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Errores de segregación cromosómica como causa de daño en el ADN y aberraciones cromosómicas estructurales
Aniek Janssen1, Marja van der Burg, Karoly Szuhai
1Department of Medical Oncology and Cancer Genomics Center, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG, Utrecht, Netherlands.
Science (New York, N.Y.)
|October 1, 2011
Resumen
Los errores de segregación cromosómica durante la división celular pueden conducir a aberraciones cromosómicas estructurales, como translocaciones, al dañar los cromosomas mal segregados. Este hallazgo vincula la inestabilidad de cromosomas enteros con el desarrollo de cáncer.
Área de la Ciencia:
- Genética La genética.
- Biología Molecular Biología Molecular
- Investigación del cáncer Investigación del cáncer.
Sus antecedentes:
- Las aberraciones cromosómicas, incluidas las numéricas (aneuploidía) y estructurales (translocaciones, deleciones), son características de los tumores humanos y impulsan la tumorigénesis.
- La aneuploidía surge de errores en la segregación cromosómica durante la mitosis.
- Las aberraciones estructurales suelen ser el resultado de roturas de ADN no reparadas.
Objetivo del estudio:
- Para investigar si los errores de segregación cromosómica pueden causar directamente las aberraciones cromosómicas estructurales.
- Aclarar los mecanismos moleculares que vinculan la desagregación cromosómica con el daño estructural.
Principales métodos:
- Análisis de cromosomas mal segregados durante la citoquinesis.
- Detección de las vías de respuesta de ruptura de doble cadena de ADN (ATM, Chk2, p53) en células hijas.
- Evaluación de las translocaciones resultantes en células hijas.
Principales resultados:
- Los cromosomas mal segregados se dañan con frecuencia durante la citoquinesis.
- Este daño desencadena una respuesta de ruptura de doble cadena de ADN que involucra a ATM, Chk2 y p53.
- Estas rupturas de doble hebra pueden conducir a translocaciones desequilibradas en las células hijas.
Conclusiones:
- Los errores de segregación cromosómica son una causa directa de las aberraciones cromosómicas estructurales, específicamente las translocaciones.
- Esto proporciona un nuevo mecanismo que vincula la inestabilidad del cromosoma entero con el desarrollo del cáncer.
- Comprender esta vía ofrece nuevos conocimientos sobre la tumorigénesis y posibles objetivos terapéuticos.
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