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1.
ACS Nano ; 18(39): 26784-26798, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39300974

RESUMO

Accurate imaging and precise treatment are critical to controlling the progression of pancreatic cancer. However, current approaches for pancreatic cancer theranostics suffer from limitations in tumor specificity and invasive surgery. Herein, a pancreatic cancer-specific phototheranostic modulator (AuHQ) dominated by aggregation-induced emission (AIE) luminogens-tethered gold nanoparticles is meticulously designed to facilitate prominent fluorescence-photoacoustic bimodal imaging-guided photothermal immunotherapy. Once reaching the pancreatic tumor microenvironment (TME), the peptide Ala-Gly-Phe-Ser-Leu-Pro-Ala-Gly-Cys (AGFSLPAGC) linkage within AuHQ can be specifically cleaved by the overexpressed enzyme Cathepsin E (CTSE), triggering the dual self-assembly of AuNPs and AIE luminogens. The aggregation of AuNPs mediated by enzymatic cleavage results in potentiated photothermal therapy (PTT) under near-infrared (NIR) laser irradiation, induced immunogenic cell death (ICD), and enhanced photoacoustic imaging. Simultaneously, AIE luminogen aggregates formed by hydrophobic interaction can generate AIE fluorescence, enabling real-time and specific fluorescence imaging of pancreatic cancer. Furthermore, coadministration of an indoleamine 2,3-dioxygenase 1 (IDO1) inhibitor with AuHQ can address the limitations of PTT efficacy imposed by the immunosuppressive TME and leverage the synergistic potential to activate systemic antitumor immunity. Thus, this well-designed phototheranostic modulator AuHQ facilitates the intelligent enzymatic dual self-assembly of imaging and therapeutic agents, providing an efficient and precise approach for pancreatic cancer theranostics.


Assuntos
Ouro , Nanopartículas Metálicas , Neoplasias Pancreáticas , Nanomedicina Teranóstica , Ouro/química , Nanopartículas Metálicas/química , Humanos , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/patologia , Camundongos , Animais , Fototerapia , Antineoplásicos/química , Antineoplásicos/farmacologia , Terapia Fototérmica , Linhagem Celular Tumoral , Imagem Óptica , Técnicas Fotoacústicas , Sobrevivência Celular/efeitos dos fármacos
2.
Transl Vis Sci Technol ; 13(9): 2, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39226065

RESUMO

Purpose: The purpose of this study was to compare the clinical efficacy of foldable capsular vitreous body (FCVB) filled with either light or heavy silicone oil and the incidence of complications after their implantation for the treatment of severe ocular trauma and silicone oil-dependent eyes. Methods: FCVB filled with either light (n = 16) or heavy (n = 8) silicone oil was implanted in 24 patients. During the 12-month follow-up period, the intraocular pressure, final best-corrected visual acuity, retinal reattachment condition, position of the FCVB, and complications were assessed. Results: All surgeries were performed without issue. There was no significant difference in preoperative and postoperative best-corrected visual acuity between the two groups. A significant improvement in the intraocular pressure was observed after surgery in both the light silicone oil (P = 0.029) and heavy silicone oil (P = 0.035) groups. None of the patients developed displacement or prolapse of the FCVB. The most common early and late postoperative complications were postoperative hemorrhage (33.3%) and corneal opacification (50%), respectively. Conclusions: FCVB filled with heavy silicone oil can be used as a supplemental therapy for patients who have lost the anterior segment of their eye, have lesions of the inferior retina, or cannot maintain the prone position for various reasons. Translational Relevance: Implantation of FCVB combined with heavy silicone oil compensates for the shortcomings of this with light silicone oil, providing patients with more personalized treatment.


Assuntos
Óleos de Silicone , Acuidade Visual , Corpo Vítreo , Humanos , Óleos de Silicone/uso terapêutico , Óleos de Silicone/efeitos adversos , Masculino , Feminino , Adulto , Corpo Vítreo/efeitos dos fármacos , Pessoa de Meia-Idade , Acuidade Visual/efeitos dos fármacos , Resultado do Tratamento , Adulto Jovem , Vitrectomia/efeitos adversos , Vitrectomia/métodos , Pressão Intraocular/efeitos dos fármacos , Pressão Intraocular/fisiologia , Descolamento Retiniano/cirurgia , Adolescente , Próteses e Implantes/efeitos adversos , Seguimentos , Complicações Pós-Operatórias/etiologia , Idoso , Tamponamento Interno/métodos
3.
J Adv Res ; 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39278567

RESUMO

INTRODUCTION: Pancreatic cancer (PC) remains a challenging malignancy, and adjuvant chemotherapy is critical in improving patient survival post-surgery. However, the intrinsic heterogeneity of PC necessitates personalized treatment strategies, highlighting the need for reliable preclinical models. OBJECTIVES: This study aimed to develop novel patient-derived preclinical PC models using three-dimensional bioprinting (3DP) technology. METHODS: Patient-derived PC models were established using 3DP technology. Genomic and histological analyses were performed to characterize these models and compare them with corresponding patient tissues. Chemotherapeutic drug sensitivity tests were conducted on the PC 3DP models, and correlations with clinical outcomes were analyzed. RESULTS: The study successfully established PC 3DP models with a modeling success rate of 86.96%. These models preserved genomic and histological features consistent with patient tissues. Drug sensitivity testing revealed significant heterogeneity among PC 3DP models, mirroring clinical variability, and potential correlations with clinical outcomes. CONCLUSION: The PC 3DP models demonstrated their utility as reliable preclinical tools, retaining key genomic and histological characteristics. Importantly, drug sensitivity profiles in these models showed potential correlations with clinical outcomes, indicating their promise in customizing treatment strategies and predicting patient prognoses. Further validation with larger patient cohorts is warranted to confirm their potential clinical utility.

4.
Cell Mol Biol Lett ; 29(1): 112, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39169280

RESUMO

BACKGROUND: Breast cancer (BC) ranks as the third most fatal malignant tumor worldwide, with a strong reliance on fatty acid metabolism. CLDN6, a candidate BC suppressor gene, was previously identified as a regulator of fatty acid biosynthesis; however, the underlying mechanism remains elusive. In this research, we aim to clarify the specific mechanism through which CLDN6 modulates fatty acid anabolism and its impact on BC growth and metastasis. METHODS: Cell function assays, tumor xenograft mouse models, and lung metastasis mouse models were conducted to evaluate BC growth and metastasis. Human palmitic acid assay, triglyceride assay, Nile red staining, and oil red O staining were employed to investigate fatty acid anabolism. Reverse transcription polymerase chain reaction (RT-PCR), western blot, immunohistochemistry (IHC) assay, nuclear fractionation, immunofluorescence (IF), immunoprecipitation and acyl-biotin exchange (IP-ABE), chromatin immunoprecipitation (ChIP), dual luciferase reporter assay, and co-immunoprecipitation (Co-IP) were applied to elucidate the underlying molecular mechanism. Moreover, tissue microarrays of BC were analyzed to explore the clinical implications. RESULTS: We identified that CLDN6 inhibited BC growth and metastasis by impeding RAS palmitoylation both in vitro and in vivo. We proposed a unique theory suggesting that CLDN6 suppressed RAS palmitoylation through SREBP1-modulated de novo palmitic acid synthesis. Mechanistically, CLDN6 interacted with MAGI2 to prevent KLF5 from entering the nucleus, thereby restraining SREBF1 transcription. The downregulation of SREBP1 reduced de novo palmitic acid synthesis, hindering RAS palmitoylation and subsequent endosomal sorting complex required for transport (ESCRT)-mediated plasma membrane localization required for RAS oncogenic activation. Besides, targeting inhibition of RAS palmitoylation synergized with CLDN6 to repress BC progression. CONCLUSIONS: Our findings provide compelling evidence that CLDN6 suppresses the palmitic acid-induced RAS palmitoylation through the MAGI2/KLF5/SREBP1 axis, thereby impeding BC malignant progression. These results propose a new insight that monitoring CLDN6 expression alongside targeting inhibition of palmitic acid-mediated palmitoylation could be a viable strategy for treating oncogenic RAS-driven BC.


Assuntos
Neoplasias da Mama , Proliferação de Células , Claudinas , Lipoilação , Proteína de Ligação a Elemento Regulador de Esterol 1 , Animais , Feminino , Humanos , Camundongos , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Claudinas/metabolismo , Claudinas/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Camundongos Nus , Metástase Neoplásica , Proteínas ras/metabolismo , Proteínas ras/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética
5.
Orthop Surg ; 16(8): 1801-1815, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38961661

RESUMO

Poisson's ratio in auxetic materials shifts from typically positive to negative, causing lateral expansion during axial tension. This scale-independent characteristic, originating from tailored architectures, exhibits specific physical properties, including energy adsorption, shear resistance, and fracture resistance. These metamaterials demonstrate exotic mechanical properties with potential applications in several engineering fields, but biomedical applications seem to be one of the most relevant, with an increasing number of articles published in recent years, which present opportunities ranging from cellular repair to organ reconstruction with outstanding mechanical performance, mechanical conduction, and biological activity compared with traditional biomedical metamaterials. Therefore, focusing on understanding the potential of these structures and promoting theoretical and experimental investigations into the benefits of their unique mechanical properties is necessary for achieving high-performance biomedical applications. Considering the demand for advanced biomaterial implants in surgical technology and the profound advancement of additive manufacturing technology that are particularly relevant to fabricating complex and customizable auxetic mechanical metamaterials, this review focuses on the fundamental geometric configuration and unique physical properties of negative Poisson's ratio materials, then categorizes and summarizes auxetic material applications across some surgical departments, revealing efficacy in joint surgery, spinal surgery, trauma surgery, and sports medicine contexts. Additionally, it emphasizes the substantial potential of auxetic materials as innovative biomedical solutions in orthopedics and demonstrates the significant potential for comprehensive surgical application in the future.


Assuntos
Materiais Biocompatíveis , Procedimentos Ortopédicos , Humanos , Procedimentos Ortopédicos/métodos , Materiais Biocompatíveis/uso terapêutico
6.
Molecules ; 29(13)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38999057

RESUMO

Porphyra haitanensis (P. haitanensis), an important food source for coastal residents in China, has a long history of medicinal and edible value. P. haitanensis polysaccharides are some of the main active ingredients in P. haitanensis. It is worth noting that P. haitanensis polysaccharides have a surprising and satisfactory biological activity, which explains the various benefits of P. haitanensis to human health, such as anti-oxidation, immune regulation, anti-allergy, and anticancer properties. Hence, a systematic review aimed at comprehensively summarizing the recent research advances in P. haitanensis polysaccharides is necessary for promoting their better understanding. In this review, we systematically and comprehensively summarize the research progress on the extraction, purification, structural characterization, modification, and biological activity of P. haitanensis polysaccharides and address the shortcomings of the published research and suggest area of focus for future research, providing a new reference for the exploitation of polysaccharides from P. haitanensis in the fields of medicine and functional foods.


Assuntos
Polissacarídeos , Porphyra , Porphyra/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Polissacarídeos/isolamento & purificação , Humanos , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/isolamento & purificação , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/isolamento & purificação
7.
J Am Chem Soc ; 146(27): 18592-18605, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38943624

RESUMO

Ascorbic acid (AA) has been attracting great attention with its emerging potential in T cell-dependent antitumor immunity. However, premature blood clearance and immunologically "cold" tumors severely compromise its immunotherapeutic outcomes. As such, the reversal of the immunosuppressive tumor microenvironment (TME) has been the premise for improving the effectiveness of AA-based immunotherapy, which hinges upon advanced AA delivery and amplified immune-activating strategies. Herein, a novel Escherichia coli (E. coli) outer membrane vesicle (OMV)-red blood cell (RBC) hybrid membrane (ERm)-camouflaged immunomodulatory nanoturret is meticulously designed based on gating of an AA-immobilized metal-organic framework (MOF) onto bortezomib (BTZ)-loaded magnesium-doped mesoporous silica (MMS) nanovehicles, which can realize immune landscape remodeling by chemotherapy-assisted ascorbate-mediated immunotherapy (CAMIT). Once reaching the acidic TME, the acidity-sensitive MOF gatekeeper and MMS core within the nanoturret undergo stepwise degradation, allowing for tumor-selective sequential release of AA and BTZ. The released BTZ can evoke robust immunogenic cell death (ICD), synergistically promote dendritic cell (DC) maturation in combination with OMV, and ultimately increase T cell tumor infiltration together with Mg2+. The army of T cells is further activated by AA, exhibiting remarkable antitumor and antimetastasis performance. Moreover, the CD8-deficient mice model discloses the T cell-dependent immune mechanism of the AA-based CAMIT strategy. In addition to providing a multifunctional biomimetic hybrid nanovehicle, this study is also anticipated to establish a new immunomodulatory fortification strategy based on the multicomponent-driven nanoturret for highly efficient T cell-activation-enhanced synergistic AA immunotherapy.


Assuntos
Antineoplásicos , Ácido Ascórbico , Estruturas Metalorgânicas , Linfócitos T , Animais , Camundongos , Estruturas Metalorgânicas/química , Ácido Ascórbico/química , Ácido Ascórbico/farmacologia , Linfócitos T/imunologia , Linfócitos T/efeitos dos fármacos , Antineoplásicos/química , Antineoplásicos/farmacologia , Imunoterapia , Bortezomib/química , Bortezomib/farmacologia , Bortezomib/uso terapêutico , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Escherichia coli/efeitos dos fármacos , Dióxido de Silício/química , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Magnésio/química , Nanopartículas/química , Humanos , Linhagem Celular Tumoral , Microambiente Tumoral/efeitos dos fármacos , Liberação Controlada de Fármacos
8.
Int J Biol Macromol ; 271(Pt 1): 132617, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38795891

RESUMO

Platycodon grandiflorum (P. grandiflorum) has long been used as a food and traditional herbal medicine. As a food, P. grandiflorum is often transformed into pickles for consumption, and as a traditional Chinese medicine, P. grandiflorum clears the lung, nourishes the pharynx, dispels phlegm, and discharges pus. Polysaccharides are among the main active components of P. grandiflorum. Recent literature has described the preparation, identification, and pharmacological activity of these polysaccharides. Studies have shown that these polysaccharides exhibit a variety of significant biological effects in vitro and in vivo, such as immune stimulation and antioxidant, anti-liver injury, anti-apoptosis and antitumour effects. However, there is no systematic summary of the related research articles on P. grandiflorum polysaccharide, which undoubtedly brings some difficulties to the future research. The purpose of this review is to comprehensively describe research progress on the extraction, purification, structural characterization, modification, and biological activity of P. grandiflorum polysaccharides. The shortcomings of recent research are summarized, further research on their biological activity is proposed to provide new reference value for the application of P. grandiflorum polysaccharides in drugs and health products in the future.


Assuntos
Platycodon , Polissacarídeos , Platycodon/química , Polissacarídeos/farmacologia , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Humanos , Animais , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/farmacologia
9.
iScience ; 27(3): 109138, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38380255

RESUMO

M2 macrophages are associated with the prognosis of bladder cancer. CLDN6 has been linked to immune infiltration and is crucial for predicting the prognosis in multi-tumor. The effect of CLDN6 on M2 macrophages in bladder cancer remains elusive. Here, we compared a total of 40 machine learning algorithms, then selected optimal algorithm to develop M2 macrophages-related signature (MMRS) based on the identified M2 macrophages related module. MMRS predicted the prognosis better than other models and associated to immunotherapy response. CLDN6, as an important variable in MMRS, was an independent factor for poor prognosis. We found that CLDN6 was highly expressed and affected immune infiltration, immunotherapy response, and M2 macrophages polarization. Meanwhile, CLDN6 promoted the growth of bladder cancer and enhanced the carcinogenic effect by inducing polarization of M2 macrophages. In total, CLDN6 is an independent risk factor in MMRS to predict the prognosis of bladder cancer.

11.
Adv Sci (Weinh) ; 11(2): e2304460, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37973557

RESUMO

Methods accurately predicting the responses of colorectal cancer (CRC) and colorectal cancer liver metastasis (CRLM) to personalized chemotherapy remain limited due to tumor heterogeneity. This study introduces an innovative patient-derived CRC and CRLM tumor model for preclinical investigation, utilizing 3d-bioprinting (3DP) technology. Efficient construction of homogeneous in vitro 3D models of CRC/CRLM is achieved through the application of patient-derived primary tumor cells and 3D bioprinting with bioink. Genomic and histological analyses affirm that the CRC/CRLM 3DP tumor models effectively retain parental tumor biomarkers and mutation profiles. In vitro tests evaluating chemotherapeutic drug sensitivities reveal substantial tumor heterogeneity in chemotherapy responses within the 3DP CRC/CRLM models. Furthermore, a robust correlation is evident between the drug response in the CRLM 3DP model and the clinical outcomes of neoadjuvant chemotherapy. These findings imply a significant potential for the application of patient-derived 3DP cancer models in precision chemotherapy prediction and preclinical research for CRC/CRLM.


Assuntos
Bioimpressão , Neoplasias Colorretais , Neoplasias Hepáticas , Humanos , Neoplasias Colorretais/patologia , Prognóstico , Neoplasias Hepáticas/genética
12.
Pharmaceutics ; 15(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38140058

RESUMO

Osteosarcoma, a predominant malignant bone tumor, poses significant challenges due to its high metastatic and recurrent nature. Although various therapeutic strategies are currently in use, they often inadequately target osteosarcoma metastasis. This review focuses on the potential of nanoscale drug delivery systems to bridge this clinical gap. It begins with an overview of the molecular mechanisms underlying metastatic osteosarcoma, highlighting the limitations of existing treatments. The review then transitions to an in-depth examination of nanoscale drug delivery technologies, emphasizing their potential to enhance drug bioavailability and reduce systemic toxicity. Central to this review is a discussion of recent advancements in utilizing nanotechnology for the potential intervention of metastatic osteosarcoma, with a critical analysis of several preclinical studies. This review aims to provide insights into the potential applications of nanotechnology in metastatic osteosarcoma therapy, setting the stage for future clinical breakthroughs and innovative cancer treatments.

13.
Cell Signal ; 112: 110930, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37852424

RESUMO

Colorectal cancer (CRC) is one of the most common cancers in the world. Abnormal proliferation is a chief characteristic of cancer and is the initiation of CRC progression. As an important component of tight junctions, CLDN6 regulates the proliferation of multiple tumors. Our previous study showed that CLDN6 was low expressed in CRC, and CLDN6 overexpression inhibited CRC proliferation. However, the specific mechanism of how CLDN6 works remains unclear. This research aimed to reveal the relationship between CLDN6 and clinical features, as well as the molecular mechanism by which CLDN6 inhibited CRC proliferation. We found that low expression of CLDN6 was associated with pathological grade and prognosis of CRC patients, and confirmed that CLDN6 inhibited CRC proliferation dependent on p53. Mechanically, we elucidated that CLDN6 regulated ubiquitination to enhance p53 stability and nuclear import by PTEN/AKT/MDM2 pathway. Through the PDZ-binding motif (PBM), CLDN6 bound to ZO-1 to interact with PTEN, and regulate AKT/MDM2 pathway. Collectively, our data enriched the theoretical basis for CLDN6 as a potential biomarker for diagnosis, therapy and prognosis of CRC.


Assuntos
Neoplasias Colorretais , Proteína Supressora de Tumor p53 , Humanos , Proteína Supressora de Tumor p53/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias Colorretais/patologia , Ubiquitinação , Proliferação de Células , Linhagem Celular Tumoral , PTEN Fosfo-Hidrolase/metabolismo
14.
Acta Biomater ; 172: 441-453, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37802309

RESUMO

Photothermal therapy (PTT) combined with chemodynamic therapy (CDT) presents an appealing complementary anti-tumor strategy, wherein PTT accelerates the production of reactive oxygen species (ROS) in CDT and CDT eliminates residual tumor tissues that survive from PTT treatment. However, nanomaterials utilized in PTT/CDT are limited by non-specific damage to the entire organism. Herein, a glucose-responsive enzymatic Fe@HRP-ABTS/GOx nanodot is judiciously designed for tumor-specific PTT/CDT via a simple and clean protein-templated biomimetic mineralization synthesis. By oxidizing glucose in tumor cells, glucose oxidase (GOx) activates glucose-responsive tumor therapy and increases the concentration of H2O2 at the tumor site. More importantly, the self-supplied peroxide hydrogen (H2O2) can convert ABTS (2,2'-Hydrazine-bis(3-ethylbenzothiazoline-6-sulfonic acid) diamine salt) into oxidized ABTS (oxABTS) through horseradish peroxidase (HRP) catalysis for PTT and photoacoustic (PA) imaging. Furthermore, the Fe2+ arising from the reduction of Fe3+ by overexpressed GSH reacts with H2O2 to generate intensely reactive •OH through the Fenton reaction, concurrently depleting GSH and inducing efficient tumor CDT. The in vitro and in vivo experiments demonstrate superior cancer cell killing and tumor eradication effect of Fe@HRP-ABTS/GOx nanodot under near-infrared (NIR) laser irradiation. Collectively, the nanodots provide mutually reinforcing catalytic PTT/CDT anti-tumor strategies for treating liver cancer and potentially other malignancies. STATEMENT OF SIGNIFICANCE: Combinatorial antitumor therapy with nanomedicines presents great prospects for development. However, the limitation of non-specific damage to normal tissues hinders its further clinical application. In this work, we fabricated tumor-selective biomimetic Fe@HRP-ABTS/GOx nanodots for H2O2 self-supplied catalytic photothermal/chemodynamic therapy of tumors. The biomimetic synthesis strategy provides the nanodots with enzymatic activity in response to glucose to produce H2O2. The self-supplied H2O2 initiates photothermal therapy with oxidized ABTS and enhances chemodynamic therapy through simultaneous •OH generation and GSH depletion. Our work provides a new paradigm for developing tumor-selective catalytic nanomedicines and will guide further clinical translation of the enzymatic biomimetic synthesis strategy.


Assuntos
Nanopartículas , Neoplasias , Humanos , Biomimética , Peróxido de Hidrogênio , Terapia Fototérmica , Catálise , Glucose , Glucose Oxidase/farmacologia , Peroxidase do Rábano Silvestre , Linhagem Celular Tumoral , Microambiente Tumoral , Nanopartículas/uso terapêutico
15.
Chemistry ; 29(54): e202300913, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37341127

RESUMO

The loading of homogeneous catalysts with support can dramatically improve their performance in olefin polymerization. However, the challenge lies in the development of supported catalysts with well-defined pore structures and good compatibility to achieve high catalytic activity and product performance. Herein, we report the use of an emergent class of porous material-covalent organic framework material (COF) as a carrier to support metallocene catalyst-Cp2 ZrCl2 for ethylene polymerization. The COF-supported catalyst demonstrates a higher catalytic activity of 31.1×106  g mol-1 h-1 at 140 °C, compared with 11.2×106  g mol-1 h-1 for the homogenous one. The resulting polyethylene (PE) products possess higher weight-average molecular weight (Mw ) and narrower molecular weight distribution (Ð) after COF supporting, that is, Mw increases from 160 to 308 kDa and Ð drops from 3.3 to 2.2. The melting point (Tm ) is also increased by up to 5.2 °C. Moreover, the PE product possesses a characteristic filamentous microstructure and demonstrates an increased tensile strength from 19.0 to 30.7 MPa and elongation at break from 350 to 1400 % after catalyst loading. We believe that the use of COF carriers will facilitate the future development of supported catalysts for highly efficient olefin polymerization and high-performance polyolefins.

16.
Artigo em Inglês | MEDLINE | ID: mdl-37094503

RESUMO

PYX-201 is an anti-extra domain B splice variant of fibronectin (EDB + FN) antibody drug conjugate (ADC) composed of a fully human IgG1 antibody, a cleavable mcValCitPABC linker, and four Auristatin 0101 (Aur0101, PF-06380101) payload molecules. To better understand the pharmacokinetic (PK) profile of PYX-201 after it is administered to cancer patients, the development of a reliable bioanalytical assay to accurately and precisely quantitate PYX-201 in human plasma is required. In this manuscript, we present a hybrid immunoaffinity LC-MS/MS assay used to successfully analyze PYX-201 in human plasma. PYX-201 was enriched by MABSelect beads coated with protein A in human plasma samples. The bound proteins were subjected to "on-bead" proteolysis with papain to release the payload Aur0101. The stable isotope labelled internal standard (SIL-IS) Aur0101-d8 was added and the released Aur0101 was quantified as a surrogate for the total ADC concentration. The separation was performed on a UPLC C18 column coupled with tandem mass spectrometry. The LC-MS/MS assay was validated over the range 0.0250 to 25.0 µg/mL with excellent accuracy and precision. The overall accuracy (%RE) was between -3.8% and -0.1% and the inter-assay precision (%CV) was <5.8%. PYX-201 was found to be stable in human plasma for at least 24 h on ice, 15 days after being stored at -80 °C, as well as after five freeze/thaw cycles of being frozen at -25 °C or -80 °C and thawed on ice. The assay this paper reports on, has been successfully applied to human sample analysis to support clinical studies.


Assuntos
Imunoconjugados , Humanos , Cromatografia Líquida/métodos , Imunoconjugados/química , Espectrometria de Massas em Tandem/métodos , Gelo/análise
17.
J Exp Clin Cancer Res ; 42(1): 68, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36935496

RESUMO

BACKGROUND: As a breast cancer suppressor gene, CLDN6 overexpression was found to inhibit breast cancer metastasis in our previous studies, but the specific mechanism remains unclear. This study aimed to clarify the role and mechanism of CLDN6 in inhibiting breast cancer metastasis. METHODS: Western blot, immunofluorescence and transmission electron microscopy were performed to detect autophagy. Wound healing, transwell assays and lung metastasis mouse models were used to examine breast cancer metastasis. Phalloidin staining and immunofluorescent staining were used to observe actin cytoskeleton. mRNA seq, RT-PCR, western blot, chromatin immunoprecipitation, dual luciferase reporter assay, co-immunoprecipitation and immunofluorescence were performed to define the molecular mechanism. The expression levels and clinical implication of CLDN6, WIP and LC3 in breast cancer tissues were evaluated using immunohistochemistry. RESULTS: We demonstrated that CLDN6 inhibited breast cancer metastasis through autophagy in vitro and vivo. We unraveled a novel mechanism that CLDN6 regulated autophagy via WIP-dependent actin cytoskeleton assembly. Through its PDZ-binding motif, overexpressed CLDN6 interacted with JNK and upregulated JNK/c-Jun pathway. C-Jun promoted WIP expression at the transcriptional level. Notably, we observed c-Jun transcriptionally upregulated CLDN6 expression, and there was a positive feedback loop between CLDN6 and JNK/c-Jun. Finally, we found that CLDN6, WIP and LC3 expression correlated with each other, and WIP expression was significantly associated with lymph node metastasis of breast cancer patients. CONCLUSIONS: The data provide a new insight into the inhibitory effects of CLDN6-mediated autophagy on breast cancer metastasis, and revealed the new mechanism of CLDN6 regulating autophagy through WIP-dependent actin cytoskeleton. Our findings enrich the theoretical basis for CLDN6 as a potential biomarker for breast cancer diagnosis and therapy.


Assuntos
Citoesqueleto de Actina , Neoplasias da Mama , Claudinas , Animais , Camundongos , Autofagia , Linhagem Celular Tumoral , Claudinas/genética , Neoplasias da Mama/patologia , Metástase Neoplásica
18.
Bioorg Med Chem ; 78: 117153, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36621179

RESUMO

Several small-molecule covalent inhibitors of KRASG12C have made breakthrough progress in the treatment of KRAS mutant cancer. However, the clinical application of KRASG12C small-molecule inhibitors may be limited by adaptive resistance. Emerging PROTAC strategy can achieve complementary advantages with small molecule inhibitors and improve anti-tumor efficacy. Based on AMG-510, a series of novel KRASG12C-PROTACs were designed and synthesized. The protein degradation assay showed that PROTACs I-1, II-1, III-2 and IV-1 had binding and degradation ability to KRASG12C. III-2 and IV-1 showed potent inhibitory effect on downstream p-ERK and were more potent than AMG-510. Mechanistic studies demonstrated that PROTACs exerted degradation effects through the ubiquitin-proteasome pathway. Using cell lines sensitive to KRASG12C, anti-proliferative activities of compounds were assessed. PROTACs tested showed overall anti-proliferative activities. Besides,the structure-activity relationships (SARs) of KRASG12C-PROTACs were summarized. These results supported the use of the PROTAC strategy to degrade oncogene KRASG12C and provided clues for structural optimization of KRASG12C-PROTACs.


Assuntos
Neoplasias , Quimera de Direcionamento de Proteólise , Humanos , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteólise , Neoplasias/tratamento farmacológico
19.
Neurochem Res ; 48(3): 781-790, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36331667

RESUMO

Neuropathic pain (NP) is a type of chronic pain affecting 6-8% of human health as no effective drug exists. The purinergic 2X4 receptor (P2X4R) is involved in NP. Neohesperidin (NH) is a dihydroflavonoside compound, which has anti-inflammatory and antioxidative properties. This study aimed to investigate whether NH has an effect on P2X4R-mediated NP induced by chronic constriction injury (CCI) of the sciatic nerve in rats. In this study, the CCI rat model was established to observe the changes of pain behaviors, P2X4R, and satellite glial cells (SGCs) activation in dorsal root ganglion (DRG) after NH treatment by using RT-PCR, immunofluorescence double labeling and Western blotting. Our results showed CCI rats had mechanical and thermal hyperalgesia with an increased level of P2X4R. Furthermore, SGCs were activated as indicated by increased expression of glial fibrillary acidic protein and increased tumor necrosis factor-alpha receptor 1and interleukin-1ß. In addition, phosphorylated extracellular regulated protein kinases and interferon regulatory factor 5 in CCI rats increased. After NH treatment in CCI rats, the levels of above protein decreased, and the pain reduced. Overall, NH can markedly alleviate NP by reducing P2X4R expression and SGCs activation in DRG.


Assuntos
Neuralgia , Receptores Purinérgicos P2X4 , Ratos , Humanos , Animais , Ratos Sprague-Dawley , Receptores Purinérgicos P2X4/metabolismo , Neuroglia/metabolismo , Hiperalgesia/metabolismo , Neuralgia/metabolismo , Gânglios Espinais/metabolismo
20.
Org Biomol Chem ; 20(35): 7027-7030, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36017814

RESUMO

We have developed a convenient synthesis of a series of ß-fluoramides in 65% yield. The process involved a tandem fluorination/Ritter reaction to synthesize ß-fluoramides using α-diazo 2H-benzopyran-4-one compounds. Selectfluor was used as the electrophilic fluoride source in acetonitrile to build the ß-fluorinated quaternary carbon center and amide derivatives of 2H-benzopyran-4-one in one step. The products N-(2-(2-fluoro-2,3-dihydro-3-oxobenzofuran-2-yl)propan-2-yl)acetamides were a series of bifunctional compounds with a 2-fluoro-2,3-dihydro-3-oxobenzofuran motif and amide groups.


Assuntos
Acetamidas , Benzopiranos , Diazometano/análogos & derivados , Ácido Egtázico/análogos & derivados , Estrutura Molecular
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