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1.
J Clin Pediatr Dent ; 48(2): 40-46, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38548631

RESUMEN

The aim of this study was to determine whether the relationship between dental age (DA), cervical stage (CS) and chronological age (CA) in Chinese male children with unilateral cleft lip and palate (UCLP) is similar to that of children without clefts. Panoramic and cephalometric radiographs of 105 male UCLP patients, aged from 8 to 16 years, were collected and compared to 210 age-matched healthy control males. The Demirjian and cervical vertebral maturation (CVM) methods were used to visually examine the radiographs and Spearman's correlation analysis was used to identify differences between the two groups with regards to CS, DA and CA. There was a significant positive correlation between DA and CA in both groups and the mean CA-DA difference was significantly higher in children with UCLP when compared to controls (0.319 vs. 0.003, p < 0.05). A significant delay in tooth development was detected in UCLP children from 10 to 12 years-of-age. Both the UCLP and control groups showed high correlations between CS and DA. Calcification stage D appeared only before CS3; however, from CS5 to 6, all teeth have almost completed their maturation phase. Chinese male UCLP patients are likely to experience delayed tooth development compared to healthy controls, especially during the fast-growing period. Evaluating the stages of tooth mineralization could represent a rapid method to assess growth potential.


Asunto(s)
Labio Leporino , Fisura del Paladar , Diente , Niño , Humanos , Masculino , Labio Leporino/diagnóstico por imagen , Fisura del Paladar/diagnóstico por imagen , China
2.
Nanotechnology ; 33(7)2021 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-34749347

RESUMEN

The combination of multiple therapies has been proved to be more effective than a single therapy for many cancers. This study aimed to investigate the synergistic antibreast cancer effect of doxorubicin-loaded silver nanotriangles (DOX-AgNTs) combined with near-infrared (NIR) irradiation and explore the underlying mechanism. AgNTs were prepared by a chemical method and DOX was loaded via electrostatic adsorption. Characterization was performed by transmission electron microscopy, ultraviolet-visible spectroscopy and dynamic light scattering. The viability of MDA-MB-231 cells was detected by using MTT assay to evaluate the synergistic anticancer effect of DOX-AgNTs combined with NIR irradiation. The intracellular reactive oxygen species (ROS) level and cell apoptosis were analyzed by flow cytometry. Mitochondrial membrane potential (MMP) was measured with fluorescence microscopy. The mechanism was further investigated with ROS scavenger N-acetylcysteine and specific inhibitors of extracellular signal-regulated kinase 1/2 (ERK1/2), C-jun N-terminal kinase and p38 pathways. Characterization results revealed that the prepared AgNTs were mostly triangular and the mean edge length was about 126 nm. The combination of DOX-AgNTs and NIR exhibited a superior synergistic anticancer effect over single DOX-AgNTs or photothermal therapy (PTT). N-acetylcysteine and ERK1/2 inhibitor U0126 were found to significantly rescue the decreased cell viability, declined MMP and increased apoptosis induced by the combined treatment. Our results suggested that DOX-AgNTs combined with PTT performed a synergistic antibreast cancer effect. The synergy might be closely associated with the excessive production of ROS, changed MMP and the activation of ERK1/2 signaling pathway. These findings might provide a new perspective for the development of breast cancer treatments with excellent efficacy.


Asunto(s)
Antineoplásicos , Doxorrubicina , Nanopartículas del Metal/química , Terapia Fototérmica , Plata , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacología , Sinergismo Farmacológico , Femenino , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Administración de Fármacos con Nanopartículas , Especies Reactivas de Oxígeno/metabolismo , Plata/química , Plata/farmacología
3.
Nanotechnology ; 32(49)2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34450600

RESUMEN

This study aimed to prepare chitosan-coated silver nanotriangles (AgNTs) and assess their computed tomography (CT) contrast property byin vitroandin vivoexperiments. AgNTs with a range of sizes were synthesized by a seed-based growth method, and subsequently characterized by transmission electron microscopy (TEM), ultraviolet-visible absorption spectroscopy and dynamic light scattering. The x-ray attenuation capability of all prepared AgNTs was evaluated using micro CT. The CT contrast effect of AgNTs with the highest x-ray attenuation coefficient was investigated in MDA-MB-231 breast cancer cells and a mouse model of breast cancer. The TEM results displayed that all synthesized AgNTs were triangular in shape and their mean edge lengths ranged from 60 to 149 nm. All AgNTs tested exhibited stronger x-ray attenuation capability than iohexol at the same mass concentration of the active elements, and the larger the AgNTs size, the higher the x-ray attenuation coefficient. AgNTs with the largest size were selected for further research, due to their strongest x-ray attenuation capability and best biocompatibility. The attenuation coefficient of breast cancer cells treated with AgNTs increased in a particle concentration-dependent manner.In vivoCT imaging showed that the contrast of the tumor injected with AgNTs was significantly enhanced. These findings indicated that AgNTs could be a promising candidate for highly efficient tumor CT contrast agents.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Quitosano/química , Medios de Contraste/química , Plata/química , Animales , Línea Celular Tumoral , Dispersión Dinámica de Luz , Femenino , Humanos , Nanopartículas del Metal/química , Ratones , Microscopía Electrónica de Transmisión , Trasplante de Neoplasias , Tamaño de la Partícula , Microtomografía por Rayos X
4.
Nanotechnology ; 32(14): 145102, 2021 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-33296880

RESUMEN

Radioresistance significantly decreases the efficacy of radiotherapy, which can ultimately lead to tumor recurrence and metastasis. As a novel type of nano-radiosensitizer, silver nanoparticles (AgNPs) have shown promising radiosensitizing properties in the radiotherapy of glioma, but their ability to efficiently enter and accumulate in tumor cells needs to be improved. In the current study, AS1411 and verapamil (VRP) conjugated bovine serum albumin (BSA) coated AgNPs (AgNPs@BSA-AS-VRP) were synthesized and characterized. Dark-field imaging and inductively coupled plasma mass spectrometry were applied to investigate the accumulation of AgNPs@BSA-AS and AgNPs@BSA-AS-VRP mixed in different ratios in U251 glioma cells. To assess the influences of 19:1 mixed AgNPs@BSA-AS and AgNPs@BSA-AS-VRP on the P-glycoprotein (P-gp) efflux activity, rhodamine 123 accumulation assay was carried out. Colony formation assay and tumor-bearing nude mice model were employed to examine the radiosensitizing potential of 19:1 mixed AgNPs@BSA-AS and AgNPs@BSA-AS-VRP. Thioredoxin Reductase (TrxR) Assay Kit was used to detect the TrxR activity in cells treated with different functionally modified AgNPs. Characterization results revealed that AgNPs@BSA-AS-VRP were successfully constructed. When AgNPs@BSA-AS and AgNPs@BSA-AS-VRP were mixed in a ratio of 19:1, the amount of intracellular nanoparticles increased greatly through AS1411-mediated active targeting and inhibition of P-gp activity. In vitro and in vivo experiments clearly showed that the radiosensitization efficacy of 19:1 mixed AgNPs@BSA-AS and AgNPs@BSA-AS-VRP was much stronger than that of AgNPs@BSA and AgNPs@BSA-AS. It was also found that 19:1 mixed AgNPs@BSA-AS and AgNPs@BSA-AS-VRP significantly inhibited intracellular TrxR activity. These results indicate that 19:1 mixed AgNPs@BSA-AS and AgNPs@BSA-AS-VRP can effectively accumulate in tumor cells and have great potential as high-efficiency nano-radiosensitizers in the radiotherapy of glioma.


Asunto(s)
Aptámeros de Nucleótidos/metabolismo , Neoplasias Encefálicas/radioterapia , Glioma/radioterapia , Nanopartículas del Metal/química , Oligodesoxirribonucleótidos/metabolismo , Tolerancia a Radiación , Fármacos Sensibilizantes a Radiaciones/farmacología , Plata/química , Verapamilo/metabolismo , Aptámeros de Nucleótidos/química , Aptámeros de Nucleótidos/farmacología , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Glioma/patología , Humanos , Oligodesoxirribonucleótidos/química , Oligodesoxirribonucleótidos/farmacología , Verapamilo/química , Verapamilo/farmacología
5.
Cell Rep ; 43(6): 114277, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38805397

RESUMEN

Affective empathy enables social mammals to learn and transfer emotion to conspecifics, but an understanding of the neural circuitry and genetics underlying affective empathy is still very limited. Here, using the naive observational fear between cagemates as a paradigm similar to human affective empathy and chemo/optogenetic neuroactivity manipulation in mouse brain, we investigate the roles of multiple brain regions in mouse affective empathy. Remarkably, two neural circuits originating from the ventral hippocampus, previously unknown to function in empathy, are revealed to regulate naive observational fear. One is from ventral hippocampal pyramidal neurons to lateral septum GABAergic neurons, and the other is from ventral hippocampus pyramidal neurons to nucleus accumbens dopamine-receptor-expressing neurons. Furthermore, we identify the naive observational-fear-encoding neurons in the ventral hippocampus. Our findings highlight the potentially diverse regulatory pathways of empathy in social animals, shedding light on the mechanisms underlying empathy circuity and its disorders.


Asunto(s)
Empatía , Hipocampo , Animales , Empatía/fisiología , Hipocampo/fisiología , Hipocampo/metabolismo , Ratones , Masculino , Miedo/fisiología , Ratones Endogámicos C57BL , Neuronas GABAérgicas/metabolismo , Neuronas GABAérgicas/fisiología , Células Piramidales/fisiología , Células Piramidales/metabolismo , Vías Nerviosas/fisiología , Núcleo Accumbens/fisiología
6.
Front Oncol ; 14: 1380793, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38947892

RESUMEN

Glioma is the most common type of primary malignant tumor of the central nervous system (CNS), and is characterized by high malignancy, high recurrence rate and poor survival. Conventional imaging techniques only provide information regarding the anatomical location, morphological characteristics, and enhancement patterns. In contrast, advanced imaging techniques such as dynamic contrast-enhanced (DCE) MRI or DCE CT can reflect tissue microcirculation, including tumor vascular hyperplasia and vessel permeability. Although several studies have used DCE imaging to evaluate gliomas, the results of data analysis using conventional tracer kinetic models (TKMs) such as Tofts or extended-Tofts model (ETM) have been ambiguous. More advanced models such as Brix's conventional two-compartment model (Brix), tissue homogeneity model (TH) and distributed parameter (DP) model have been developed, but their application in clinical trials has been limited. This review attempts to appraise issues on glioma studies using conventional TKMs, such as Tofts or ETM model, highlight advancement of DCE imaging techniques and provides insights on the clinical value of glioma management using more advanced TKMs.

7.
Acad Radiol ; 31(8): 3355-3365, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38443208

RESUMEN

RATIONALE AND OBJECTIVES: Homozygous deletion (HD) of CDKN2A/B holds important prognostic value in gliomas. This study aimed to explore the predictive potential of conventional MRI characteristics combined with dynamic contrast-enhanced MRI parameters in predicting CDKN2A/B HD status in gliomas. MATERIALS AND METHODS: Preoperative MRI data of 105 patients (69 without CDKN2A/B HD, and 36 with CDKN2A/B homozygous deletion) with gliomas were retrospectively collected. Conventional MRI features and dynamic contrast-enhanced-MRI qualitative parameter time-intensity curve type, quantitative parameters Ktrans, Kep, Ve, Vp, and iAUC were obtained. Logistic regression models for prediction of CDKN2A/B HD status were constructed in all types of gliomas and both subtypes of IDH-mutant and IDH-wild gliomas. RESULTS: Multivariate analysis for all patients demonstrated that age (OR=1.103, p = 0.002) and Ktrans (OR=1.051, p < 0.001) independently predicted CDKN2A/B HD. In IDH-mutant subgroup, multivariate analysis results indicated that Ktrans (OR=1.098, p = 0.031) emerged as autonomous predictors of CDKN2A/B HD. In IDH-wild subgroup, age (OR=1.111, p = 0.002) and Ktrans (OR=1.032, p = 0.001) were independent predictors of CDKN2A/B HD according to the multivariate analysis. The areas under the receiver operating characteristic curve of the corresponding models were 0.90, 0.95 and 0.84, respectively. CONCLUSION: Ktrans can serve as valuable predictive parameters for identifying CDKN2A/B HD status in all types of gliomas and both subtypes of IDH-mutant and IDH-wild gliomas. These findings provide a foundation for precise preoperative non-invasive diagnosis and personalized treatment approaches for glioma patients.


Asunto(s)
Neoplasias Encefálicas , Medios de Contraste , Inhibidor p16 de la Quinasa Dependiente de Ciclina , Glioma , Imagen por Resonancia Magnética , Humanos , Glioma/genética , Glioma/diagnóstico por imagen , Femenino , Masculino , Imagen por Resonancia Magnética/métodos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/diagnóstico por imagen , Persona de Mediana Edad , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Adulto , Estudios Retrospectivos , Inhibidor p15 de las Quinasas Dependientes de la Ciclina/genética , Homocigoto , Eliminación de Gen , Anciano , Valor Predictivo de las Pruebas
8.
Front Neurosci ; 18: 1309482, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38435057

RESUMEN

Alzheimer's disease (AD) is a prevalent form of dementia that affects an estimated 32 million individuals globally. Identifying early indicators is vital for screening at-risk populations and implementing timely interventions. At present, there is an urgent need for early and sensitive biomarkers to screen individuals at risk of AD. Among all sensory biomarkers, olfaction is currently one of the most promising indicators for AD. Olfactory dysfunction signifies a decline in the ability to detect, identify, or remember odors. Within the spectrum of AD, impairment in olfactory identification precedes detectable cognitive impairments, including mild cognitive impairment (MCI) and even the stage of subjective cognitive decline (SCD), by several years. Olfactory impairment is closely linked to the clinical symptoms and neuropathological biomarkers of AD, accompanied by significant structural and functional abnormalities in the brain. Olfactory behavior examination can subjectively evaluate the abilities of olfactory identification, threshold, and discrimination. Olfactory functional magnetic resonance imaging (fMRI) can provide a relatively objective assessment of olfactory capabilities, with the potential to become a promising tool for exploring the neural mechanisms of olfactory damage in AD. Here, we provide a timely review of recent literature on the characteristics, neuropathology, and examination of olfactory dysfunction in the AD continuum. We focus on the early changes in olfactory indicators detected by behavioral and fMRI assessments and discuss the potential of these techniques in MCI and preclinical AD. Despite the challenges and limitations of existing research, olfactory dysfunction has demonstrated its value in assessing neurodegenerative diseases and may serve as an early indicator of AD in the future.

9.
Colloids Surf B Biointerfaces ; 211: 112330, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35032851

RESUMEN

Radiotherapy is one of the main treatment modalities for glioma, but the therapeutic efficacy is often limited by the radioresistance of tumor cells. The radiosensitization effects of silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) on tumors have been confirmed by previous studies. To enhance the specific killing effect of irradiation on tumor cells, targeted modification of radiosensitizers is urgently needed. Herein, we developed polyethylene glycol (PEG)-coated Ag@Au core-shell nanoparticles (PSGNPs) modified with GMT8 aptamer (GSGNPs) and evaluated their radiosensitization effects on glioma cells through in vivo and in vitro experiments. Transmission electron microscope image showed that the prepared PSGNPs had a spherical core-shell structure with an average size of 11 nm. The ultraviolet-visible absorption spectra and Fourier transform infrared spectra displayed that GMT8 was successfully conjugated to PSGNPs. The results of dark-field imaging revealed that the targeting ability of GSGNPs to U87 glioma cells was much better than that to normal human microvascular endothelial cells. Additionally, it was also found that the endocytic pathways of GSGNPs mainly involved clathrin-mediated endocytosis and macropinocytosis. The sensitization enhancement ratio of GSGNPs was calculated to be 1.62, which was higher than that of PSGNPs. In vivo imaging results showed that GSGNPs exhibited good tumor targeting and retention capabilities, and the fluorescence intensity ratio of Cy5-GSGNPs to Cy5-PSGNPs reached a peak at 4 h after injection. More importantly, the median survival time of mice bearing U87 glioma was significantly prolonged after intravenous administration of GSGNPs combined with radiotherapy. This work demonstrated that GSGNPs could be used as an effective nano-radiosensitizer for targeted radiotherapy of glioma.


Asunto(s)
Glioma , Nanopartículas del Metal , Animales , Línea Celular Tumoral , Células Endoteliales , Glioma/tratamiento farmacológico , Glioma/patología , Oro/química , Nanopartículas del Metal/química , Ratones , Polietilenglicoles , Plata/química
10.
Nanomedicine (Lond) ; 17(5): 289-302, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35060397

RESUMEN

Aim: To determine the optimal AS1411 density on polyethylene glycol (PEG)ylated silver nanotriangles (PNTs) for targeting breast cancer cells. Methods: PNTs modified with different AS1411 densities (ANTs) were constructed, characterized and evaluated for their targeting properties in breast cancer cells and a mouse model of breast cancer. Results: AS1411 was successfully conjugated to PNTs. The accumulation and cellular uptake of 10-ANTs were the highest. 10-ANTs plus near-IR laser irradiation displayed the greatest inhibitory effect on cell viability. However, 5-ANTs had the highest accumulation in tumor tissues. When combined with NIR laser, 5-ANTs exhibited the best in vivo photothermal therapy effect. Conclusion: The optimal AS1411 densities at the cellular and animal levels were 10% and 5%, respectively.


Asunto(s)
Aptámeros de Nucleótidos , Plata , Animales , Aptámeros de Nucleótidos/farmacología , Línea Celular Tumoral , Humanos , Ratones , Oligodesoxirribonucleótidos , Polietilenglicoles , Plata/farmacología
11.
J Mater Chem B ; 10(33): 6338-6350, 2022 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-35930367

RESUMEN

The issue of pervasively enhanced drug resistance of pancreatic cancer is fundamental to a better understanding of gemcitabine-based chemotherapy. Currently available treatment plans involving injectable therapeutics are mainly engineered to improve the performance and broaden their applications in the domain of biomedicine. Fixed-dose-rate infusion of free gemcitabine (Gem) has drawn appropriate attention for its potent anti-tumor efficacy against various solid tumors, whereas it remains a considerable challenge to extend its application and achieve better treatment. Here, we have prepared and demonstrated a long-acting delivery system using gemcitabine and injectable in situ hydrogel for the localized treatment of pancreatic cancer. The hydrogel was prepared using polysaccharide derivatives, oxidized-carboxymethylcellulose (OCMC) and carboxymethylchitosan (CMCS) at optimal ratios by a dopamine-functionalized method for the controlled release of Gem. In vitro drug release behaviors for up to a week indicated sustained drug release of the Gem delivery system. Moreover, desirable apoptosis promotion and apparent cellular proliferation inhibition associated with the drug depot have been found in vitro against BxPC-3 pancreatic cancer cells, bringing minimized side effects to systemic normal tissues. The current findings manifested that the release out of the localized delivery platform in a sustained pattern afforded a durable gemcitabine-based chemotherapy effect and inhibited tumor metastasis more persistently after intratumoral injection of the Gem@Gel system, thereby advancing the development of novel drug-loaded materials with properties not accessed previously.


Asunto(s)
Hidrogeles , Neoplasias Pancreáticas , Línea Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Humanos , Hidrogeles/uso terapéutico , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/patología , Gemcitabina , Neoplasias Pancreáticas
12.
Nanomedicine (Lond) ; 16(28): 2503-2519, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34812051

RESUMEN

Aim: This study aimed to construct AS1411 and EpDT3-conjugated PEGylated silver nanotriangles (AENTs) and assess their ability to target breast cancer and cancer stem cells, as well as the antitumor and antimetastatic effects of AENT-mediated photothermal therapy. Materials & methods: AENTs were constructed and characterized. The targeting properties, as well as antitumor and antimetastatic activities, were evaluated in MDA-MB-231 breast cancer cells, cancer stem cells and breast cancer-bearing mice. Results: AENTs displayed excellent targeting property to breast cancer cells and cancer stem cells. AENT-mediated photothermal therapy greatly inhibited (>45%) the migration and invasion of breast cancer cells, as well as tumor growth and lung metastasis in the mice. Conclusion: AENT-mediated photothermal therapy might be an effective strategy for the treatment of breast cancer.


Asunto(s)
Neoplasias de la Mama , Plata , Animales , Aptámeros de Nucleótidos , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Línea Celular Tumoral , Femenino , Humanos , Ratones , Células Madre Neoplásicas/patología , Oligodesoxirribonucleótidos , Terapia Fototérmica
13.
Int J Nanomedicine ; 15: 7791-7803, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33116501

RESUMEN

BACKGROUND: The synergistic effect of nanomaterials and chemotherapeutics provides a novel strategy for the treatment of tumors. Silver nanotriangles (AgNTs) exhibited some unique properties in nanomedicine. Studies on the synergy of silver-based nanomaterials and anti-tumor drugs against gliomas are rare. MATERIALS AND METHODS: Chitosan-coated AgNTs were prepared, followed by characterization using transmission electron microscopy, ultraviolet-visible spectroscopy and X-ray diffraction. The anti-glioma effect of cyclophosphamide (CTX), 5-fluorouracil (5-FU), oxaliplatin (OXA), doxorubicin (DOX) or gemcitabine (GEM) combined with AgNTs in different glioma cell lines (U87, U251 and C6) was assessed by the MTT assay to screen out a drug with the most broad-spectrum and strongest synergistic anti-glioma activity. The intracellular reactive oxygen species (ROS) level, mitochondrial membrane potential (MMP) and cell apoptosis were detected by flow cytometry. The possible underlying mechanisms of the synergy were further investigated with ROS scavenger and specific inhibitors of C-jun N-terminal kinase (JNK), p38 and extracellular signal-regulated kinase 1/2 pathways. RESULTS: The synthesized AgNTs were mainly triangular and truncated triangular with an average edge length of 125 nm. A synergistic anti-glioma effect of AgNTs combined with CTX was not observed, and the synergism between AgNTs and 5-FU was cell type-specific. AgNTs combined with OXA, DOX or GEM displayed synergistic effects in various glioma cell lines, and the combination of AgNTs and GEM showed the strongest synergistic activity. A decrease in cell viability, loss of the MMP and an increase in apoptosis rate induced by this synergy could be significantly attenuated by the ROS scavenger N-acetylcysteine and JNK inhibitor SP600125. CONCLUSION: Our results suggested that the combination of AgNTs and GEM possessed broad-spectrum and potent synergistic anti-glioma activity, resulting from cell apoptosis mediated by a ROS-dependent mitochondrial pathway in which JNK might be involved.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Glioma/patología , Mitocondrias/efectos de los fármacos , Nanoestructuras/química , Plata/química , Plata/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Sinergismo Farmacológico , Fluorouracilo/farmacología , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/metabolismo , Especies Reactivas de Oxígeno/metabolismo
14.
Int J Nanomedicine ; 14: 9483-9496, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31819445

RESUMEN

BACKGROUND: The efficacy of radiotherapy for glioma is often limited by the radioresistance of glioma cells. The radiosensitizing effects of silver nanoparticles (AgNPs) on glioma were found in the previous studies of our group. In order to enhance the radiosensitivity of tumor cells and selectively kill them while reducing the side effects of irradiation therapy, targeted modification of AgNPs is urgently needed. MATERIALS AND METHODS: In the present study, AgNPs functionalized with polyethylene glycol (PEG) and aptamer As1411 (AsNPs) were synthesized and subsequently characterized by transmission electron microscopy, ultraviolet-visible spectroscopy and Fourier transform infrared spectroscopy. Then the targeting property of AsNPs was evaluated by dark-field imaging, confocal microscopy and in vivo imaging. Both colony formation assay and glioma-bearing mouse model were employed to study the radiosensitizing effect of AsNPs. RESULTS: The characterization results revealed a spherical shape of AgNPs with an average diameter of 18 nm and the successful construction of AsNPs. AsNPs were confirmed to specifically target C6 glioma cells, but not normal human microvascular endothelial cells. Moreover, AsNPs could not only internalize into tumor cells, but also penetrate into the core of tumor spheroids. In vitro experiments showed that AsNPs exhibited a better radiosensitizing effect than AgNPs and PEGylated AgNPs (PNPs), inducing a higher rate of apoptotic cell death. In vivo imaging demonstrated that Cy5-AsNPs preferentially accumulated at the tumor site, and the ratio of fluorescence intensity of Cy5-AsNPs to that of Cy5-PNPs reached the maximum at 6 h post-systemic administration. Furthermore, the combination of AsNPs with irradiation significantly prolonged the median survival time of C6 glioma-bearing mice. CONCLUSION: Our results indicated that AsNPs could be an effective nano-radiosensitizer for glioma targeting treatment.


Asunto(s)
Aptámeros de Nucleótidos/química , Glioma/radioterapia , Nanopartículas del Metal/química , Oligodesoxirribonucleótidos/química , Polietilenglicoles/química , Fármacos Sensibilizantes a Radiaciones/farmacología , Plata/química , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Modelos Animales de Enfermedad , Células Endoteliales/efectos de los fármacos , Femenino , Glioma/tratamiento farmacológico , Humanos , Hidrodinámica , Nanopartículas del Metal/ultraestructura , Ratones Endogámicos BALB C , Ratones Desnudos , Tamaño de la Partícula , Ratas , Esferoides Celulares/patología , Electricidad Estática , Distribución Tisular
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