Sex-dependent differences in intestinal tumorigenesis induced in Apc1638N/+ mice by exposure to γ rays.
Int J Radiat Oncol Biol Phys
; 85(1): 223-9, 2013 Jan 01.
Article
em En
| MEDLINE
| ID: mdl-22503525
ABSTRACT
PURPOSE:
The purpose of the present study was to assess the effect of 1 and 5 Gy radiation doses and to investigate the interplay of gender and radiation with regard to intestinal tumorigenesis in an adenomatous polyposis coli (APC) mutant mouse model. METHODS AND MATERIALS Apc1638N/+ female and male mice were exposed whole body to either 1 Gy or 5 Gy of γ rays and euthanized when most of the treated mice became moribund. Small and large intestines were processed to determine tumor burden, distribution, and grade. Expression of proliferation marker Ki-67 and estrogen receptor (ER)-α were also assessed by immunohistochemistry.RESULTS:
We observed that, with both 1 Gy and 5 Gy of γ rays, females displayed reduced susceptibility to radiation-induced intestinal tumorigenesis compared with males. As for radiation effect on small intestinal tumor progression, although no substantial differences were found in the relative frequency and degree of dysplasia of adenomas in irradiated animals compared with controls, invasive carcinomas were found in 1-Gy- and 5-Gy-irradiated animals. Radiation exposure was also shown to induce an increase in protein levels of proliferation marker Ki-67 and sex-hormone receptor ER-α in both non tumor mucosa and intestinal tumors from irradiated male mice.CONCLUSIONS:
We observed important sex-dependent differences in susceptibility to radiation-induced intestinal tumorigenesis in Apc1638N/+ mutants. Furthermore, our data provide evidence that exposure to radiation doses as low as 1 Gy can induce a significant increase in intestinal tumor multiplicity as well as enhance tumor progression in vivo.
Texto completo:
1
Coleções:
01-internacional
Temas:
Geral
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Tipos_de_cancer
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Outros_tipos
Base de dados:
MEDLINE
Assunto principal:
Genes APC
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Raios gama
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Neoplasias Intestinais
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Neoplasias Induzidas por Radiação
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Int J Radiat Oncol Biol Phys
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Estados Unidos