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1.
Biomacromolecules ; 25(2): 1047-1057, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38225889

RESUMO

Biodegradable guanidinium-functionalized polycarbonates kill cancer cells via membrane translocation without causing resistance after repeated use, but the exact molecular targets of the polycarbonates are unknown. Here, we investigate the protein targets of the polycarbonates through affinity-based protein profiling and report myeloid-derived growth factor (MYDGF) as the main protein target. Direct binding of the polycarbonates to MYDGF protein is validated through biolayer interferometry. MYDGF is overexpressed in a range of cancer cells, and knockdown of MYDGF is shown to reduce cell proliferation in cancer cells. Through morphological profiling, we also identify similarities in phenotypic effects of the functionalized polycarbonates with topoisomerase I inhibitors, MDM2 inhibitors, and phosphatidylinositol 3kinase inhibitors against cancer cells, suggesting a common mechanism through the PIK3/AKT pathway leading to apoptosis. These findings present the first macromolecular compound targeting MYDGF and may serve as an example for MYDGF modulation as a potential new target for macromolecular chemotherapeutic development.


Assuntos
Antineoplásicos , Proteômica , Substâncias Macromoleculares/farmacologia , Antineoplásicos/farmacologia , Proliferação de Células
2.
Nanomedicine ; 58: 102745, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38499167

RESUMO

Understanding the stability of mRNA loaded lipid nanoparticles (mRNA-LNPs) is imperative for their clinical development. Herein, we propose the use of size-exclusion chromatography coupled with dual-angle light scattering (SEC-MALS) as a new approach to assessing mRNA-LNP stability in pure human serum and plasma. By applying a dual-column configuration to attenuate interference from plasma components, SEC-MALS was able to elucidate the degradation kinetics and physical property changes of mRNA-LNPs, which have not been observed accurately by conventional dynamic light scattering techniques. Interestingly, both serum and plasma had significantly different impacts on the molecular weight and radius of gyration of mRNA-LNPs, suggesting the involvement of clotting factors in desorption of lipids from mRNA-LNPs. We also discovered that a trace impurity (~1 %) in ALC-0315, identified as its O-tert-butyloxycarbonyl-protected form, greatly diminished mRNA-LNP stability in serum. These results demonstrated the potential utility of SEC-MALS for optimization and quality control of LNP formulations.


Assuntos
Cromatografia em Gel , Lipídeos , Nanopartículas , RNA Mensageiro , Humanos , RNA Mensageiro/genética , RNA Mensageiro/sangue , Nanopartículas/química , Lipídeos/química , Difusão Dinâmica da Luz , Plasma/química , Luz , Espalhamento de Radiação , Soro/química , Estabilidade de RNA , Lipossomos
3.
Small ; 19(40): e2301748, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37282762

RESUMO

Extracellular vesicles (EVs) are lipid bilayer nanovesicles released from living or apoptotic cells that can transport DNA, RNA, protein, and lipid cargo. EVs play critical roles in cell-cell communication and tissue homeostasis, and have numerous therapeutic uses including serving as carriers for nanodrug delivery. There are multiple ways to load EVs with nanodrugs, such as electroporation, extrusion, and ultrasound. However, these approaches may have limited drug-loading rates, poor EV membrane stability, and high cost for large-scale production. Here, it is shown that apoptotic mesenchymal stem cells (MSCs) can encapsulate exogenously added nanoparticles into apoptotic vesicles (apoVs) with a high loading efficiency. When nano-bortezomib is incorporated into apoVs in culture-expanded apoptotic MSCs, nano-bortezomib-apoVs show a synergistic combination effect of bortezomib and apoVs to ameliorate multiple myeloma (MM) in a mouse model, along with significantly reduced side effects of nano-bortezomib. Moreover, it is shown that Rab7 regulates the nanoparticle encapsulation efficiency in apoptotic MSCs and that activation of Rab7 can increase nanoparticle-apoV production. In this study, a previously unknown mechanism to naturally synthesize nano-bortezomib-apoVs to improve MM therapy is revealed.


Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , Mieloma Múltiplo , Animais , Camundongos , Bortezomib/farmacologia , Bortezomib/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/metabolismo , Vesículas Extracelulares/metabolismo , Comunicação Celular
4.
Biomacromolecules ; 24(12): 5551-5562, 2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-37828909

RESUMO

Helicobacter pylori, the world's most common chronic infection-causing pathogen, is responsible for causing gastric ulcers, the fourth-leading cause of cancer-related death globally in 2020. In recent years, the effectiveness of the current treatment regimen (two antibiotics and one proton pump inhibitor) has often been plagued with problems such as resistance and the undesired elimination of commensal bacteria. Herein, we report the synthesis of block and random copolycarbonates, functionalized with cationic guanidinium and anionic acetate functional groups, aimed at selectively killing H. pylori in the acidic environment of the stomach, while remaining nontoxic to the commensal bacteria in the gut. The compositions of the polymers were fine-tuned so that the polymers were readily dispersed in water without any difficulty at both pH 3.0 and 7.4. The self-assembly behavior of the polymers at different pH values by dynamic light scattering showed that the random and block copolymers formed stable micelles in a simulated gastric environment (pH 3.0) while aggregated at pH 7.4. Both polymers demonstrated stronger antibacterial activity against H. pylori than the guanidinium-functionalized homopolymer without any acetate functional group at pH 3.0. The block copolymer was significantly more bactericidal at pH 3.0 across the concentrations tested, as compared to the random copolymer, while it did not show significant toxicity toward rat red blood cells (rRBCs) and HK-2 cells or bactericidal effect toward E. coli (a common gut bacterium) and nor caused aggregation of rRBCs at its effective concentration and at physiological pH of 7.4. Additionally, both the block and random copolymers were much more stable against hydrolysis at pH 3.0 than at pH 7.4. This study provides insight into the influence of both polymer architecture and dynamic assembly on the bioactivities of antimicrobial polymers, where the disassembly of coacervates into narrowly dispersed micelles at pH 3 make them potent antimicrobials aided by the protonated carboxylic acid block.


Assuntos
Helicobacter pylori , Micelas , Ratos , Animais , Guanidina/farmacologia , Escherichia coli , Polímeros/farmacologia , Polímeros/química , Antibacterianos/farmacologia , Concentração de Íons de Hidrogênio , Acetatos
5.
J Cell Mol Med ; 26(6): 1729-1741, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33560588

RESUMO

Renal cell carcinoma (RCC) is the most common form of kidney cancer, with a high recurrence rate and metastasis capacity. Circular RNAs (circRNAs) have been suggested to act as the critical regulator in several diseases. This study is designed to investigate the role of circCSNK1G3 on RCC progression. We observed a highly expression of circCSNK1G3 in RCC tissues compared with normal tissues. The aberrantly circCSNK1G3 promoted the tumour growth and metastasis in RCC. In the subsequent mechanism investigation, we discovered that the tumour-promoting effects of circCSNK1G3 were, at least partly, achieved by up-regulating miR-181b. Increased miR-181b inhibits several tumour suppressor gene, including CYLD, LATS2, NDRG2 and TIMP3. Furthermore, the decreased TIMP3 leads to the enhanced epithelial to mesenchymal transition (EMT) process, thus promoting the cancer metastasis. In conclusion, we identified the oncogenic role of circCSNK1G3 in RCC progression and demonstrated the regulatory role of circCSNK1G3 induced miR-181b expression, which leads to TIMP3-mediated EMT process, thus resulting in tumour growth and metastasis in RCC. This study reveals the promise of circCSNK1G3 to be developed as a potential diagnostic and prognostic biomarker in the clinic. And the roles of circCSNK1G3 in cancer research deserve further investigation.


Assuntos
Carcinoma de Células Renais , Caseína Quinase I/genética , Neoplasias Renais , MicroRNAs , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Renais/genética , Neoplasias Renais/patologia , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Serina-Treonina Quinases , Inibidor Tecidual de Metaloproteinase-3/genética , Inibidor Tecidual de Metaloproteinase-3/metabolismo , Proteínas Supressoras de Tumor/genética
6.
Nanomedicine ; 40: 102492, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34775062

RESUMO

Cancer immunotherapy has recently emerged as a rising star due to its ability to activate patients' immune systems to fight tumors and prevent relapse. Conversely, the interest in cancer nanomedicine has seemingly waned due to its lackluster clinical translation. Despite being hailed as a game-changer in oncology, cancer immunotherapy still faces numerous challenges. Combining both entities together has thus been one among several solutions proposed to circumvent these challenges. This solution has since gained traction and has also led to a renaissance of cancer nanomedicine. While most combinations are currently experimental at best, some have progressed on to clinical trials. This review thus seeks to examine the advantages and disadvantages of integrating both modalities as a cancer treatment. The opportunities, challenges and future directions of this emerging field will also be explored with the hope that such a combination will lead to a paradigm shift in cancer treatments.


Assuntos
Nanomedicina , Neoplasias , Humanos , Imunoterapia , Neoplasias/tratamento farmacológico
7.
Nanomedicine ; 45: 102591, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35907618

RESUMO

The efficacy of Adoptive Cell Therapy (ACT) for solid tumor is still mediocre. This is mainly because tumor cells can hijack ACT T cells' immune checkpoint pathways to exert immunosuppression in the tumor microenvironment. Immune Checkpoint Inhibitors such as anti-PD-1 (aPD1) can counter the immunosuppression, but the synergizing effects of aPD1 to ACT was still not satisfactory. Here we demonstrate an approach to safely anchor aPD1-formed nanogels onto T cell surface via bio-orthogonal click chemistry before adoptive transfer. The spatial-temporal co-existence of aPD1 with ACT T cells and the responsive drug release significantly improved the treatment outcome of ACT in murine solid tumor model. The average tumor weight of the group treated by cell-surface anchored aPD1 was only 18 % of the group treated by equivalent dose of free aPD1 and T cells. The technology can be broadly applicable in ACTs employing natural or Chimeric Antigen Receptor (CAR) T cells.


Assuntos
Neoplasias , Receptores de Antígenos Quiméricos , Animais , Terapia Baseada em Transplante de Células e Tecidos , Inibidores de Checkpoint Imunológico , Imunoterapia Adotiva , Camundongos , Nanogéis , Neoplasias/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Microambiente Tumoral
8.
Nanomedicine ; 35: 102398, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33901646

RESUMO

Bacterial membrane vesicles (MVs) are particles secreted by bacteria with diameter of 20-400 nm. The pathogen-associated molecular patterns (PAMPs) present on the surface of MVs are capable of activating human immune system, leading to non-specific immune response and specific immune response. Due to the immunostimulatory properties and proteoliposome nanostructures, MVs have been increasingly explored as vaccines or delivery systems for the prevention and treatment of bacterial infections. Herein, the recent progresses of MVs for antibacterial applications are reviewed to provide an overview of MVs vaccines and MVs-related delivery systems. In addition, the safety issues of bacterial MVs are discussed to demonstrate their potential for clinical translation. In the end of this review, the challenges of bacterial MVs as vaccines and delivery systems for clinical applications are highlighted with the purpose of predicting future research directions in this field.


Assuntos
Bactérias , Infecções Bacterianas , Proteínas de Bactérias , Vacinas Bacterianas , Membrana Celular , Nanoestruturas , Bactérias/química , Bactérias/imunologia , Infecções Bacterianas/imunologia , Infecções Bacterianas/prevenção & controle , Proteínas de Bactérias/química , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/uso terapêutico , Vacinas Bacterianas/química , Vacinas Bacterianas/imunologia , Vacinas Bacterianas/uso terapêutico , Membrana Celular/química , Membrana Celular/imunologia , Humanos , Lipossomos , Nanoestruturas/química , Nanoestruturas/uso terapêutico
9.
J Am Chem Soc ; 142(50): 21082-21090, 2020 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-33274928

RESUMO

Searching for membrane-active synthetic analogues that are structurally simple yet functionally comparable to natural channel proteins has been of central research interest in the past four decades, yet custom design of the ion transport selectivity still remains a grand challenge. Here we report on a suite of buckyball-based molecular balls (MBs), enabling transmembrane ion transport selectivity to be custom designable. The modularly tunable MBm-Cn (m = 4-7; n = 6-12) structures consist of a C60-fullerene core, flexible alkyl linkers Cn (i.e., C6 for n-C6H12 group), and peripherally aligned benzo-3m-crown-m ethers (i.e., m = 4 for benzo-12-crown-4) as ion-transporting units. Screening a matrix of 16 such MBs, combinatorially derived from four different crown units and four different Cn linkers, intriguingly revealed that their transport selectivity well resembles the intrinsic ion binding affinity of the respective benzo-crown units present, making custom design of the transport selectivity possible. Specifically, MB4s, containing benzo-12-crown-4 units, all are Li+-selective in transmembrane ion transport, with the most active MB4-C10 exhibiting an EC50(Li+) value of 0.13 µM (corresponding to 0.13 mol % of the lipid present) while excluding all other monovalent alkali-metal ions. Likewise, the most Na+ selective MB5-C8 and K+ selective MB6-C8 demonstrate high Na+/K+ and K+/Na+ selectivity values of 13.7 and 7.8, respectively. For selectivity to Rb+ and Cs+ ions, the most active MB7-C8 displays exceptionally high transport efficiencies, with an EC50(Rb+) value of 105 nM (0.11 mol %) and an EC50(Cs+) value of 77 nM (0.079 mol %).

10.
Mol Cancer ; 19(1): 102, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32503543

RESUMO

Extracellular vesicles (EVs), a class of heterogeneous membrane vesicles, are generally divided into exosomes and microvesicles on basis of their origination from the endosomal membrane or the plasma membrane, respectively. EV-mediated bidirectional communication among various cell types supports cancer cell growth and metastasis. EVs derived from different cell types and status have been shown to have distinct RNA profiles, comprising messenger RNAs and non-coding RNAs (ncRNAs). Recently, ncRNAs have attracted great interests in the field of EV-RNA research, and growing numbers of ncRNAs ranging from microRNAs to long ncRNAs have been investigated to reveal their specific functions and underlying mechanisms in the tumor microenvironment and premetastatic niches. Emerging evidence has indicated that EV-RNAs are essential functional cargoes in modulating hallmarks of cancers and in reciprocal crosstalk within tumor cells and between tumor and stromal cells over short and long distance, thereby regulating the initiation, development and progression of cancers. In this review, we discuss current findings regarding EV biogenesis, release and interaction with target cells as well as EV-RNA sorting, and highlight biological roles and molecular mechanisms of EV-ncRNAs in cancer biology.


Assuntos
Biomarcadores Tumorais/genética , Vesículas Extracelulares/genética , MicroRNAs/genética , Neoplasias/patologia , RNA Mensageiro/genética , RNA não Traduzido/genética , Microambiente Tumoral/imunologia , Animais , Progressão da Doença , Humanos , Metástase Neoplásica , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/metabolismo
11.
Nanomedicine ; 28: 102215, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32438106

RESUMO

Mesenchymal stem cells are promising medicine for treating diseases and tissue defects because of their innate ability to secrete therapeutic factors. Intravenous delivery of stem cells, although favored for its minimal invasiveness, is often plagued by low cellular engraftment in the target tissue. To this end, this study hypothesizes that in situ activation of cellular expression of CXC chemokine 4 (CXCR4) would significantly improve cellular migration to injured tissue. This hypothesis was examined by tethering the surface of stem cells with poly(D,L-lactide-co-glycolide)-block-hyaluronic acid (HA) particles containing stromal cell-derived factor-1α, a model chemokine to sensitize CXCR4. The HA blocks in the particles enhanced the association rate constant to stem cells by 3.3-fold, and in turn, increased the number of cells expressing CXCR4 receptors. Consequently, these cells displayed 1.2-fold higher transendothelial migration in vitro and 1.7-fold greater trafficking to the ischemic hindlimb of a mouse than that of the untethered cells.


Assuntos
Isquemia/metabolismo , Receptores CXCR4/metabolismo , Células-Tronco/citologia , Animais , Quimiocina CXCL12/metabolismo , Membro Posterior/metabolismo , Cinética , Espectroscopia de Ressonância Magnética , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Células-Tronco/metabolismo
12.
Biomacromolecules ; 20(7): 2737-2742, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-31117355

RESUMO

Polyionenes are a unique class of materials in which the charges reside along the polymer backbone and have emerged as an important class of antimicrobials. In this study, we have synthesized polyionenes based on quaternary ammonium salts consisting of amides or esters or amide/ester combinations. These materials have a broad spectrum of antimicrobial activity against various types of pathogenic microbes and exhibit a low minimum inhibitor concentration. Importantly, polyionenes with amides outperformed esters in terms of their antimicrobial activity, selectivity, and killing kinetics. Our findings offer insights into the macromolecular design to access selective and potent antimicrobial agents.


Assuntos
Amidas/farmacologia , Infecções Bacterianas/tratamento farmacológico , Ésteres/farmacologia , Polímeros/farmacologia , Anti-Infecciosos/farmacologia , Infecções Bacterianas/microbiologia , Humanos , Cinética , Testes de Sensibilidade Microbiana , Polímeros/química , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/farmacologia , Relação Estrutura-Atividade
13.
Nanomedicine ; 21: 102056, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31336176

RESUMO

Prolonged vaccine release enables gradual immunostimulation, providing long-term immunity. Herein, Vitamin E-PEG-Vitamin E triblock 'ABA' hydrogel, which is formed through physical cross-linking of flower-shaped micelles and can reside in vivo for >17 weeks, was employed for delivery of cancer preventive vaccines to provide sustained anticancer immunity. Mice vaccinated with hydrogel formulations produced a significantly higher quantity of antibodies compared to solution formulations. OVA was used to study EG.7-OVA tumor rejection in vaccinated mice. Among all formulations, OVA-loaded hydrogel containing aluminum-based adjuvant had the best therapeutic outcome, and only 2/10 mice developed solid tumors with significantly smaller tumor size. Moreover, no adverse effect on liver and kidney was detected with the hydrogel formulation. In a lymphoma metastasis mouse model, vaccination with the OVA-loaded hydrogel and adjuvant resulted in increased survival (66.7%) compared to other formulations (12.5-50%) over 100 days. This hydrogel is a promising formulation for sustained delivery of vaccines.


Assuntos
Vacinas Anticâncer/farmacologia , Portadores de Fármacos/farmacologia , Hidrogéis/farmacologia , Imunidade Celular/efeitos dos fármacos , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/farmacologia , Animais , Plásticos Biodegradáveis/química , Plásticos Biodegradáveis/farmacologia , Vacinas Anticâncer/imunologia , Portadores de Fármacos/química , Humanos , Hidrogéis/química , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Camundongos , Neoplasias/imunologia , Neoplasias/patologia , Neoplasias/terapia , Ovalbumina/efeitos dos fármacos , Ovalbumina/imunologia , Vitamina E/química , Vitamina E/farmacologia
14.
Nanomedicine ; 17: 236-245, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30738234

RESUMO

Apomorphine (AMP, used for treatment of Parkinson's disease) is susceptible to oxidation. Its oxidized products are toxic. To overcome these issues, AMP was conjugated to phenylboronic acid-functionalized polycarbonate through pH-sensitive covalent boronate ester bond between phenylboronic acid and catechol in AMP. Various conditions (use of base as catalyst, reaction time and initial drug loading) were optimized to achieve high AMP conjugation degree and mitigate polymer degradation caused by amine in AMP. Pyridine accelerated AMP conjugation and yielded ~74% conjugation within 5 min. Tertiary amine groups were incorporated to polycarbonate, and served as efficient catalyst (~80% conjugation within 5 min). AMP-conjugated polymer self-assembled into nanoparticles. AMP release from the nanoparticles was minimal at pH 7.4, while in acidic environment (endolysosomes) rapid release was observed. Encapsulation protected AMP from oxidization. The nanoparticles were significantly accumulated in the brain tissue after intranasal delivery. These AMP-loaded nanoparticles have potential use for treatment of Parkinson's disease.


Assuntos
Apomorfina/administração & dosagem , Agonistas de Dopamina/administração & dosagem , Portadores de Fármacos/química , Cimento de Policarboxilato/química , Animais , Apomorfina/farmacocinética , Barreira Hematoencefálica/metabolismo , Ácidos Borônicos/química , Agonistas de Dopamina/farmacocinética , Liberação Controlada de Fármacos , Feminino , Camundongos Endogâmicos BALB C , Nanopartículas/química
15.
J Am Chem Soc ; 140(12): 4244-4252, 2018 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-29504396

RESUMO

Drug resistance to chemotherapeutics is a recurrent issue plaguing many cancer treatment regimens. To circumvent resistance issues, we have designed a new class of macromolecules as self-contained chemotherapeutic agents. The macromolecular chemotherapeutic agents readily self-assemble into well-defined nanoparticles and show excellent activity in vitro against multiple cancer cell lines. These cationic polymers function by selectively binding and lysing cancer cell membranes. As a consequence of this mechanism, they exhibit significant potency against drug-resistant cancer cells and cancer stem cells, prevent cancer cell migration, and do not induce resistance onset following multiple treatment passages. Concurrent experiments with the small-molecule chemotherapeutic, doxorubicin, show aggressive resistance onset in cancer cells, a lack of efficacy against drug-resistant cancer cell lines, and a failure to prevent cancer cell migration. Additionally, the polymers showed anticancer efficacy in a hepatocellular carcinoma patient derived xenograft mouse model. Overall, these results demonstrate a new approach to designing anticancer therapeutics utilizing macromolecular compounds.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Neoplasias Hepáticas Experimentais/patologia , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/química , Substâncias Macromoleculares/farmacologia , Camundongos , Estrutura Molecular , Nanopartículas/química , Tamanho da Partícula , Relação Estrutura-Atividade
16.
Langmuir ; 34(38): 11242-11252, 2018 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-30173514

RESUMO

Hydrogen peroxide (H2O2) is an attractive chemical because of its bleaching properties in paper and pulp industry and as a disinfectant in the food, water, and medical industries. However, it is important to monitor the residual H2O2 level after its usage and prevent any unintended health problems or chemical reactions. Most H2O2 sensors often utilize fluorophores or electrical circuitry that requires an additional irradiation or a digital display. To this end, this study presents a 3,3',5,5'-tetramethylbenzidine (TMB)/horseradish peroxidase (HRP)-loaded patch that alerts the presence of high H2O2 levels by generating a visible blue color. We hypothesized that water-insoluble TMB immobilized within mesoporous silica particles of proper pore diameter and structure would act as a colorimetric indicator through the H2O2-mediated oxidation within a cross-linked patch. We examined this hypothesis by immobilizing TMB molecules in mesoporous silica particles with 2 and 7 nm diameter cylindrical pores as well as on nonporous silica particles. Then, we loaded these TMB-silica particles and HRP in a porous alginate patch via sequential in situ cross-linking reaction and lyophilization. In the presence of 25-5000 µM H2O2, which simulate H2O2 concentrations found in residual disinfecting fluids, the patch loaded with TMB-mesoporous silica particles with 7 nm diameter pores generated a distinct blue color with varying intensities depending on the H2O2 concentration. The design principles demonstrated in this study should be applicable to a broad array of sensors to be integrated into a moldable, three-dimensional matrix.


Assuntos
Benzidinas/química , Compostos Cromogênicos/química , Peróxido de Hidrogênio/análise , Dióxido de Silício/química , Adsorção , Alginatos/química , Armoracia/enzimologia , Colorimetria/métodos , Peroxidase do Rábano Silvestre/química , Cinética , Oxirredução , Porosidade , Dióxido de Silício/síntese química
17.
Future Oncol ; 14(27): 2875-2886, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30208739

RESUMO

miRNAs are a class of single-stranded noncoding RNAs, which have no coding potential, but modulate many molecular mechanisms including cancer pathogenesis. miRNAs participate in cell proliferation, differentiation, apoptosis, as well as carcinogenesis or cancer progression, and their involvement in lung cancer has been recently shown. They are suggested to have bidirectional functions on important cancer-related genes so as to enhance or attenuate tumor genesis. Epithelial-mesenchymal transition (EMT) is a fundamental process which contributes to integrity of organogenesis and tissue differentiation as well as tissue repair, organ fibrosis and the progression of carcinoma, and several miRNAs were suggested to form the network regulating EMT in lung cancer, among which, miR-200 family members (miR-200a, miR-200b, miR-200c, miR-429 and miR-141) play crucial roles in the suppression of EMT.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , MicroRNAs/metabolismo , Apoptose/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Diferenciação Celular/genética , Proliferação de Células/genética , Progressão da Doença , Epigênese Genética , Genes Supressores de Tumor , Humanos , Neoplasias Pulmonares/patologia , MicroRNAs/genética
18.
Nanomedicine ; 14(2): 405-414, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29175597

RESUMO

The presence of cancer stem cells (CSCs) is one of the main reasons that cause cancer relapse and metastasis. In this study, NF-κB shRNA was delivered to target CSCs using carbamate-mannose modified PEI (CMP) as a non-viral gene vector. The polymer was synthesized by blocking primary amine groups of branched PEI (10kDa) through nucleophilic addition between PEI and protected mannose-functionalized cyclic carbonate, followed by mannose deprotection. CMP/control shRNA nanocomplexes showed lower cytotoxicity and higher transfection efficiency in 4T1 murine breast cancer cells than unmodified PEI/control shRNA nanocomplexes. Importantly, CMP/NF-κB shRNA nanocomplexes (CMPN) were capable of inhibiting migration and invasion, decreasing mammosphere and colony formation and lowering ALDH+ CSC population. Furthermore, CMPN not only induced apoptosis and inhibited cell proliferation, but also sensitized the cells to the treatment with doxorubicin-loaded micellar nanoparticles. Therefore, CMPN may provide a promising approach for eliminating CSCs to prevent cancer relapse and metastasis.


Assuntos
Neoplasias da Mama/prevenção & controle , Doxorrubicina/farmacologia , NF-kappa B/antagonistas & inibidores , Nanopartículas/administração & dosagem , Células-Tronco Neoplásicas/efeitos dos fármacos , Polietilenoimina/química , RNA Interferente Pequeno/genética , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Carbamatos/química , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Manose/química , NF-kappa B/genética , Nanopartículas/química , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Polímeros/administração & dosagem , Polímeros/química , Células Tumorais Cultivadas
19.
Nanomedicine ; 14(1): 165-172, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28974393

RESUMO

Low molecular weight cationic compounds were synthesized from re-purposed poly(ethylene teraphthalate) (PET) and used to self-assemble into high aspect ratio supramolecular nanofibers for encapsulation and delivery of anionic antibiotics. The antibiotic piperacillin/tazobactam (PT) was successfully loaded into the nanofibers through ionic interaction between anionic PT and the cationic nanofibers without loss of the nanofiber features. These PT-loaded nanofibers demonstrated high loading efficiency and sustained delivery for PT. The antimicrobial activity of PT-loaded nanofibers remained potent towards both Gram-positive and Gram-negative bacteria. Importantly, in a P. aeruginosa-infected mouse skin wound model, the treatment with the PT-loaded nanofibers was more effective than free PT for wound healing as evidenced by the significantly lower P. aeruginosa counts at the wound sites and histological analysis. This strategy can be applied to deliver a variety of anionic antibiotics for improved treatment efficacy of various infections.


Assuntos
Antibacterianos/administração & dosagem , Cátions/química , Nanofibras/química , Polietilenotereftalatos/química , Infecções por Pseudomonas/tratamento farmacológico , Animais , Antibacterianos/química , Portadores de Fármacos , Reposicionamento de Medicamentos , Camundongos , Camundongos Endogâmicos C57BL , Infecções por Pseudomonas/microbiologia , Infecções por Pseudomonas/patologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/microbiologia , Pele/patologia , Cicatrização/efeitos dos fármacos
20.
Nanomedicine ; 14(8): 2666-2677, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30017961

RESUMO

Herein, we report reactive oxygen species (ROS)- and pH-responsive biodegradable polyethylene glycol (PEG)-block-polycarbonate by installing thioether groups onto the polycarbonate and its self-assembled core/shell structured micelles for anticancer drug delivery. Oxidation of thioethers to sulfoxide and subsequently sulfone induces an increase in hydrophilicity, resulting in more hydrophilic micellar core. This phase-change caused the micelles to swell and enhance cargo release. Carboxylic acid groups have also been installed onto thioether-containing polycarbonate to promote loading of amine-containing anticancer doxorubicin through electrostatic interaction. Urea-functionalized thioether-containing PEG-block-polycarbonates were synthesized to mix with the acid-functionalized PEG-block-polycarbonate for stabilizing micelle structure through hydrogen-bonding interaction. The mixed micelles were 50 nm in diameter and had a 25 wt% loading capacity for doxorubicin. Enhanced drug release from the micelles was triggered by low pH and high content of ROS. Drug-encapsulated micelles accumulated in tumors through leaky tumor vasculature in PC-3 human prostate cancer xenograft mouse model.


Assuntos
Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Nanopartículas/administração & dosagem , Polímeros/química , Neoplasias da Próstata/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/farmacologia , Apoptose , Proliferação de Células , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Portadores de Fármacos , Humanos , Concentração de Íons de Hidrogênio , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Micelas , Nanopartículas/química , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
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