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Published on: November 23, 2014
Inducción de la angiogénesis durante la transición de la hiperplasia a la neoplasia
Nature
|May 4, 1989
Resumen
El crecimiento tumoral depende de la angiogénesis. Este estudio encontró que la actividad angiogénica aparece en islotes hiperplásticos antes de la formación de tumores, lo que sugiere que la angiogénesis es clave en la carcinogénesis temprana.
Área de la Ciencia:
- Oncología Oncología.
- Biología del desarrollo Biología del desarrollo.
- Investigación del cáncer Investigación del cáncer.
Sus antecedentes:
- El crecimiento tumoral depende de la angiogénesis, la formación de nuevos vasos sanguíneos.
- El momento preciso y los mecanismos de la transición a un estado angiogénico durante el desarrollo temprano del tumor siguen sin estar claros.
- Los modelos de ratones transgénicos ofrecen una plataforma para estudiar la tumorigénesis en múltiples etapas, incluido el desarrollo temprano del tumor.
Objetivo del estudio:
- Investigar cuándo y cómo surge la actividad angiogénica durante las primeras etapas del desarrollo tumoral.
- Para determinar si la hiperplasia, un aumento en las células normales, precede o requiere la angiogénesis.
- Para correlacionar el inicio de la actividad angiogénica con la posterior incidencia de tumores.
Principales métodos:
- Utilizó ratones transgénicos que expresan un oncogén en las células beta pancreáticas para modelar la tumorigénesis de la normalidad a la neoplasia.
- Actividad angiogénica observada en islotes hiperplásticos in vivo.
- Se empleó un nuevo ensayo in vitro para evaluar el potencial angiogénico de los islotes hiperplásticos independientemente de las condiciones in vivo.
Principales resultados:
- La actividad angiogénica se detectó por primera vez en un subconjunto de islotes hiperplásticos, que preceden a la formación de tumores manifiestos.
- Los ensayos in vitro confirmaron que la hiperplasia por sí sola no induce la angiogénesis.
- La aparición de actividad angiogénica in vitro se correlacionó con la neovascularización in vivo y la posterior incidencia de tumores.
Conclusiones:
- La inducción de la angiogénesis es un evento crítico en la carcinogénesis temprana.
- La angiogénesis no es una consecuencia obligatoria de la hiperplasia, sino más bien un evento específico que ocurre en un subconjunto de lesiones hiperplásticas.
- Los hallazgos proporcionan información sobre el proceso de múltiples pasos del desarrollo tumoral e identifican la angiogénesis como un punto clave de transición.
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