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Tumor metastasis is the major cause of breast cancer morbidity and mortality. It has been reported that the F-box protein FBXO3 functions as an E3 ubiquitin ligase in regulating various biological processes, including host autoimmune, antiviral innate immunity, and inflammatory response. However, the role of FBXO3 in tumor metastasis remains elusive. We have previously shown that ΔNp63α is a common inhibitory target in oncogene-induced cell motility and tumor metastasis. In this study, we show that FBXO3 plays a vital role in PI3K-mediated breast cancer metastasis independent of its E3 ligase activity and ΔNp63α in breast cancer cells and in mouse. FBXO3 can bind to and stabilize USP4, leading to Twist1 protein stabilization and increased breast cancer cell migration and tumor metastasis. Mechanistically, FBXO3 disrupts the interaction between USP4 and aspartyl aminopeptidase (DNPEP), thereby protecting USP4 from DNPEP-mediated degradation. Furthermore, p110αH1047R facilitates the phosphorylation and stabilization of FBXO3 in an ERK1-dependent manner. Knockdown of either FBXO3 or USP4 leads to significant inhibition of PI3K-induced breast cancer metastasis. Clinically, elevated expression of p110α/FBXO3/USP4/Twist1 is associated with poor overall survival (OS) and recurrence-free survival (RFS) of breast cancer patients. Taken together, this study reveals that the FBXO3-USP4-Twist1 axis is pivotal in PI3K-mediated breast tumor metastasis and that FBXO3/USP4 may be potential therapeutic targets for breast cancer treatment.
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Neoplasias da Mama , Melanoma , Neoplasias Cutâneas , Animais , Feminino , Humanos , Camundongos , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Fosfatidilinositol 3-Quinases/metabolismo , Proteína 1 Relacionada a Twist/genética , Proteína 1 Relacionada a Twist/metabolismo , Proteases Específicas de Ubiquitina/metabolismo , UbiquitinaçãoRESUMO
In the realm of condensed matter physics and materials science, charge density waves (CDWs) have emerged as a captivating way to modulate correlated electronic phases and electron oscillations in quantum materials. However, collectively and efficiently tuning CDW order is a formidable challenge. Herein, we introduced a novel way to modulate the CDW order in 1T-TaS2 via stacking engineering. By introducing shear strain during the electrochemical exfoliation, the thermodynamically stable AA-stacked TaS2 consecutively transform into metastable ABC stacking, resulting in unique 3a × 1a CDW order. By decoupling atom coordinates, we atomically deciphered the 3D subtle structural variations in trilayer samples. As suggested by density functional theory (DFT) calculations, the origin of CDWs is presumably due to collective excitations and charge modulation. Therefore, our works shed light on a new avenue to collectively modulate the CDW order via stackingtronics and unveiled novel mechanisms for triggering CDW formation via charge modulation.
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Transforming growth factor-ß (TGF-ß) signaling plays a critical role in promoting epithelial-to-mesenchymal transition (EMT), cell migration, invasion, and tumor metastasis. ΔNp63α, the major isoform of p63 protein expressed in epithelial cells, is a key transcriptional regulator of cell adhesion program and functions as a critical metastasis suppressor. It has been documented that the expression of ΔNp63α is tightly controlled by oncogenic signaling and is frequently reduced in advanced cancers. However, whether TGF-ß signaling regulates ΔNp63α expression in promoting metastasis is largely unclear. In this study, we demonstrate that activation of TGF-ß signaling leads to stabilization of E3 ubiquitin ligase FBXO3, which, in turn, targets ΔNp63α for proteasomal degradation in a Smad-independent but Erk-dependent manner. Knockdown of FBXO3 or restoration of ΔNp63α expression effectively rescues TGF-ß-induced EMT, cell motility, and tumor metastasis in vitro and in vivo. Furthermore, clinical analyses reveal a significant correlation among TGF-ß receptor I (TßRI), FBXO3, and p63 protein expression and that high expression of TßRI/FBXO3 and low expression of p63 are associated with poor recurrence-free survival (RFS). Together, these results demonstrate that FBXO3 facilitates ΔNp63α degradation to empower TGF-ß signaling in promoting tumor metastasis and that the TßRI-FBXO3-ΔNp63α axis is critically important in breast cancer development and clinical prognosis. This study suggests that FBXO3 may be a potential therapeutic target for advanced breast cancer treatment.
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Neoplasias da Mama/patologia , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Feminino , Células HEK293 , Células HaCaT , Humanos , Metástase Neoplásica/patologia , Isoformas de Proteínas , Proteínas Supressoras de Tumor/metabolismoRESUMO
Winlevi® (clascoterone) topical cream (1%, w/w) was approved by the U.S. FDA for the treatment of acne vulgaris in patients 12 years of age and older. The active ingredient, clascoterone, is not stable in physiological solutions and can hydrolyze to cortexolone at body temperature. Instability of clascoterone poses a significant challenge in accurately assessing the rate and extent of clascoterone permeation in vitro. Therefore, the purpose of this study was to develop an in vitro skin permeation test (IVPT) method, and a robust analytical method, that can minimize hydrolyzation of clascoterone during the study for quantification of clascoterone. Two IVPT methods, using either vertical diffusion cells or flow-through cells, were developed and compared to evaluate in vitro permeation of clascoterone from Winlevi. A liquid chromatography with tandem mass spectrometry (LC-MS/MS) method was developed to monitor the level of clascoterone and cortexolone in the IVPT samples. The analytical method features a 2-min high-throughput analysis with good linearity, selectivity, and showed a lower limit of quantitation (LLOQ) of 0.5 ng/mL for both clascoterone and cortexolone. The in vitro skin permeation of clascoterone and cortexolone was observed as early as 2 h in both IVPT methods. A substantive amount of clascoterone was found to hydrolyze to cortexolone when using the vertical static diffusion cells with aliquot sampling. Conversely, degradation of clascoterone was significantly minimized when using the flow-through diffusion cells with fractional sampling. The data enhanced our understanding of in vitro permeation of clascoterone following topical application of the Winlevi topical cream, 1% and underscores the importance of IVPT method development and optimization during product development.
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Cortodoxona , Absorção Cutânea , Creme para a Pele , Espectrometria de Massas em Tandem , Absorção Cutânea/efeitos dos fármacos , Absorção Cutânea/fisiologia , Creme para a Pele/farmacocinética , Creme para a Pele/administração & dosagem , Cortodoxona/administração & dosagem , Cortodoxona/farmacocinética , Cortodoxona/metabolismo , Cortodoxona/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Pele/metabolismo , Administração Cutânea , Cromatografia Líquida/métodos , Animais , Permeabilidade , Suínos , Humanos , PropionatosRESUMO
AMP-activated protein kinase (AMPK) functions as an energy sensor and is pivotal in maintaining cellular metabolic homeostasis. Numerous studies have shown that down-regulation of AMPK kinase activity or protein stability not only lead to abnormality of metabolism but also contribute to tumor development. However, whether transcription regulation of AMPK plays a critical role in cancer metastasis remains unknown. In this study, we demonstrate that AMPKα1 expression is down-regulated in advanced human breast cancer and is associated with poor clinical outcomes. Transcription of AMPKα1 is inhibited on activation of PI3K and HER2 through ΔNp63α. Ablation of AMPKα1 expression or inhibition of AMPK kinase activity leads to disruption of E-cadherin-mediated cell-cell adhesion in vitro and increased tumor metastasis in vivo. Furthermore, restoration of AMPKα1 expression significantly rescues PI3K/HER2-induced disruption of cell-cell adhesion, cell invasion, and cancer metastasis. Together, these results demonstrate that the transcription control is another layer of AMPK regulation and suggest a critical role for AMPK in regulating cell-cell adhesion and cancer metastasis.
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Proteínas Quinases Ativadas por AMP/genética , Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Animais , Mama/patologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Adesão Celular/efeitos dos fármacos , Adesão Celular/genética , Linhagem Celular Tumoral , Cromonas/farmacologia , Intervalo Livre de Doença , Regulação para Baixo , Feminino , Técnicas de Silenciamento de Genes , Humanos , Lapatinib/farmacologia , Camundongos , Morfolinas/farmacologia , Estadiamento de Neoplasias , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Prognóstico , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/metabolismo , Análise Serial de Tecidos , Transcrição Gênica/efeitos dos fármacos , Ativação Transcricional , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
"Through space" palladium/hydrogen shift is an efficient strategy to achieve selective functionalization of a specific remote C-H bond. Compared with relatively extensive exploited 1,4-palladium migration process, the relevant 1,5-Pd/H shift was far less investigated. We herein report a novel 1,5-Pd/H shift pattern between a vinyl and an acyl group. Through the pattern, rapid access to 5-membered-dihydrobenzofuran and indoline derivatives has been achieved. Further studies have unveiled an unprecedented trifunctionalization (vinylation, alkynylation and amination) of a phenyl ring through 1,5-palladium migration relayed decarbonylative Catellani type reaction. A series of mechanistic investigations and DFT calculations have provided insights into the reaction pathway. Notably, it was unveiled that the 1,5-palladium migration in our case prefers a stepwise mechanism involving a PdIV intermediate.
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Adipose tissue dysregulation, a hallmark of obesity, contributes to a chronic state of low-grade inflammation and is associated with increased risk and progression of several breast cancer subtypes, including claudin-low breast tumors. Unfortunately, mechanistic targets for breaking the links between obesity-associated adipose tissue dysfunction, inflammation, and claudin-low breast cancer growth have not been elucidated. Ovariectomized female C57BL/6 mice were randomized (n = 15/group) to receive a control diet, a diet-induced obesity (DIO) diet, or a DIO + resveratrol (0.5% wt/wt) diet. Mice consumed these diets ad libitum throughout study and after 6 weeks were orthotopically injected with M-Wnt murine mammary tumor cells, a model of estrogen receptor (ER)-negative claudin-low breast cancer. Compared with controls, DIO mice displayed adipose dysregulation and metabolic perturbations including increased mammary adipocyte size, cyclooxygenase-2 (COX-2) expression, inflammatory eicosanoid levels, macrophage infiltration, and prevalence of crown-like structures (CLS). DIO mice (relative to controls) also had increased systemic inflammatory cytokines and decreased adipocyte expression of peroxisome proliferator-activated receptor gamma (PPARγ) and other adipogenesis-regulating genes. Supplementing the DIO diet with resveratrol prevented obesity-associated increases in mammary tumor growth, mammary adipocyte hypertrophy, COX-2 expression, macrophage infiltration, CLS prevalence, and serum cytokines. Resveratrol also offset the obesity-associated downregulation of adipocyte PPARγ and other adipogenesis genes in DIO mice. Our findings suggest that resveratrol may inhibit obesity-associated inflammation and claudin-low breast cancer growth by inhibiting adipocyte hypertrophy and associated adipose tissue dysregulation that typically accompanies obesity.
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Tecido Adiposo/efeitos dos fármacos , Anti-Inflamatórios não Esteroides/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Obesidade/tratamento farmacológico , Resveratrol/uso terapêutico , Tecido Adiposo/fisiopatologia , Animais , Neoplasias da Mama/complicações , Neoplasias da Mama/fisiopatologia , Modelos Animais de Doenças , Feminino , Camundongos Endogâmicos C57BL , Obesidade/complicações , Obesidade/fisiopatologia , Pós-MenopausaRESUMO
Triple-negative breast cancer (TNBC) is the most aggressive form of breast cancer. TNBC is often infiltrated with a large number of macrophages, which in turn promote tumor growth and metastasis. In this study, tumor-associated macrophages (TAMs) were exploited as a target to deliver doxorubicin (DOX), a chemotherapeutic agent, to TNBC using nanoparticles surface-functionalized by (i) acid-sensitive sheddable PEGylation and (ii) modifying with mannose (i.e., DOX-AS-M-PLGA-NPs). In mice with orthotopic M-Wnt triple-negative mammary tumors, a single intravenous injection of DOX-AS-M-PLGA-NPs significantly reduced macrophage population in tumors within 2 days, and the density of the macrophages recovered slowly. Repeated injections of DOX-AS-M-PLGA-NPs can help maintain the population of the macrophages at a lower level. In M-Wnt tumor-bearing mice that were pretreated with zoledronic acid to nonselectively deplete macrophages, the TAM-targeting DOX-AS-M-PLGA-NPs were not more effective than the DOX-AS-PLGA-NPs that were not surface-modified with mannose and thus do not target TAMs in controlling tumor growth. However, in M-Wnt tumor-bearing mice that were not pretreated with zoledronic acid, the TAM-targeting DOX-AS-M-PLGA-NPs were significantly more effective than the nontargeting DOX-AS-PLGA-NPs in controlling the tumor growth. The AS-M-PLGA-NPs or other nanoparticles surface-functionalized similarly, when loaded with a chemotherapeutic agent commonly used in adjuvant therapy of TNBC, may be developed into targeted therapy for TNBC.
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Antineoplásicos/farmacologia , Macrófagos/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Linhagem Celular , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/administração & dosagem , Tamanho da Partícula , Polietilenoglicóis/químicaRESUMO
The p53 tumor suppressor gene plays a critical role in regulation of proliferation, cell death and differentiation. The MDM2 oncoprotein is a major negative regulator for p53 by binding to and targeting p53 for proteasome-mediated degradation. The small molecule inhibitor, nutlin-3, disrupts MDM2-p53 interaction resulting in stabilization and activation of p53 protein. We have previously shown that nutlin-3 activates p53, leading to MDM2 accumulation as concomitant of reduced retinoblastoma (Rb) protein stability. It is well known that Rb is important in muscle development and myoblast differentiation and that rhabdomyosarcoma (RMS), or cancer of the skeletal muscle, typically harbors MDM2 amplification. In this study, we show that nutlin-3 inhibited myoblast proliferation and effectively prevented myoblast differentiation, as evidenced by lack of expression of muscle differentiation markers including myogenin and myosin heavy chain (MyHC), as well as a failure to form multinucleated myotubes, which were associated with dramatic increases in MDM2 expression and decrease in Rb protein levels. These results indicate that nutlin-3 can effectively inhibit muscle cell differentiation.
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Diferenciação Celular/efeitos dos fármacos , Imidazóis/farmacologia , Mioblastos/citologia , Mioblastos/efeitos dos fármacos , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteína do Retinoblastoma/metabolismo , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Camundongos , Desenvolvimento Muscular/efeitos dos fármacos , Mioblastos/metabolismo , Proteína do Retinoblastoma/análiseRESUMO
Tumor-associated macrophages (TAMs) are increasingly considered a viable target for tumor imaging and therapy. Previously, we reported that innovative surface-functionalization of nanoparticles may help target them to TAMs. In this report, using poly(lactic-co-glycolic) acid (PLGA) nanoparticles incorporated with doxorubicin (DOX) (DOX-NPs), we studied the effect of surface-modification of the nanoparticles with mannose and/or acid-sensitive sheddable polyethylene glycol (PEG) on the biodistribution of DOX and the uptake of DOX by TAMs in tumor-bearing mice. We demonstrated that surface-modification of the DOX-NPs with both mannose and acid-sensitive sheddable PEG significantly increased the accumulation of DOX in tumors, enhanced the uptake of the DOX by TAMs, but decreased the distribution of DOX in mononuclear phagocyte system (MPS), such as liver. We also confirmed that the acid-sensitive sheddable PEGylated, mannose-modified DOX-nanoparticles (DOX-AS-M-NPs) targeted TAMs because depletion of TAMs in tumor-bearing mice significantly decreased the accumulation of DOX in tumor tissues. Furthermore, in a B16-F10 tumor-bearing mouse model, we showed that the DOX-AS-M-NPs were significantly more effective than free DOX in controlling tumor growth but had only minimum effect on the macrophage population in mouse liver and spleen. The AS-M-NPs are promising in targeting cytotoxic or macrophage-modulating agents into tumors to improve tumor therapy.
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Doxorrubicina/química , Sistemas de Liberação de Medicamentos/métodos , Macrófagos/metabolismo , Nanopartículas/química , Animais , Linhagem Celular Tumoral , CamundongosRESUMO
In recent years, there has been a growing focus on the toxicity and mortality induced by nanoplastics (NPs) in aquatic organisms. However, studies investigating mechanisms underlying oxidative stress (OS), apoptosis, and inflammation induced by NPs in fish remain limited. This study observed that polystyrene NPs (PS-NPs) were accumulated into zebrafish larvae and zebrafish embryonic fibroblast (ZF4 cells), accompanied by the occurrence of pathological damage both at the cellular and tissue-organ level. Additionally, the transcriptional up-regulation of NADPH oxidases (NOXs) and subsequent excessive generation of reactive oxygen species (ROS) resulted in notable changes in the relative mRNA and protein expression levels associated with antioxidant oxidase systems in larvae. Furthermore, the study identified the impact of NPs on mitochondrial ultrastructural, resulting in mitochondrial depolarization and downregulation of mRNA expression related to the electron transport chain due to excessive ROS generation. Short-term exposure to NPs also triggered apoptosis and inflammation in zebrafish larvae, evident from significant up-regulation in mRNA expressions of proapoptotic factors and NF-κB proinflammatory signaling pathway, as well as increased transcription and protein levels of pro-inflammatory factors in larvae. Inhibition of intracellular excessive ROS effectively reduced the induction of apoptosis, NF-κB P65 nuclear migration levels, and cytokine secretion, underscoring OS as a pivotal factor throughout the process of apoptosis and inflammatory responses induced by NPs. This research significantly advances our comprehension of biological effects and underlying mechanisms of NPs in freshwater fish.
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Apoptose , Inflamação , Larva , Poliestirenos , Espécies Reativas de Oxigênio , Poluentes Químicos da Água , Peixe-Zebra , Animais , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Poliestirenos/toxicidade , Inflamação/induzido quimicamente , Larva/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Nanopartículas/toxicidadeRESUMO
This study reports the structure-activity relationships of a unique subclass IIb bacteriocin, plantaricin EvF, which consists of two peptide chains and possesses potent antimicrobial activity. Because the plantaricin Ev peptide chain lacks an α-helix structure, plantaricin EvF is unable to exert its antimicrobial activity through helix-helix interactions like typical subclass IIb bacteriocins. We have shown by various structural evaluation methods that plantaricin Ev can be stabilized by hydrogen bonding at amino acid residues R3, V12, and R13 to the N-terminal region of plantaricin F. This binding gives plantaricin EvF a special spade-shaped structure that exerts antimicrobial activity. In addition, the root-mean-square deviations (RMSDs) of the amino acid residues Y6, F8, and R13 of plantaricin Ev pre- and post-binding were 1.512, 1.723, and 1.369, respectively, indicating that they underwent large structural changes. The alanine scanning experiments demonstrated the important role of the above key amino acids in maintaining the structural integrity of plantaricin EvF. This study not only reveals the unique structural features of plantaricin EvF, but also provides an insight into the structure-activity relationships of subclass IIb bacteriocins.
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In this study, a comprehensive characterization was conducted on a chiral starburst molecule (C57H48N4, SBM) using scanning tunneling microscopy. When adsorbed onto the hBN/Rh(111) nanomesh, these molecules demonstrate homochiral recognition, leading to a selective formation of homochiral dimers. Further tip manipulation experiments reveal that the chiral dimers are stable and primarily controlled by strong intermolecular interactions. Density functional theory (DFT) calculations supported that the chiral recognition of SBM molecules is governed by the intermolecular charge transfer mechanism, different from the common steric hindrance effect. This study emphasizes the importance of intermolecular charge transfer interactions, offering valuable insights into the chiral recognition of a simple bimolecular system. These findings hold significance for the future advancement in chirality-based electronic sensors and pharmaceuticals, where the chirality of molecules can impact their properties.
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For proportionally formulated intermediate strengths of a topical product, the relationship of drug release across multiple strengths of a given product is not always well understood. The current study aims to assess the proportionality of tretinoin release rates across multiple strengths of tretinoin topical gels when manufactured using two different methods to understand the impact of formulation design on drug product microstructure and tretinoin release rate. Two groups of tretinoin gels of 0.04 %, 0.06 %, 0.08 % and 0.1 % strengths were manufactured. Gels in Group I were prepared by incorporating 4-10 % g/g of 1 % w/w tretinoin-loaded microparticles into a gel base. Gels in Group II were manufactured using 10 % g/g of the microparticles that were loaded with increasing amounts (0.4-1 % w/w) of tretinoin. The two groups of gels were characterized by evaluating microstructure using a polarized microscope, rheology using an oscillatory rheometer, and drug release using Vison® Microette™ Hanson vertical diffusion cells. The microscopic images were used to discriminate between the two groups of gels based on the abundance of microparticles in the gel matrix observed in the images. This abundance increased across gels of Group I and was similar across gels of Group II. The rheology parameters, namely viscosity at a shear rate of 10 s-1, shear thinning rate, storage, and loss modulus, increased across gels of Group I, and were not significantly different across gels of Group II. The release rate of tretinoin from the drug products was proportional to the nominal strength of the drug product in both Group I and Group II, with a correlation coefficient of 0.95 in each case, although the absolute release rates differed. Overall, changing the formulation design of tretinoin topical gels containing porous microparticles may change the physicochemical and structural properties, as well as the drug release rate of the product. Further, keeping the formulation design consistent across all strengths of microparticle-based topical gels is important to achieve proportional release rates across multiple strengths of a given drug product.
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Tretinoína , Liberação Controlada de Fármacos , Porosidade , Géis/química , ViscosidadeRESUMO
Hypoxia is a hallmark of cancer development. However, the molecular mechanisms by which hypoxia promotes tumor metastasis are not fully understood. In this study, we demonstrate that hypoxia promotes breast cancer metastasis through suppression of ΔNp63α in a HIF1α-independent manner. We show that hypoxia-activated XBP1s forms a stable repressor protein complex with HDAC2 and EZH2 to suppress ΔNp63α transcription. Notably, H3K27ac is predominantly occupied on the ΔNp63 promoter under normoxia, while H3K27me3 on the promoter under hypoxia. We show that XBP1s binds to the ΔNp63 promoter to recruit HDAC2 and EZH2 in facilitating the switch of H3K27ac to H3K27me3. Pharmacological inhibition or the knockdown of either HDAC2 or EZH2 leads to increased H3K27ac, accompanied by the reduced H3K27me3 and restoration of ΔNp63α expression suppressed by hypoxia, resulting in inhibition of cell migration. Furthermore, the pharmacological inhibition of IRE1α, but not HIF1α, upregulates ΔNp63α expression in vitro and inhibits tumor metastasis in vivo. Clinical analyses reveal that reduced p63 expression is correlated with the elevated expression of XBP1, HDAC2, or EZH2, and is associated with poor overall survival in human breast cancer patients. Together, these results indicate that hypoxia-activated XBP1s modulates the epigenetic program in suppression of ΔNp63α to promote breast cancer metastasis independent of HIF1α and provides a molecular basis for targeting the XBP1s/HDAC2/EZH2-ΔNp63α axis as a putative strategy in the treatment of breast cancer metastasis.
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Neoplasias da Mama , Proteína Potenciadora do Homólogo 2 de Zeste , Epigênese Genética , Histona Desacetilase 2 , Subunidade alfa do Fator 1 Induzível por Hipóxia , Proteínas Supressoras de Tumor , Proteína 1 de Ligação a X-Box , Humanos , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína 1 de Ligação a X-Box/metabolismo , Proteína 1 de Ligação a X-Box/genética , Histona Desacetilase 2/metabolismo , Histona Desacetilase 2/genética , Feminino , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Proteínas Supressoras de Tumor/metabolismo , Proteínas Supressoras de Tumor/genética , Animais , Linhagem Celular Tumoral , Metástase Neoplásica , Camundongos , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Hipóxia Celular/genéticaRESUMO
It is increasingly evident that tumor-associated macrophages (TAMs) play an important role in tumor invasion, proliferation, and metastasis. While delivery of drugs, imaging agents, and vaccines to TAMs was achieved by exploiting membrane receptors on TAMs, the uptake by normal macrophages remains an issue. In this communication, we report a PEG-sheddable, mannose-modified nanoparticle platform that can efficiently target TAMs via mannose-mannose receptor recognition after acid-sensitive PEG shedding in the acidic tumor microenvironment, while their uptake by normal macrophages in the mononuclear phagocyte system (MPS) organs was significantly reduced due to effective PEG shielding at neutral pH. These nanoparticles have the potential to target drugs of interest to TAMs, with decreased uptake by normal macrophages.
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Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Manose/metabolismo , Nanopartículas/química , Nanopartículas/metabolismo , Polietilenoglicóis/química , Lectinas Tipo C/metabolismo , Receptor de Manose , Lectinas de Ligação a Manose/metabolismo , Receptores de Superfície Celular/metabolismoRESUMO
Deep learning networks can be applied to the field of intelligent prediction of part surface roughness. However, the surface roughness samples of parts have the problems of high collection cost, unbalanced categories, and complicated data distribution, which inevitably limit the application of deep learning network models in the field of intelligent prediction of part surface roughness. To solve these problems, this article proposes a novel data augmentation method based on CoralGAN for prediction of part surface roughness, which introduces the domain adaptive method deep coral function to help optimize the network parameters of the generator of generative adversarial network (GAN). Specifically, the vibration signal collected during processing is converted into frequency spectrum data and input into CoralGAN. The training of the generator is guided by coral loss, that is, the distance between the covariances of the real samples and generated samples features, not just the statistical consistency of the traditional GAN. Experiments have been carried out on the three-axis vertical machining center. Research shows that the proposed method can improve the prediction accuracy of part surface roughness to 95.5%.
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In this study, a novel homogeneous mannose-rich polysaccharide named EPS-1 from the fermentation broth of Bifidobacterium breve H4-2 was isolated and purified by anion exchange column chromatography and gel column chromatography. The primary structure of EPS-1 was analyzed by high-performance liquid chromatography, Fourier-transform infrared spectroscopy, gas chromatography-mass spectrometry, and nuclear magnetic resonance. The results indicated that EPS-1 had typical functional groups of polysaccharides. EPS-1 with an average molecular weight of 3.99 × 104 Da was mainly composed of mannose (89.65%) and glucose (5.84%). The backbone of EPS-1 was â2,6)-α-d-Manp-(1â2)-α-d-Manp-(1â2,6)-α-d-Manp-(1â2)-α-d-Manp-(1â2,6)-α-d-Manp-(1â6)-α-d-Glcp-(1â simultaneously containing two kinds of branched chains (α-d-Manp-(1â3)-α-d-Manp-(1â and α-d-Manp-(1â). Besides, EPS-1 had a triple-helical conformation and exhibited excellent thermal stability. Moreover, the immunomodulatory activity of EPS-1 was evaluated by RAW 264.7 cells. Results indicated that EPS-1 significantly enhanced the viability of RAW 264.7 cells. EPS-1 could also be recognized by toll-like receptor 4, thereby activating the nuclear factors-κB (NF-κB) signaling pathway, promoting phosphorylation of related nuclear transcription factors, improving cell phagocytic activity, and promoting the secretion of NO, IL-6, IL-1ß, and TNF-α. Thus, EPS-1 could activate the TLR4-NF-κB signaling pathway to emerge immunomodulatory activity on macrophages. The above results indicate that EPS-1 can serve as a potential immune-stimulating polysaccharide.
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Bifidobacterium breve , Manose , Animais , Camundongos , Manose/metabolismo , Bifidobacterium breve/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Polissacarídeos/química , Macrófagos/metabolismo , Células RAW 264.7 , Peso MolecularRESUMO
OBJECTIVE: This study was conducted to compare the efficacy, tolerability and safety of the modified Atkins diet (MAD) and the classic ketogenic diet (KD) in Chinese children with infantile epileptic spasms syndrome. METHODS: We retrospectively recruited and analyzed 56 children with infantile epileptic spasms syndrome started on the MAD (n = 21) and classic KD (n = 35) at our institution from June 2016 to July 2022. RESULTS: The MAD group had exhibited comparable rates of spasm reduction (>50%) as the classic KD group at the time point of 3 months (66.7% for MAD, 75% for KD; p = 0.510), 6 months (75% for MAD, 82.6% for KD; p = 0.694), and 12 months (84.6% for MAD, 90.9% for KD; p = 1.000). The probability of patients remaining on the MAD was higher (p = 0.048) than those consuming the classic KD. By analyzing discontinuation reasons, we found that the MAD patients had a lower rate of poor compliance than the classic KD patients (p = 0.014). Response to the diet at 1 month and fewer anti-seizure medicines (ASMs) had tried before KD initiation were possible factors in regard to likelihood of spasm-free response to the diet therapy at 3 months (p = 0.001 and p = 0.014, respectively). CONCLUSIONS: The efficacy of spasm control was similar in the MAD, with better tolerability and higher compliance compared to the classic KD. Therefore, MAD could be the primary treatment for children in China with- infantile epileptic spasms syndrome. Additionally, an earlier beginning of the diet treatment may have significant advantages.