Hdm2 is regulated by K-Ras and mediates p53-independent functions in pancreatic cancer cells.
Oncogene
; 28(5): 709-20, 2009 Feb 05.
Article
en En
| MEDLINE
| ID: mdl-19029954
There is emerging evidence that the oncogenic potential of hdm2 (human and/or murine double minute-2 protein) stems not only from its ability to counteract tumor suppressor p53 but also from its less understood p53-independent functions. Surprisingly, little is known about the role and regulation of hdm2 in pancreatic tumors, a large proportion (50-75%) of which contain mutant p53. In this study, we determined that hdm2 was expressed in a Ras-signaling-dependent manner in various pancreatic cancer cell lines. As p53 was mutated and inactive in these cells, the expression of hdm2 was seemingly redundant. Indeed, the proliferation and survival of cell lines such as Panc-1 and Panc-28 could be inhibited by PRIMA-1 (mutant p53 activator) but not by Nutlin-3 (inhibitor of the hdm2-p53 interaction). Unexpectedly, however, the proliferation of both cell lines was strongly inhibited by hdm2-specific RNAi. Our data also revealed cyclin D1, c-Jun and c-Myc to be novel targets of hdm2 and suggested that they might mediate hdm2's role in cellular proliferation and/or survival. We conclude from our results that hdm2 is expressed in pancreatic cancer cells as a result of activated Ras signaling, and that it regulates cellular proliferation and the expression of three novel target genes by p53-independent mechanisms.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Neoplasias Pancreáticas
/
Regulación Neoplásica de la Expresión Génica
/
Proteína p53 Supresora de Tumor
/
Genes ras
/
Proteínas Proto-Oncogénicas c-mdm2
Límite:
Humans
Idioma:
En
Revista:
Oncogene
Asunto de la revista:
BIOLOGIA MOLECULAR
/
NEOPLASIAS
Año:
2009
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
Reino Unido