RESUMO
Dye-decolorizing peroxidases (DyPs) are recently identified microbial enzymes that have been used in several Biotechnology applications from wastewater treatment to lignin valorization. However, their properties and mechanism of action still have many open questions. Their heme-containing active site is buried by three conserved flexible loops with a putative role in modulating substrate access and enzyme catalysis. Here, we investigated the role of a conserved glutamate residue in stabilizing interactions in loop 2 of A-type DyPs. First, we did site saturation mutagenesis of this residue, replacing it with all possible amino acids in bacterial DyPs from Bacillus subtilis (BsDyP) and from Kitasatospora aureofaciens (KaDyP1), the latter being characterized here for the first time. We screened the resulting libraries of variants for activity towards ABTS and identified variants with increased catalytic efficiency. The selected variants were purified and characterized for activity and stability. We furthermore used Molecular Dynamics simulations to rationalize the increased catalytic efficiency and found that the main reason is the electron channeling becoming easier from surface-exposed tryptophans. Based on our findings, we also propose that this glutamate could work as a pH switch in the wild-type enzyme, preventing intracellular damage.
Assuntos
Bacillus subtilis , Corantes , Ácido Glutâmico , Peroxidases , Ácido Glutâmico/química , Ácido Glutâmico/metabolismo , Corantes/química , Corantes/metabolismo , Bacillus subtilis/enzimologia , Peroxidases/química , Peroxidases/metabolismo , Peroxidases/genética , Simulação de Dinâmica Molecular , Engenharia de Proteínas , Mutagênese Sítio-DirigidaRESUMO
Gold core silica shell (AuMSS) nanorods present excellent physicochemical properties that allow their application as photothermal and drug delivery agents. Herein, AuMSS nanorods were dual-functionalized with Polyethylene glycol methyl ether (PEG-CH3 ) and Gelatin (GEL) to enhance both the colloidal stability and uptake by HeLa cancer cells. Additionally, the AuMSS nanorods were combined for the first time with IR780 (a heptamethine cyanine molecule) and its photothermal and photodynamic capacities were determined. The obtained results reveal that the encapsulation of IR780 (65 µg per AuMSS mg) increases the photothermal conversion efficiency of AuMSS nanorods by 10%, and this enhanced heat generation was maintained even after three irradiation cycles with a NIR (808 nm) laser. Moreover, the IR780-loaded AuMSS/T-PEG-CH3 /T-GEL presented ≈2-times higher uptake in HeLa cells, when compared to the non-coated counterparts, and successfully mediated the light-triggered generation of reactive oxygen species. Overall, the combination of photodynamic and photothermal therapy mediated by IR780-loaded AuMSS/T-PEG-CH3 /T-GEL nanorods effectively promoted the ablation of HeLa cancer cells.
Assuntos
Antineoplásicos , Gelatina/química , Indóis/química , Nanotubos/química , Fotoquimioterapia , Antineoplásicos/química , Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Ouro/química , Células HeLa , Humanos , Neoplasias , Terapia Fototérmica , Polietilenoglicóis/química , Dióxido de Silício/químicaRESUMO
Bacillus subtilis BsDyP belongs to class I of the dye-decolorizing peroxidase (DyP) family of enzymes and is an interesting biocatalyst due to its high redox potential, broad substrate spectrum and thermostability. This work reports the optimization of BsDyP using directed evolution for improved oxidation of 2,6-dimethoxyphenol, a model lignin-derived phenolic. After three rounds of evolution, one variant was identified displaying 7-fold higher catalytic rates and higher production yields as compared to the wild-type enzyme. The analysis of X-ray structures of the wild type and the evolved variant showed that the heme pocket is delimited by three long conserved loop regions and a small α helix where, incidentally, the mutations were inserted in the course of evolution. One loop in the proximal side of the heme pocket becomes more flexible in the evolved variant and the size of the active site cavity is increased, as well as the width of its mouth, resulting in an enhanced exposure of the heme to solvent. These conformational changes have a positive functional role in facilitating electron transfer from the substrate to the enzyme. However, they concomitantly resulted in decreasing the enzyme's overall stability by 2 kcal mol-1, indicating a trade-off between functionality and stability. Furthermore, the evolved variant exhibited slightly reduced thermal stability compared to the wild type. The obtained data indicate that understanding the role of loops close to the heme pocket in the catalysis and stability of DyPs is critical for the development of new and more powerful biocatalysts: loops can be modulated for tuning important DyP properties such as activity, specificity and stability.
Assuntos
Bacillus subtilis/enzimologia , Proteínas de Bactérias/metabolismo , Heme/química , Mutação , Peroxidase/química , Peroxidase/metabolismo , Proteínas de Bactérias/genética , Catálise , Domínio Catalítico , Corantes/química , Corantes/metabolismo , Estabilidade Enzimática , Heme/metabolismo , Concentração de Íons de Hidrogênio , Oxirredução , Peroxidase/genética , Conformação ProteicaRESUMO
The application of nanomaterials is regarded nowadays as a highly promising approach for overcoming the limitations of the currently available cancer treatments, contributing for the creation of more effective, precise, and safer therapies. In the last years, organosilica nanoparticles arisen as alternatives to the most common mesoporous silica nanoparticles. The organosilica nanoparticles combine the advantages of the mesoporous silica, such as structural stability and mesoporous structure, with the increased biocompatibility and biodegradability of organic materials. Therefore, the variety of organic bridges that can be incorporated into the silica matrix allowed the development of new and exciting compositions, properties, and functions for improving the therapeutic effectiveness of the anticancer nanomedicines. In this review, the strategies that have been explored to create stimuli-responsive organosilica-based drug delivery systems are highlighted, describing the practical approaches and mechanisms controlling the drug release. Additionally, the organosilica nanoparticles surface modifications aimed for increasing the blood circulation time and the tumor targeting are also described.
Assuntos
Portadores de Fármacos , Nanopartículas , Compostos de Organossilício , Animais , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Humanos , Nanopartículas/administração & dosagem , Nanopartículas/química , Compostos de Organossilício/administração & dosagem , Compostos de Organossilício/química , PorosidadeRESUMO
3D tumor spheroids have arisen in the last years as potent tools for the in vitro screening of novel anticancer therapeutics. Nevertheless, to increase the reproducibility and predictability of the data originated from the spheroids it is still necessary to develop or optimize the techniques used for spheroids' physical and biomolecular characterization. Fluorescence microscopy, such as confocal laser scanning microscopy (CLSM), is a tool commonly used by researchers to characterize spheroids structure and the antitumoral effect of novel therapeutics. However, its application in spheroids' analysis is hindered by the limited light penetration in thick samples. For this purpose, optical clearing solutions have been explored to increase the spheroids' transparency by reducing the light scattering. In this study, the influence of agitation conditions (i.e., static, horizontal agitation, and rotatory agitation) on the ClearT and ClearT2 methods' clearing efficacy and tumor spheroids' imaging by CLSM was characterized. The obtained results demonstrate that the ClearT method results in the improved imaging of the spheroids interior, whereas the ClearT2 resulted in an increased propidium iodide mean fluorescence intensity as well as a higher signal depth in the Z-axis. Additionally, for both methods, the best clearing results were obtained for the spheroids treated under the rotatory agitation. In general, this work provides new insights on the ClearT and ClearT2 clearing methodologies and their utilization for improving the reproducibility of the data obtained through the CLSM, such as the analysis of the cell death in response to therapeutics administration.
Assuntos
Microscopia de Fluorescência , Imagem Óptica , Esferoides Celulares/citologia , Esferoides Celulares/patologia , Linhagem Celular Tumoral , Humanos , Microscopia Confocal , Imagem Óptica/métodosRESUMO
Macroscale delivery systems that can be locally implanted on the tumor tissue as well as avoid all the complications associated to the systemic delivery of therapeutics have captured researchers' attention, in recent years. Particularly, the microneedle-based devices can be used to efficiently deliver both small and macro-molecules, like chemotherapeutics, proteins, and genetic material, along with nanoparticle-based anticancer therapies. Such capacity prompted the application of microneedle devices for the development of new anticancer vaccines that can permeate the tumor tissue and simultaneously improve the effectiveness of therapeutic agents. Based on the promising results demonstrated by the microneedle systems in the local administration of anticancer therapeutics, this review summarizes the different microneedle formulations developed up to now aimed for application on cancer therapy (mphasizing those produced with polymers). Additionally, the microneedles' general properties, type of therapeutic approach and its main advantages are also highlighted.
Assuntos
Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos/instrumentação , Neoplasias/tratamento farmacológico , Animais , Humanos , Agulhas , Vacinas/administração & dosagemRESUMO
Gold core mesoporous silica shell (AuMSS) nanorods are multifunctional nanomedicines that can act simultaneously as photothermal, drug delivery, and bioimaging agents. Nevertheless, it is reported that once administrated, nanoparticles can be coated with blood proteins, forming a protein corona, that directly impacts on nanomedicines' circulation time, biodistribution, and therapeutic performance. Therefore, it become crucial to develop novel alternatives to improve nanoparticles' half-life in the bloodstream. In this work, Polyethylenimine (PEI) and Red blood cells (RBC)-derived membranes were combined for the first time to functionalize AuMSS nanorods and simultaneously load acridine orange (AO). The obtained results revealed that the RBC-derived membranes promoted the neutralization of the AuMSS' surface charge and consequently improved the colloidal stability and biocompatibility of the nanocarriers. Indeed, the in vitro data revealed that PEI/RBC-derived membranes' functionalization also improved the nanoparticles' cellular internalization and was capable of mitigating the hemolytic effects of AuMSS and AuMSS/PEI nanorods. In turn, the combinatorial chemo-photothermal therapy mediated by AuMSS/PEI/RBC_AO nanorods was able to completely eliminate HeLa cells, contrasting with the less efficient standalone therapies. Such data reinforce the potential of AuMSS nanomaterials to act simultaneously as photothermal and chemotherapeutic agents.
Assuntos
Antineoplásicos , Nanotubos , Neoplasias , Humanos , Células HeLa , Terapia Fototérmica , Membrana Eritrocítica , Dióxido de Silício , Ouro , Distribuição Tecidual , Fototerapia , Doxorrubicina/farmacologia , Neoplasias/tratamento farmacológicoRESUMO
Gold-based nanoparticles present excellent optical properties that propelled their widespread application in biomedicine, from bioimaging to photothermal applications. Nevertheless, commonly employed manufacturing methods for gold-based nanoparticles require long periods and laborious protocols that reduce cost-effectiveness and scalability. Herein, a novel methodology was used for producing gold-alginic acid nanohybrids (Au-Alg-NH) with photothermal capabilities. This was accomplished by promoting the in situ reduction and nucleation of gold ions throughout a matrix of alginic acid by using ascorbic acid. The results obtained reveal that the Au-Alg-NHs present a uniform size distribution and a spike-like shape. Moreover, the nanomaterials were capable to mediate a temperature increase of ≈11°C in response to the irradiation with a near-infrared region (NIR) laser (808 nm, 1.7 W cm-2 ). The in vitro assays showed that Au-Alg-NHs were able to perform a NIR light-triggered ablation of cancer cells (MCF-7), being observed a reduction in the cell viability to ≈27%. Therefore, the results demonstrate that this novel methodology holds the potential for producing Au-Alg-NH with photothermal capacity and higher translatability to the clinical practice, namely for cancer therapy.
Assuntos
Nanopartículas Metálicas , Nanopartículas , Neoplasias , Ácido Algínico , Ouro , Terapia Fototérmica , Fototerapia , Nanopartículas Metálicas/uso terapêutico , Neoplasias/terapiaRESUMO
Dye-decolorizing peroxidases (DyPs) are heme-containing enzymes that are structurally unrelated to other peroxidases. Some DyPs show high potential for applications in biotechnology, which critically depends on the stability and redox potential (E°') of the enzyme. Here we provide a comparative analysis of UV-Vis- and surface-enhanced resonance Raman-based spectroelectrochemical methods for determination of the E°' of DyPs from two different organisms, and their variants generated targeting E°' upshift. We show that substituting the highly conserved Arginine in the distal side of the heme pocket by hydrophobic amino acid residues impacts the heme architecture and redox potential of DyPs from the two organisms in a very distinct manner. We demonstrate the advantages and drawbacks of the used spectroelectrochemical approaches, which is relevant for other heme proteins that contain multiple heme centers or spin populations.
RESUMO
Dye-decolorizing Peroxidases (DyPs) are heme-containing enzymes in fungi and bacteria that catalyze the reduction of hydrogen peroxide to water with concomitant oxidation of various substrates, including anthraquinone dyes, lignin-related phenolic and non-phenolic compounds, and metal ions. Investigation of DyPs has shed new light on peroxidases, one of the most extensively studied families of oxidoreductases; still, details of their microbial physiological role and catalytic mechanisms remain to be fully disclosed. They display a distinctive ferredoxin-like fold encompassing anti-parallel ß-sheets and α-helices, and long conserved loops surround the heme pocket with a role in catalysis and stability. A tunnel routes H2O2 to the heme pocket, whereas binding sites for the reducing substrates are in cavities near the heme or close to distal aromatic residues at the surface. Variations in reactions, the role of catalytic residues, and mechanisms were observed among different classes of DyP. They were hypothetically related to the presence or absence of distal H2O molecules in the heme pocket. The engineering of DyPs for improved properties directed their biotechnological applications, primarily centered on treating textile effluents and degradation of other hazardous pollutants, to fields such as biosensors and valorization of lignin, the most abundant renewable aromatic polymer. In this review, we track recent research contributions that furthered our understanding of the activity, stability, and structural properties of DyPs and their biotechnological applications. Overall, the study of DyP-type peroxidases has significant implications for environmental sustainability and the development of new bio-based products and materials with improved end-of-life options via biodegradation and chemical recyclability, fostering the transition to a sustainable bio-based industry in the circular economy realm.
Assuntos
Lignina , Peroxidases , Peroxidases/química , Biocatálise , Lignina/química , Peróxido de Hidrogênio , Heme/química , Corantes/química , Corantes/metabolismoRESUMO
Cancer nanomedicines are designed to encapsulate different therapeutic agents, prevent their premature release, and deliver them specifically to cancer cells, due to their ability to preferentially accumulate in tumor tissue. However, after intravenous administration, nanoparticles immediately interact with biological components that facilitate their recognition by the immune system, being rapidly removed from circulation. Reports show that less than 1% of the administered nanoparticles effectively reach the tumor site. This suboptimal pharmacokinetic profile is pointed out as one of the main factors for the nanoparticles' suboptimal therapeutic effectiveness and poor translation to the clinic. Therefore, an extended blood circulation time may be crucial to increase the nanoparticles' chances of being accumulated in the tumor and promote a site-specific delivery of therapeutic agents. For that purpose, the understanding of the forces that govern the nanoparticles' interaction with biological components and the impact of the physicochemical properties on the in vivo fate will allow the development of novel and more effective nanomedicines. Therefore, in this review, the nano-bio interactions are summarized. Moreover, the application of cell-derived vesicles for extending the blood circulation time and tumor accumulation is reviewed, focusing on the advantages and shortcomings of each cell source.
Assuntos
Biomimética , Neoplasias , Humanos , Nanomedicina , Neoplasias/tratamento farmacológicoRESUMO
Metallic-based nanoparticles present a unique set of physicochemical properties that support their application in different fields, such as electronics, medical diagnostics, and therapeutics. Particularly, in cancer therapy, the plasmonic resonance, magnetic behavior, X-ray attenuation, and radical oxygen species generation capacity displayed by metallic nanoparticles make them highly promising theragnostic solutions. Nevertheless, metallic-based nanoparticles are often associated with some toxicological issues, lack of colloidal stability, and establishment of off-target interactions. Therefore, researchers have been exploiting the combination of metallic nanoparticles with other materials, inorganic (e.g., silica) and/or organic (e.g., polymers). In terms of biological performance, metal-polymer conjugation can be advantageous for improving biocompatibility, colloidal stability, and tumor specificity. In this review, the application of metallic-polymer nanoconjugates/nanohybrids as a multifunctional all-in-one solution for cancer therapy will be summarized, focusing on the physicochemical properties that make metallic nanomaterials capable of acting as imaging and/or therapeutic agents. Then, an overview of the main advantages of metal-polymer conjugation as well as the most common structural arrangements will be provided. Moreover, the application of metallic-polymer nanoconjugates/nanohybrids made of gold, iron, copper, and other metals in cancer therapy will be discussed, in addition to an outlook of the current solution in clinical trials.
RESUMO
Cancer light-triggered hyperthermia mediated by nanomaterials aims to eliminate cancer cells by inducing localized temperature increases to values superior to 42 °C, upon irradiation with a laser. Among the different nanomaterials with photothermal capacity, the gold-based nanoparticles have been widely studied due to their structural plasticity and advantageous physicochemical properties. Herein, a novel and straightforward methodology was developed to produce gold nanoclusters coated with mesoporous silica (AuMSS), using glutathione (GSH) to mediate the formation of the gold clusters. The obtained results revealed that GSH is capable of triggering and control the aggregation of gold nanospheres, which enhanced the absorption of radiation in the NIR region of the spectra. Moreover, the produced AuMSS nanoclusters mediated a maximum temperature increase of 20 °C and were able to encapsulate a drug model (acridine orange). In addition, these AuMSS nanoclusters were also biocompatible with both healthy (fibroblasts) and carcinogenic (cervical cancer) cells, at a maximum tested concentration of 200 µg/mL. Nevertheless, the AuMSS nanoclusters' NIR light-triggered heat generation successfully reduced the viability of cervical cancer cells by about 80%. This confirms the potential of the AuMSS nanoclusters to be applied in cancer therapy, namely as theragnostic agents.
RESUMO
Combinatorial therapies based on the simultaneous administration of multiple drugs can lead to synergistic effects, increasing the efficacy of the cancer therapy. However, it is crucial to develop new delivery systems that can increase the drugs' therapeutic selectivity and efficacy. Gold core silica shell (AuMSS) nanoparticles present physicochemical properties that allow their simultaneous application as drug delivery and imaging agents. Herein, poly(ethylene glycol) was modified with 4-methoxybenzamide and 3-(triethoxysilyl)propyl isocyanate (TPANIS) to create a novel surface functionalization capable of improving the colloidal stability and specificity of AuMSS nanospheres towards cancer cells. Moreover, a dual drug combination based on Doxorubicin (DOX) and Acridine orange (AO) was characterized and administered using the AuMSS-TPANIS nanospheres. The obtained results show that the DOX:AO drug combination can mediate a synergistic therapeutic effect in both HeLa and MCF-7 cells, particularly at the 2:1, 1:1, and 1:2 ratios. Additionally, the TPANIS functionalization increased the AuMSS nanospheres colloidal stability and selectivity towards MCF-7 cancer cells (overexpressing sigma receptors). Such also resulted in an enhanced cytotoxic effect against MCF-7 cells when administering the DOX:AO drug combination with the AuMSS-TPANIS nanospheres. Overall, the obtained results confirm the therapeutic potential of the DOX:AO drug combination as well as the targeting capacity of AuMSS-TPANIS, supporting its application in the cancer-targeted combinatorial chemotherapy.
Assuntos
Laranja de Acridina/farmacologia , Doxorrubicina/farmacologia , Ouro/química , Nanosferas/química , Neoplasias/tratamento farmacológico , Dióxido de Silício/química , Laranja de Acridina/química , Protocolos de Quimioterapia Combinada Antineoplásica/química , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Benzamidas/química , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Sistemas de Liberação de Medicamentos/métodos , Células HeLa , Humanos , Células MCF-7 , Neoplasias/metabolismo , Polietilenoglicóis/químicaRESUMO
Cancer photothermal therapy (PTT) has captured the attention of researchers worldwide due to its localized and trigger-activated therapeutic effect. In this field, nanomaterials capable of converting the energy of the irradiation light into heat have been showing promising results in several pre-clinical and clinical assays. Such a therapeutic modality takes advantage of the innate capacity of nanomaterials to accumulate in the tumor tissue and their capacity to interact with NIR laser irradiation to exert a therapeutic effect. Therefore, several nanostructures composed of different materials and organizations for mediating a photothermal effect have been developed. In this review, the most common inorganic nanomaterials, such as gold, carbon-based materials, tungsten, copper, molybdenum, and iron oxide, which have been explored for mediating a tumor-localized photothermal effect, are summarized. Moreover, the physicochemical parameters of nanoparticles that influence the PTT effectiveness are discussed and the recent clinical advances involving inorganic nanomaterial-mediated cancer photothermal therapy are also presented.
Assuntos
Nanoestruturas/administração & dosagem , Neoplasias/terapia , Terapia Fototérmica , Animais , Carbono/administração & dosagem , Humanos , Metais Pesados/administração & dosagemRESUMO
The plasmonic photothermal properties of gold nanoparticles have been widely explored in the biomedical field to mediate a photothermal effect in response to the irradiation with an external light source. Particularly, in cancer therapy, the physicochemical properties of gold-based nanomaterials allow them to efficiently accumulate in the tumor tissue and then mediate the light-triggered thermal destruction of cancer cells with high spatial-temporal control. Nevertheless, the gold nanomaterials can be produced with different shapes, sizes, and organizations such as nanospheres, nanorods, nanocages, nanoshells, and nanoclusters. These gold nanostructures will present different plasmonic photothermal properties that can impact cancer thermal ablation. This review analyses the application of gold-based nanomaterials in cancer photothermal therapy, emphasizing the main parameters that affect its light-to-heat conversion efficiency and consequently the photothermal potential. The different shapes/organizations (clusters, shells, rods, stars, cages) of gold nanomaterials and the parameters that can be fine-tuned to improve the photothermal capacity are presented. Moreover, the gold nanostructures combination with other materials (e.g. silica, graphene, and iron oxide) or small molecules (e.g. indocyanine green and IR780) to improve the nanomaterials photothermal capacity is also overviewed.
Assuntos
Hipertermia Induzida , Nanopartículas Metálicas , Nanoestruturas , Neoplasias , Ouro , Humanos , Nanomedicina , Neoplasias/terapia , FototerapiaRESUMO
The combination of photothermal and chemo- therapies displays a high potential to increase the efficacy of the cancer treatments or even promote their eradication. In this study, the micromoulding and electrospraying techniques were combined to produce polyvinylpyrrolidone microneedles coated with chitosan and poly (vinyl alcohol) for mediating the delivery of doxorubicin and AuMSS nanorods (Dox@MicroN) to cancer cells. The microneedles' physicochemical characterization demonstrated that the electrospraying technique can be used to produce a layer-by-layer coating consisting of layers of doxorubicin-loaded chitosan and AuMSS enriched poly (vinyl alcohol). Further, the Dox@MicroN patches presented a good photothermal capacity leading to a temperature increase of 12 °C under near-infrared irradiation (808 nm, 1.7 W/cm-2 for 5 min), which in conjugation with the chitosan' pH sensitivity could be used to control the doxorubicin release. Moreover, the microneedles were able to penetrate the tumor-mimicking agarose gel and promote a layer dependent drug release. Additionally, the Dox@MicroN patches' capacity to simultaneously mediate the chemo- and photothermal-therapies rendered a superior cytotoxic effect against the cervical cancer cells. Overall, the Dox@MicroN patches demonstrated to be a simple macroscale delivery device that can be used to mediate the local administration of new drug-photothermal combinations, avoiding all the issues related to the systemic administration of anti-cancer therapeutics.
Assuntos
Antineoplásicos/administração & dosagem , Quitosana/química , Doxorrubicina/administração & dosagem , Álcool de Polivinil/química , Neoplasias do Colo do Útero/tratamento farmacológico , Linhagem Celular , Linhagem Celular Tumoral , Liberação Controlada de Fármacos , Feminino , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Agulhas , Fototerapia/métodos , Povidona/químicaRESUMO
Gold-core mesoporous silica shell (AuMSS) nanorods unique physicochemical properties makes them versatile and promising nanomedicines for cancer photothermal therapy. Nevertheless, these nanomaterials present a reduced half-life in the blood and poor specificity towards the tumor tissue. Herein, d-α-Tocopherol polyethylene glycol 1000 succinate (TPGS) and Hyaluronic Acid (HA) were combined for the first time to improve the AuMSS nanorods biological performance. The obtained results revealed that AuMSS surface functionalization induced the surface charge neutralization, from -28⯱â¯10â¯mV to -3⯱â¯5â¯mV and -10⯱â¯4â¯mV for AuMSS-TPGS-HA (1:1) and (4:1) formulations, without impacting on nanomaterials' photothermal capacity. Moreover, the AuMSS functionalization improved the nanomaterials hemocompatibility and selectivity towards the cancer cells, particularly in the AuMSS-TPGS-HA (4:1) formulation. Furthermore, both formulations were able to mediate an on-demand photothermal effect, that induced the HeLa cancer cells death, confirming its potential for being applied as targeted multifunctional theragnostic nanomedicines.
Assuntos
Antineoplásicos/farmacologia , Materiais Biocompatíveis/farmacologia , Fototerapia , Antineoplásicos/química , Materiais Biocompatíveis/química , Sobrevivência Celular/efeitos dos fármacos , Ouro/química , Ouro/farmacologia , Células HeLa , Humanos , Ácido Hialurônico/síntese química , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Nanotubos/química , Tamanho da Partícula , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Succinatos/química , Succinatos/farmacologia , Propriedades de Superfície , Vitamina E/química , Vitamina E/farmacologiaRESUMO
Cancer is one of the major world public health problems and the currently available treatments are nonspecific and ineffective. This reality highlights the importance of developing novel therapeutic approaches. In this field, multifunctional nanomedicines have the potential to revolutionize the currently available treatments. These unique nanodevices can simultaneously act as therapeutic and imaging agents allowing the real-time monitoring of the nanoparticles biodistribution and the treatment outcome. Among the different nanoparticles, the gold-core silica shell (AuMSS) nanoparticles advantageous physicochemical and biological properties make them promising nanoplatforms for cancer therapy. Nevertheless, their successful application as an effective cancer nanomedicine is limited by the unfavorable pharmacokinetics and uncontrolled release of the therapeutic payloads. Herein, a new polymeric coating for AuMSS nanospheres was developed by combining different ratios (25/75, 50/50 and 75/25) of two materials, Poly-2-ethyl-2-oxazoline (PEOZ) and ß-cyclodextrin (ß-CD). The surface functionalization of AuMSS nanospheres led to a size increase and to the neutralization of the surface charge. On the other side, the nanoparticles biological performance was improved. The coated AuMSS nanospheres showed an increased cytocompatibility and internalization rate by the HeLa cancer cells. Overall, the obtained data confirm the successful modification of the AuMSS nanospheres with PEOZ and ß-CD as well as their promising properties for being applied in cancer therapy.
Assuntos
Ouro/química , Nanosferas/química , Neoplasias/terapia , Poliaminas/química , Dióxido de Silício/química , beta-Ciclodextrinas/química , Animais , Movimento Celular , Fibroblastos/citologia , Células HeLa , Hemólise , Humanos , Camundongos , Nanopartículas/química , Nanopartículas/ultraestrutura , Nanosferas/ultraestruturaRESUMO
AIM: Develop a new poly-2-ethyl-2-oxazoline (PEOZ)-based coating for doxorubicin-loaded gold-core mesoporous silica shell (AuMSS) nanorods application in cancer chemo-photothermal therapy. METHODS: PEOZ functionalized AuMSS nanorods were obtained through the chemical grafting on AuMSS of a PEOZ silane derivative. RESULTS: The PEOZ chemical grafting on the surface of AuMSS nanorods allowed the neutralization of nanodevices' surface charge, from -30 to -15 mV, which improved nanoparticles' biocompatibility, namely by decreasing the blood hemolysis to negligible levels. In vitro antitumoral studies revealed that the combined treatment mediated by the PEOZ-coated AuMSS nanorods result in a synergistic effect, allowing the complete eradication of cervical cancer cells. CONCLUSION: The application of the PEOZ coating improves the AuMSS nanorods performance as a multifunctional combinatorial therapy for cervical cancer.