An Msh2 conditional knockout mouse for studying intestinal cancer and testing anticancer agents.
Gastroenterology
; 138(3): 993-1002.e1, 2010 Mar.
Article
en En
| MEDLINE
| ID: mdl-19931261
BACKGROUND & AIMS: Mutations in the DNA mismatch repair (MMR) gene MSH2 cause Lynch syndromes I and II and sporadic colorectal cancers. Msh2(null) mice predominantly develop lymphoma and do not accurately recapitulate the colorectal cancer phenotype. METHODS: We generated and examined mice with a conditional Msh2 disruption (Msh2(LoxP)), permitting tissue-specific gene inactivation. ECMsh2(LoxP/LoxP) mice carried an EIIa-Cre transgene, and VCMsh2(LoxP/LoxP) mice carried a Villin-Cre transgene. We combined the VCMsh2(LoxP) allele with either Msh2(Delta7null) (VCMsh2(LoxP/null)) or Msh2(G674D) mutations (VCMsh2(LoxP/G674D)) to create allelic phase mutants. These mice were given cisplatin or 5-fluorouracil/leucovorin and oxaliplatin (FOLFOX), and their tumors were measured by magnetic resonance imaging. RESULTS: Embryonic fibroblasts from ECMsh2(LoxP/LoxP) mice do not express MSH2 and are MMR deficient. Reverse transcription, polymerase chain reaction, and immunohistochemistry from VCMsh2(LoxP/LoxP) mice demonstrated specific loss of Msh2 messenger RNA and protein from epithelial cells of the intestinal tract. Microsatellite instability was observed in all VCMsh2 strains and limited to the intestinal mucosa. Resulting adenomas and adenocarcinomas had somatic truncation mutations to the adenomatous polyposis coli (Apc) gene. VCMsh2(LoxP/LoxP) mice did not develop lymphoma. Comparison of allelic phase tumors revealed significant differences in multiplicity and size. When treated with cisplatin or FOLFOX, tumor size was reduced in VCMsh2(LoxP/G674D) but not VCMsh2(LoxP/null) tumors. The apoptotic response to FOLFOX was partially sustained in the intestinal mucosa of VCMsh2(LoxP/G674D) animals. CONCLUSIONS: Msh2(LoxP/LoxP) mice in combination with appropriate Cre recombinase transgenes have excellent potential for preclinical modeling of Lynch syndrome, MMR-deficient tumors of other tissue types, and use in drug development.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Adenocarcinoma
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Protocolos de Quimioterapia Combinada Antineoplásica
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Neoplasias Colorrectales Hereditarias sin Poliposis
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Adenoma
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Cisplatino
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Ratones Noqueados
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Proteína 2 Homóloga a MutS
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Neoplasias Intestinales
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Antineoplásicos
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Gastroenterology
Año:
2010
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
Estados Unidos