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1.
J Am Chem Soc ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858162

RESUMO

Understanding how life's essential homochiral biopolymers arose from racemic precursors is a challenging quest. Herein, we present a groundbreaking approach involving hierarchical chiral assembly-driven stereoselective ring-opening polymerization of ε-benzyloxycarbonyl-l/d-lysine N-carboxyanhydrides assisted by ultrasonication in an aqueous medium. This method enabled a narrow dispersity within a few minutes and the achievement of high molecular weight for polypeptides, employing a living polymerization mechanism. The polymerization of l and d enantiomers yielded predominantly right- and left-handed superhelical assemblies in a one-pot preparation, respectively. Notably, stereoselective polypeptide segments were efficiently prepared through hierarchical assembly-driven polymerization of racemic monomers in the absence of a catalyst. This research offers an innovative strategy for the convenient preparations of stereoenriched polypeptides and, more importantly, sheds light on the plausible emergence of homochiral peptides in the origin of life.

2.
Small ; 20(23): e2309894, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38308168

RESUMO

Real-time biodistribution monitoring and enhancing the therapeutic efficacy of platinum(II)-based anticancer drugs are urgently required to elevate their clinical performance. Herein, a tetraphenylethene derivative (TP) with aggregation-induced emission (AIE) properties and an iodine atom are selected as ligands to endow platinum (II) complex TP-Pt-I with real-time in vivo self-tracking ability by fluorescence (FL) and computerized tomography (CT) imaging, and improved anticancer efficacy by the combination of chemotherapy and photodynamic therapy. Especially, benefiting from the formation of a donor-acceptor-donor structure between the AIE photosensitizer TP and Pt-I moiety, the heavy atom effects of Pt and I, and the presence of I, TP-Pt-I displayed red-shifted absorption and emission wavelengths, enhanced ROS generation efficiency, and improved CT imaging capacity compared with the pristine TP and the control agent TP-Pt-Cl. As a result, the enhanced intratumoral accumulation of TP-Pt-I loaded nanoparticles is readily revealed by dual-modal FL and CT imaging with high contrast. Meanwhile, the TP-Pt-I nanoparticles show significantly improved tumor growth-inhibiting effects on an MCF-7 xenograft murine model by combining the chemotherapeutic effects of platinum(II) and the photodynamic effects of TP. This self-tracking therapeutic complex thus provides a new strategy for improving the therapeutic outcomes of platinum(II)-based anticancer drugs.


Assuntos
Iodo , Fotoquimioterapia , Platina , Fotoquimioterapia/métodos , Humanos , Animais , Iodo/química , Platina/química , Platina/farmacologia , Linhagem Celular Tumoral , Tomografia Computadorizada por Raios X , Camundongos , Camundongos Nus , Nanopartículas/química , Etilenos/química , Etilenos/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Estilbenos
3.
Chemistry ; 30(2): e202302884, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37814820

RESUMO

The sustainable solution to the environmental problem of polymeric materials calls for efficient and well-controlled ring-opening polymerization catalytic systems. Inspired by the highly reactive and stereospecific bimetallic catalysts, three kinds of bimetallic Salen-Mn catalysts supported by biaryl linking moieties are synthesized and applied to polymerization catalysis of lactide (LA) and ϵ-caprolactone (ϵ-CL) in this work. The polymerization is initiated in situ by the ring-opening of epoxide compounds, in which the ionic cocatalyst could accelerate the reaction process. The Mn-Mn coordination effect contributes to the higher activity and iso-selectivity towards LA compared to the mononuclear Salen-Mn catalyst. The reactivity and stereoselectivity are determined by the conformation of catalysts, specifically the Mn-Mn separation and dihedral angle. Finally, the CO2 -controlled switchable polymerizations are carried out with LA and ϵ-CL. The reversibility of the on-off switching operation is influenced by the combination between CO2 molecules and active species. The success in binuclear Salen-Mn catalysts not only expands the range of bimetallic catalyst analogues but also claims the promising potential of Mn-based catalysts in practical and theoretical research.

4.
Biomacromolecules ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38843459

RESUMO

Messenger ribonucleic acid (mRNA) vaccines, serving as a rapid and easily scalable emergency preventive measure, have played a pivotal role in preventing infectious diseases. The effectiveness of mRNA vaccines heavily relies on the delivery carrier, but the current market options are predominantly lipid nanoparticles. Their intricate preparation process and high transportation costs pose challenges for widespread use in remote areas. In this study, we harnessed FDA-approved polymer PLGA and lipid components widely employed in clinical experiments to craft a ready-to-use mRNA vaccine delivery system known as lipid-polymer hybrid nanoparticles (LPP). Following formulation optimization, the PDCD nanoparticles emerged as the most effective, showcasing exceptional mRNA delivery capabilities both in vitro and in vivo. Loading PDCD nanoparticles with mRNA encoding the H1N1 influenza virus HA antigen-fused M2e peptide enabled the successful induction of M2e-specific antibodies and T cell immune responses in immunized mice. After three rounds of vaccine immunization, the mice demonstrated weight recovery to normal levels and maintained a survival rate exceeding 80% following an encounter with the H1N1 influenza virus. The innovative mRNA delivery system that we designed demonstrates outstanding effectiveness in preventing infectious diseases, with the potential to play an even more significant role in future clinical applications.

5.
Nano Lett ; 23(12): 5713-5721, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37313864

RESUMO

We report a simplistic approach that employs complexation between poly(N-allylglycine) modified with 3-mercaptoacetic acid (PNAG-COOH) and a series of metal ions to construct a new type of supramolecular architecture with intriguing features that enable a versatile and advanced nanoplatform. In most cases, such complexation results in nanoscale vesicles with superior stability, which differs significantly from the precipitates of conventional carbon-chain polymers and polypeptides. We attribute this to the polar tertiary amide groups in the polypeptoid backbone that offer excellent water affinity and numerous noncovalent molecular interactions. Particularly, the PNAG-COOH/Fe2+ complex can generate reactive oxygen species via a Fenton reaction in the presence of H2O2, thus causing ferroptosis selectively in the tumor cell. In addition, a H2O2-modulated intracellular in situ morphology transition enables prompt release of doxorubicin, representing a synergistic target antitumor efficacy. The prepared supramolecular platforms present promising candidates for many applications, considering the ability to assemble with various metal ions.


Assuntos
Ferroptose , Neoplasias , Humanos , Liberação Controlada de Fármacos , Microambiente Tumoral , Peróxido de Hidrogênio , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Doxorrubicina/química , Metais , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico
6.
Nano Lett ; 23(10): 4191-4200, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37186944

RESUMO

Multispecific antibodies (MsAbs) maintain the specificity of versatile antibodies while simultaneously addressing different epitopes for a cumulative, collaborative effect. They could be an alternative treatment to chimeric antigen receptor-T cell therapy by helping to redirect T cells to tumors in vivo. However, one major limitation of their development is their relatively complex production process, which involves performance of a massive screen with low yield, inconsistent quality, and nonnegligible impurities. Here, a poly(l-glutamic acid)-conjugated multiple Fc binding peptide-based synthesis nanoplatform was proposed, in which MsAbs were constructed by mixing the desired monoclonal antibodies (mAbs) with polymeric Fc binding peptides in aqueous solution without purification. To determine its efficacy, a dual immune checkpoint-based PD1/OX40 bispecific antibody and PDL1/CD3e/4-1BB trispecific antibody-based T cell engager were generated to trigger antitumor CD8+ T responses in mice, showing superior tumor suppression over free mixed mAbs. In this study, a facile, versatile build platform for MsAbs was established.


Assuntos
Anticorpos Biespecíficos , Neoplasias , Animais , Camundongos , Neoplasias/terapia , Anticorpos Monoclonais , Linfócitos T , Imunoterapia Adotiva
7.
Nano Lett ; 23(9): 3678-3686, 2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37052638

RESUMO

Identification of cancer metastatic sites is of importance for adjusting therapeutic interventions and treatment choice. However, identifying the location of metastatic lesions with easy accessibility and high safety is challenging. Here we demonstrate that cancer metastatic sites can be accurately detected by a triple targeting nanoprobe. Through coencapsulating molecular beacons probing a cancer biomarker (CXCR4 mRNA), a lung metastatic biomarker (CTSC mRNA), and a bone metastatic biomarker (JAG1 mRNA), the nanoprobe decorated by SYL3C conjugated hyaluronic acid and ICAM-1 specific aptamer conjugated hyaluronic acid can target diverse phenotyped circulating tumor cells (CTCs) during epithelial-mesenchymal and mesenchymal-epithelial transitions in whole blood for sensitive probing. The detection of CTCs from cancer patients shows that the nanoprobe can provide accurate information to distinguish different cancer metastasis statuses including nonmetastasis, lung metastasis, and bone metastasis. This study proposes an efficient screening tool for identifying the location of distant metastatic lesions via facile blood biopsy.


Assuntos
Células Neoplásicas Circulantes , Humanos , Ácido Hialurônico , Biomarcadores Tumorais/genética , Biópsia , RNA Mensageiro/genética , Metástase Neoplásica
8.
Small ; 19(3): e2204039, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36412076

RESUMO

Self-assembled cationic polymeric nanostructures have been receiving increasing attention for efficient antibacterial agents. In this work, a new type of antibacterial agents is developed by preparing pH-dependent nanostructured assemblies from cationic copolypeptoid poly(N-allylglycine)-b-poly(N-octylglycine) (PNAG-b-PNOG) modified with cysteamine hydrochloride ((PNAG-g-NH2 )-b-PNOG) driven by crystallization and hydrophobicity of the PNOG blocks. Due to the presence of confined domains arising from crystalline PNOG, persistent spheres and fiber-like assemblies are obtained from the same polymer upon a heating-cooling cycle. This allows for direct comparison of antimicrobial efficiency of nanostructured assemblies with various morphologies that are otherwise similar. Both nanostructured assemblies exhibit extremely low toxicity to human red blood cells, irrespective of the presence of the hydrophobic block. Enhanced antimicrobial performance of the fiber-like micelles compared to the spheres, which result in high selectivity of the fibers, is shown. Notably, the fiber-like micelles show great efficacy in inhibition of the Staphylococcus aureus (S. aureus) biofilm formations and eradication of the mature biofilms, superior to vancomycin. The micelles also show potent in vivo antimicrobial efficacy in a S. aureus infection mouse skin model. With a systematic study, it is demonstrated that both micelles kill the bacteria through a membrane disruption mechanism. These results imply great potential of polypeptoid assemblies as promising excellent candidates for antibacterial treatment and open up new possibilities for the preparation of a new generation of nanostructured antimicrobials.


Assuntos
Anti-Infecciosos , Nanoestruturas , Infecções Estafilocócicas , Camundongos , Animais , Humanos , Staphylococcus aureus , Micelas , Antibacterianos/farmacologia , Antibacterianos/química , Nanoestruturas/química , Polímeros/química , Infecções Estafilocócicas/tratamento farmacológico , Modelos Animais de Doenças , Biofilmes , Testes de Sensibilidade Microbiana
9.
Langmuir ; 39(38): 13534-13545, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37712535

RESUMO

Poly(l-lactic acid) (PLLA) has been extensively utilized as a biomaterial for various biomedical applications. The first and one of the most critical steps upon contact with biological fluids is the adsorption of proteins on the material's surface. Understanding the behavior of protein adsorption is vital for guiding the synthesis and preparation of PLLA for biomedical purposes. In this study, total internal reflection fluorescence microscopy was employed to investigate the adsorption of human serum albumin (HSA) on PLLA films with different molar masses. We found that molar mass affects HSA adsorption in such a way that it affects only the adsorption rate constants, but not the desorption rate constants. Additionally, we observed that HSA adsorption is spatially heterogeneous and exhibits many strong binding sites regardless of the molar mass of the PLLA films. We found that the free volume of PLLA plays a crucial role in determining its water uptake capacity and surface hydration, consequently impacting the adsorption of HSA.


Assuntos
Poliésteres , Albumina Sérica Humana , Humanos , Adsorção , Peso Molecular
10.
Biomacromolecules ; 24(9): 4316-4327, 2023 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-37611178

RESUMO

Sulfur dioxide (SO2) based gas therapy has emerged as a novel anticancer therapeutic strategy because of its high therapeutic efficacy and biosafety. To precisely adjust the SO2 content and control gas release, herein, a thiol-responsive polypeptide SO2 prodrug mPEG-block-poly(2-amino-6-(2,4-dinitrophenylsulfonamido)hexanoic acid) (PEG-b-PLys-DNs) was designed and facilely synthesized by polymerization of a novel N-carboxyanhydride SO2-NCA. The anticancer potential of the self-assembled nanoparticles (SO2-NPs) was investigated in detail. First, PEG-b-PLys-DNs were synthesized by ring-opening polymerization of SO2-NCA, which self-assembled into NPs sized 88.4 nm in aqueous. Subsequently, SO2-NPs were endocytosed into 4T1 cells and quickly released SO2 under a high concentration of glutathione in tumor cells. This process depleted cellular glutathione, generated reactive oxygen species, and dramatically increased oxidative stress, which led to cancer cell apoptosis. Finally, the in vivo anticancer efficacy of SO2-NPs was verified in 4T1-tumor-bearing mice. Our results indicated that this novel SO2 polymeric prodrug has great potential in eradicating tumors.


Assuntos
Nanopartículas , Neoplasias , Pró-Fármacos , Animais , Camundongos , Pró-Fármacos/farmacologia , Dióxido de Enxofre , Peptídeos/farmacologia , Glutationa , Neoplasias/tratamento farmacológico
11.
Macromol Rapid Commun ; 44(11): e2200929, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36840703

RESUMO

Increasing infiltration of CD8+ T cells can enhance the response rate to immune checkpoint blockade (ICB) therapies. In contrast, immunogenic cell death (ICD) induced by intracellular reactive oxygen species (ROS) is an effective strategy to increase CD8+ T cell infiltration. Cuproptosis is newly defined and reported by Tsvetkov et al. A Cu-coordinated covalent organic framework (COF) in which two valence states of copper ions are simultaneously loaded is prepared. On the one hand, Cu2+ undergoes a valence shift generating Cu+ which acts as an effective Fenton-like reagent to catalyze the production of · OH and 1 O2 from cellular overexpressed H2 O2 , causing DNA damage and lipid peroxidation (LPO), which directly produce cytotoxicity. On the other hand, residual Cu2+ can effectively deplete endogenous cellular glutathione (GSH), converting it into glutathione disulfide (GSSG), further increasing intracellular oxidative stress and reducing the scavenging of ROS, thus further enhancing the Fenton-like effect and bringing toxic effects on tumor cells. The synergy of these two functions achieves ICD, helping for transforming "cold tumor" into "hot tumor" and efficient anti-tumor effects eventually. This work provides new insights into coordinated COF and inspire the development of more versatile COF for biomedical applications.


Assuntos
Estruturas Metalorgânicas , Neoplasias , Humanos , Espécies Reativas de Oxigênio/metabolismo , Cobre , Morte Celular Imunogênica , Linfócitos T CD8-Positivos , Neoplasias/tratamento farmacológico , Glutationa , Peróxido de Hidrogênio/metabolismo , Linhagem Celular Tumoral
12.
Proc Natl Acad Sci U S A ; 117(50): 31639-31647, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33262279

RESUMO

Hierarchical nanomaterials have received increasing interest for many applications. Here, we report a facile programmable strategy based on an embedded segmental crystallinity design to prepare unprecedented supramolecular planar nanobrush-like structures composed of two distinct molecular packing motifs, by the self-assembly of one particular diblock copolymer poly(ethylene glycol)-block-poly(N-octylglycine) in a one-pot preparation. We demonstrate that the superstructures result from the temperature-controlled hierarchical self-assembly of preformed spherical micelles by optimizing the crystallization-solvophobicity balance. Particularly remarkable is that these micelles first assemble into linear arrays at elevated temperatures, which, upon cooling, subsequently template further lateral, crystallization-driven assembly in a living manner. Addition of the diblock copolymer chains to the growing nanostructure occurs via a loosely organized micellar intermediate state, which undergoes an unfolding transition to the final crystalline state in the nanobrush. This assembly mechanism is distinct from previous crystallization-driven approaches which occur via unimer addition, and is more akin to protein crystallization. Interestingly, nanobrush formation is conserved over a variety of preparation pathways. The precise control ability over the superstructure, combined with the excellent biocompatibility of polypeptoids, offers great potential for nanomaterials inaccessible previously for a broad range of advanced applications.

13.
Chin J Physiol ; 66(4): 228-238, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37635482

RESUMO

Mitochondrial dysfunction is closely intertwined with the progression of heart failure (HF). Ring-finger protein 5 (RNF5) is an E3 ubiquitin ligase, whose deletion induces the enhanced S100A8 expression. S100A8 regulates the mitochondrial dysfunction and S100A8/myeloid differentiation factor 88 (MYD88)/nuclear factor-kappa B (NF-κB) pathway promotes an inflammatory response; however, whether RNF5 modulated mitochondrial dysregulation and inflammation through the S100A8/MYD88/NF-κB axis remains unknown. Here, H9c2 cells were stimulated with oxygen-glucose deprivation/reperfusion (OGD/R) to build a HF model in vitro. RNF5 level was assessed in gene expression omnibus database and in OGD/R-induced H9c2 cells with reverse transcriptase quantitative polymerase chain reaction and western blot. The RNF5 level was overexpressed via transfecting RNF5 overexpression plasmids into H9c2 cells. The role and mechanism of RNF5 in OGD/R-elicited H9c2 cells were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide, spectrophotometry, flow cytometry, mitochondrial membrane potential (MMP) measurement, enzyme-linked immunosorbent assay and western blot assays. The RNF5 expression was downregulated both in silico and in OGD/R-stimulated H9c2 cells. OGD/R treatment caused a decrease in the cell viability, the MMP level, and the translational expression of mito-cyt-c and NF-κB-cyto, and an elevation in the concentrations of lactate dehydrogenase and creatine kinase myocardial band, the apoptosis rate, the inflammatory factor release, and the relative protein expression of cyto-cyt-c, S100A8, MYD88 and NF-κB-nuc in H9c2 cells. Upregulation of RNF5 reversed these indicators in OGD/R-stimulated H9c2 cells. Altogether, based on these outcomes, we concluded that RNF5 impeded mitochondrial dysfunction and inflammation through attenuating the S100A8/MYD88/NF-κB axis in OGD/R-stimulated H9c2 cells.


Assuntos
NF-kappa B , Oxigênio , Humanos , NF-kappa B/metabolismo , Oxigênio/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Transdução de Sinais , Miócitos Cardíacos/metabolismo , Glucose/metabolismo , Apoptose , Reperfusão , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Mitocôndrias , Inflamação
14.
Nano Lett ; 22(8): 3328-3339, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35404605

RESUMO

Nanomedicines are highly promising for cancer therapy due to their minimal side effects. However, little is known regarding their host immune response, which may limit their clinical efficacy and applications. Here, we find that cisplatin (CDDP)-loaded poly(l-glutamic acid)-graft-methoxy poly(ethylene glycol) complex nanoparticles (CDDP-NPs) elicit a strong antitumor CD8+ T cell-mediated immune response in a tumor-bearing mouse model compared to free CDDP. Mechanistically, the sustained retention of CDDP-NPs results in persistent tumor MHC-I overexpression, which promotes the formation of MHC-I-antigen peptide complex (pMHC-I), enhances the interaction between pMHC-I and T cell receptor (TCR), and leads to the activation of TCR signaling pathway and CD8+ T cell-mediated immune response. Furthermore, CDDP-NPs upregulate the costimulatory OX40 on intratumoral CD8+ T cells, and synergize with the agonistic OX40 antibody (aOX40) to suppress tumor growth by 89.2%. Our study provides a basis for the efficacy advantage of CDDP-based nanomedicines and immunotherapy.


Assuntos
Cisplatino , Nanopartículas , Animais , Apresentação de Antígeno , Linfócitos T CD8-Positivos , Linhagem Celular Tumoral , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Camundongos , Receptores de Antígenos de Linfócitos T
15.
Nano Lett ; 22(17): 7220-7229, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-35994713

RESUMO

The immune checkpoint blockade (ICB) faces a low response rate in clinical cancer treatment. Chemotherapy could enhance the response rate of the ICB, but patients would suffer from side effects. The off-target toxicity could be reduced by loading the chemotherapeutic agent through nanocarriers. Therefore, we developed a polymeric carrier for doxorubicin (DOX) loading to form DOX nanoparticles (DOX NPs), which were spatiotemporally responsive to the tumor microenvironment (TME). DOX NPs had an efficient transcytosis property for deep tumor infiltration and sustained drug release ability. Unfortunately, a binary therapy of DOX NPs and ICB induces tumor adaptive resistance and causes dynamic deterioration of the TME. We propose for the first time that TGF-ß1 is a major cause of tumor adaptive resistance and developed an immune cocktail therapy containing DOX NPs, ICB, and TGF-ß1 gene silencing nanoparticles. This therapy successfully overcame tumor adaptive resistance by reversing the immunosuppressive TME and achieved enhanced tumor treatment efficiency.


Assuntos
Nanopartículas , Neoplasias , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Portadores de Fármacos/farmacologia , Humanos , Imunoterapia , Nanopartículas/uso terapêutico , Transcitose , Fator de Crescimento Transformador beta1 , Microambiente Tumoral
16.
Angew Chem Int Ed Engl ; 62(35): e202305186, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37157011

RESUMO

Ultra-low molecular weight (ULMW) CO2 -polyols with well-defined hydroxyl end groups represent useful soft segments for the preparation of high-performance polyurethane foams. However, owing to the poor proton tolerance of catalysts towards CO2 /epoxide telomerization, it remains challenging to synthesize ULMW yet colorless CO2 -polyols. Herein, we propose an immobilization strategy of constructing supported catalysts by chemical anchoring of aluminum porphyrin on Merrifield resin. The resulting supported catalyst displays both extremely high proton tolerance (≈8000 times the equivalents of metal centers) and independence of cocatalyst, affording CO2 -polyols with ULMW (580 g mol-1 ) and high polymer selectivity (>99 %). Moreover, the ULMW CO2 -polyols with various architectures (tri-, quadra-, and hexa-arm) can be obtained, suggesting the wide proton universality of supported catalysts. Notably, benefiting from the heterogeneous nature of the supported catalyst, colorless products can be facilely achieved by simple filtration. The present strategy provides a platform for the synthesis of colorless ULMW polyols derived from not only CO2 /epoxides, but also lactone, anhydrides etc. or their combinations.

17.
Biomacromolecules ; 23(7): 2867-2877, 2022 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-35678301

RESUMO

The relatively low transfection efficiency limits further application of polymeric gene carriers. It is imperative to exploit a universal and simple strategy to enhance the gene transfection efficiency of polymeric gene carriers. Herein, we prepared a cationic polypeptide poly(γ-aminoethylthiopropyl-l-glutamate) (PALG-MEA, termed PM) with a stable α-helical conformation, which can significantly improve the gene transfection efficiency of cationic polymers. PM can be integrated into polymeric gene delivery systems noncovalently through electrostatic interactions. With the assistance of PM, polymeric gene delivery systems exhibited excellent cellular uptake and endosomal escape, thereby enhancing transfection efficiency. The transfection enhancement effect of PM was applicable to a variety of cationic polymers such as polyethylenimine (PEI), poly-l-lysine (PLL), and polyamidoamine (PAMAM). The ternary gene delivery system PM/pshVEGF/PEI exhibited an excellent antitumor effect against the B16F10 tumor model. Moreover, we demonstrated that PM could also enhance the delivery of gene editing systems (sgRNA-Cas9 plasmids). This work provides a facile and effective strategy for constructing polymeric gene delivery systems with a high transfection efficiency.


Assuntos
Técnicas de Transferência de Genes , Polietilenoimina , Cátions/química , Peptídeos/genética , Plasmídeos/genética , Polietilenoimina/química , Polímeros/química , Transfecção
18.
Nano Lett ; 21(5): 2088-2093, 2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33596078

RESUMO

Immunogenic cell death (ICD), a manner of tumor cell death that can trigger antitumor immune responses, has received extensive attention as a potential synergistic modality for cancer immunotherapy. Although many calcium ion (Ca2+) nanomodulators have been developed for cancer therapy through mitochondrial Ca2+ overload, their ICD-inducing properties have not been explored. Herein, an acid-sensitive PEG-decorated calcium carbonate (CaCO3) nanoparticle incorporating curcumin (CUR; a Ca2+ enhancer) (PEGCaCUR) was prepared using a simple one-pot strategy. PEGCaCUR served as not only a Ca2+ nanomodulator inducing efficient mitochondrial Ca2+ overload but also an ICD inducer during improved synergistic cancer therapy. Combination of PEGCaCUR with ultrasound (US), PEGCaCUR+US, led to an enhanced ICD effect attributable to the enhanced mitochondrial Ca2+ overload, along with subsequent upregulation of reactive oxygen species levels. PEGCaCUR also facilitates photoacoustic/fluorescence dual-mode imaging, as well as effectively suppressing tumor growth and metastasis, indicating promising theranostic properties.


Assuntos
Antineoplásicos , Nanopartículas , Cálcio , Morte Celular Imunogênica , Mitocôndrias
19.
Nano Lett ; 21(9): 3721-3730, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33891423

RESUMO

Chemo-immunotherapy combination effect remains to be a great challenge due to the poor tumor penetration of therapeutic agents that resulted from condensed extracellular matrix (ECM), T cell-related immune escape, and thus the potential recurrence. Herein, a helix self-assembly camptothecin (CPT) prodrug with simultaneous physical and physiological tumor penetration was constructed to realize effective chemo-immunotherapy. Specifically, CPT was modified with arginine to self-assemble into nanofibers to physically improve tumor penetration. Two plasmids, pshPD-L1 and pSpam1 for expressing small hairpin RNA PD-L1 and hyaluronidase, respectively, were loaded to down-regulate tumor surface PD-L1 expression for converting anergic state of T cells into the tumor-reactive T cells and produce hyaluronidase to physiologically degrade ECM for further enhanced tumor penetration. Moreover, the degraded ECM could also increase immune cells' infiltration into tumor sites, which may exert a synergistic antitumor immunity combined with immune checkpoint inhibition. Such a nanomedicine could cause significant inhibition of primary, distant tumors, and effective prevention of tumor recurrence.


Assuntos
Nanopartículas , Neoplasias , Pró-Fármacos , Linhagem Celular Tumoral , Humanos , Imunoterapia , Nanomedicina , Neoplasias/tratamento farmacológico , Pró-Fármacos/uso terapêutico
20.
Nano Lett ; 21(16): 6781-6791, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34382807

RESUMO

Gut bacteria and their metabolites influence the immune microenvironment of liver through the gut-liver axis, thus representing emerging therapeutic targets for liver cancer therapy. However, directly manipulating gut microbiota or their metabolites is not practical in clinic since the safety concerns and the complicated mechanism of action. Considering the dysregulated bile acid profiles associated with liver cancer, here we propose a strategy that directly manipulates the primary and secondary bile acid receptors through nanoapproach as an alternative and more precise way for liver cancer therapy. We show that nanodelivery of bile acid receptor modulators elicited robust antitumor immune responses and significantly changed the immune microenvironment in the murine hepatic tumor. In addition, ex vivo stimulation on both murine and patient hepatic tumor tissues suggests the observation here may be meaningful for clinical practice. This study elucidates a novel and precise strategy for liver cancer immunotherapy.


Assuntos
Microbioma Gastrointestinal , Neoplasias Hepáticas , Animais , Ácidos e Sais Biliares , Humanos , Imunoterapia , Neoplasias Hepáticas/tratamento farmacológico , Camundongos , Microambiente Tumoral
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