Germline Mutations in Mtap Cooperate with Myc to Accelerate Tumorigenesis in Mice.
PLoS One
; 8(6): e67635, 2013.
Article
em En
| MEDLINE
| ID: mdl-23840755
ABSTRACT
OBJECTIVE:
The gene encoding the methionine salvage pathway methylthioadenosine phosphorylase (MTAP) is a tumor suppressor gene that is frequently inactivated in a wide variety of human cancers. In this study, we have examined if heterozygosity for a null mutation in Mtap (Mtap(lacZ)) could accelerate tumorigenesis development in two different mouse cancer models, Eµ-myc transgenic and Pten(+/-) .METHODS:
Mtap Eµ-myc and Mtap Pten mice were generated and tumor-free survival was monitored over time. Tumors were also examined for a variety of histological and protein markers. In addition, microarray analysis was performed on the livers of Mtap(lacZ/+) and Mtap (+/+) mice.RESULTS:
Survival in both models was significantly decreased in Mtap(lacZ/+) compared to Mtap(+/+) mice. In Eµ-myc mice, Mtap mutations accelerated the formation of lymphomas from cells in the early pre-B stage, and these tumors tended to be of higher grade and have higher expression levels of ornithine decarboxylase compared to those observed in control Eµ-myc Mtap(+/+) mice. Surprisingly, examination of Mtap status in lymphomas in Eµ-myc Mtap(lacZ/+) and Eµ-myc Mtap(+/+) animals did not reveal significant differences in the frequency of loss of Mtap protein expression, despite having shorter latency times, suggesting that haploinsufficiency of Mtap may be playing a direct role in accelerating tumorigenesis. Consistent with this idea, microarray analysis on liver tissue from age and sex matched Mtap(+/+) and Mtap(lacZ/+) animals found 363 transcripts whose expression changed at least 1.5-fold (P<0.01). Functional categorization of these genes reveals enrichments in several pathways involved in growth control and cancer.CONCLUSION:
Our findings show that germline inactivation of a single Mtap allele alters gene expression and enhances lymphomagenesis in Eµ-myc mice.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas Proto-Oncogênicas c-myc
/
Mutação em Linhagem Germinativa
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PTEN Fosfo-Hidrolase
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Carcinogênese
/
Proteínas Associadas aos Microtúbulos
Tipo de estudo:
Prognostic_studies
Limite:
Animals
/
Humans
Idioma:
En
Revista:
PLoS One
Assunto da revista:
CIENCIA
/
MEDICINA
Ano de publicação:
2013
Tipo de documento:
Article