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1.
Mol Cell ; 84(20): 3899-3915.e7, 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39368466

RESUMO

Histone H3.3 is frequently mutated in tumors, with the lysine 36 to methionine mutation (K36M) being a hallmark of chondroblastomas. While it is known that H3.3K36M changes the epigenetic landscape, its effects on gene expression dynamics remain unclear. Here, we use a synthetic reporter to measure the effects of H3.3K36M on silencing and epigenetic memory after recruitment of the ZNF10 Krüppel-associated box (KRAB) domain, part of the largest class of human repressors and associated with H3K9me3 deposition. We find that H3.3K36M, which decreases H3K36 methylation and increases histone acetylation, leads to a decrease in epigenetic memory and promoter methylation weeks after KRAB release. We propose a model for establishment and maintenance of epigenetic memory, where the H3K36 methylation pathway is necessary to maintain histone deacetylation and convert H3K9me3 domains into DNA methylation for stable epigenetic memory. Our quantitative model can inform oncogenic mechanisms and guide development of epigenetic editing tools.


Assuntos
Metilação de DNA , Epigênese Genética , Histonas , Mutação , Histonas/metabolismo , Histonas/genética , Humanos , Acetilação , Regiões Promotoras Genéticas , Proteínas Repressoras/metabolismo , Proteínas Repressoras/genética , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Lisina/metabolismo , Memória Epigenética
2.
Genome Res ; 33(3): 412-426, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36958795

RESUMO

Tn5 transposon tagments double-stranded DNA and RNA/DNA hybrids to generate nucleic acids that are ready to be amplified for high-throughput sequencing. The nucleic acid substrates for the Tn5 transposon must be explored to increase the applications of Tn5. Here, we found that the Tn5 transposon can transpose oligos into the 5' end of single-stranded DNA longer than 140 nucleotides. Based on this property of Tn5, we developed a tagmentation-based and ligation-enabled single-stranded DNA sequencing method called TABLE-seq. Through a series of reaction temperature, time, and enzyme concentration tests, we applied TABLE-seq to strand-specific RNA sequencing, starting with as little as 30 pg of total RNA. Moreover, compared with traditional dUTP-based strand-specific RNA sequencing, this method detects more genes, has a higher strand specificity, and shows more evenly distributed reads across genes. Together, our results provide insights into the properties of Tn5 transposons and expand the applications of Tn5 in cutting-edge sequencing techniques.


Assuntos
DNA de Cadeia Simples , DNA , DNA de Cadeia Simples/genética , Sequência de Bases , RNA/genética , Análise de Sequência de RNA , Elementos de DNA Transponíveis/genética
3.
Brief Bioinform ; 25(5)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39073831

RESUMO

Histone modifications, known as histone marks, are pivotal in regulating gene expression within cells. The vast array of potential combinations of histone marks presents a considerable challenge in decoding the regulatory mechanisms solely through biological experimental approaches. To overcome this challenge, we have developed a method called CatLearning. It utilizes a modified convolutional neural network architecture with a specialized adaptation Residual Network to quantitatively interpret histone marks and predict gene expression. This architecture integrates long-range histone information up to 500Kb and learns chromatin interaction features without 3D information. By using only one histone mark, CatLearning achieves a high level of accuracy. Furthermore, CatLearning predicts gene expression by simulating changes in histone modifications at enhancers and throughout the genome. These findings help comprehend the architecture of histone marks and develop diagnostic and therapeutic targets for diseases with epigenetic changes.


Assuntos
Código das Histonas , Histonas , Humanos , Histonas/metabolismo , Histonas/genética , Cromatina/metabolismo , Cromatina/genética , Epigênese Genética , Redes Neurais de Computação , Biologia Computacional/métodos , Regulação da Expressão Gênica
4.
Nucleic Acids Res ; 52(10): 5549-5571, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38499486

RESUMO

Complex organisms generate differential gene expression through the same set of DNA sequences in distinct cells. The communication between chromatin and RNA regulates cellular behavior in tissues. However, little is known about how chromatin, especially histone modifications, regulates RNA polyadenylation. In this study, we found that FUS was recruited to chromatin by H3K36me3 at gene bodies. The H3K36me3 recognition of FUS was mediated by the proline residues in the ZNF domain. After these proline residues were mutated or H3K36me3 was abolished, FUS dissociated from chromatin and bound more to RNA, resulting in an increase in polyadenylation sites far from stop codons genome-wide. A proline mutation corresponding to a mutation in amyotrophic lateral sclerosis contributed to the hyperactivation of mitochondria and hyperdifferentiation in mouse embryonic stem cells. These findings reveal that FUS is an H3K36me3 reader protein that links chromatin-mediated alternative polyadenylation to human disease.


Assuntos
Histonas , Poliadenilação , Proteína FUS de Ligação a RNA , Animais , Humanos , Camundongos , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Diferenciação Celular/genética , Cromatina/metabolismo , Cromatina/genética , Células HEK293 , Histonas/metabolismo , Histonas/genética , Mitocôndrias/metabolismo , Mitocôndrias/genética , Células-Tronco Embrionárias Murinas , Mutação , Poliadenilação/genética , Proteína FUS de Ligação a RNA/genética , Proteína FUS de Ligação a RNA/metabolismo , Linhagem Celular , Domínios Proteicos
5.
Hepatology ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557414

RESUMO

BACKGROUND AND AIMS: Epigenetic reprogramming and escape from terminal differentiation are poorly understood enabling characteristics of liver cancer. Keratin 19 (KRT19), classically known to form the intermediate filament cytoskeleton, is a marker of stemness and worse prognosis in liver cancer. This study aimed to address the functional roles of KRT19 in liver tumorigenesis and to elucidate the underlying mechanisms. APPROACH AND RESULTS: Using multiplexed genome editing of hepatocytes in vivo, we demonstrated that KRT19 promoted liver tumorigenesis in mice. Cell fractionation revealed a previously unrecognized nuclear fraction of KRT19. Tandem affinity purification identified histone deacetylase 1 and REST corepressor 1, components of the corepressor of RE-1 silencing transcription factor (CoREST) complex as KRT19-interacting proteins. KRT19 knockout markedly enhanced histone acetylation levels. Mechanistically, KRT19 promotes CoREST complex formation by enhancing histone deacetylase 1 and REST corepressor 1 interaction, thus increasing the deacetylase activity. ChIP-seq revealed hepatocyte-specific genes, such as hepatocyte nuclear factor 4 alpha ( HNF4A ), as direct targets of KRT19-CoREST. In addition, we identified forkhead box P4 as a direct activator of aberrant KRT19 expression in liver cancer. Furthermore, treatment of primary liver tumors and patient-derived xenografts in mice suggest that KRT19 expression has the potential to predict response to histone deacetylase 1 inhibitors especially in combination with lenvatinib. CONCLUSIONS: Our data show that nuclear KRT19 acts as a transcriptional corepressor through promoting the deacetylase activity of the CoREST complex, resulting in dedifferentiation of liver cancer. These findings reveal a previously unrecognized function of KRT19 in directly shaping the epigenetic landscape in cancer.

6.
Mol Cancer ; 23(1): 152, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39085861

RESUMO

Chemotherapy in combination with immunotherapy has gradually shown substantial promise to increase T cell infiltration and antitumor efficacy. However, paclitaxel in combination with immune checkpoint inhibitor targeting PD-1/PD-L1 was only used to treat a small proportion of metastatic triple-negative breast cancer (TNBC), and the clinical outcomes was very limited. In addition, this regimen cannot prevent paclitaxel-induced peripheral neuropathy. Therefore, there was an urgent need for a novel target to enhance the antitumor activity of paclitaxel and alleviate chemotherapy-induced peripheral neuropathy in breast cancer. Here, we found that Dickkopf-1 (DKK1) expression was upregulated in multiply subtypes of human breast cancer specimens after paclitaxel-based chemotherapy. Mechanistic studies revealed that paclitaxel promoted DKK1 expression by inducing EGFR signaling in breast cancer cells, and the upregulation of DKK1 could hinder the therapeutic efficacy of paclitaxel by suppressing the infiltration and activity of CD8+ T cells in tumor microenvironment. Moreover, paclitaxel treatment in tumor-bearing mice also increased DKK1 expression through the activation of EGFR signaling in the primary sensory dorsal root ganglion (DRG) neurons, leading to the development of peripheral neuropathy, which is charactered by myelin damage in the sciatic nerve, neuropathic pain, and loss of cutaneous innervation in hindpaw skin. The addition of an anti-DKK1 antibody not only improved therapeutic efficacy of paclitaxel in two murine subtype models of breast cancer but also alleviated paclitaxel-induced peripheral neuropathy. Taken together, our findings providing a potential chemoimmunotherapy strategy with low neurotoxicity that can benefit multiple subtypes of breast cancer patients.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular , Paclitaxel , Doenças do Sistema Nervoso Periférico , Paclitaxel/efeitos adversos , Paclitaxel/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Humanos , Animais , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Feminino , Camundongos , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo
7.
Br J Cancer ; 131(8): 1387-1398, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39266624

RESUMO

BACKGROUND: Temozolomide (TMZ) is the first-line chemotherapeutic drug for gliomas treatment. However, the clinical efficacy of TMZ in glioma patients was very limited. Therefore, it is urgently needed to discover a novel approach to increase the sensitivity of glioma cells to TMZ. METHODS: Western blot, immunohistochemical staining, and qRT-PCR assays were used to explore the mechanisms underlying TMZ promoting DKK1 expression and andrographolide (AND) inhibiting DKK1 expression. HPLC was used to detect the ability of andrographolide (AND) to penetrate the blood-brain barrier. MTT assay, bioluminescence images, magnetic resonance imaging (MRI) and H&E staining were employed to measure the proliferative activity of glioma cells and the growth of intracranial tumors. RESULTS: TMZ can promote DKK1 expression in glioma cells and brain tumors of an orthotopic model of glioma. DKK1 could promote glioma cell proliferation and tumor growth in an orthotopic model of glioma. Mechanistically, TMZ increased EGFR expression and subsequently induced the activation of its downstream MEK-ERK and PI3K-Akt pathways, thereby promoting DKK1 expression in glioma cells. Andrographolide inhibited TMZ-induced DKK1 expression through inactivating MEK-ERK and PI3K-Akt pathways. Andrographolide can cross the blood-brain barrier, the combination of TMZ and andrographolide not only improved the anti-tumor effects of TMZ but also showed a survival benefit in an orthotopic model of glioma. CONCLUSION: Andrographolide can enhance anti-tumor activity of TMZ against glioma by inhibiting DKK1 expression.


Assuntos
Antineoplásicos Alquilantes , Neoplasias Encefálicas , Proliferação de Células , Diterpenos , Glioma , Peptídeos e Proteínas de Sinalização Intercelular , Temozolomida , Diterpenos/farmacologia , Diterpenos/uso terapêutico , Temozolomida/farmacologia , Glioma/tratamento farmacológico , Glioma/patologia , Glioma/genética , Glioma/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Humanos , Animais , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Camundongos , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Camundongos Nus , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Sinergismo Farmacológico , Receptores ErbB/genética , Receptores ErbB/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos
8.
Small ; 20(16): e2306010, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37884476

RESUMO

Realizing ideal charge transport in field-effect transistors (FETs) of conjugated polymers is crucial for evaluating device performance, such as carrier mobility and practical applications of conjugated polymers. However, the current FETs using conjugated polymers as the active layers generally show certain non-ideal transport characteristics and poor stability. Here, ideal charge transport of n-type polymer FETs is achieved on flexible polyimide substrates by using an organic-inorganic hybrid double-layer dielectric. Deposited conjugated polymer films show highly ordered structures and low disorder, which are supported by grazing-incidence wide-angle X-ray scattering, near-edge X-ray absorption fine structure, and molecular dynamics simulations. Furthermore, the organic-inorganic hybrid double-layer dielectric provides low interfacial defects, leading to excellent charge transport in FETs with high electron mobility (1.49 ± 0.46 cm2 V-1 s-1) and ideal reliability factors (102 ± 7%). Fabricated polymer FETs show a self-encapsulation effect, resulting in high stability of the FET charge transport. The polymer FETs still work with high mobility above 1 cm2 V-1 s-1 after storage in air for more than 300 days. Compared with state-of-the-art conjugated polymer FETs, this work simultaneously achieves ideal charge transport and environmental stability in n-type polymer FETs, facilitating rapid device optimization of high-performance polymer electronics.

9.
Chemistry ; 30(16): e202304372, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38191767

RESUMO

Incorporating heteroatoms can effectively modulate the molecular optoelectronic properties. However, the fundamental understanding of BN doping effects in BN-embedded polycyclic aromatic hydrocarbons (PAHs) is underexplored, lacking rational guidelines to modulate the electronic structures through BN units for advanced materials. Herein, a concise synthesis of novel B2N2-perylenes with BN doped at the bay area is achieved to systematically explore the doping effect of BN position on the photophysical properties of PAHs. The shift of BN position in B2N2-perylenes alters the π electron conjugation, aromaticity and molecular rigidness significantly, achieving substantially higher electron transition abilities than those with BN doped in the nodal plane. It is further clarified that BN position dominates the photophysical properties over BN orientation. The revealed guideline here may apply generally to novel BN-PAHs, and aid the advancement of BN-PAHs with highly-emissive performance.

10.
FASEB J ; 37(11): e23250, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37819682

RESUMO

Vision loss and blindness are frequently caused by photoreceptor degeneration, for example in age-related macular degeneration and retinitis pigmentosa. However, there is no effective medicine to treat these photoreceptor degeneration-related diseases. Cell senescence is a common phenotype in many diseases; however, few studies have reported whether it occurs in photoreceptor degeneration diseases. Herein, we identified that cell senescence is associated with photoreceptor degeneration induced by N-methyl-N-nitrosourea (MNU, a commonly used photoreceptor degeneration model), presented as increased senescence-associated ß-galactosidase activity, DNA damage, oxidative stress and inflammation-related cytokine Interleukin 6 (IL6), and upregulation of cyclin p21 or p16. These results suggested that visual function might be protected using anti-aging treatment. Furthermore, Hyperoside is reported to help prevent aging in various organs. In this study, we showed that Hyperoside, delivered intravitreally, alleviated photoreceptor cell senescence and ameliorated the functional and morphological degeneration of the retina in vivo and in vitro. Importantly, Hyperoside attenuated the MNU-induced injury and aging of photoreceptors via AMPK-ULK1 signaling inhibition. Taken together, our results demonstrated that Hyperoside can prevent MNU-induced photoreceptor degeneration by inhibiting cell senescence via the AMPK-ULK1 pathway.


Assuntos
Proteínas Quinases Ativadas por AMP , Degeneração Retiniana , Animais , Proteínas Quinases Ativadas por AMP/metabolismo , Apoptose , Senescência Celular , Modelos Animais de Doenças , Metilnitrosoureia/toxicidade , Células Fotorreceptoras de Vertebrados/metabolismo , Retina/metabolismo , Degeneração Retiniana/induzido quimicamente , Degeneração Retiniana/tratamento farmacológico , Degeneração Retiniana/prevenção & controle
11.
Inorg Chem ; 63(18): 8171-8179, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38655575

RESUMO

Although 1,10-phenanthroline has been proven to hold a strong complexing capacity for f-block elements and their derivatives have been applied in many fields, research on more highly or completely rigid phenanthroline ligands is still rare due to the challenging syntheses. Here, we reported three tetradentate ligands 2,9-di(pyridin-2-yl)-1,10-phenanthroline (L1), 12-(pyridin-2-yl)-5,6-dihydroquinolino[8,7b][1,10]phenanthroline (L2), and 5,6,11,12-tetrahydrobenzo[2,1-b:3,4-b']bis([1,10]phenanthroline) (L3) with increasing preorganization on the side chain; among which, L3 is fully preorganized. Their complexation reactions with Eu(III) were systematically investigated by electrospray ionization mass spectrometry (ESI-MS), UV-vis titrations, and single-crystal structures. It is found that all three ligands form only 1:1 M/L complexes with Eu(III). The single-crystal structures revealed that the three ligands hold similar coordination modes, while their stability constants determined by UV-vis titrations were L3 (4.80 ± 0.01) > L2 (4.38 ± 0.01) > L1 (3.88 ± 0.01). This trend is supported not only by the thermodynamic stability of rigid ligands compared to free ligands but also by the conclusion that rigid ligands exhibit faster reaction rates (lower energy barrier) than free ligands kinetically. This work is helpful in providing theoretical guidance for the subsequent development of highly preorganized chelating ligands with strong coordination ability and high selectivity for f-block elements.

12.
Graefes Arch Clin Exp Ophthalmol ; 262(4): 1121-1129, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37999773

RESUMO

PURPOSE: To explore the role of choroidopathy in diabetic retinopathy (DR) by investigating the correlation between alterations of choroidal vessel and photoreceptors during the early stage of DR. METHODS: We performed a cross-sectional comparison of diabetic patients without DR (NDR group; n=16) and those with mild nonproliferative diabetic retinopathy (NPDR group; n=39). Optical coherence tomography (OCT) images of choroidal vessel alterations and photoreceptor structures were evaluated using the choroidal vascularity index (CVI) and adjusted ellipsoid zone (EZ) reflectivity, respectively. To evaluate the function of cone photoreceptors, the fundamental, harmonic amplitudes, the parameters S and Rmp3 were calculated from the electroretinogram (ERG). These factors were compared between groups. The correlation between the CVI and parameters describing the function and structure of the photoreceptors was evaluated. RESULTS: The significant decrease was observed in the CVI in the NPDR group compared to the NDR group (0.67 ± 0.04 vs. 0.70 ± 0.06; p = 0.028), but not in the adjusted EZ reflectivity or ERG parameters. In NPDR group and merging the 2 groups, CVI was moderately positively correlated with the fundamental amplitude obtained by the flicker ERG (NPDR only: r = 0.506; p = 0.001; merge the 2 groups: r = 0.423; p = 0.001), which was regulated by the response of the cone photoreceptors. The CVI was positively and moderately correlated with the logS (NPDR only: r = 0.462; p = 0.003; merge the 2 groups: r = 0.355; p = 0.008), indicating the sensitivity of cone cell light transduction. CONCLUSION: Compared to eyes without DR, CVI decreased representing choroidal vascular changes in eyes with mild NPDR. These changes may be related to the functional impairment of cone photoreceptors, especially phototransduction sensitivity, as the DR develops.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Humanos , Retinopatia Diabética/diagnóstico , Estudos Transversais , Células Fotorreceptoras Retinianas Cones/fisiologia , Eletrorretinografia/métodos , Tomografia de Coerência Óptica/métodos
13.
Zygote ; 32(2): 119-129, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38248909

RESUMO

Zygotic genome activation (ZGA) is a critical event in early embryonic development, and thousands of genes are involved in this delicate and sophisticated biological process. To date, however, only a handful of these genes have revealed their core functions in this special process, and therefore the roles of other genes still remain unclear. In the present study, we used previously published transcriptome profiling to identify potential key genes (candidate genes) in minor ZGA and major ZGA in both human and mouse specimens, and further identified the conserved genes across species. Our results showed that 887 and 760 genes, respectively, were thought to be specific to human and mouse in major ZGA, and the other 135 genes were considered to be orthologous genes. Moreover, the conserved genes were most enriched in rRNA processing in the nucleus and cytosol, ribonucleoprotein complex biogenesis, ribonucleoprotein complex assembly and ribosome large subunit biogenesis. The findings of this first comprehensive identification and characterization of candidate genes in minor and major ZGA provide relevant insights for future studies on ZGA.


Assuntos
Genoma , Zigoto , Animais , Zigoto/metabolismo , Camundongos , Humanos , Genoma/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Transcriptoma/genética , Feminino , Desenvolvimento Embrionário/genética , Mamíferos/genética
14.
Int J Phytoremediation ; 26(12): 2010-2020, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38932483

RESUMO

Urease-producing bacteria (UPB) are widely present in soil and play an important role in soil ecosystems. In this study, 65 UPB strains were isolated from cadmium (Cd)-polluted soil around a lead-zinc mine in Yunnan Province, China. The Cd tolerance, removal of Cd from aqueous solution, production of indoleacetic acid (IAA) and plant growth-promoting effects of these materials were investigated. The results indicate that among the 65 UPB strains, four strains with IAA-producing ability were screened and identified as Bacillus thuringiensis W6-11, B. cereus C7-4, Serratia marcescens W11-10, and S. marcescens C5-6. Among the four strains, B. cereus C7-4 had the highest Cd tolerance, median effect concentration (EC50) of 59.94 mg/L. Under Cd 5 mg/L, S. marcescens C5-6 had the highest Cd removal from aqueous solution, up to 69.83%. Under Cd 25 mg/kg, inoculation with B. cereus C7-4 significantly promoted maize growth in a sand pot by increasing the root volume, root surface area, and number of root branches by 22%, 29%, and 20%, respectively, and plant height and biomass by 16% and 36%, respectively, and significantly increasing Cd uptake in the maize roots. Therefore, UPB is a potential resource for enhancing plant adaptability to Cd stress in plants with Cd-polluted habitats.


This study utilized urease-producing bacteria screened from the soil of lead zinc mining areas in Yunnan, China as the research object, enriching the microbial resources in Yunnan. In addition, this article verified the IAA production ability and cadmium removal ability of urease-producing bacteria, and screened out bifunctional urease-producing bacteria that have potential in cadmium pollution control and plant growth promotion.


Assuntos
Biodegradação Ambiental , Cádmio , Microbiologia do Solo , Poluentes do Solo , Urease , Zea mays , Cádmio/metabolismo , Poluentes do Solo/metabolismo , Zea mays/metabolismo , Urease/metabolismo , China , Ácidos Indolacéticos/metabolismo , Serratia marcescens/fisiologia , Reguladores de Crescimento de Plantas/metabolismo
15.
J Am Chem Soc ; 145(30): 16406-16416, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37432680

RESUMO

Despite tremendous success in understanding the chemical nature and the importance of cation-π interactions in a range of biological processes, particularly in epigenetic regulation, the design and synthesis of stronger cation-π interactions in living cells remain largely elusive. Here, we design several electron-rich Trp derivatives and incorporate them into histone methylation reader domains to enhance the affinity of the reader domains for histone methylation marks via cation-π interactions in living cells. We show that this site-specific Trp replacement strategy is generally applicable for the engineering of high-affinity reader domains for the major histone H3 trimethylation marks, such as H3K4me3, H3K9me3, H3K27me3, and H3K36me3, with high specificity. Furthermore, we demonstrate that engineered reader domains can serve as powerful tools for the enrichment and imaging of histone methylation, as well as for capturing the protein interactome at chromatin marks in living cells. Therefore, our study paves the way for the design of enhanced cation-π interactions in reader proteins in living cells for various biological applications.


Assuntos
Epigênese Genética , Histonas , Histonas/genética , Histonas/metabolismo , Cromatina , Metilação , Código Genético
16.
Invest New Drugs ; 41(1): 13-24, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36331675

RESUMO

Neratinib, an irreversible pan-HER tyrosine kinase inhibitor, has been approved for the treatment of HER2-positive (HER2+) early-stage and brain metastatic breast cancer. Thus far, the pharmacology effects and pharmacodynamics of neratinib have been well studied. However, the disposition of neratinib and its influencing factors in vivo remain unclear. P-glycoprotein (P-gp), one of the most extensively studied transporters, substantially restricts penetration of drugs into the body or deeper compartments (i.e., blood-brain barrier, BBB), regarding drug resistance and drug-drug interactions. Thereby, the aim of this study was to investigate the influence of verapamil (a P-gp inhibitor) on the pharmacokinetics of neratinib in rats. Here, we have established a high specific, selective and sensitive ultra-performance liquid chromatography-tandem mass spectrometric (UPLC-MS/MS) method to quantify plasma concentrations of neratinib in rats. Pharmacokinetic results showed that verapamil significantly increased the system exposure of neratinib, as Cmax increased by 2.09-fold and AUC0-t increased by 1.64-fold, respectively. Additionally, the in vitro transport of neratinib was evaluated using Madin-Darby canine kidney II (MDCK II) and human MDR1 gene overexpressed MDCK (MDCK-MDR1) cell line models. As a result, the net flux ratio was over than 2 and decreased over 50% by verapamil, suggesting that neratinib was a substrate of P-gp. Hence, our findings have highlighted the important role of P-gp in the system exposure of neratinib in vivo, and drug-drug interaction should be considered when coadministration of P-gp inhibitors with neratinib. These findings may support the further clinical development and application of neratinib.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Humanos , Ratos , Animais , Cães , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Verapamil/farmacologia , Cromatografia Líquida , Espectrometria de Massas em Tandem , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo
17.
Chemistry ; 29(71): e202302369, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-37721190

RESUMO

Silicon monoxide (SiO) has attracted great attention due to its high theoretical specific capacity as an alternative material for conventional graphite anode, but its poor electrical conductivity and irreversible side reactions at the SiO/electrolyte interface seriously reduce its cycling stability. Here, to overcome the drawbacks, the dicharged SiO anode coated with Cu coating layer is elaborately designed by in-situ reduction method. Compared with the pristine SiO anode of lithium-ion battery (293 mAh g-1 at 0.5 A g-1 after 200 cycles), the obtained SiO/Cu composite presents superior cycling stability (1206 mAh g-1 at 0.5 A g-1 after 200 cycles). The tight combination of Cu particles and SiO significantly improves the conductivity of the composite, effectively inhibits the side-reaction between the active material and electrolyte. In addition, polypyrrole-coated SiO composites are further prepared by in-situ oxidation method, which delivers a high reversible specific capacity of 1311 mAh g-1 at 0.5 A g-1 after 200 cycles. The in-situ coating strategies in this work provide a new pathway for the development and practical application of high-performance silicon-based anode.

18.
Cell Biol Int ; 47(2): 383-393, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36480792

RESUMO

NUAK1 is a serine/threonine kinase that has been shown to be associated with poor prognosis in several cancers. Although NUAK1 is frequently overexpressed at the transcript level in hepatocellular carcinoma (HCC), the actual role of NUAK1 and the mechanism of its overexpression in HCC has yet to be reported. In the present study, we found that NUAK1 expression was significantly increased in human HCC tumor tissues. Overexpression of NUAK1 dramatically enhanced HCC cells proliferation and migration in vitro. Stable induction of NUAK1 expression promoted tumor growth and tumor metastases to the lungs in the subcutaneous xenograft models and intravenous metastasis models. At the cellular level, enforced expression of Dickkopf-1 (DKK1) activated the Akt signaling pathway, thereby promoting the mRNA and protein expression of NUAK1 in HCC cells. By contrast, depletion of DKK1 was found to attenuate the mRNA and protein expression of NUAK1. In the subcutaneous xenograft models, stable induction of DKK1 expression not only accelerated tumor growth but also increased p-Akt and NUAK1 expression; whereas knockdown of DKK1 inhibited tumor growth, p-Akt and NUAK1 expression. Furthermore, immunohistochemical analysis of 20 HCC clinical samples showed that the expression level of NUAK1 was positively correlated with DKK1 and p-Akt. Taken together, we provide the first evidence that DKK1 promotes NUAK1 transcriptional expression via the activation Akt in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Linhagem Celular Tumoral , RNA Mensageiro , Modelos Animais de Doenças , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética , Proteínas Quinases/metabolismo , Proteínas Repressoras/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo
19.
Scand J Gastroenterol ; 58(9): 1071-1084, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37102215

RESUMO

OBJECTIVE: To systematically evaluate the efficacy and safety of the method of placing the distal stent opening above the duodenal papilla (hereinafter referred to Above method) for endoscopic retrograde stent internal drainage in MBO patients. METHODS: PubMed, Embase, Web of science and Cochrane databases were searched to identify clinical studies comparing the stent distal opening mounted above the papilla and across the papilla (hereinafter referred to Across method), Comparison indicators included stent patency, stent occlusion rate, clinical success rate, overall complication rate, postoperative cholangitis rate, and overall survival. Revman5.4 software was used for meta-analysis, funnel plot and publication bias and Egger's test were completed by Stata14.0 software. RESULTS: A total of 11 clinical studies (8 case-control studies, 3 RCT studies) were included, with a total of 751 patients (318 cases in the Above group and 433 cases Across group). The overall patency of Above method was longer than that of Across method (HR = 0.60, 95%CI [0.46-0.78], p < 0.001). Subgroup analysis showed statistical difference using plastic stent (HR = 0.49, 95%CI [0.33,0.73], p < 0.001). Inversely, there didn't exist significant difference in which metal stent were adopted (HR= 0.74, 95%CI [0.46,1.18], p = 0.21). Similarly, there also without statistical difference between patients with plastic stent placed above the papilla and metal stent mounted Across the papilla (HR = 0.73, 95%CI [0.15,3.65], p = 0.70). Moreover, the overall complication rate of the Above method was lower than that of the Across method (OR = 0.48,95%CI [0.30,0.75], p = 0.002). On the contrary, the differences of stent occlusion rate (OR = 0.86,95%CI [0.51,1.44], p = 0.56), overall survival (HR = 0.90, 95%CI [0.71,1.13]), p = 0.36), the clinical success rate (OR = 1.30, 95%CI [0.52,3.24], p = 0.57) and postoperative cholangitis rats (OR = 0.73, 95%CI [0.34,1.56], p = 0.41) were not statistically significant. CONCLUSIONS: The distal opening of the stent can be placed above the duodenal main papilla for eligible MBO patients who receiving endoscopic retrograde stent drainage treatment, which can effectively prolong the patency duration when plastic stent is used, and reduce the overall risk of complications.


Assuntos
Colangite , Colestase , Neoplasias , Humanos , Animais , Ratos , Colestase/etiologia , Colestase/cirurgia , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Stents/efeitos adversos , Neoplasias/complicações , Drenagem/efeitos adversos , Drenagem/métodos , Colangite/etiologia , Resultado do Tratamento
20.
Environ Res ; 216(Pt 2): 114598, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36257448

RESUMO

BACKGROUND: Although exposure to ambient air pollution has been associated with mental disorder, little is known about its potential effects on children and adolescents, especially in Chinese population. We aimed to reveal the relationship of air pollutants with hospital outpatient visits for child and adolescence psychiatry (HOVCAP) in Shenzhen. METHODS: A case-crossover study based on time-series data was applied, and a distributed lag non-linear model (DLNM) was used to evaluate the non-linear and delayed effects of 4 major air pollutants (NO2, PM2.5, SO2 and O3) on HOVCAP. Least absolute shrinkage and selection operator (LASSO) regression was used to control the multicollinearity between covariates and to filter variables. RESULT: A total of 94,660 cases aged 3-18 were collected from 2014 to 2019 in the Mental Health Center of Shenzhen. Results of pollutants at mode value (M0) showed that in the single lag effect result, when the average daily concentration of NO2 at 24 µg/m3, there was a significant effect on HOVCAP over lag 1, lag 4 and lag 5, respectively. The cumulative RR of NO2 M0 value to the outpatient visits were 1.438 (1.137-1.818) over lag 0-2, 1.454 (1.120-1.887) over lag 0-3, 1.466 (1.084-1.982) over lag 0-4, 1.680 (1.199-2.354) over lag 0-5, 1.993 (1.369-2.903) over lag 0-6, and 2.069 (1.372-3.119) over lag 0-7. However, PM2.5, SO2, O3 were not associated with HOVCAP over neither single lag effects nor cumulative effects. The RR values both shown an increase either when NO2 increases by 10 units or when the maximum concentration of NO2 is reached. CONCLUSION: Our study suggests that exposure to the normal air quality of NO2 in Shenzhen may associated with the risk of HOVCAP. However, PM2.5, SO2, O3 were not associated with HOVCAP.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Psiquiatria , Criança , Adolescente , Humanos , Poluentes Atmosféricos/análise , Estudos Cross-Over , Pacientes Ambulatoriais , Dióxido de Nitrogênio , Poluição do Ar/análise , China/epidemiologia , Hospitais , Material Particulado/análise
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