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1.
Nano Lett ; 23(18): 8674-8682, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37721331

RESUMO

The VEGF-VEGFR2 (VEGF = vascular endothelial growth factor) signaling has been a promising target in cancer therapy. However, because conventional anti-angiogenic therapeutics suffer from drawbacks, particularly severe side effects, novel anti-angiogenic strategies are much needed. Herein, we report the rational engineering of VEGF-targeted molecularly imprinted polymer nanoparticles (nanoMIP) for anti-angiogenic cancer therapy. The anti-VEGF nanomedicine was prepared via a state-of-the-art molecular imprinting approach using the N-terminal epitope of VEGF as the template. The nanoMIP could target the two major pro-angiogenic isoforms (VEGF165 and VEGF121) with high affinity and thereby effectively block the VEGF-VEGFR2 signaling, yielding a potent anti-angiogenic effect of "killing two birds with one stone". In vivo experiments demonstrated that the anti-VEGF nanoMIP effectively suppressed tumor growth via anti-angiogenesis in a xenograft model of human colon carcinoma without apparent side effects. Thus, this study not only proposes an unprecedented anti-angiogenic strategy for cancer therapy but also provides a new paradigm for the rational development of MIPs-based "drug-free" nanomedicines.

2.
Angew Chem Int Ed Engl ; 62(17): e202301202, 2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-36814079

RESUMO

Harnessing innate immunity is an appealing strategy for cancer treatment. Herein, we report a new strategy called molecularly imprinted nanobeacons (MINBs) for redirecting innate immune killing towards triple-negative breast cancer (TNBC). The MINBs were molecularly imprinted nanoparticles with the N-epitope of glycoprotein nonmetastatic B (GPNMB) as the template and grafted with plentiful fluorescein moieties as the hapten. The MINBs could tag the TNBC cells via binding with GPNMB and thereby provide navigation for recruiting hapten-specific antibodies. The gathered antibodies could further trigger effective Fc-domain-mediated immune killing towards the tagged cancer cells. In vivo experiments showed that the TNBC growth was significantly inhibited after MINBs treatment by intravenous injection as compared with control groups. This study not only opens a new access for redirecting innate immunity towards TNBC but also paves the way for innate immunity-based therapy of other diseases.


Assuntos
Nanopartículas , Neoplasias de Mama Triplo Negativas , Humanos , Anticorpos , Linhagem Celular Tumoral , Glicoproteínas de Membrana , Impressão Molecular , Neoplasias de Mama Triplo Negativas/patologia , Imunidade Inata
3.
Anal Chem ; 94(20): 7375-7382, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35544739

RESUMO

The ATP-binding cassette, subfamily G, isoform 2 protein (ABCG2), as an important member of ABC transporters, plays a key role in multidrug resistance (MDR) in cancer and has been widely considered as a marker of cancer stem cells (CSC). Reagents capable of simultaneously targeting ABCG2 and reversing MDR have great clinical application values, but their development is highly challenging. Herein, ABCG2 glycosylated extracellular region-binding aptamers were efficiently screened by a cladded molecularly imprinted polymer (cMIP)-based in vitro screening method and further rationally engineered into cyclic bivalent aptamers. Experiments showed that both the monovalent and cyclic bivalent aptamers could specifically bind ABCG2 and thereby specially target CSC of human colorectal carcinomas (CoCSC), while the latter could effectively reverse MDR in drug-resistant liver cancer cells (HepG2/ADR). Different from currently predominant small molecule inhibitors, the reversal of MDR relied on a different mechanism; the cyclic bivalent aptamers bound the two monomers of ABCG2 dimers simultaneously and thereby blocked the ABCG2-mediated drug-pumping channel, resulting in increased intracellular accumulation of substrate drugs. This study opened a new access to the development of affinity reagents for targeting CSC and reversing MDR, holding great prospects in cancer diagnosis and treatment.


Assuntos
Antineoplásicos , Neoplasias , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Humanos , Proteínas de Neoplasias/metabolismo , Células-Tronco Neoplásicas/metabolismo
4.
Small ; 18(46): e2201671, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36161701

RESUMO

Exploring new targets and developing novel targeted therapies are urgently needed for neuroblastoma therapy. Polysialic acid (polySia), a linear homopolymer of sialic acid units that correlates well with tumor progression and poor prognosis, has emerged as a potential target for neuroblastoma. However, the lack of polySia-specific binding reagents has severely limited the development of polySia-targeting therapeutics for neuroblastoma. Herein, the construction of polySia-targeting nanomissiles via molecular imprinting for the photothermal therapy of neuroblastoma is reported. Oligosialic acid (oligoSia) containing 3-4 units is considered as a characteristic structure for the recognition of polySia, while oligoSia containing 4-7 units digested from polySia is employed as the template. Via boronate-affinity controllable oriented surface imprinting, oligoSia-imprinted nanoparticles (oSia-MIP) are prepared. The oSia-MIP allows for specifically recognizing polySia and targeting polySia overexpressed neuroblastoma cells in vitro and in vivo. oSia-MIP loaded with indocyanine green is prepared and experimentally demonstrated to be a potent targeted photothermal therapeutic for neuroblastoma. Equipping the core substrate with functional entities, the developed polySia targeting nanoplatform can be accommodated to various therapeutic modalities, holding great promise for neuroblastoma targeted therapy.


Assuntos
Neuroblastoma , Terapia Fototérmica , Humanos , Ácidos Siálicos/química , Ácidos Siálicos/metabolismo , Neuroblastoma/terapia , Ácido N-Acetilneuramínico
5.
Angew Chem Int Ed Engl ; 61(21): e202113528, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35194906

RESUMO

The glycosylation pattern of alpha fetoprotein (AFP) paves the basis for precise early diagnosis of hepatocellular carcinoma (HCC). However, existing analytical methods ignore the contribution of terminal sialic acid, which has been reported to be highly connected with HCC. Besides, the development of diagnostic assays is severely hindered by the preparation of anti-glycans antibodies. Molecularly imprinted polymers (MIPs), as synthetic antibody mimics, provide unique strengths to address these issues. Herein, we report a MIPs-based dual-modal ratiometric immunoassay for precise HCC diagnosis. Using a "pit one against ten" MIP to recognize a subset of glycans containing sialic acid and/or core fucose, we demonstrated our assay exhibited improved precision as compared with ELISA. This assay provided not only a glycoform-resolved method for precise HCC diagnosis, but also a new paradigm for developing antibody mimics via molecular imprinting towards challenging biomedical applications.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Impressão Molecular , Anticorpos , Carcinoma Hepatocelular/diagnóstico , Humanos , Imunoensaio/métodos , Neoplasias Hepáticas/diagnóstico , Impressão Molecular/métodos , Polímeros Molecularmente Impressos , Ácido N-Acetilneuramínico
6.
Angew Chem Int Ed Engl ; 60(8): 3858-3869, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-32789971

RESUMO

Molecularly imprinted polymers (MIPs) are chemically synthesized affinity materials with tailor-made binding cavities complementary to the template molecules in shape, size, and functionality. Recently, engineering MIP-based nanomedicines to improve cancer therapy has become a rapidly growing field and future research direction. Because of the unique properties and functions of MIPs, MIP-based nanoparticles (nanoMIPs) are not only alternatives to current nanomaterials for cancer therapy, but also hold the potential to fill gaps associated with biological ligand-based nanomedicines, such as immunogenicity, stability, applicability, and economic viability. Here, we survey recent advances in the design and fabrication of nanoMIPs for cancer therapy and highlight their distinct features. In addition, how to use these features to achieve desired performance, including extended circulation, active targeting, controlled drug release and anti-tumor efficacy, is discussed and summarized. We expect that this minireview will inspire more advanced studies in MIP-based nanomedicines for cancer therapy.


Assuntos
Polímeros Molecularmente Impressos/química , Nanopartículas/química , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Humanos , Nanomedicina , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Receptores de Superfície Celular/antagonistas & inibidores , Receptores de Superfície Celular/metabolismo
7.
Angew Chem Int Ed Engl ; 60(5): 2663-2667, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33078504

RESUMO

Prodrug and drug delivery systems are two effective strategies for improving the selectivity of chemotherapeutics. Molecularly imprinted polymers (MIPs) have emerged as promising carriers in targeted drug delivery for cancer treatment, but they have not yet been integrated with the prodrug strategy. Reported here is an MIP-based smart prodrug delivery system for specific targeting, prolonged retention time, and tumor microenvironment-triggered release. 5'-Deoxy-5-fluorocytidine (DFCR) and sialic acid (SA) were used as a prodrug and a marker for tumor targeting, respectively. Their co-imprinted nanoparticles were prepared as a smart carrier. Prodrug-loaded MIP specifically and sustainably accumulated at the tumor site and then gradually released. Unlike conventional prodrug designs, which often require in-liver bioconversion, this MIP-based prodrug delivery is liver-independent but tumor-dependent. Thus, this study opens new access to the development of smart prodrug delivery nanoplatforms.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Polímeros Molecularmente Impressos/química , Pró-Fármacos/química , Humanos , Microambiente Tumoral
8.
J Microencapsul ; 36(1): 21-31, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30757946

RESUMO

The purpose of this study was to investigate the influences of drying methods on the risperidone (RIS) release profiles of RIS-loaded PLGA microspheres. These microspheres were fabricated with an O/W emulsion solvent evaporation method. The wet microspheres were dried with freeze drying and vacuum drying methods. The microspheres were mono-dispersed spheres with an average diameter of 100 µm. Studies found that drying methods had great influence on the porosity, morphology, and release profiles of RIS-loaded PLGA microspheres. Specifically, the freeze-dried microspheres had higher porosity (78.46 ± 1.64%) than those vacuum-dried ones (52.45 ± 2.68%), and they showed higher RIS release rates (p < 0.05). In the accelerated release tests (45 °C), these microspheres dried under the pressures of 700 mmHg and 200 mmHg gave faster release rates than those ones dried under the pressure of 450 mmHg. Importantly, the accelerated release test (45 °C) had a high correlation with the real-time test (37 °C) (R2 > 0.99). These studies exhibited a significance in the precise preparation of RIS-loaded PLGA microspheres.


Assuntos
Portadores de Fármacos/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Risperidona/química , Antagonistas da Serotonina/química , Dessecação , Composição de Medicamentos , Liberação Controlada de Fármacos , Liofilização , Cinética , Porosidade , Risperidona/administração & dosagem , Antagonistas da Serotonina/administração & dosagem
9.
Biomacromolecules ; 15(11): 4281-92, 2014 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-25325531

RESUMO

The application of PEG-b-PCL micelles was dampened by their inherent low drug-loading capability and relatively poor cell uptake efficiency. In this study, a series of novel PEG-b-PCL copolymers methoxy poly(ethylene glycol)-b-poly(ε-caprolactone-co-γ-dimethyl maleamidic acid -ε-caprolactone) (mPEG-b-P(CL-co-DCL)) bearing different amounts of acid-labile ß-carboxylic amides on the polyester moiety were synthesized. The chain structure and chemical composition of copolymers were characterized by (1)H NMR, Fourier transform infrared spectroscopy (FT-IR), and gel permeation chromatography (GPC). mPEG-b-P(CL-co-DCL) with critical micellar concentrations (CMCs) of 3.2-6.3 µg/mL could self-assemble into stable micelles in water with diameters of 100 to 150 nm. Doxorubicin (DOX), a cationic hydrophobic drug, was successfully encapsulated into the polymer micelles, achieving a very high loading content due to electrostatic interaction. Then the stability, charge-conversional behavior, loading and release profiles, cellular uptake and in vitro cytotoxicity of free drug and drug-loaded micelles were evaluated. The ß-carboxylic amides functionalized polymer micelles are negatively charged and stable in neutral solution but quickly become positively charged at pH 6.0, due to the hydrolysis of ß-carboxylic amides in acidic conditions. The pH-triggered negative-to-positive charge reversal not only resulted in a very fast drug release in acidic conditions, but also effectively enhanced the cellular uptake by electrostatic absorptive endocytosis. The MTT assay demonstrated that mPEG-b-P(CL-co-DCL) micelles were biocompatible to HepG2 cells while DOX-loaded micelles showed significant cytotoxicity. In sum, the introduction of acid-labile ß-carboxylic amides on the polyester block in mPEG-b-P(CL-co-DCL) exhibited great potentials for the modifications in the stability in blood circulation, drug solubilization, and release properties, as well as cell internalization and intracellular drug release.


Assuntos
Doxorrubicina/química , Sistemas de Liberação de Medicamentos/métodos , Líquido Intracelular/efeitos dos fármacos , Lactonas/química , Micelas , Polietilenoglicóis/química , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Doxorrubicina/administração & dosagem , Doxorrubicina/metabolismo , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Líquido Intracelular/metabolismo , Lactonas/administração & dosagem , Lactonas/metabolismo , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/metabolismo , Propriedades de Superfície/efeitos dos fármacos
10.
J Mater Sci Mater Med ; 24(2): 333-41, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23138838

RESUMO

To improve the poor compatibility among different components of Drug-in-adhesive type patch, two novel plasters (Drug-in-fiber and Drug-in-adhesive/fiber) were developed based on ibuprofen (IBU)-loaded fiber mats. These fibrous mats were fabricated via electrospinning of cellulose acetate/poly(vinylpyrrolidone) composites in a binary solvent of N,N-dimethyl acetamide/acetone. Physical status studies suggested that Drug-in-fiber could inhibit IBU re-crystallization, but the active ingredients were released at a relatively slow rate due to the dual-resistance of fiber mat and adhesive matrix. To overcome this shortcoming, Drug-in-adhesive/fiber was designed by coupling medicated hydrophilic pressure sensitive adhesive and IBU-loaded fiber mat. This method endowed Drug-in-adhesive/fiber a fast IBU release rate and high permeated drug amount though simulative skins. This design separated enhancer from adhesive matrix, which guaranteed Drug-in-adhesive/fiber excellent adhesion forces. Hence, the plasters based on medicated fiber mats improved the compatibility among patch components.


Assuntos
Celulose/análogos & derivados , Portadores de Fármacos/síntese química , Ibuprofeno/administração & dosagem , Polímeros/síntese química , Povidona/química , Adesivo Transdérmico , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacocinética , Células Cultivadas , Celulose/química , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Desenho de Fármacos , Técnicas Eletroquímicas/métodos , Ibuprofeno/farmacocinética , Teste de Materiais , Membranas Artificiais , Modelos Biológicos , Polímeros/química , Pele/efeitos dos fármacos , Pele/metabolismo , Suínos
11.
Chem Sci ; 14(10): 2553-2561, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36908957

RESUMO

Cis-diol metabolic reprogramming evolves during primary liver cancer (PLC) initiation and progression. However, owing to the low concentrations and highly structural heterogeneity of cis-diols in vivo, severe interference from complex biofluids and limited profiling coverage of existing methods, in-depth profiling of cis-diol metabolites and linking their specific changes with PLC remain challenging. Besides, due to the low specificity of widely used protein biomarkers, accurate classification of PLC from hepatitis still represents an unmet need in clinical diagnostics. Herein, to high-coverage profile cis-diols and explore the translational potential of them as biomarkers, a machine learning-empowered boronate affinity extraction-solvent evaporation assisted enrichment-mass spectrometry (MLE-BESE-MS) was developed. A single analytical platform integrated with multiple complementary functions, including pH-controlled boronate affinity extraction, solvent evaporation-assisted enrichment and nanoelectrospray ionization-based cis-diol identification, was constructed, which significantly improved the metabolite coverage. Meanwhile, by virtue of machine learning (principal components analysis, orthogonal partial least-squares discrimination analysis and random forest), collected cis-diols were statistically screened to extract efficient features for precise PLC diagnosis, and the results outperform the routinely used protein biomarker-based methods both in sensitivity (87.5% vs. less than 70%) and specificity (85.7% vs. ca. 80%). This machine learning-empowered integrated MS platform advanced the targeted metabolic analysis for early cancer diagnosis, rendering great promise for clinical translation.

12.
ACS Appl Mater Interfaces ; 15(23): 27658-27669, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37267068

RESUMO

Reprogramming tumor-associated macrophages (TAMs) has emerged as a promising strategy in cancer immunotherapy. Targeted therapeutics integrating multiple functions to fully leverage the antitumor immune functions of macrophages without affecting systemic or tissue-resident macrophages are crucial for TAM reprogramming. Herein, by integrating molecular imprinting and nanotechnology, we rationally designed and engineered an unprecedented nanocoordinator for targeted remolding of TAMs to fully leverage the antitumor efficacy of macrophages by inducing a cascade effect. The nanocoordinator features a magnetic iron oxide nanoinner core and sialic acid-imprinted shell. Intravenously administered into systemic circulation, the nanocoordinator can rapidly accumulate at the tumor site in response to an external magnet. Then, by specifically binding to sialic acid overexpressed on tumor cells, the nanocoordinator anchors at the tumor site with prolonged retention time. Via binding with the nanocoordinator, tumor cells are tagged with a foreign substance, which promotes the intrinsic phagocytosis of macrophages. Subsequently, the nanocoordinator taken up by macrophages effectively promotes the polarization of macrophages toward the M1 phenotype, thus activating the immunotherapeutic efficacy of macrophages. Synergized by the cascade effect, this nanocoordinator effectively harnesses TAMs for macrophage-mediated immunotherapy. This study offers new TAM-targeted therapeutics that allows us to fully leverage the antitumor immune functions of macrophages without affecting the normal tissue.


Assuntos
Ácido N-Acetilneuramínico , Neoplasias , Humanos , Ácido N-Acetilneuramínico/metabolismo , Macrófagos , Neoplasias/tratamento farmacológico , Fagocitose , Imunoterapia , Microambiente Tumoral
13.
Adv Sci (Weinh) ; 10(2): e2202689, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36377484

RESUMO

Infectious virus diseases, particularly coronavirus disease 2019, have posed a severe threat to public health, whereas the developed therapeutic and prophylactic strategies are seriously challenged by viral evolution and mutation. Therefore, broad-spectrum inhibitors of viruses are highly demanded. Herein, an unprecedented antiviral strategy is reported, targeting the viral glycan shields with hypervalent mannose-binding nanoparticles. The nanoparticles exhibit a unique double-punch mechanism, being capable of not only blocking the virus-receptor interaction but also inducing viral aggregation, thereby allowing for inhibiting the virus entry and facilitating the phagocytosis of viruses. The nanoparticles exhibit potent and broad-spectrum antiviral efficacy to multiple pseudoviruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its major variants (D614G, N501Y, N439K, Δ69-70, Delta, and Omicron; lentiviruses expressing only the spike proteins), as well as other vital viruses (human immunodeficiency virus 1 and Lassa virus), with apparent EC50 values around the 10-9  m level. Significantly, the broad-spectrum inhibition of authentic viruses of both wild-type SARS-CoV-2 and Delta variants is confirmed. Therefore, this hypervalent glycan-shield targeting strategy opens new access to broad-spectrum viral inhibition.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Antivirais/farmacologia , Polissacarídeos/metabolismo
14.
Chem Sci ; 13(36): 10897-10903, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36320712

RESUMO

Blocking the PD-1/PD-L1 immune checkpoint has emerged as a promising strategy in cancer immunotherapy, in which monoclonal antibodies are predominately used as inhibitors. Despite their remarkable success, monoclonal antibody-based therapeutics suffer from drawbacks due to the use of antibodies, such as high cost, low stability and high frequency of immune-related adverse effects. Therefore, novel anti-PD-1/PD-L1 therapeutics that can address these issues are of significant importance. Herein, we report a molecularly imprinted polymer (MIP) based PD-1 nano inhibitor for blocking the PD-1/PD-L1 axis. The anti-PD-1 nanoMIP was rationally designed and engineered by epitope imprinting using the N-terminal epitope of PD-1 as the binding site. The anti-PD-1 nanoMIP showed good specificity and high affinity towards PD-1, yielding a disassociation constant at the 10-8 M level, much better than that between PD-1 and PD-L1. Via steric hindrance, this inhibitor could effectively block PD-1/PD-L1 interaction. Besides, it could effectively reactivate T cells and reverse the chemoresistance of tumor cells. Therefore, this present study not only provides a novel and promising immune checkpoint blockade inhibitor but also boosts further development of MIPs for cancer immunotherapy.

15.
Chem Sci ; 13(16): 4589-4597, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35656127

RESUMO

Accurately analysing the particular glycosylation status of protein biomarkers is of significant importance in the precise, early diagnosis of cancer. Existing methods mainly rely on the use of antibodies and lectins. However, due to the macroscopic and microscopic heterogeneity of glycans, precise analysis of glycosylation status still remains a challenge. Molecularly imprinted polymers (MIPs), as a synthetic alternative to antibodies or lectins, may provide new solutions but have not yet been explored. Herein, we report an appealing strategy called triple MIP-based plasmonic immunosandwich assay (triMIP-PISA) for precise cancer diagnosis in terms of the relative glycosylation expression of glycoprotein biomarkers. As proof of the principle, alpha fetoprotein (AFP), which has been used as a clinical biomarker for early detection of hepatocellular carcinoma (HCC), as well as its Lens culinaris agglutinin (LCA)-reactive fraction (AFP-L3), which is mainly composed of core-fucosylated glycans, were used as two target proteoforms to test in this study. Using two MIPs that can specifically recognize the peptide sequence of AFP as well as a fucose-imprinted MIP that can specifically recognize the AFP-L3 fraction, facile simultaneous plasmon-enhanced Raman detection of AFP and AFP-L3 in serum was achieved, which allowed HCC patients to be distinguished from healthy individuals. Due to the excellent recognition properties of the MIPs that are comparable to those of antibodies and superior to those of lectins, our triMIP-PISA method exhibited improved precision as compared with an antibody plus lectin-based immunofluorescence assay. Thus, this strategy opened a new avenue towards the precise diagnosis of cancer.

16.
ACS Appl Mater Interfaces ; 14(39): 44098-44110, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36149803

RESUMO

Chemodynamic therapy (CDT) that kills tumor cells by converting low-reactivity H2O2 into highly toxic hydroxyl radicals (•OH) is an emerging tumor therapeutic modality, but its therapeutic efficacy is largely limited by both the lack of tumor targeting and redox homeostasis in tumor cells. Herein, we report Cu2+-encapsulated and GalNAc-imprinted biodegradable silica nanoparticles (nanoMIP) for boosting CDT. In this strategy, the Cu2+ was first encapsulated into disulfide-bridged silica nanoparticles with a high loading capacity of ∼18.3%, followed by in situ functionalization via molecular imprinting using GalNAc as a template. Such a nanovector could specifically target tumor cells overexpressing the Tn antigen to promote the cellular uptake. After internalization into tumor cells, the degradation of nanoMIP occurred in response to the tumor microenvironment, spontaneously releasing Cu2+/Cu+ via redox cycles, which in turn promoted highly potent GSH depletion and triggered •OH generation by a Fenton-like reaction. Notably, we found that the catalase activity could be effectively inhibited by the produced Cu+, which indirectly upregulated the endogenous H2O2 level. As a result, the "maladjusted" tumor cells lost the resistance against •OH damage, finally resulting in the apoptosis of tumor cells. In vitro and in vivo experiments demonstrated that our nanoMIP exhibited excellent cytotoxicity against tumor cells and high efficacy of tumor inhibition in the xenograft tumor model with negligible side effects. Taken together, our study provides not only a promising strategy for maximizing the CDT efficacy but also a new insight for developing MIP-based nanomedicine.


Assuntos
Nanopartículas , Neoplasias , Catalase/metabolismo , Linhagem Celular Tumoral , Dissulfetos/farmacologia , Homeostase , Humanos , Peróxido de Hidrogênio/metabolismo , Nanopartículas/uso terapêutico , Neoplasias/terapia , Oxirredução , Dióxido de Silício/farmacologia , Microambiente Tumoral
17.
Polymers (Basel) ; 15(1)2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36616392

RESUMO

Resin-impregnated paper (RIP) bushing has gained significant interest due to its extended application in Extra High Voltage (EHV) and Ultra High Voltage (UHV) electricity transmission systems. However, the design criterion of its overall structure, the geometry parameters of the condenser layers, and stress release devices, etc., are still not fully understood. This article proposes a unique electric field optimization technique to integrate both the analytical and the numerical methods. The charge simulation method (CSM) is employed to create the overall equipotential surface, within which the finite element analysis (FEA) is adapted to study the localized field enhancement effects, taking into consideration the multi-physics coupled fields. A case study is performed on an actual UHV bushing. The results are compared to the traditional methods, to demonstrate the benefit of the hybrid method.

18.
J Biomater Sci Polym Ed ; 32(17): 2293-2305, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34429025

RESUMO

For the past few years, organic-inorganic hybrid nanocarriers have been widely explored for effective drug delivery and preferable disease treatments. In this article, hydrothermal method was utilized to prepare fine dispersed layered double hydroxide (Mg-Al LDH) suspension. Polyethylene glycol (PEG) was grafted on the surface of LDH lamella in order to improve the dispersibility of LDH. Besides, the anti-cancer drug gemcitabine was grafted on the surface of LDH lamellas through chemical grafting. Hence a novel new type of organic-inorganic hybrid drug delivery system LDH-mPEG-Gemcitabine was obtained. In addition, the siRNA was intercalated into the LDH interlamination by ion exchange method to realize drug and gene co-delivery. The loading capacity of LDH and LDH-mPEG-Gemcitabine was evaluated by agarose gel electrophoresis. The characterization by laser particle size analyzer, TEM, FT-IR, XRD, in vitro cell viability and in vitro drug release demonstrated that LDH-mPEG-Gemcitabine possessed fine dispersibility, uniform morphology and particle size, fine biocompatibility, ideal drug loading and releasing capacity and held great potential to be used as a desired co-delivery system for drug and gene.


Assuntos
Hidróxidos , Polietilenoglicóis , Desoxicitidina/análogos & derivados , Sistemas de Liberação de Medicamentos , Espectroscopia de Infravermelho com Transformada de Fourier , Gencitabina
19.
ACS Nano ; 15(11): 18214-18225, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34664930

RESUMO

Although protein therapeutics is of significance in therapeutic intervention of cancers, controlled delivery of therapeutic proteins still faces substantial challenges including susceptibility to degradation and denaturation and poor membrane permeability. Herein, we report a sialic acid (SA)-imprinted biodegradable silica nanoparticles (BS-NPs)-based protein delivery strategy for targeted cancer therapy. Cytotoxic ribonuclease A (RNase A) was effectively caged in the matrix of disulfide-hybridized silica NPs (encapsulation efficiency of ∼64%), which were further functionalized with cancer targeting capability via surface imprinting with SA as imprinting template. Such nanovectors could not only maintain high stability in physiological conditions but also permit redox-triggered biodegradation for both concomitant release of the loaded therapeutic cargo and in vivo clearance. In vitro experiments confirmed that the SA-imprinted RNase A@BS-NPs could selectively target SA-overexpressed tumor cells, promote cells uptake, and subsequently be cleaved by intracellular glutathione (GSH), resulting in rapid release kinetics and enhanced cell cytotoxicity. In vivo experiments further confirmed that the SA-imprinted RNase A@BS-NPs had specific tumor-targeting ability and high therapeutic efficacy of RNase A in xenograft tumor model. Due to the specific targeting and traceless GSH-stimulated intracellular protein release, the SA-imprinted BS-NPs provided a promising platform for the delivery of biomacromolecules in cancer therapy.


Assuntos
Antineoplásicos , Nanopartículas , Neoplasias , Humanos , Ribonuclease Pancreático/metabolismo , Nanopartículas/uso terapêutico , Dióxido de Silício/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias/patologia , Oxirredução , Proteínas/metabolismo , Linhagem Celular Tumoral
20.
Mitochondrial DNA B Resour ; 6(4): 1554-1556, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33969216

RESUMO

We report the complete mitochondrial genome of Bottapotamon lingchuanense for the first time, which is found to be 17,612 base pairs in length, and contains 13 protein-coding genes (PCGs), 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA), and 1 non-coding AT-rich region known as the D-loop. In addition, the mitogenome has 17 intergenic regions ranging from 1 to 1512 bp in length. The mitochondrial genome of B. lingchuanense is the first mitochondrial genome under the genus Bottapotamon, providing DNA data for species identification, enriching the species diversity of Brachyura. The maximum-likelihood (ML) tree and Bayesian inference (BI) tree based on the 13 PCGs of mitochondrial genome of Brachyura species showed similar topologies with high confidence, and the analysis results were consistent with the current mainstream classification system. The results indicating that B. lingchuanense is closely related to Neilupotamon sinense, Sinopotamon, and Tenuilapotamon, and it is likely to be derived from them.

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