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1.
Gene Ther ; 27(1-2): 51-61, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31439890

RESUMEN

Cancer therapies that target a single protein or pathway may be limited by their specificity, thus missing key players that control cellular proliferation and contributing to the failure of the treatment. We propose that approaches to cancer therapy that hit multiple targets would limit the chances of escape. To this end, we have developed a bicistronic adenoviral vector encoding both the CDKN2A and p53 tumor suppressor genes. The bicistronic vector, AdCDKN2A-I-p53, supports the translation of both gene products from a single transcript, assuring that all transduced cells will express both proteins. We show that combined, but not single, gene transfer results in markedly reduced proliferation and increased cell death correlated with reduced levels of phosphorylated pRB, induction of CDKN1A and caspase 3 activity, yet avoiding the induction of senescence. Using isogenic cell lines, we show that these effects were not impeded by the presence of mutant p53. In a mouse model of in situ gene therapy, a single intratumoral treatment with the bicistronic vector conferred markedly inhibited tumor progression while the treatment with either CDKN2A or p53 alone only partially controlled tumor growth. Histologic analysis revealed widespread transduction, yet reduced proliferation and increased cell death was associated only with the simultaneous transfer of CDKN2A and p53. We propose that restoration of two of the most frequently altered genes in human cancer, mediated by AdCDKN2A-I-p53, is beneficial since multiple targets are reached, thus increasing the efficacy of the treatment.


Asunto(s)
Inhibidor p16 de la Quinasa Dependiente de Ciclina/administración & dosificación , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Terapia Genética/métodos , Neoplasias Pulmonares/terapia , Proteína p53 Supresora de Tumor/administración & dosificación , Proteína p53 Supresora de Tumor/genética , Adenoviridae/genética , Animales , Apoptosis/fisiología , Línea Celular Tumoral , Proliferación Celular/fisiología , Inhibidor p16 de la Quinasa Dependiente de Ciclina/biosíntesis , Femenino , Genes p53 , Vectores Genéticos/administración & dosificación , Vectores Genéticos/genética , Células HEK293 , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Transducción Genética/métodos , Proteína p53 Supresora de Tumor/biosíntesis , Ensayos Antitumor por Modelo de Xenoinjerto
3.
Ecotoxicol Environ Saf ; 74(6): 1645-52, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21741708

RESUMEN

The occurrence of visible leaf injury caused by ozone in Ipomoea nil 'Scarlet O'Hara' may be regulated by their redox state, affecting its bioindicator efficiency. Thus, this study aimed to determine whether the redox state of I. nil plants in a subtropical area (São Paulo, SE-Brazil) contaminated by ozone oscillates, and to identify the environmental factors behind these variations. We comparatively evaluated indicators of redox state (ascorbic acid, glutathione, superoxide dismutase, ascorbate peroxidase, glutathione reductase) and leaf injury during nine field experiments of 28 days each. The variations in the redox indicators were explained by the combined effects of chronic levels of ozone and meteorological variables (mainly global solar radiation and air temperature) 3-6 days prior to the sampling days. The ascorbic acid and glutathione were crucial for increasing plant tolerance to ozone. Weak visible injury was observed in all experiments and occurred in leaves with low levels of ascorbic and dehydroascorbic acids.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Ipomoea nil/efectos de los fármacos , Ozono/toxicidad , Ácido Ascórbico/metabolismo , Brasil , Ácido Deshidroascórbico/metabolismo , Glutatión/metabolismo , Glutatión Reductasa/metabolismo , Ipomoea nil/crecimiento & desarrollo , Ipomoea nil/metabolismo , Oxidación-Reducción , Estrés Oxidativo , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Superóxido Dismutasa/metabolismo , Temperatura
4.
Environ Pollut ; 159(2): 458-65, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21093132

RESUMEN

This study intended to determine whether the redox state in plants of Nicotiana tabacum 'Bel-W3' fluctuates in response to the environmental factors in a sub-tropical area contaminated by ozone (São Paulo, SE-Brazil) and which environmental factors are related to this fluctuation, discussing their biomonitoring efficiency. We comparatively evaluated the indicators of redox state (ascorbic acid, glutathione, superoxide dismutase, ascorbate peroxidase, and glutathione reductase) and leaf injury in 17 field experiments performed in 2008. The redox state was explained by the combined effects of chronic levels of O(3) and meteorological variables 4-6 days prior to the plant sampling. Moderate leaf injury was observed in most cases. The redox state of tobacco decreases few days after their placement in the sub-tropical environment, causing them to become susceptible to oxidative stress imposed by chronic doses of O(3). Its bioindicator efficiency would not be diminished in such levels of atmospheric contamination.


Asunto(s)
Contaminantes Atmosféricos/farmacología , Nicotiana/metabolismo , Ozono/farmacología , Ácido Ascórbico/metabolismo , Ecosistema , Glutatión/metabolismo , Glutatión Reductasa/metabolismo , Oxidación-Reducción/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Proteínas de Plantas/metabolismo , Nicotiana/efectos de los fármacos
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