Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Selective inactivation of p53 facilitates mouse epithelial tumor progression without chromosomal instability
Autore:
Lu, XD; Magrane, G; Yin, CY; Louis, DN; Gray, J; Van Dyke, T;
Indirizzi:
Univ N Carolina, Dept Biochem & Biophys, Chapel Hill, NC 27599 USA Univ N Carolina Chapel Hill NC USA 27599 ophys, Chapel Hill, NC 27599 USA Univ Calif San Francisco, Dept Lab Med, San Francisco, CA 94143 USA Univ Calif San Francisco San Francisco CA USA 94143 ancisco, CA 94143 USA Harvard Univ, Massachusetts Gen Hosp, Sch Med, Mol Neurooncol Lab, Charlestown, MA 02129 USA Harvard Univ Charlestown MA USA 02129 ncol Lab, Charlestown, MA 02129 USA
Titolo Testata:
MOLECULAR AND CELLULAR BIOLOGY
fascicolo: 17, volume: 21, anno: 2001,
pagine: 6017 - 6030
SICI:
0270-7306(200109)21:17<6017:SIOPFM>2.0.ZU;2-2
Fonte:
ISI
Lingua:
ENG
Soggetto:
WILD-TYPE P53; CELL-CYCLE CONTROL; COMPARATIVE GENOMIC HYBRIDIZATION; TRANSGENIC MICE; P53-DEFICIENT MICE; GENE AMPLIFICATION; SUPPRESSOR GENE; POINT MUTATIONS; APOPTOSIS; CHECKPOINT;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Life Sciences
Citazioni:
75
Recensione:
Indirizzi per estratti:
Indirizzo: Van Dyke, T Univ N Carolina, Dept Biochem & Biophys, Chapel Hill, NC 27599USA Univ N Carolina Chapel Hill NC USA 27599 l Hill, NC 27599 USA
Citazione:
X.D. Lu et al., "Selective inactivation of p53 facilitates mouse epithelial tumor progression without chromosomal instability", MOL CELL B, 21(17), 2001, pp. 6017-6030

Abstract

We examined the selective pressure for, and the impact of, p53 inactivation during epithelial tumor evolution in a transgenic brain tumor model. In TgT(121) Mice, cell-specific inactivation of the pRb pathway in brain choroid plexus epithelium initiates tumorigenesis and induces p53-dependent apoptosis. We previously showed that p53 deficiency accelerates tumor growth dueto diminished apoptosis. Here we show that in a p53(+/-) background, slow-growing dysplastic tissue undergoes clonal progression to solid angiogenic tumors in all animals. p53 is inactivated in all progressed tumors, with loss of the wild-type allele occurring in 90% of tumors. Moreover, similar progression occurs in 38% of TgT(121)p53(+/+) mice, also with loss of at least one p53 allele and inactivation of p53. Thus, the selective pressure for p53 inactivation, likely based on its apoptotic function, is high. Yet, in all cases, p53 inactivation correlates with progression beyond apoptosis reduction, from dysplasia to solid vascularized tumors. Hence, p53 suppressestumor progression in this tissue by multiple mechanisms. Previous studies of fibroblasts and hematopoietic cells show that p53 deficiency can be associated with chromosomal instability, a mechanism that may drive tumor progression. To determine whether genomic gains or losses are present in tumors that progress in the absence of p53, we performed comparative genomic hybridization analysis. Surprisingly, the only detectable chromosomal imbalance was partial or complete loss of chromosome 11, which harbors the p53 gene and is thus the selected event. Flow cytometry confirmed that the majority of tumor cells were diploid. These studies indicate that loss of p53 function is frequent under natural selective pressures and furthermore that p53 loss can facilitate epithelial tumor progression by a mechanism in addition to apoptosis reduction and distinct from chromosomal instability.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 26/01/20 alle ore 10:04:36