit and its influence on device performance is still lacking. In this study, three novel acceptors - QxTh, QxPh, and QxPy - with distinct substitutions on the quinoxaline (Qx) are designed and synthesized. Density functional theory (DFT) analyses reveal that QxPh, featuring a phenyl-substituted Qx, exhibits the smallest molecular binding energies and a tightest π···π stacking distance. Consequently, the PM6:QxPh device demonstrates a better power conversion efficiency (PCE) of 17.1% compared to the blends incorporating QxTh (16.4%) and QxPy (15.7%). This enhancement is primarily attributed to suppressed charge recombination, improved charge extraction, and more favorable molecular stacking and morphology. Importantly, introducing QxPh as a guest acceptor into the PM6:BTP-eC9 binary system yields an outstanding PCE of 19.5%, indicating the substantial potential of QxPh in advancing ternary device performance. The work provides deep insights into the expansion of high-performance organic photovoltaic materials through peripheral aryl substitution strategy.

9.
Eur J Nucl Med Mol Imaging ; 51(6): 1753-1762, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38212531

RESUMO

PURPOSE: This is a first-in-human study to evaluate the radiation dosimetry of a new prostate-specific membrane antigen (PSMA)-targeted radiopharmaceutical, [18F]AlF-P16-093, and also initial investigation of its ability to detect PSMA-positive tumors using PET scans in a cohort of prostate cancer (PCa) patients. METHODS: The [18F]AlF-P16-093 was automatically synthesized with a GE TRACERlab. A total of 23 patients with histopathologically proven PCa were prospectively enrolled. Dosimetry and biodistribution study investigations were carried out on a subset of six (6) PCa patients, involving multiple time-point scanning. The mean absorbed doses were estimated with PMOD and OLINDA software. RESULTS: [18F]AlF-P16-093 was successfully synthesized, and radiochemical purity was > 95%, and average labeling yield was 36.5 ± 8.3% (decay correction, n = 12). The highest tracer uptake was observed in the kidneys, spleen, and liver, contributing to an effective dose of 16.8 ± 1.3 µSv/MBq, which was ~ 30% lower than that of [68Ga]Ga-P16-093. All subjects tolerated the PET examination well, and no reportable side-effects were observed. The PSMA-positive tumors displayed rapid uptake, and they were all detectable within 10 min, and no additional lesions were observed in the following multi-time points scanning. Each patient had at least one detectable tumor lesion, and a total of 356 tumor lesions were observed, including intraprostatic, lymph node metastases, bone metastases, and other soft tissue metastases. CONCLUSIONS: We report herein a streamlined method for high yield synthesis of [18F]AlF-P16-093. Preliminary study in PCa patients has demonstrated its safety and acceptable radiation dosimetry. The initial diagnostic study indicated that [18F]AlF-P16-093 PET/CT is efficacious and potentially useful for a widespread application in the diagnosis of PCa patients.


Assuntos
Antígenos de Superfície , Glutamato Carboxipeptidase II , Neoplasias da Próstata , Radiometria , Humanos , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Idoso , Glutamato Carboxipeptidase II/metabolismo , Pessoa de Meia-Idade , Antígenos de Superfície/metabolismo , Distribuição Tecidual , Compostos Radiofarmacêuticos/farmacocinética , Compostos Radiofarmacêuticos/química , Radioisótopos de Flúor/química , Idoso de 80 Anos ou mais , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada
10.
Eur J Nucl Med Mol Imaging ; 51(7): 2124-2133, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38285206

RESUMO

PURPOSE: This paper discusses the optimization of pharmacokinetic modelling and alternate simplified quantification method for [18F]AlF-P16-093, a novel tracer for in vivo imaging of prostate cancer. METHODS: Dynamic PET/CT scans were conducted on eight primary prostate cancer patients, followed by a whole-body scan at 60 min post-injection. Time-activity curves (TACs) were obtained by drawing volumes of interest for primary prostatic and metastatic lesions. Optimal kinetic modelling involved evaluating three compartmental models (1T2K, 2T3K, and 2T4K) accounting for fractional blood volume (Vb). The simplified quantification method was then determined based on the correlation between the static uptake measure and total distribution volume (Vt) obtained from the optimal pharmacokinetic analysis. RESULTS: In total, 17 intraprostatic lesions, 10 lymph nodes, and 36 osseous metastases were evaluated. Visually, the contrast of the tumor increased and showed the steepest incline within the first few minutes, whereas background activity decreased over time. Full pharmacokinetic analysis revealed that a reversible two-compartmental (2T4K) model is the preferred kinetic model for the given tracer. The kinetic parameters K1, k3, Vb, and Vt were all significantly higher in lesions when compared with normal tissue (P < 0.01). Several simplified protocols were tested for approximating comprehensive dynamic quantification in tumors, with image-based SURmean (the ratio of tumor SUVmean to blood SUVmean) within the 28-34 min window found to be sufficient for approximating the total distribution Vt values (R2 = 0.949, P < 0.01). Both Vt and SURmean correlated significantly with the total serum prostate-specific antigen (tPSA) levels (P < 0.01). CONCLUSIONS: This study introduced an optimized pharmacokinetic modelling approach and a simplified acquisition method for [18F]AlF-P16-093, a novel PSMA-targeted radioligand, highlighting the feasibility of utilizing one static PET imaging (between 30 and 60 min) for the diagnosis of prostate cancer. Note that the image-derived input function in this study may not reflect the true corrected plasma input function, therefore the interpretation of the associated kinetic parameter estimates should be done with caution.


Assuntos
Modelos Biológicos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/metabolismo , Idoso , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos/farmacocinética , Cinética , Lisina/análogos & derivados , Ureia/análogos & derivados
11.
FASEB J ; 37(5): e22901, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37002884

RESUMO

Alveolar echinococcosis (AE) is a lethal helminthic liver disease caused by persistent infection with Echinococcus multilocularis (E. multilocularis). Although more and more attention has been paid to the macrophages in E. multilocularis infection, the mechanism of macrophage polarization, a critical player in liver immunity, is seldom studied. NOTCH signaling is involved in cell survival and macrophage-mediated inflammation, but the role of NOTCH signaling in AE has been equally elusive. In this study, liver tissue samples from AE patients were collected and an E. multilocularis infected mouse model with or without blocking NOTCH signaling was established to analyze the NOTCH signaling, fibrotic and inflammatory response of the liver after E. multilocularis infection. Changes in polarization and origin of hepatic macrophages were analyzed by flow cytometry. In vitro qRT-PCR and Western blot assays were performed to analyze key receptors and ligands in NOTCH signaling. Our data demonstrated that hepatic fibrosis develops after AE, and the overall blockade of NOTCH signaling caused by DAPT treatment exacerbates the levels of hepatic fibrosis and alters the polarization and origin of hepatic macrophages. Blocking NOTCH signaling in macrophages after E. multilocularis infection downregulates M1 and upregulates M2 expression. The downregulation of NTCH3 and DLL-3 in the NOTCH signaling pathway is significant. Therefore, NOTCH3/DLL3 may be the key pathway in NOTCH signaling regulating macrophage polarization affecting fibrosis caused by AE.


Assuntos
Equinococose , Inibidores da Agregação Plaquetária , Camundongos , Animais , Inibidores da Agregação Plaquetária/farmacologia , Equinococose/complicações , Cirrose Hepática/induzido quimicamente , Transdução de Sinais , Fibrose
12.
Eur Radiol ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834788

RESUMO

OBJECTIVES: To investigate the potential utility of [18F]fibroblast activation protein inhibitor (FAPI) positron emission tomography/computed tomography (PET/CT) for evaluating pulmonary artery (PA) masses, and compare it with [18F]fluorodeoxyglucose (FDG) PET/CT. METHODS: Participants with clinically suspected PA malignancy were prospectively enrolled and underwent dual-tracer PET/CT ([18F]FAPI-42 and [18F]FDG) imaging. Visual analysis and semi-quantitative parameters were compared between the two types of radiotracers. The tissue specimen underwent immunohistochemical staining to verify FAP expression in the tissue. RESULTS: Thirty-three patients (18 males/15 females; mean age 53.1 ± 15.4 years) were enrolled. All 21 patients with malignant PA masses were FDG-positive (100%), whereas 20 out of 21 patients were FAPI-positive (95.2%). All 12 patients with benign PA masses were both negative in FDG and FAPI PET. The mean maximum standardized uptake value (SUVmax) and target-to-background ratio (TBR) of FAPI and FDG in malignant PA masses were significantly higher than those of benign masses. Although there was no significant difference in SUVmax between FDG and FAPI in malignant PA masses (11.36 vs. 9.18, p = 0.175), the TBR (liver) and TBR (left ventricle) were more favorable for FAPI than for FDG (13.04 vs. 5.17, p < 0.001); (median: 7.75 vs. 2.75, p = 0.007). Immunohistochemical analysis (n = 16) validated that the level of FAP expression corresponded strongly to the uptake of FAPI in PET/CT scans (rs = 0.712, p = 0.002). For clinical management, FAPI PET found more metastatic lesions than FDG PET in 4 patients, with 2 patients upgrading and 1 patient changing treatment decisions. CONCLUSIONS: FAPI PET/CT is feasible in the diagnosis of PA masses. Although not superior to FDG PET/CT, FAPI PET/CT showed better target-to-background contrast. CLINICAL RELEVANCE STATEMENT: This study found that FAPI PET/CT is not superior to FDG PET/CT in diagnosing PA masses, but FAPI PET/CT displays better target-to-background contrast and more positive lesions, which may help improve disease management. KEY POINTS: Pulmonary malignancies lack specificity in clinical manifestations, laboratory tests, and routine imaging examinations. FAPI PET/CT is not diagnostically better than FDG PET/CT but displays better target-to-background contrast and more positive lesions. Dual-tracer PET/CT ([18F]FAPI-42 and [18F]FDG) imaging improves clinical management of pulmonary artery masses.

13.
J Immunol ; 208(7): 1545-1553, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35277421

RESUMO

Multiple sclerosis (MS) is a chronic inflammatory demyelinating autoimmune disease with chronic inflammatory demyelination of the CNS. Experimental autoimmune encephalomyelitis (EAE) is an important animal model to study MS, with many pathological phenomena similar to MS. Th17 cells are important regulators of EAE and MS pathogenesis. Most cytokines needed for Th cell development are secreted by APCs, such as dendritic cells (DCs). Consequently, MS could be improved by inhibiting cytokine secretion from DCs. In this study, we reported that chlorzoxazone could ameliorate EAE pathogenesis via inhibiting IL-6 production by DCs. The EAE signs in the chlorzoxazone-treated group of mice were relieved, which was mainly manifested as lower clinical scores, a decrease in the number of immune cells, and a reduction of demyelination in the CNS. Moreover, the proportion of Th17 cells in the spleen and CNS decreased significantly. In vitro experiments showed that chlorzoxazone treatment significantly reduced DC-derived IL-6 production. In the DC-T cell coculture experiment, significantly decreased Th17 differentiation was observed after chlorzoxazone treatment. In addition, mass spectrometric analysis was performed to elucidate the mechanism by which chlorzoxazone affected EAE and DC function. We showed that the effect of chlorzoxazone on inhibiting the secretion of IL-6 by DCs may be mediated via the AMP-activated protein kinase pathway. Overall, our study elucidated the key role of chlorzoxazone in regulating EAE pathogenesis and suggested that it might be used as a new drug for MS patients.


Assuntos
Encefalomielite Autoimune Experimental , Animais , Clorzoxazona/metabolismo , Clorzoxazona/farmacologia , Células Dendríticas , Humanos , Interleucina-6/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células Th17
14.
Mol Cell ; 63(3): 470-84, 2016 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-27477906

RESUMO

Histone acetylation, including acetylated H3K14 (H3K14ac), is generally linked to gene activation. Monomethylated histone H3 lysine 4 (H3K4me1), together with other gene-activating marks, denotes active genes. In contrast to usual gene-activating functions of H3K14ac and H3K4me1, we here show that the dual histone modification mark H3K4me1-H3K14ac is recognized by ZMYND8 (also called RACK7) and can function to counteract gene expression. We identified ZMYND8 as a transcriptional corepressor of the H3K4 demethylase JARID1D. ZMYND8 antagonized the expression of metastasis-linked genes, and its knockdown increased the cellular invasiveness in vitro and in vivo. The plant homeodomain (PHD) and Bromodomain cassette in ZMYND8 mediated the combinatorial recognition of H3K4me1-H3K14ac and H3K4me0-H3K14ac by ZMYND8. These findings uncover an unexpected role for the signature H3K4me1-H3K14ac in attenuating gene expression and reveal a metastasis-suppressive epigenetic mechanism in which ZMYND8's PHD-Bromo cassette couples H3K4me1-H3K14ac with downregulation of metastasis-linked genes.


Assuntos
Movimento Celular , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias da Próstata/metabolismo , Receptores de Superfície Celular/metabolismo , Acetilação , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Histonas/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundário , Masculino , Camundongos Nus , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/metabolismo , Modelos Moleculares , Invasividade Neoplásica , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Ligação Proteica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Interferência de RNA , Receptores de Quinase C Ativada , Receptores de Superfície Celular/genética , Fatores de Tempo , Transcrição Gênica , Transfecção , Carga Tumoral , Proteínas Supressoras de Tumor
15.
BMC Anesthesiol ; 24(1): 4, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166663

RESUMO

BACKGROUND: To evaluate the effect of esketamine combined with ropivacaine hydrochloride on the occurrence of postpartum depression (PPD) after labor analgesia under epidural analgesia pump and explore the possible mechanisms. METHODS: A total of 120 women aged 24 to 36 years old who underwent labor analgesia by epidural analgesia pump, with American Society of Anesthesiologists (ASA) physical status II were enrolled. According to the formula of epidural analgesia pump, all participants were randomly divided into two groups: esketamine group (Group E) and control group (Group C). Epidural anaesthesia were operated in all women between L2 and L3 after cervical dilation up to 2 ~ 3 cm. After successful puncture, the epidural catheter was placed 3.5 cm toward the head and 1% lidocaine was injected for 3 ml. The epidural analgesia pump was connected. Esketamine (0.2 mg/kg) combined with 0.75% ropivacaine hydrochloride (20 ml) were diluted by normal saline up to 100 ml in Group E, when only the equal dose of ropivacaine hydrochloride was used in Group C. The visual analogue scale (VAS) before analgesia (T1), 5 (T2), 10 (T3) and 20 (T4) minutes after analgesia were measured. The duration of the first and second stage of labor, the Apgar score of fetus at delivery, postpartum hemorrhage, consumption of esketamine and ropivacaine were recorded. The incidence of PPD was recorded at 1 week and 6 weeks after delivering. The occurrence of side effects such as nausea and vomiting, dizziness, and nightmares were also recorded for 48 h after delivering. The levels of leptin, norepinephrine(NE), and epinephrine(E) in the peripheral venous blood were measured before labor analgesia and at 24 h, 1 week, and 6 weeks after delivering. RESULTS: Compared with Group C, the VAS score at T2, T3 and T4 were significantly lower in Group E (P < 0.01). Compared with Group C, the incidence of PPD was significantly lower at 1 week and 6 weeks after delivering in Group E (P < 0.01). Compared with Group C, the levels of leptin were significantly higher at 24 h and 1 week after delivering in Group E (P < 0.01), while NE and E (P < 0.01) were lower at the same time (P < 0.01). There were no significant difference of the duration of the first and second stage of labor, the Apgar score of fetus at delivery, postpartum hemorrhage, consumption of ropivacaine and the side effects for 48 h after delivering between the two groups. CONCLUSION: Esketamine combined with ropivacaine hydrochloride used in labor analgesia can significantly reduce the incidence of postpartum depression after delivering without increasing related side effects, which may be related to the regulation of leptin, norepinephrine, and epinephrine in the serum. TRIAL REGISTRATION: The trial was registered at the Chinese Clinical Trial Registry on 30/05/2022 (CTRI registration number-ChiCTR2200060387). URL of registry: https://www.chictr.org.cn/bin/home .


Assuntos
Analgesia Epidural , Analgesia Obstétrica , Depressão Pós-Parto , Hemorragia Pós-Parto , Gravidez , Feminino , Humanos , Adulto Jovem , Adulto , Ropivacaina , Leptina , Hemorragia Pós-Parto/tratamento farmacológico , Depressão Pós-Parto/tratamento farmacológico , Analgésicos/uso terapêutico , Epinefrina , Norepinefrina , Anestésicos Locais/uso terapêutico
16.
Angew Chem Int Ed Engl ; : e202407890, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958602

RESUMO

Developing novel n-type organic semiconductors is an enduring research endeavour, given their pivotal roles in organic electronics and their relative scarcity compared to p-type counterparts. In this study, a new strategy was employed to synthesize n-type organic semiconductors featuring fully-fused conjugated backbone. By attaching two sets of adjacent amino and formyl groups to the indacenodithiophene-based central cores and triggering a tandem reaction of Knoevenagel condensation-intramolecular cyclization, DFA1 and DFA2 were realized. The solution-processed organic field effect transistors based on DFA1 exhibited unipolar n-type transport character with a decent electron mobility of ca. 0.10 cm2 V-1 s-1 (ca. 0.038 cm2 V-1 s-1 for DFA2 based devices). When employing DFA1 as a third component in organic solar cells, a high power conversion efficiency of 19.2% can be achieved in ternary devices fabricated with PM6:L8-BO:DFA1. This work paves a new pathway in the molecular engineering of n-type organic semiconductors, propelling relevant research forward.

17.
Opt Express ; 31(3): 3708-3718, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36785357

RESUMO

Polarization fading degrades the performance of phase-sensitive optical time-domain reflectometry (φ-OTDR) seriously and has to be suppressed. A novel scheme is proposed in this paper to combat polarization fading, which features a quite simple transceiver structure by exploiting both polarization diversity through delayed polarization multiplexing and the aperiodic autocorrelation of pseudorandom binary sequence. The components of Jones matrix of a sensing fiber are then shown at those four peaks of aperiodic autocorrelation and can be obtained directly without complicated computation to give a polarization independent phase variation due to vibration. Moreover, the scheme does not require stringent match between the delayed time and the spacing between sensors. The proposed scheme is demonstrated through experiment on a weak fiber Bragg grating (WFBG) array, which shows a high crosstalk rejection ratio among sensors of more than 50 dB and a high dynamic range of more than 30 dB.

18.
Chemistry ; 29(31): e202203661, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-36918349

RESUMO

1,2,4-Triazolium salts are precursors of N-heterocyclic carbenes (NHCs), which have been extensively used as effective catalysts and ligands for both asymmetric and non-enantioselective reactions. Nevertheless, they are also a kind of quaternary ammonium compounds (QACs) that possess amphipathic properties. The unique chemical and physical properties of 1,2,4-triazolium salts have received significant attention from scientists focusing on the development of novel bioactive molecules as pesticides and medicines. It is timely and meaningful to summarize the bioactivities of 1,2,4-triazolium salt derivatives against various bacteria, fungi, cancer cells, and other pathogens in the past 30 years. Meanwhile, the structure-activity relationship (SAR) of 1,2,4-triazolium salts was also summarized. Finally, our perspective on the future development and applications of triazolium salts as agrichemicals or human drugs is presented.

19.
FASEB J ; 36(12): e22625, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36331546

RESUMO

Renal fibrosis, a common pathological manifestation of virtually all types of chronic kidney disease (CKD), ultimately predisposes patients to end-stage renal disease. However, there is no effective therapy for renal fibrosis. Our earlier studies proved that RIP3-mediated necroptosis might be an important mode of renal tubular cell death in rats with chronic renal injury. Under transmission electron microscopy (TEM), we found morphological changes in the necrosis of human renal tissue, and the percentage of necrotic cells increased significantly in patients with stages 2 and 3a CKD. Immunofluorescence analyses showed that the percentages of TUNEL+ /RIP3+ double-positive and TUNEL+ /MLKL+ double-positive tubular epithelial cells in renal tubules of patients with stages 2 and 3a CKD were significantly increased compared to those in control patients without renal disease. Immunohistochemistry analyses of renal biopsy specimens from patients with CKD revealed RIP3, MLKL, and p-MLKL upregulation in patients with stages 2 and 3a CKD, suggesting that necroptosis of renal tubular epithelial cells in CKD patients occurs, and the peak of necroptosis was in stages 2 and 3a CKD. We showed that profibrotic factor proteins (TGF-ß1, Smad2 and Smad3) and fibroblast activation markers (α-SMA and Vimentin) were specifically upregulated in stage 2 and 3a CKD patients. In addition, Pearson correlation analysis showed that the percentage of necroptotic renal tubular epithelial cells was positively correlated with TGF-ß1 and collagen-I. We also showed that RIP1/3 or MLKL inhibitors decreased the expression of RIP3, MLKL, TGF-ß1, and Smad3 in HK-2 cells treated with TNF-α. FGF-2, α-SMA, Vimentin and FN were overexpressed in the hRIFs cultured with the supernatant of necroptotic HK-2 cells, whereas necroptosis blockers (Nec-1s, GSK'872 and NSA) and TGF-ß1/Smad3 pathway antagonists (LY364947 and SIS3) reduced FGF-2, α-SMA, Vimentin and FN levels. Collectively, necroptosis of renal tubular epithelial cells in CKD patients occurs, and the peak of necroptosis was in stages 2 and 3a CKD. Renal tubular epithelial cell necroptosis mediates renal tubulointerstitial fibrosis in patients with chronic kidney disease, which is related to the TGF-ß1/Smad3 signaling pathway.


Assuntos
Insuficiência Renal Crônica , Fator de Crescimento Transformador beta1 , Humanos , Ratos , Animais , Fator de Crescimento Transformador beta1/metabolismo , Necroptose , Vimentina/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fibrose , Células Epiteliais/metabolismo , Insuficiência Renal Crônica/metabolismo , Rim/metabolismo , Necrose/patologia
20.
Muscle Nerve ; 67(6): 481-488, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36945795

RESUMO

INTRODUCTION/AIMS: Descriptions of the clinical characteristics of anti-AChR-MuSK-LRP4 antibody-negative myasthenia gravis (triple-negative myasthenia gravis, TNMG) are lacking in the current literature. Therefore, we investigated the clinical characteristics of TNMG in Chinese patients. METHODS: We retrospectively analyzed 925 patients with MG registered in the Department of Neuroimmunology, Henan Institute of Medical and Pharmaceutical Sciences from January 2015 to March 2021. RESULTS: One hundred six patients diagnosed with TNMG were included in the study. The average age of onset was 32.4 y, with a male-to-female ratio of 1:1. The age of onset showed a bimodal distribution: 0-9 y and 40-49 y. Adult patients were more likely to have weakness of limb and bulbar muscles (p < .05). Thymic hyperplasia was found in 20.2% of the patients. Younger patients were more likely to relapse. The rate of adult early-onset myasthenia gravis reaching complete stable remission and pharmacological remission was 47.6%, and the prognosis was better than that in juvenile-onset myasthenia gravis (p = .019). Older age of onset was the only risk factor for the development of generalized TNMG from ocular TNMG (R = 1.046, p = .002, 95% confidence interval 1.017-1.077). DISCUSSION: This study showed that the clinical characteristics of patients with TNMG varied among the different age groups. Significant findings included a bimodal distribution of onset age, coexisting thymic hyperplasia, and a generally favorable prognosis.


Assuntos
Miastenia Gravis , Hiperplasia do Timo , Adulto , Humanos , Masculino , Feminino , Receptores Colinérgicos , Estudos Retrospectivos , Receptores Proteína Tirosina Quinases , Autoanticorpos , Recidiva Local de Neoplasia , Miastenia Gravis/diagnóstico , Miastenia Gravis/epidemiologia , China/epidemiologia , Proteínas Relacionadas a Receptor de LDL
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