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06:51
Techniques to Induce and Quantify Cellular Senescence
Published on: May 1, 2017
BRAFE600-asociado con la senescencia-como la detención del ciclo celular de la nave humana
Chrysiis Michaloglou1, Liesbeth C W Vredeveld, Maria S Soengas
1Division of Molecular Genetics, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands.
Nature
|August 5, 2005
Resumen
La senescencia inducida por oncogenes, impulsada por las mutaciones BRAF (V600E) en los melanocitos, actúa como un mecanismo protector que previene el crecimiento tumoral. Este estudio confirma que la senescencia inducida por oncogenes es un proceso fisiológico, observado en la piel humana.
Área de la Ciencia:
- La senescencia celular es senescencia celular.
- La detención del ciclo celular inducida por oncogenes.
- Los mecanismos supresores de tumores son los mecanismos supresores de tumores.
Sus antecedentes:
- Las células normales de los mamíferos tienen una vida útil limitada, un proceso llamado senescencia, que impide la proliferación incontrolada.
- La senescencia generalmente se desencadena por el desgaste de los telómeros y los supresores de tumores como p16 ((INK4a).
- El papel fisiológico de la senescencia inducida por oncogenes ha sido objeto de debate, particularmente en tumores benignos.
Objetivo del estudio:
- Investigar si la senescencia inducida por BRAF (V600E) ocurre en melanocitos humanos dentro de naevi.
- Para determinar si la senescencia inducida por oncogenes es un auténtico mecanismo de protección fisiológica.
Principales métodos:
- Expresión sostenida de BRAF ((V600E) en melanocitos humanos in vitro.
- Análisis de la inducción de p16 ((INK4a) y la actividad de la beta-galactosidasa (SA-beta-Gal) asociada a la senescencia.
- Validación in vivo con el uso de biopsias congénitas de naevi.
Principales resultados:
- BRAF ((V600E) expresión inducida por la detención del ciclo celular, p16 ((INK4a) inducción, y la actividad de SA-beta-Gal en los melanocitos.
- El naevi congénito mostró una actividad consistente de SA-beta-Gal, lo que confirma la senescencia in vivo.
- Naevi no exhibió desgaste de los telómeros, lo que apoya un proceso activo de senescencia impulsado por oncogenes.
Conclusiones:
- Los melanocitos que expresan BRAF ((V600E) en los naevi muestran signos de senescencia.
- La senescencia inducida por oncogenes es un proceso fisiológico que actúa como una barrera contra la progresión tumoral.
- Este mecanismo de senescencia protege contra la proliferación impulsada por BRAF (V600E) en las lesiones melanocíticas.
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