Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 377
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Langmuir ; 36(39): 11637-11644, 2020 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-32902987

RESUMEN

Many noble metal-based nanoparticles have emerged for applications in cancer radiotherapy in recent years, but few investigations have been carried out for palladium nanoparticles. Herein, palladium nanosheets (Pd NSs), which possess a sheetlike morphology with a diameter of ∼14 nm and a thickness of ∼2 nm, were utilized as a sensitizer to improve the performance of radiotherapy. It was found that Pd NSs alone did not decrease the cell viability after treatment for as long as 130 h, suggesting the excellent cytocompatibility of the nanoagents. However, the viability of cancer cells treated with X-ray irradiation became lower, and the viability became even lower if the cells were co-treated with X-ray and Pd NSs, indicating the radiosensitization effect of Pd NSs. Additionally, compared with X-ray irradiation, the combined treatment of Pd NSs and X-ray irradiation induced the generation of more DNA double-stranded breaks and reactive oxygen species within cancer cells, which eventually caused elevated cell apoptosis. Moreover, in vivo experiments also verified the radiosensitization effect and the favorable biocompatibility of Pd NSs, indicating their potential for acquiring satisfactory in vivo radiotherapeutic effect at lower X-ray doses. It is believed that the present research will open new avenues for the application of noble metal-based nanoparticles in radiosensitization.


Asunto(s)
Nanopartículas del Metal , Fármacos Sensibilizantes a Radiaciones , Apoptosis , Supervivencia Celular , Nanopartículas del Metal/toxicidad , Paladio , Fármacos Sensibilizantes a Radiaciones/toxicidad
2.
Int J Mol Sci ; 21(5)2020 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-32120829

RESUMEN

Nanomedicine has stepped into the spotlight of radiation therapy over the last two decades. Nanoparticles (NPs), especially metallic NPs, can potentiate radiotherapy by specific accumulation into tumors, thus enhancing the efficacy while alleviating the toxicity of radiotherapy. Water radiolysis is a simple, fast and environmentally-friendly method to prepare highly controllable metallic nanoparticles in large scale. In this study, we used this method to prepare biocompatible PEGylated (with Poly(Ethylene Glycol) diamine) platinum nanoflowers (Pt NFs). These nanoagents provide unique surface chemistry, which allows functionalization with various molecules such as fluorescent markers, drugs or radionuclides. The Pt NFs were produced with a controlled aggregation of small Pt subunits through a combination of grafted polymers and radiation-induced polymer cross-linking. Confocal microscopy and fluorescence lifetime imaging microscopy revealed that Pt NFs were localized in the cytoplasm of cervical cancer cells (HeLa) but not in the nucleus. Clonogenic assays revealed that Pt NFs amplify the gamma rays induced killing of HeLa cells with a sensitizing enhancement ratio (SER) of 23%, thus making them promising candidates for future cancer radiation therapy. Furthermore, the efficiency of Pt NFs to induce nanoscopic biomolecular damage by interacting with gamma rays, was evaluated using plasmids as molecular probe. These findings show that the Pt NFs are efficient nano-radio-enhancers. Finally, these NFs could be used to improve not only the performances of radiation therapy treatments but also drug delivery and/or diagnosis when functionalized with various molecules.


Asunto(s)
Nanopartículas del Metal/química , Neoplasias/radioterapia , Platino (Metal)/química , Fármacos Sensibilizantes a Radiaciones/farmacología , Muerte Celular , Citoplasma/metabolismo , Células HeLa , Humanos , Nanopartículas del Metal/toxicidad , Nanopartículas del Metal/ultraestructura , Microscopía Electrónica de Transmisión , Tamaño de la Partícula , Polietilenglicoles/química , Polímeros/química , Fármacos Sensibilizantes a Radiaciones/química , Fármacos Sensibilizantes a Radiaciones/toxicidad , Agua/química
3.
Environ Res ; 170: 383-388, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30623885

RESUMEN

PURPOSE: To evaluate if the common field lampricide 3-trifluoromethyl-4-nitrophenol (TFM) that is intended to eradicate the invasive species sea lampreys in the Great Lakes has the potential to sensitize radiation responses in cells from non-targeted native fish MATERIALS AND METHODS: The TFM toxicity was assessed acutely and chronically with the clonogenic fish cell line eelB. The acute toxicity (24-h exposure) was determined by the fluorescent cell viability probe Alamar Blue. The chronic toxicity was determined either by Alamar Blue (7-d exposure) or the clonogenic survival assay (14-d exposure). Pre- and post-exposure of fish cells to environmentally relevant TFM concentrations following gamma irradiation were performed. Clonogenic survival was determined to assess the damage level of radiation-induced reproductive cell death. RESULTS: The chronic toxicity tests were more sensitive than the acute toxicity tests. The 14-d EC50 using the clonogenic survival endpoint was 2.09 ±â€¯0.28 µg/mL and was statistically similar to the 7-d EC50 (1.85 ±â€¯0.07 µg/mL) based on the Alamar Blue-based cytotoxicity endpoint. Post-exposure of cells to environmentally relevant TFM concentrations following irradiation did not have any effect as compared to the irradiation alone group. In contrast, pre-exposure of cells to TFM following irradiation had a negative additive effect when the total radiation dose was 2 Gy, but not 0.1 or 0.5 Gy. CONCLUSION: Our results suggest that the common field lampricide TFM is a potential radiation sensitizer in cells from non-targeted native fish. This could be a health problem of concern for non-targeted native fish if a large accidental radioactive release occurs.


Asunto(s)
Nitrofenoles/toxicidad , Fármacos Sensibilizantes a Radiaciones/toxicidad , Animales , Supervivencia Celular , Peces , Petromyzon/fisiología
4.
J Nanosci Nanotechnol ; 16(5): 4554-60, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27483789

RESUMEN

Adenylate cyclase is a key intracellular enzyme involved in energy imbalance leading to tumor hypoxia and cytotoxicity. In this study, adenylate cyclase activities in isolated hepatocytes and Kupffer cells were compared in the presence of several metabolic stimulators. In cultured hepatocyte cells, adenylate cyclase was stimulated by guanylyl imidotriphosphate (GITP), guanosine triphosphate (GTP), progesterone and nitroimidazole embedded nanoparticle (NNP) effectors, while prostaglandin E2 and F2α were used as effectors in cultured Kupffer cells. The results showed that NNPs decreased adenylate cyclase specific activity in a dose-dependent manner after preincubation of hepatocytes with NNPs. The NNPs stimulated adenylate cyclase activities in hepatocytes were evaluated based on measurement of cyclic adenosine monophosphate (cAMP). The stimulatory effects of NNPs on adenylate cyclase were independent of the presence of GTP and may have been due to a direct effect on the catalytic subunit of adenylate cyclase. In addition, basal cAMP generation in hepatocyte cells was efficiently suppressed by the NNPs. In conclusion, NNPs exerted direct effects on the catalytic subunit of the adenylate cyclase system, and adenylate cyclase was hormone sensitive in liver cells.


Asunto(s)
Adenilil Ciclasas/metabolismo , Hepatocitos/enzimología , Macrófagos del Hígado/enzimología , Nanocápsulas/química , Nitroimidazoles/toxicidad , Hipoxia de la Célula/efectos de los fármacos , Línea Celular , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Hepatocitos/efectos de los fármacos , Hepatocitos/patología , Humanos , Macrófagos del Hígado/efectos de los fármacos , Macrófagos del Hígado/patología , Nanocápsulas/toxicidad , Nanocápsulas/ultraestructura , Fármacos Sensibilizantes a Radiaciones/toxicidad
5.
Pharm Res ; 32(1): 158-66, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25048636

RESUMEN

PURPOSE: Free doxorubicin (DXR) is not currently used to treat brain tumors because (i) the blood-brain barrier limits the drug deposition into the brain (ii) lethal toxic effects occur when combined with radiation therapy. Since encapsulation of DXR within liposomal carriers could overcome these drawbacks, the present study aimed at evaluating the radiosensitizing properties of non-pegylated (NPL-DXR) and pegylated (PL-DXR) liposomal doxorubicin on orthotopic high-grade glioma xenografts (U87). METHODS: DXR accumulation in brain tissues was assessed by a high-performance liquid chromatography method and antitumor efficacy was evaluated by mice survival determination. RESULTS: We showed that encapsulation of DXR ensured a preferential deposition of DXR in tumoral tissue in comparison with normal brain tissue: the best AUC tumor tissue/AUC normal tissue ratio depended greatly on the schedule. Overall, thanks to the optimization of the delivery schedule, we demonstrated a radiosensitizing effect for both liposomal DXR without toxicity of this combination on the U87 human malignant glioma orthotopic xenografts. CONCLUSION: This study shows that the use of nanocarriers, allowing targeting of intracerebral tumor, renders relevant the combination of anthracyclin with radiation therapy to treat brain tumors, opening a new field of therapeutic applications. However, our results point out that, for each new delivery system, the administration schedules need to be rigorously optimized.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Doxorrubicina/análogos & derivados , Glioma/radioterapia , Fármacos Sensibilizantes a Radiaciones/uso terapéutico , Animales , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/metabolismo , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacocinética , Doxorrubicina/uso terapéutico , Doxorrubicina/toxicidad , Esquema de Medicación , Femenino , Glioma/tratamiento farmacológico , Glioma/metabolismo , Humanos , Ratones Desnudos , Clasificación del Tumor , Polietilenglicoles/administración & dosificación , Polietilenglicoles/farmacocinética , Polietilenglicoles/uso terapéutico , Polietilenglicoles/toxicidad , Fármacos Sensibilizantes a Radiaciones/administración & dosificación , Fármacos Sensibilizantes a Radiaciones/farmacocinética , Fármacos Sensibilizantes a Radiaciones/toxicidad , Distribución Tisular , Resultado del Tratamiento , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Proc Natl Acad Sci U S A ; 109(21): 8230-5, 2012 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-22547809

RESUMEN

One of the promises of nanoparticle (NP) carriers is the reformulation of promising therapeutics that have failed clinical development due to pharmacologic challenges. However, current nanomedicine research has been focused on the delivery of established and novel therapeutics. Here we demonstrate proof of the principle of using NPs to revive the clinical potential of abandoned compounds using wortmannin (Wtmn) as a model drug. Wtmn is a potent inhibitor of phosphatidylinositol 3' kinase-related kinases but failed clinical translation due to drug-delivery challenges. We engineered a NP formulation of Wtmn and demonstrated that NP Wtmn has higher solubility and lower toxicity compared with Wtmn. To establish the clinical translation potential of NP Wtmn, we evaluated the therapeutic as a radiosensitizer in vitro and in vivo. NP Wtmn was found to be a potent radiosensitizer and was significantly more effective than the commonly used radiosensitizer cisplatin in vitro in three cancer cell lines. The mechanism of action of NP Wtmn radiosensitization was found to be through the inhibition of DNA-dependent protein kinase phosphorylation. Finally, NP Wtmn was shown to be an effective radiosensitizer in vivo using two murine xenograft models of cancer. Our results demonstrate that NP drug-delivery systems can promote the readoption of abandoned drugs such as Wtmn by overcoming drug-delivery challenges.


Asunto(s)
Androstadienos/farmacocinética , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas , Neoplasias/terapia , Inhibidores de Proteínas Quinasas/farmacocinética , Fármacos Sensibilizantes a Radiaciones/farmacocinética , Androstadienos/toxicidad , Animales , Supervivencia Celular/efectos de los fármacos , Quimioradioterapia/métodos , Células HT29 , Humanos , Células KB , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones SCID , Fosforilación/efectos de los fármacos , Inhibidores de Proteínas Quinasas/toxicidad , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fármacos Sensibilizantes a Radiaciones/toxicidad , Wortmanina , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Zygote ; 22(1): 32-40, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22784634

RESUMEN

Parthenogenetic activation of oocytes is a helpful tool to obtain blastocysts, of which the inner cell mass may be used for derivation of embryonic stem cells. In order to improve activation and embryonic development after parthenogenesis, we tried to use sperm injection and subsequent removal of the sperm head to mimic the natural Ca2+ increases by release of the oocyte activating factor. Visualization of the sperm could be accomplished by Hoechst staining and ultraviolet (UV) light irradiation. To exclude negative effects of this treatment, we examined toxicity on activated mouse oocytes. After activation, oocytes were incubated in Hoechst 33342 or 33258 stain and exposed to UV irradiation. The effects on embryonic development were evaluated. Our results showed that both types of Hoechst combined with UV irradiation have toxic effects on parthenogenetically activated mouse oocytes. Although activation and cleavage rate were not affected, blastocyst formation was significantly reduced. Secondly, we used MitoTracker staining for removal of the sperm. Sperm heads were stained before injection and removed again after 1 h. However, staining was not visible anymore in all oocytes after intracytoplasmic sperm injection. In case the sperm could be removed, most oocytes died after 1 day. As MitoTracker was also not successful, alternative methods for sperm identification should be investigated.


Asunto(s)
Bencimidazoles/toxicidad , Blastocisto/citología , Desarrollo Embrionario/efectos de los fármacos , Desarrollo Embrionario/efectos de la radiación , Oocitos/citología , Partenogénesis/fisiología , Rayos Ultravioleta/efectos adversos , Animales , Blastocisto/efectos de los fármacos , Blastocisto/efectos de la radiación , Células Cultivadas , Femenino , Ratones , Ratones Endogámicos C57BL , Oocitos/efectos de los fármacos , Oocitos/efectos de la radiación , Partenogénesis/efectos de los fármacos , Partenogénesis/efectos de la radiación , Fármacos Sensibilizantes a Radiaciones/toxicidad , Recuperación de la Esperma , Coloración y Etiquetado/métodos
8.
Breast Cancer Res Treat ; 137(1): 81-91, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23160926

RESUMEN

The purpose of this study was to evaluate the effect of molecularly targeted gold nanoparticles (AuNPs) on tumor radiosensitization both in vitro and in vivo. Human Epidermal Growth Factor Receptor-2 (HER-2)-targeted AuNPs (Au-T) were synthesized by conjugating trastuzumab (Herceptin) to 30 nm AuNPs. In vitro, the cytotoxicity of Au-T or non-targeted AuNPs (Au-P) was assessed by γ-H2AX immunofluorescence microscopy for DNA damage and clonogenic survival assays. In vivo, athymic mice bearing subcutaneous MDA-MB-361 xenografts were treated with a single dose of 11 Gy of 100 kVp X-rays 24 h after intratumoral injection of Au-T (~0.8 mg of Au) or no X-radiation. Normal tissue toxicity was determined by hematology or biochemistry parameters. The combination of Au-P or Au-T with X-ray exposure increased the formation of γ-H2AX foci by 1.7 (P = 0.054) and 3.3 (P = 0.024) fold in comparison to X-radiation alone, respectively. The clonogenic survival of cells exposed to Au-T and X-rays was significantly lower from that of cells exposed to X-radiation alone, which translated to a dose enhancement factor of 1.6. In contrast, survival of cells exposed to Au-P and X-rays versus X-radiation alone were not significantly different. In vivo, the combination of Au-T and X-radiation resulted in regression of MDA-MB-361 tumors by 46 % as compared to treatment with X-radiation (16.0 % increase in tumor volume). No significant normal tissue toxicity was observed. Radiosensitization of breast cancer to X-radiation with AuNPs was successfully achieved with an optimized therapeutic strategy of molecular targeting of HER-2 and intratumoral administration.


Asunto(s)
Neoplasias de la Mama/radioterapia , Oro/química , Nanopartículas del Metal/química , Tolerancia a Radiación/efectos de los fármacos , Fármacos Sensibilizantes a Radiaciones/administración & dosificación , Animales , Neoplasias de la Mama/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Roturas del ADN de Doble Cadena , Femenino , Histonas/metabolismo , Humanos , Inyecciones Intralesiones , Ratones , Ratones Desnudos , Terapia Molecular Dirigida , Fármacos Sensibilizantes a Radiaciones/química , Fármacos Sensibilizantes a Radiaciones/toxicidad , Dosificación Radioterapéutica , Receptor ErbB-2/metabolismo , Carga Tumoral/efectos de la radiación , Ensayos Antitumor por Modelo de Xenoinjerto
9.
Nitric Oxide ; 34: 47-55, 2013 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-23623927

RESUMEN

Nitric oxide (NO) is a very effective radiosensitizer of hypoxic mammalian cells, at least as efficient as oxygen in enhancing cell death in vitro. NO may induce cell death through the formation of base lesions which are difficult to repair, and if they occur within complex clustered damage common to ionizing radiation, they may lead to replication-induced DNA strand breaks. It has previously been shown that 8-azaguanine and xanthine result from the reaction of guanine radicals with nitric oxide. We have now shown that adenine radicals also react with NO to form hypoxanthine and 8-azaadenine. Cells irradiated in exponential growth in the presence of NO are twice as radiosensitive compared to those irradiated in anoxia alone, whereas confluent cells are less radiosensitive to (•)NO. In addition, the numbers of DNA double strand breaks observed as γH2AX staining following radiosensitization by NO, are higher in exponential cells than in confluent cells. DNA damage, detected as 53BP1 foci, is also higher in HF-19 cells expressing Cyclin A, a marker for cells in S and G2 phases of the cell cycle, following radiosensitization by NO. RAD51 foci are highest in V79-4 cells irradiated in the presence of NO compared to in anoxia, 24h after radiolysis. This work presents evidence that radiosensitization of cells by NO is in part through the formation of specific DNA damage, difficult to repair, which in dividing cells may induce the formation of stalled replication forks and as a consequence replication-induced DNA strand breaks which may lead to cell death.


Asunto(s)
Daño del ADN , Replicación del ADN/efectos de los fármacos , ADN/efectos de los fármacos , ADN/efectos de la radiación , Óxido Nítrico/toxicidad , Fármacos Sensibilizantes a Radiaciones/toxicidad , Adenina/metabolismo , Animales , Ciclo Celular/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cricetinae , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Recombinasa Rad51/genética , Recombinasa Rad51/metabolismo , Radiación Ionizante
10.
Mutat Res ; 753(1): 42-7, 2013 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-23474391

RESUMEN

Acitretin is currently used alone or combined with PUVA (psoralen + UVA) or with narrow-band ultraviolet B (NBUVB), to treat moderate and severe psoriasis. However, little is known about the potential genotoxic/carcinogenic risk and the cytostatic/cytotoxic effects of these treatments. Our aim was to study the cytotoxic and genotoxic effects of acitretin - alone or in combination with PUVA or NBUVB - by performing studies with blood from patients with psoriasis vulgaris who were treated with acitretin, acitretin+PUVA or acitretin+NBUVB for 12 weeks, and in vitro studies with blood from healthy volunteers, which was incubated with acitretin at different concentrations. The cytotoxic and genotoxic effects were evaluated by the cytokinesis-blocked micronucleus test and the comet assay. Our results show that psoriatic patients treated with acitretin alone or with acitretin+NBUVB, did not show genotoxic effects. In addition, these therapies reduced the rate of proliferation and induced apoptosis and necrosis of lymphocytes; the same occurred with lymphocyte cultures incubated with acitretin (1.2-20µM). The acitretin+PUVA reduced also the proliferation rate, and increased the necrotic lymphocytes. Our studies suggest that therapy with acitretin alone or combined with NBUVB, as used in psoriatic patients, does not show genotoxic effects, reduces the rate of proliferation and induces apoptosis and necrosis of lymphocytes. The combination of acitretin with PUVA also reduces the proliferation rate and increases the number of necrotic lymphocytes. However, as it induced slight genotoxic effects, further studies are needed to clarify its genotoxic potential.


Asunto(s)
Acitretina/toxicidad , Queratolíticos/toxicidad , Linfocitos/efectos de los fármacos , Metoxaleno/toxicidad , Terapia PUVA/efectos adversos , Psoriasis/tratamiento farmacológico , Fármacos Sensibilizantes a Radiaciones/toxicidad , Rayos Ultravioleta/efectos adversos , Acitretina/administración & dosificación , Acitretina/uso terapéutico , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , División Celular/efectos de los fármacos , División Celular/efectos de la radiación , Terapia Combinada , Ensayo Cometa , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Femenino , Humanos , Queratolíticos/administración & dosificación , Queratolíticos/uso terapéutico , Linfocitos/efectos de la radiación , Masculino , Metoxaleno/administración & dosificación , Metoxaleno/uso terapéutico , Pruebas de Micronúcleos , Persona de Mediana Edad , Necrosis , Fármacos Sensibilizantes a Radiaciones/administración & dosificación , Fármacos Sensibilizantes a Radiaciones/uso terapéutico
11.
Int J Mol Sci ; 14(7): 14974-95, 2013 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-23867611

RESUMEN

One of the main goals in radiobiology research is to enhance radiotherapy effectiveness without provoking any increase in toxicity. In this context, it has been proposed that electromagnetic fields (EMFs), known to be modulators of proliferation rate, enhancers of apoptosis and inductors of genotoxicity, might control tumor recruitment and, thus, provide therapeutic benefits. Scientific evidence shows that the effects of ionizing radiation on cellular compartments and functions are strengthened by EMF. Although little is known about the potential role of EMFs in radiotherapy (RT), the radiosensitizing effect of EMFs described in the literature could support their use to improve radiation effectiveness. Thus, we hypothesized that EMF exposure might enhance the ionizing radiation effect on tumor cells, improving the effects of RT. The aim of this paper is to review reports of the effects of EMFs in biological systems and their potential therapeutic benefits in radiotherapy.


Asunto(s)
Campos Electromagnéticos , Neoplasias/radioterapia , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Membrana Celular/efectos de los fármacos , Membrana Celular/efectos de la radiación , Núcleo Celular/efectos de los fármacos , Núcleo Celular/efectos de la radiación , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de la radiación , Radiación Ionizante , Fármacos Sensibilizantes a Radiaciones/uso terapéutico , Fármacos Sensibilizantes a Radiaciones/toxicidad
12.
Photochem Photobiol Sci ; 11(6): 1099-107, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22566080

RESUMEN

The photoprocesses involved in hypericin photoinactivation of three different Candida species (C. albicans, C. parapsilosis and C. krusei) have been examined. Production of singlet oxygen from the triplet state and of superoxide from both the triplet state and the semiquinone radical anion are demonstrated. Hydrogen peroxide is formed downstream of these early events. The outcome of the photodynamic treatments is dictated by the intracellular distribution of hypericin, which is different in the three species and affects the ability of hypericin to produce the different reactive oxygen species and trigger cell-death pathways. The results are in line with the previously-observed different susceptibilities of the three Candida species to hypericin photodynamic treatments.


Asunto(s)
Candida/metabolismo , Perileno/análogos & derivados , Fármacos Sensibilizantes a Radiaciones/toxicidad , Antracenos , Benzoquinonas/metabolismo , Candida/efectos de los fármacos , Candida/efectos de la radiación , Candida albicans/efectos de los fármacos , Candida albicans/metabolismo , Candida albicans/efectos de la radiación , Peróxido de Hidrógeno/metabolismo , Cinética , Luz , Microscopía Fluorescente , Perileno/química , Perileno/toxicidad , Fármacos Sensibilizantes a Radiaciones/química , Oxígeno Singlete/metabolismo
13.
Anticancer Drugs ; 22(8): 732-40, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21562407

RESUMEN

It has been proposed that thioredoxin reductase (TR) is a mediator that allows non-small cell lung cancer (NSCLC) to develop resistance to irradiation; however, little is known regarding the detailed mechanisms of action. Thus, ethaselen {1, 2-[bis (1,2-benzisoselenazolone-3 (2H)-ketone)] ethane, BBSKE}, a novel organoselenium TR inhibitor, is currently being investigated in a phase I clinical trial in China. However, its radiosensitizing effect remains unexplored. In this study, we found that the activity of TR increased dramatically in both A549 and H1299 cells after radiation, and moreover, could be inhibited by pretreatment with BBSKE (5 µmol/l). As a TR inhibitor, BBSKE enhanced the efficacy of radiation therapy both in vivo and in vitro without observable toxicity. BBSKE was found to suppress irradiation-induced NF-κB activation dramatically when using A549 cells stably transfected with NF-κB luciferase reporter. These results show the critical role of TR in the radioresistance of NSCLC and suggest that BBSKE is a potentially promising agent for the treatment of patients with NSCLC clinically.


Asunto(s)
Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Compuestos de Organoselenio/farmacología , Fármacos Sensibilizantes a Radiaciones/farmacología , Animales , Compuestos Bicíclicos Heterocíclicos con Puentes/toxicidad , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Línea Celular Tumoral , Genes Reporteros , Humanos , Luciferasas/genética , Neoplasias Pulmonares/radioterapia , Masculino , Ratones , Ratones Endogámicos C57BL , FN-kappa B/efectos de los fármacos , FN-kappa B/metabolismo , FN-kappa B/efectos de la radiación , Compuestos de Organoselenio/toxicidad , Tolerancia a Radiación , Fármacos Sensibilizantes a Radiaciones/toxicidad , Reductasa de Tiorredoxina-Disulfuro/antagonistas & inhibidores , Transfección
14.
Bioorg Med Chem Lett ; 21(4): 1151-4, 2011 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-21251826

RESUMEN

This Letter describes the novel radiosensitizing agents based on nucleoside base modification. In addition to the known 5-phenylselenide derivative, 5-methylselenide modified thymidine, which has a van der Waals radius smaller than the phenyl group, was newly synthesized. The similar monomer activity of 5-methylselenide derivative under oxidation condition was confirmed by NMR experiments. The cytotoxicity tests and radiosensitizing experiments of both compounds were carried out using the H460 lung cancer cell line. Both the 5-phenylselenide and the 5-methylselenide derivatives showed a relatively low toxicity to the cells. However, in combination with γ-radiolysis, both exerted good radiosensitizing effects to the lung cancer cell lines in vitro. This result confirms that 5-methylselenide modified thymidine could be a useful candidate as a potential radiosensitizing agent in vivo.


Asunto(s)
Desoxiuridina/análogos & derivados , Compuestos de Organoselenio/química , Fármacos Sensibilizantes a Radiaciones/química , Línea Celular Tumoral , Desoxiuridina/síntesis química , Desoxiuridina/química , Desoxiuridina/toxicidad , Rayos gamma , Humanos , Espectroscopía de Resonancia Magnética , Compuestos de Organoselenio/síntesis química , Compuestos de Organoselenio/toxicidad , Oxidación-Reducción , Fármacos Sensibilizantes a Radiaciones/síntesis química , Fármacos Sensibilizantes a Radiaciones/toxicidad
15.
ACS Appl Mater Interfaces ; 13(24): 27934-27944, 2021 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-34101408

RESUMEN

Due to conventional photodynamic therapy encountering serious problems of phototoxicity and low tissue-penetrating depth of light, other dynamic therapy-based therapeutic methods such as sonodynamic therapy (SDT) are expected to be developed. To improve the therapeutic response to SDT, more effective sonosensitizers are imperative. In this study, a novel water-soluble iridium(III)-porphyrin sonosensitizer (IrTMPPS) was synthesized and used for SDT. IrTMPPS generated ample singlet oxygen (1O2) under US irradiation and especially showed distinguished US-activatable abilities at more than 10 cm deep-tissue depths. Interestingly, under US irradiation, IrTMPPS sonocatalytically oxidized intracellular NADH, which would enhance SDT efficiency by breaking the redox balance in the tumor. Moreover, IrTMPPS displayed great sonocytotoxicity toward various cancer cells, and in vivo experiments demonstrated efficient tumor inhibition and anti-metastasis to the lungs in the presence of IrTMPPS and US irradiation. This report gives a novel idea of metal-based sonosensitizers for sonotherapy by fully taking advantage of non-invasiveness, water solubility, and deep tumor therapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias/tratamiento farmacológico , Porfirinas/uso terapéutico , Fármacos Sensibilizantes a Radiaciones/uso terapéutico , Animales , Antineoplásicos/síntesis química , Antineoplásicos/toxicidad , Línea Celular Tumoral , Iridio/química , Iridio/uso terapéutico , Iridio/toxicidad , Ratones , NAD/química , NAD/metabolismo , Neoplasias/patología , Oxidación-Reducción , Porfirinas/síntesis química , Porfirinas/toxicidad , Fármacos Sensibilizantes a Radiaciones/síntesis química , Fármacos Sensibilizantes a Radiaciones/toxicidad , Oxígeno Singlete/metabolismo , Ondas Ultrasónicas , Pez Cebra
16.
ACS Appl Mater Interfaces ; 13(36): 42473-42485, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34474563

RESUMEN

The particular characteristics of hypoxia, immune suppression in the tumor microenvironment, and the lack of accurate imaging guidance lead to the limited effects of stereotactic body radiotherapy (SBRT) in reducing the recurrence rate and mortality of hepatocellular carcinoma (HCC). This research developed a novel theranostic agent based on Bi/Se nanoparticles (NPs), synthesized by a simple reduction reaction method for in vivo CT image-guided SBRT sensitization in mice. After loading Lenvatinib (Len), the obtained Bi/Se-Len NPs had excellent performance in reversing hypoxia and the immune suppression status of HCC. In vivo CT imaging results uncovered that the radiotherapy (RT) area could be accurately labeled after the injection of Bi/Se-Len NPs. Under Len's unique and robust properties, in vivo treatment was then carried out upon injection of Bi/Se-Len NPs, achieving excellent RT sensitization effects in a mouse HCC model. Comprehensive tests and histological stains revealed that Bi/Se-Len NPs could reshape and normalize tumor blood vessels, reduce the hypoxic situation of the tumor, and upregulate tumor-infiltrating CD4+ and CD8+ T lymphocytes around the tumors. Our work highlights an excellent proposal of Bi/Se-Len NPs as theranostic nanoparticles for image-guided HCC radiotherapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Medios de Contraste/uso terapéutico , Neoplasias Hepáticas/tratamiento farmacológico , Nanopartículas del Metal/uso terapéutico , Microambiente Tumoral/efectos de los fármacos , Animales , Bismuto/química , Bismuto/uso terapéutico , Bismuto/toxicidad , Vasos Sanguíneos/efectos de los fármacos , Carcinoma Hepatocelular/diagnóstico por imagen , Línea Celular Tumoral , Medios de Contraste/síntesis química , Medios de Contraste/toxicidad , Portadores de Fármacos/síntesis química , Portadores de Fármacos/uso terapéutico , Portadores de Fármacos/toxicidad , Femenino , Humanos , Hipoxia/tratamiento farmacológico , Neoplasias Hepáticas/diagnóstico por imagen , Linfocitos/efectos de los fármacos , Nanopartículas del Metal/química , Nanopartículas del Metal/toxicidad , Ratones Endogámicos BALB C , Compuestos de Fenilurea/uso terapéutico , Medicina de Precisión , Puntos Cuánticos/química , Puntos Cuánticos/uso terapéutico , Puntos Cuánticos/toxicidad , Quinolinas/uso terapéutico , Fármacos Sensibilizantes a Radiaciones/síntesis química , Fármacos Sensibilizantes a Radiaciones/uso terapéutico , Fármacos Sensibilizantes a Radiaciones/toxicidad , Radiocirugia , Selenio/química , Selenio/uso terapéutico , Selenio/toxicidad , Tomografía Computarizada por Rayos X
17.
Bioorg Med Chem Lett ; 20(2): 600-2, 2010 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-20005706

RESUMEN

A series of (Z)-5-((N-benzyl-1H-indol-3-yl)methylene)imidazolidine-2,4-dione (9a-9m) and 5-((N-benzyl-1H-indol-3-yl)methylene)pyrimidine-2,4,6(1H,3H,5H)-trione (10a-10i) derivatives that incorporate a variety of aromatic substituents in both the indole and N-benzyl moieties have been synthesized. These analogs were evaluated for their radiosensitization activity against the HT-29 cell line. Three analogs, 10a, 10b, and 10c were identified as the most potent radiosensitizing agents.


Asunto(s)
Antineoplásicos/química , Barbitúricos/química , Indoles/química , Pirimidinas/química , Fármacos Sensibilizantes a Radiaciones/química , Antineoplásicos/síntesis química , Antineoplásicos/toxicidad , Barbitúricos/síntesis química , Barbitúricos/toxicidad , Benceno/química , Células HT29 , Humanos , Indoles/síntesis química , Indoles/toxicidad , Pirimidinas/síntesis química , Pirimidinas/toxicidad , Fármacos Sensibilizantes a Radiaciones/síntesis química , Fármacos Sensibilizantes a Radiaciones/toxicidad
18.
J Photochem Photobiol B ; 205: 111820, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32065959

RESUMEN

Recent studies focus on usage of blue light of λ = 450 nm in combination with photosensitizers to treat surface skin disorders, including cancers. In search of convenient therapeutic factor we studied riboflavin analogue 3-methyl-tetraacetylriboflavin (3MeTARF) as potential sensitizer. Riboflavin (Rfl) itself, non -toxic in the darkness, upon absorption of UVA and blue light, may act as photosensitizer. However, Rfl efficiency is limited due to its susceptibility to photodecomposition. Riboflavin's acetylated analogue, 3MeTARF, bears substituents in ribose chain, which inhibit intramolecular processes leading to degradation. Upon excitation, this compound, reveals higher photochemical resistance, remaining a good singlet oxygen generator. Thus, being more stable as the sensitizer, might be much more efficient in photodynamic processes. The objective of undertaken study was to elucidate mechanisms of 3MeTARF photoreactivity under the irradiation with blue light in comparison to its mater compound, riboflavin. We approached this goal by using spectroscopic methods, like direct singlet oxygen phosphorescence detection at 1270 nm, EPR spin trapping and oximetry. Additionally, we tested both riboflavin and 3MeTARF phototoxicity against melanoma cells (WM115) and we studied mechanism of photodynamic cell death, as well. Moreover, 3MeTARF induces apoptosis in melanoma cells at ten times lower concentration than riboflavin itself. Our studies confirmed that 3MeTARF remains stable upon blue light activation and is more efficient photosensitizer than Rfl.


Asunto(s)
Fármacos Sensibilizantes a Radiaciones , Riboflavina , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Dermatitis Fototóxica , Humanos , Peróxido de Hidrógeno/metabolismo , Luz , Fármacos Sensibilizantes a Radiaciones/química , Fármacos Sensibilizantes a Radiaciones/efectos de la radiación , Fármacos Sensibilizantes a Radiaciones/toxicidad , Riboflavina/análogos & derivados , Riboflavina/química , Riboflavina/efectos de la radiación , Riboflavina/toxicidad , Oxígeno Singlete/química
19.
Biochem Pharmacol ; 182: 114205, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32828802

RESUMEN

A continuous state of oxidative stress during inflammation contributes to the development of 25% of human cancers. Epithelial and inflammatory cells release reactive oxygen species (ROS) and reactive nitrogen species (RNS) that can damage DNA. ROS/RNS have biological implications in both chemoresistance and tumor recurrence. As several clinically employed anticancer drugs can generate ROS/RNS, we have addressed herein how inducible nitric oxide synthase and nitric oxide (iNOS/•NO) affect the molecular pathways implicated in the tumor response to oxidative stress. To mimic the oxidative stress associated with chemotherapy, we used a photosensitizer (pheophorbide a) that can generate ROS/RNS in a controlled manner. We investigated how iNOS/•NO modulates the tumor response to oxidative stress by involving the NF-κB and Nrf2 molecular pathways. We found that low levels of iNOS induce the development of a more aggressive tumor population, leading to survival, recurrence and resistance. By contrast, high levels of iNOS/•NO sensitize tumor cells to oxidative treatment, causing cell growth arrest. Our analysis showed that NF-κB and Nrf2, which are activated in response to oxidative stress, communicate with each other through RKIP. For this critical role, RKIP could be an interesting target for anticancer drugs. Our study provides insight into the complex signaling response of cancer cells to oxidative treatments as well as new possibilities for the rational design of new therapeutic strategies.


Asunto(s)
Óxido Nítrico/fisiología , Estrés Oxidativo/fisiología , Neoplasias de la Próstata/metabolismo , Fármacos Sensibilizantes a Radiaciones/toxicidad , Especies Reactivas de Oxígeno/metabolismo , Línea Celular Tumoral , Clorofila/análogos & derivados , Clorofila/toxicidad , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Humanos , Masculino , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/efectos de la radiación , Óxido Nítrico Sintasa de Tipo II/metabolismo , Óxido Nítrico Sintasa de Tipo II/efectos de la radiación , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/efectos de la radiación , Neoplasias de la Próstata/patología , Especies Reactivas de Oxígeno/efectos de la radiación
20.
Cancer Prev Res (Phila) ; 13(6): 551-562, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32161072

RESUMEN

Sulforaphane (SFN), a potent antioxidant and antiinflammatory agent, has been shown to protect against cancers especially at early stages. However, how SFN affects UVB-mediated epigenome/DNA methylome and transcriptome changes in skin photodamage has not been fully assessed. Herein, we investigated the transcriptomic and DNA methylomic changes during tumor initiation, promotion, and progression and its impact and reversal by SFN using next-generation sequencing (NGS) technology. The results show that SFN reduced tumor incidence and tumor number. SFN's protective effects were more dramatic in the early stages than with later stages. Bioinformatic analysis of RNA sequencing (RNA-seq) data shows differential expressed genes and identifies the top canonical pathways related to SFN treatment of UVB-induced different stages of epidermal carcinogenesis. These pathways include p53 signaling, cell cycle: G2-M DNA damage checkpoint regulation, Th1, and Th2 activation pathway, and PTEN signaling pathways. The top upstream regulators related to UVB and SFN treatment as time progressed include dextran sulfate, TP53, NFE2L2 (Nrf2), IFNB1, and IL10RA. Bioinformatic analysis of Methyl-seq data shows several differential methylation regions induced by UVB were attenuated by SFN. These include Notch1, Smad6, Gnai3, and Apc2 Integrative analysis of RNA-seq and DNA-seq/CpG methylome yields a subgroup of genes associated with ultraviolet B (UVB) and SFN treatment. The changes in gene expression were inversely correlated with promoter CpG methylation status. These genes include Pik3cd, Matk, and Adm2 In conclusion, our study provides novel insights on the impact of SFN on the transcriptomic and DNA methylomic of UVB-induced different stages of skin cancer in mice.


Asunto(s)
Anticarcinógenos/uso terapéutico , Metilación de ADN/efectos de los fármacos , Epigenoma/efectos de los fármacos , Isotiocianatos/uso terapéutico , Neoplasias Inducidas por Radiación/prevención & control , Neoplasias Cutáneas/prevención & control , Sulfóxidos/uso terapéutico , Transcriptoma/efectos de los fármacos , Rayos Ultravioleta/efectos adversos , Acetona/toxicidad , Animales , Islas de CpG/efectos de los fármacos , ADN de Neoplasias/genética , Progresión de la Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Ratones , Ratones Pelados , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Neoplasias Inducidas por Radiación/etiología , Neoplasias Inducidas por Radiación/genética , Regiones Promotoras Genéticas , ARN Mensajero/biosíntesis , ARN Mensajero/genética , ARN Neoplásico/biosíntesis , ARN Neoplásico/genética , RNA-Seq , Fármacos Sensibilizantes a Radiaciones/toxicidad , Distribución Aleatoria , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA