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1.
ACS Appl Mater Interfaces ; 16(11): 13543-13562, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38452225

RESUMEN

We use low-molecular-weight branched polyethylenimine (PEI) to produce cytocompatible reduced graphene oxide quantum dots (rGOQD) as a photothermal agent and covalently bind it with the photosensitizer IR-820. The rGOQD/IR820 shows high photothermal conversion efficiency and produces reactive oxygen species (ROS) after irradiation with near-infrared (NIR) light for photothermal/photodynamic therapy (PTT/PDT). To improve suspension stability, rGOQD/IR820 was PEGylated by anchoring with the DSPE hydrophobic tails in DSPE-PEG-Mal, leaving the maleimide (Mal) end group for covalent binding with manganese dioxide/bovine serum albumin (MnO2/BSA) and targeting ligand cell-penetrating peptide (CPP) to synthesize rGOQD/IR820/MnO2/CPP. As MnO2 can react with intracellular hydrogen peroxide to produce oxygen for alleviating the hypoxia condition in the acidic tumor microenvironment, the efficacy of PDT could be enhanced by generating more cytotoxic ROS with NIR light. Furthermore, quercetin (Q) was loaded to rGOQD through π-π interaction, which can be released in the endosomes and act as an inhibitor of heat shock protein 70 (HSP70). This sensitizes tumor cells to thermal stress and increases the efficacy of mild-temperature PTT with NIR irradiation. By simultaneously incorporating the HSP70 inhibitor (Q) and the in situ hypoxia alleviating agent (MnO2), the rGOQD/IR820/MnO2/Q/CPP can overcome the limitation of PTT/PDT and enhance the efficacy of targeted phototherapy in vitro. From in vivo study with an orthotopic brain tumor model, rGOQD/IR820/MnO2/Q/CPP administered through tail vein injection can cross the blood-brain barrier and accumulate in the intracranial tumor, after which NIR laser light irradiation can shrink the tumor and prolong the survival times of animals by simultaneously enhancing the efficacy of PTT/PDT to treat glioblastoma.


Asunto(s)
Antineoplásicos , Glioblastoma , Grafito , Fotoquimioterapia , Puntos Cuánticos , Animales , Compuestos de Manganeso/farmacología , Compuestos de Manganeso/química , Glioblastoma/tratamiento farmacológico , Puntos Cuánticos/uso terapéutico , Proteínas de Choque Térmico , Especies Reactivas de Oxígeno , Hipoxia Tumoral , Óxidos/farmacología , Óxidos/química , Fototerapia , Hipoxia , Línea Celular Tumoral , Microambiente Tumoral
2.
Mater Sci Eng C Mater Biol Appl ; 128: 112311, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34474862

RESUMEN

Herein, we design a rGO-based magnetic nanocomposite by decorating rGO with citrate-coated magnetic nanoparticles (CMNP). The magnetic rGO (mrGO) was modified by phospholipid-polyethylene glycol to prepare PEGylated mrGO, for conjugating with gastrin-releasing peptide receptor (GRPR)-binding peptide (mrGOG). The anticancer drug doxorubicin (DOX) was bound to mrGO (mrGOG) by π-π stacking for drug delivery triggered by the low pH value in the endosome. The mrGOG showed enhanced photothermal effect under NIR irradiation, endorsing its role for dual targeted DOX delivery. With efficient DOX release in the endosomal environment and heat generation from light absorption in the NIR range, mrGOG/DOX could be used for combination chemo-photothermal therapy after intracellular uptake by cancer cells. We characterized the physico-chemical as well as biological properties of the synthesized nanocomposites. The mrGOG is stable in biological buffer solution, showing high biocompatibility and minimum hemolytic properties. Using U87 glioblastoma cells, we confirmed the magnetic drug targeting effect in vitro for selective cancer cell killing. The peptide ligand-mediated targeted delivery increases the efficiency of intracellular uptake of both nanocomposite and DOX up to ~3 times due to the over-expressed GRPR on U87 surface, leading to higher cytotoxicity. The increased cytotoxicity using mrGOG over mrGO was shown from a decreased IC50 value (0.70 to 0.48 µg/mL) and an increased cell apoptosis rate (19.8% to 47.1%). The IC50 and apoptosis rate changed further to 0.19 µg/mL and 76.8% in combination with NIR laser irradiation, with the photothermal effect supported from upregulation of heat shock protein HSP70 expression. Using U87 tumor xenograft model created in nude mice, we demonstrated that magnetic guidance after intravenous delivery of mrGOG/DOX could significantly reduce tumor size and prolong animal survival over free DOX and non-magnetic guided groups. Augmented with NIR laser treatment for 5 min, the anti-cancer efficacy significantly improves with elevated cell apoptosis and reduced cell proliferation. Together with safety profiles from hematological as well as major organ histological analysis of treated animals, the mrGOG nanocomposite is an effective nanomaterial for combination chemo-photothermal cancer therapy.


Asunto(s)
Hipertermia Inducida , Nanocompuestos , Neoplasias , Animales , Línea Celular Tumoral , Doxorrubicina/farmacología , Liberación de Fármacos , Grafito , Fenómenos Magnéticos , Ratones , Ratones Desnudos , Fototerapia , Receptores de Bombesina
3.
Int J Mol Sci ; 22(13)2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-34206318

RESUMEN

Photosensitizers (PSs) have received significant attention recently in cancer treatment due to its theranostic capability for imaging and phototherapy. These PSs are highly responsive to light source of a suitable wavelength for image-guided cancer therapy from generated singlet oxygen and/or thermal heat. Various organic dye PSs show tremendous attenuation of tumor cells during cancer treatment. Among them, porphyrin and chlorophyll-based ultraviolet-visible (UV-Vis) dyes are employed for photodynamic therapy (PDT) by reactive oxygen species (ROS) and free radicals generated with 400-700 nm laser lights, which have poor tissue penetration depth. To enhance the efficacy of PDT, other light sources such as red light laser and X-ray have been suggested; nonetheless, it is still a challenging task to improve the light penetration depth for deep tumor treatment. To overcome this deficiency, near infrared (NIR) (700-900 nm) PSs, indocyanine green (ICG), and its derivatives like IR780, IR806 and IR820, have been introduced for imaging and phototherapy. These NIR PSs have been used in various cancer treatment modality by combining photothermal therapy (PTT) and/or PDT with chemotherapy or immunotherapy. In this review, we will focus on the use of different PSs showing photothermal/photodynamic response to UV-Vis or NIR-Vis light. The emphasis is a comprehensive review of recent smart design of PS-loaded nanocomposites for targeted delivery of PSs in light-activated combination cancer therapy.


Asunto(s)
Nanocompuestos/uso terapéutico , Neoplasias/terapia , Fotoquimioterapia , Fármacos Fotosensibilizantes/uso terapéutico , Medicina de Precisión , Humanos
4.
Int J Mol Sci ; 22(6)2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33804239

RESUMEN

Cancer is one of the deadliest diseases in human history with extremely poor prognosis. Although many traditional therapeutic modalities-such as surgery, chemotherapy, and radiation therapy-have proved to be successful in inhibiting the growth of tumor cells, their side effects may vastly limited the actual benefits and patient acceptance. In this context, a nanomedicine approach for cancer therapy using functionalized nanomaterial has been gaining ground recently. Considering the ability to carry various anticancer drugs and to act as a photothermal agent, the use of carbon-based nanomaterials for cancer therapy has advanced rapidly. Within those nanomaterials, reduced graphene oxide (rGO), a graphene family 2D carbon nanomaterial, emerged as a good candidate for cancer photothermal therapy due to its excellent photothermal conversion in the near infrared range, large specific surface area for drug loading, as well as functional groups for functionalization with molecules such as photosensitizers, siRNA, ligands, etc. By unique design, multifunctional nanosystems could be designed based on rGO, which are endowed with promising temperature/pH-dependent drug/gene delivery abilities for multimodal cancer therapy. This could be further augmented by additional advantages offered by functionalized rGO, such as high biocompatibility, targeted delivery, and enhanced photothermal effects. Herewith, we first provide an overview of the most effective reducing agents for rGO synthesis via chemical reduction. This was followed by in-depth review of application of functionalized rGO in different cancer treatment modalities such as chemotherapy, photothermal therapy and/or photodynamic therapy, gene therapy, chemotherapy/phototherapy, and photothermal/immunotherapy.


Asunto(s)
Grafito/uso terapéutico , Nanomedicina/tendencias , Nanoestructuras/uso terapéutico , Neoplasias/terapia , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Doxorrubicina/química , Doxorrubicina/uso terapéutico , Portadores de Fármacos/química , Portadores de Fármacos/uso terapéutico , Grafito/química , Humanos , Nanoestructuras/química , Neoplasias/patología , Fotoquimioterapia/métodos , Fototerapia/métodos
5.
Int J Mol Sci ; 21(15)2020 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-32707876

RESUMEN

In this work, we aimed to develop liposomal nanocomposites containing citric-acid-coated iron oxide magnetic nanoparticles (CMNPs) for dual magneto-photothermal cancer therapy induced by alternating magnetic field (AMF) and near-infrared (NIR) lasers. Toward this end, CMNPs were encapsulated in cationic liposomes to form nano-sized magnetic liposomes (MLs) for simultaneous magnetic hyperthermia (MH) in the presence of AMF and photothermia (PT) induced by NIR laser exposure, which amplified the heating efficiency for dual-mode cancer cell killing and tumor therapy. Since the heating capability is directly related to the amount of entrapped CMNPs in MLs, while the liposome size is important to allow internalization by cancer cells, response surface methodology was utilized to optimize the preparation of MLs by simultaneously maximizing the encapsulation efficiency (EE) of CMNPs in MLs and minimizing the size of MLs. The experimental design was performed based on the central composite rotatable design. The accuracy of the model was verified from the validation experiments, providing a simple and effective method for fabricating the best MLs, with an EE of 87% and liposome size of 121 nm. The CMNPs and the optimized MLs were fully characterized from chemical and physical perspectives. In the presence of dual AMF and NIR laser treatment, a suspension of MLs demonstrated amplified heat generation from dual hyperthermia (MH)-photothermia (PT) in comparison with single MH or PT. In vitro cell culture experiments confirmed the efficient cellular uptake of the MLs from confocal laser scanning microscopy due to passive accumulation in human glioblastoma U87 cells originated from the cationic nature of MLs. The inducible thermal effects mediated by MLs after endocytosis also led to enhanced cytotoxicity and cumulative cell death of cancer cells in the presence of AMF-NIR lasers. This functional nanocomposite will be a potential candidate for bimodal MH-PT dual magneto-photothermal cancer therapy.


Asunto(s)
Glioblastoma/tratamiento farmacológico , Hipertermia Inducida/métodos , Liposomas/química , Nanopartículas de Magnetita/química , Nanocompuestos/química , Fototerapia/métodos , Células 3T3 , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Ácido Cítrico/química , Endocitosis/efectos de los fármacos , Glioblastoma/radioterapia , Humanos , Hipertermia , Hipertermia Inducida/instrumentación , Rayos Láser , Liposomas/síntesis química , Liposomas/ultraestructura , Campos Magnéticos , Nanopartículas de Magnetita/efectos de la radiación , Nanopartículas de Magnetita/ultraestructura , Ratones , Microscopía Electrónica de Transmisión , Nanocompuestos/efectos de la radiación , Tamaño de la Partícula
6.
Int J Mol Sci ; 21(8)2020 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-32294917

RESUMEN

Recombinant tissue plasminogen activator (rtPA) is the only thrombolytic agent that has been approved by the FDA for treatment of ischemic stroke. However, a high dose intravenous infusion is required to maintain effective drug concentration, owing to the short half-life of the thrombolytic drug, whereas a momentous limitation is the risk of bleeding. We envision a dual targeted strategy for rtPA delivery will be feasible to minimize the required dose of rtPA for treatment. For this purpose, rtPA and fibrin-avid peptide were co-immobilized to poly(lactic-co-glycolic acid) (PLGA) magnetic nanoparticles (PMNP) to prepare peptide/rtPA conjugated PMNPs (pPMNP-rtPA). During preparation, PMNP was first surface modified with avidin, which could interact with biotin. This is followed by binding PMNP-avidin with biotin-PEG-rtPA (or biotin-PEG-peptide), which was prepared beforehand by binding rtPA (or peptide) to biotin-PEG-maleimide while using click chemistry between maleimide and the single -SH group in rtPA (or peptide). The physicochemical property characterization indicated the successful preparation of the magnetic nanoparticles with full retention of rtPA fibrinolysis activity, while biological response studies underlined the high biocompatibility of all magnetic nanoparticles from cytotoxicity and hemolysis assays in vitro. The magnetic guidance and fibrin binding effects were also confirmed, which led to a higher thrombolysis rate in vitro using PMNP-rtPA or pPMNP-rtPA when compared to free rtPA after static or dynamic incubation with blood clots. Using pressure-dependent clot lysis model in a flow system, dual targeted pPMNP-rtPA could reduce the clot lysis time for reperfusion by 40% when compared to free rtPA at the same drug dosage. From in vivo targeted thrombolysis in a rat embolic model, pPMNP-rtPA was used at 20% of free rtPA dosage to restore the iliac blood flow in vascular thrombus that was created by injecting a blood clot to the hind limb area.


Asunto(s)
Portadores de Fármacos/química , Fibrinolíticos/química , Fibrinolíticos/farmacología , Nanopartículas de Magnetita/química , Péptidos/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Activador de Tejido Plasminógeno/administración & dosificación , Animales , Avidina/química , Fenómenos Químicos , Modelos Animales de Enfermedad , Sistemas de Liberación de Medicamentos , Desarrollo de Medicamentos , Embolia/tratamiento farmacológico , Embolia/etiología , Fibrinólisis/efectos de los fármacos , Ratas , Proteínas Recombinantes/administración & dosificación , Análisis Espectral , Nanomedicina Teranóstica , Termogravimetría , Terapia Trombolítica/métodos , Trombosis/tratamiento farmacológico
7.
Curr Pharm Des ; 25(13): 1490-1504, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31109270

RESUMEN

MNPs find numerous important biomedical applications owing to their high biocompatibility and unique magnetic properties at the bottom level. Among several other biomedical applications, MNPs are gaining importance in treating various kinds of cancer either as a hyperthermia agent alone or as a drug/gene carrier for single or combined therapies. At the same time, another type of nano-carrier with lipid bilayer, i.e. liposomes, has also emerged as a platform for administration of pharmaceutical drugs, which sees increasing importance as a drug/gene carrier in cancer therapy due to its excellent biocompatibility, tunable particle size and the possibility for surface modification to overcome biological barriers and to reach targeted sites. MLs that combine MNPs with liposomes are endowed with advantages of both MNPs and liposomes and are gaining importance for cancer therapy in various modes. Hence, we will start by reviewing the synthesis methods of MNPs and MLs, followed by a comprehensive assessment of current strategies to apply MLs for different types of cancer treatments. These will include thermo-chemotherapy using MLs as a triggered releasing agent to deliver drugs/genes, photothermal/ photodynamic therapy and combined imaging and cancer therapy.


Asunto(s)
Sistemas de Liberación de Medicamentos , Hipertermia Inducida , Liposomas , Nanopartículas de Magnetita , Neoplasias/terapia , Fotoquimioterapia , Animales , Terapia Genética , Humanos , Fenómenos Magnéticos
8.
Nanomedicine ; 20: 101992, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30981818

RESUMEN

In previously published studies, intra-arterial (i.a.), but not intravenous (i.v.) delivery of recombinant tissue-type plasminogen activator (rtPA) immobilized on the surface of magnetic nanoparticles induces thrombolysis by magnetic targeting. We asked whether i.v. delivery of protected rtPA in a thermosensitive magnetoliposome (TML@rtPA) may achieve target thrombolysis. PEGylated TML@rtPA was optimized and characterized; controlled release of rtPA was achieved by thermodynamic and magnetic manipulation in vitro. The lysis index of TML@rtPA incubated with blood at 43 °C vs. 37 °C was 53 ±â€¯11% vs. 81 ±â€¯3% in thromboelastograms, suggesting thermosensitive thrombolysis of TML@rtPA. In a rat embolic model with superfusion of 43 °C saline on a focal spot on the iliac artery with clot lodging, release of rtPA equivalent to 20% regular dose from TML@rtPA administered i.a. vs. i.v. significantly restored iliac blood flow 15 vs. 55 min after clot lodging, respectively. TML@rtPA with magnetic guiding and focal hyperthermia may be potentially amendable to target thrombolysis.


Asunto(s)
Hipertermia Inducida , Fenómenos Magnéticos , Terapia Trombolítica , Activador de Tejido Plasminógeno/administración & dosificación , Administración Intravenosa , Animales , Materiales Biocompatibles/química , Liposomas , Masculino , Nanocompuestos/química , Nanocompuestos/ultraestructura , Tamaño de la Partícula , Ratas Sprague-Dawley , Temperatura , Trombosis
9.
Nanomaterials (Basel) ; 8(4)2018 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-29584656

RESUMEN

To develop a pH-sensitive dual targeting magnetic nanocarrier for chemo-phototherapy in cancer treatment, we prepared magnetic graphene oxide (MGO) by depositing Fe3O4 magnetic nanoparticles on graphene oxide (GO) through chemical co-precipitation. MGO was modified with polyethylene glycol (PEG) and cetuximab (CET, an epidermal growth factor receptor (EGFR) monoclonal antibody) to obtain MGO-PEG-CET. Since EGFR was highly expressed on the tumor cell surface, MGO-PEG-CET was used for dual targeted delivery an anticancer drug doxorubicin (DOX). The physico-chemical properties of MGO-PEG-CET were fully characterized by dynamic light scattering, transmission electron microscopy, X-ray diffraction, Fourier transform Infrared spectroscopy, thermogravimetric analysis, and superconducting quantum interference device. Drug loading experiments revealed that DOX adsorption followed the Langmuir isotherm with a maximal drug loading capacity of 6.35 mg/mg, while DOX release was pH-dependent with more DOX released at pH 5.5 than pH 7.4. Using quantum-dots labeled nanocarriers and confocal microscopy, intracellular uptakes of MGO-PEG-CET by high EGFR-expressing CT-26 murine colorectal cells was confirmed to be more efficient than MGO. This cellular uptake could be inhibited by pre-incubation with CET, which confirmed the receptor-mediated endocytosis of MGO-PEG-CET. Magnetic targeted killing of CT-26 was demonstrated in vitro through magnetic guidance of MGO-PEG-CET/DOX, while the photothermal effect could be confirmed in vivo and in vitro after exposure of MGO-PEG-CET to near-infrared (NIR) laser light. In addition, the biocompatibility tests indicated MGO-PEG-CET showed no cytotoxicity toward fibroblasts and elicited minimum hemolysis. In vitro cytotoxicity tests showed the half maximal inhibitory concentration (IC50) value of MGO-PEG-CET/DOX toward CT-26 cells was 1.48 µg/mL, which was lower than that of MGO-PEG/DOX (2.64 µg/mL). The IC50 value could be further reduced to 1.17 µg/mL after combining with photothermal therapy by NIR laser light exposure. Using subcutaneously implanted CT-26 cells in BALB/c mice, in vivo anti-tumor studies indicated the relative tumor volumes at day 14 were 12.1 for control (normal saline), 10.1 for DOX, 9.5 for MGO-PEG-CET/DOX, 5.8 for MGO-PEG-CET/DOX + magnet, and 0.42 for MGO-PEG-CET/DOX + magnet + laser. Therefore, the dual targeting MGO-PEG-CET/DOX could be suggested as an effective drug delivery system for anticancer therapy, which showed a 29-fold increase in therapeutic efficacy compared with control by combining chemotherapy with photothermal therapy.

10.
Medicine (Baltimore) ; 96(52): e9541, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29384973

RESUMEN

European and Northern American healthcare authorities increasingly encourage the use of Patient Reported Outcome Measures (PROMs) that complement clinical and laboratory assessments to help holistically evaluate reconstructive outcomes. This is the first study to evaluate PROMs in cleft lip/palate patients who have, or have not, undergone secondary alveolar bone grafting (SABG).A PROMs study was conducted; 40 consecutive consenting cleft lip/palate children between 8 and 14 years old were included. Twenty patients did, and 20 patients did not, have SABG. PROMs scores from children and parents in the 2 groups were compared.Forty patients completed the trial. No significant differences in total score from the Chang Gung Short Form-15 (CGSF-15) were found between children and their parents. Children with SABG reported no more oral-nasal regurgitation than children without SABG, but tended to report more nasal obstruction. There were no statistically significant differences in parent reported outcomes between the 2 groups.Cleft lip/palate patients who underwent SABG reported significantly less nasal regurgitation and more nasal obstruction compared to those patients who did not undergo SABG.


Asunto(s)
Injerto de Hueso Alveolar/métodos , Labio Leporino/cirugía , Fisura del Paladar/cirugía , Padres/psicología , Medición de Resultados Informados por el Paciente , Adolescente , Injerto de Hueso Alveolar/psicología , Niño , Femenino , Humanos , Relaciones Interpersonales , Masculino , Dolor Postoperatorio/epidemiología , Apariencia Física , Estudios Prospectivos , Calidad de Vida , Reproducibilidad de los Resultados , Habla
11.
Appl Biochem Biotechnol ; 161(1-8): 181-94, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19777379

RESUMEN

A circulating packed-bed bioreactor system using fibrous nonwoven fabric as the immobilization matrix was suitable for simultaneous cell growth and immobilization of Rhizopus oryzae fungus cells, which could be used for lipase-mediated production of biodiesel by methanolysis of soybean oil. Response surface methodology and 5-level-5-factor central composite rotatable design was proved to be a powerful tool for the optimization of methanolysis conditions catalyzed by immobilized R. oryzae whole cell biocatalyst. A quadratic polynomial regression model was used to analyze the relationship between the yield and the significant reaction parameters. The analysis confirmed that water content, molar ratio of methanol to oil, cell weight, and reaction time were the significant factors affecting the yield at a 95% confidence level (p < 0.05). Under the optimum condition at 10.97% (w/w) water content, 0.64 molar ratio of methanol to oil, 2.25% (w/w) cell weight, and 23.3 h reaction time, the predicted value of yield was 72.6%. Validation experiments with yields of 70.77 +/- 2.46% verified the availability and the accuracy of the model.


Asunto(s)
Biocombustibles , Reactores Biológicos , Proteínas Fúngicas/metabolismo , Lipasa/metabolismo , Rhizopus/metabolismo , Catálisis , Técnicas de Cultivo de Célula , Modelos Teóricos , Aceite de Soja/metabolismo
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