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1.
Arch Biochem Biophys ; 687: 108384, 2020 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-32343974

RESUMEN

Epithelial mesenchymal transition (EMT) is a well-known and important step in metastasis and thus can be a key target in cancer treatment. Here, we tested the EMT inhibitory actions of Selaginella tamariscina and its active component, amentoflavone (AF). EMT was examined in vitro using wound-healing and invasion assays and by monitoring changes in the expression of the EMT-related proteins, E-cadherin, Snail, and Twist. Metastasis was examined in vivo using SCID mice injected with luciferase-labeled A549 cells. We confirmed that aqueous extracts of S. tamariscina (STE) and AF inhibited EMT in human cancer cell lines. We found that STE and AF at nontoxic concentrations exerted remarkable inhibitory effects on migration (wound healing assay) and invasion (Transwell assay) in tumor necrosis factor (TGF)-ß-treated cancer cells. Western blotting and immunofluorescence imaging show that AF treatment also restored E-cadherin expression in these cells compared to cells treated with TGF-ß only. Suppression of metastasis by AF was investigated by monitoring migration of tail-vein-injected, circulating A549-luc cells to the lungs in mice. After 3 wk, fewer nodules were observed in mice co-treated with AF compared with those treated with TGF-ß only. Our findings indicate that STE and AF are promising EMT inhibitors and, ultimately, potentially potent antitumor agents.


Asunto(s)
Antineoplásicos/uso terapéutico , Biflavonoides/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Metástasis de la Neoplasia/prevención & control , Selaginellaceae/química , Células A549 , Animales , Antígenos CD/metabolismo , Antineoplásicos/farmacología , Biflavonoides/farmacología , Cadherinas/metabolismo , Movimiento Celular/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Humanos , Ratones SCID , Proteínas Nucleares/metabolismo , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Factores de Transcripción de la Familia Snail/metabolismo , Factor de Crecimiento Transformador beta/farmacología , Proteína 1 Relacionada con Twist/metabolismo
2.
Int J Pharm ; 580: 119237, 2020 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-32201251

RESUMEN

Hypoxia is a characteristic feature of various ischemic diseases, including cancer. This study describes the development of glycol chitosan nanoparticles, hydrophobically modified with 4-nitrobenzyl chloroformate and folic acid (FA), that can specifically release drugs under hypoxic conditions. This hypoxia-responsive glycol chitosan nanoparticle conjugated with FA (HRGF) possesses tumor-targeting properties by virtue of conjugated FA and is able to release drugs in a nitroreductase (NTR)-dependent manner because its structure is cleaved by NTR under hypoxic conditions. HRGF nanoparticles showed improved in vivo cancer-targeting ability compared with HRG nanoparticles without FA. In vitro drug release profiles revealed that doxorubicin (DOX)-loaded HRGF (D@HRGF) nanoparticles showed rapid release under hypoxia conditions than normoxic conditions. In vitro cytotoxicity tests and microscopic observations showed that D@HRGF nanoparticles were more toxic towards hypoxic cells than normoxic cells, and that the release of DOX was more effective in hypoxia than normoxia. In vivo, D@HRGF nanoparticles showed more effective antitumor activity in mice compared with D@HRG and free DOX. Collectively, these results show that HRGF nanoparticles function as an effective drug-delivery system in hypoxic conditions. Moreover, these hypoxia-responsive nanoparticles would be effective not only in cancer, but also in other ischemic diseases.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Quitosano/química , Ácido Fólico/química , Hipoxia/tratamiento farmacológico , Nanopartículas/química , Células A549 , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Doxorrubicina/farmacología , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos/efectos de los fármacos , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Células MCF-7 , Ratones , Polietilenglicoles/química
3.
Biochem Biophys Res Commun ; 524(2): 346-353, 2020 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-32000999

RESUMEN

Recent developments in tissue clearing methods such as CLARITY (Clear Lipid-exchanged Acrylamide-hybridized Rigid Imaging/Immunostaining/In situ hybridization-compatible Tissue hYdrogel) have allowed for the three-dimensional analysis of biological structures in whole, intact tissue, providing greater understanding of spatial relationships and biological circuits. Nonetheless, studies have reported issues with maintaining structural integrity and preventing tissue disintegration, preventing the wide application of these techniques to fragile tissues such as developing embryos. Here, we present optimized passive clearing techniques, mPACT-A, that improve tissue rigidity without the expense of optical transparency. We also present a further modified mPACT-A protocol that is specifically optimized for handling mouse embryos, which are small and fragile, such that they easily dismantle when processed via established tissue clearing methods. We demonstrate proof-of-concept by investigating the expression of two relatively understudied PRDM proteins, PRDM7 and PRDM12, in intact cleared mouse embryos at various stages of development. We observed strong PRDM7 and PRDM12 expression in the developing mouse nervous system, suggestive of potential roles in neural development that will be tested in future functional studies.


Asunto(s)
Proteínas Portadoras/genética , Regulación del Desarrollo de la Expresión Génica , Ratones/embriología , Proteínas del Tejido Nervioso/genética , Animales , Proteínas Portadoras/análisis , Desarrollo Embrionario , Femenino , Imagenología Tridimensional , Inmunohistoquímica , Hibridación in Situ , Ratones/genética , Ratones Endogámicos BALB C , Proteínas del Tejido Nervioso/análisis
4.
J Foot Ankle Surg ; 52(5): 678-80, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23790407

RESUMEN

Neurothekeoma is a rare, benign, cutaneous tumor of nerve sheath origin that is also termed benign nerve sheath myxoma. This tumor is usually asymptomatic and grows slowly. Neurothekeoma is typically found in young adults and seldom occurs in children. It is most commonly located in the head, neck, and upper extremity and extremely rarely found in the lower leg. We report a rare case of ankle neurothekeoma in a child, with a review of the related published data.


Asunto(s)
Tobillo , Neurotecoma/patología , Neoplasias Cutáneas/patología , Niño , Femenino , Humanos , Neurotecoma/cirugía , Neoplasias Cutáneas/cirugía
5.
J Am Chem Soc ; 129(42): 12739-45, 2007 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-17892287

RESUMEN

We report the fabrication and characterization of thermally cross-linked superparamagnetic iron oxide nanoparticles (TCL-SPION) and their application to the dual imaging of cancer in vivo. Unlike dextran-coated cross-linked iron oxide nanoparticles, which are prepared by a chemical cross-linking method, TCL-SPION are prepared by a simple, thermal cross-linking method using a Si-OH-containing copolymer. The copolymer, poly(3-(trimethoxysilyl)propyl methacrylate-r-PEG methyl ether methacrylate-r-N-acryloxysuccinimide), was synthesized by radical polymerization and used as a coating material for as-synthesized magnetite (Fe3O4) SPION. The polymer-coated SPION was further heated at 80 degrees C to induce cross-linking between the -Si(OH)3 groups in the polymer chains, which finally generated TCL-SPION bearing a carboxyl group as a surface functional group. The particle size, surface charge, presence of polymer-coating layers, and the extent of thermal cross-linking were characterized and confirmed by various measurements, including dynamic light scattering, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The carboxyl TCL-SPION was converted to amine-modified TCL-SPION and then finally to Cy5.5 dye-conjugated TCL-SPION for use in dual (magnetic resonance/optical) in vivo cancer imaging. When the Cy5.5 TCL-SPION was administered to Lewis lung carcinoma tumor allograft mice by intravenous injection, the tumor was unambiguously detected in T2-weighted magnetic resonance images as a 68% signal drop as well as in optical fluorescence images within 4 h, indicating a high level of accumulation of the nanomagnets within the tumor site. In addition, ex vivo fluorescence images of the harvested tumor and other major organs further confirmed the highest accumulation of the Cy5.5 TCL-SPION within the tumor. It is noteworthy that, despite the fact that TCL-SPION does not bear any targeting ligands on its surface, it was highly effective for tumor detection in vivo by dual imaging.


Asunto(s)
Compuestos Férricos/química , Neoplasias/diagnóstico , Animales , Carbocianinas/farmacología , Reactivos de Enlaces Cruzados/farmacología , Electrones , Humanos , Ratones , Nanopartículas/química , Nanotecnología/métodos , Neoplasias/metabolismo , Sondas de Oligonucleótidos/farmacología , Polietilenglicoles/química , Dispersión de Radiación , Espectrometría por Rayos X , Temperatura
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