Tel/PDGFRbeta induces stem cell differentiation via the Ras/ERK and STAT5 signaling pathways.
Exp Hematol
; 37(1): 111-121, 2009 Jan.
Article
em En
| MEDLINE
| ID: mdl-19100521
ABSTRACT
OBJECTIVE:
Fusion genes involving the platelet-derived growth factor receptor-beta (PDGFRbeta) are found in a subgroup of myeloproliferative neoplasms, with one such fusion, Tel/PDGFRbeta found in a subset of chronic myelomonocytic leukemia patients. Tel/PDGFRbeta results in constitutive activation of several signaling pathways and induces a myeloproliferative disease in mice, with signals via tyrosines 579/581 identified as being important for this phenotype. In this study, we have used a tetracycline-regulated system to express wild-type and the mutated F2 Tel/PDGFRbeta to identify the key signaling pathways, which drive Tel/PDGFRbeta-induced differentiation of embryonic stem (ES) cells. MATERIALS ANDMETHODS:
The leukemic oncogene Tel/PDGFRbeta and Tel/PDGFRbeta-F2 were inducibly expressed in ES cells and their effects on self-renewal, signal transduction, and gene expression patterns analyzed.RESULTS:
Tel/PDGFRbeta activated several major signal transduction pathways (signal transducers and activators of transcription [STAT] 3, STAT5, mitogen-activated protein kinases, phosphatidylinositol-3 kinase) in ES cells, but only specific inhibition of the mitogen-activated protein kinase kinase/extracellular regulated kinase (MEK/ERK) or STAT5 pathways was able to significantly prevent Tel/PDGFRbeta-induced differentiation and restore ES-cell self-renewal. Inhibiting the tyrosine kinase activity of the oncogene using Gleevec or PDGFRbeta inhibitor III also substantially prevented Tel/PDGFRbeta-induced differentiation and its ability to upregulate key genes involved in myelopoiesis. Tyrosines 579/581 played a critical role in mediating signals via the Ras/ERK and STAT5 pathways, with dual targeting of the tyrosine kinase activity of Tel/PDGFRbeta and the MEK/ERK pathway completely preventing Tel/PDGFRbeta-induced differentiation.CONCLUSION:
These findings suggest that targeted disruption of key signaling pathways in combination with the tyrosine kinase activity of leukemic oncogenes, such as Tel/PDGFRbeta, may result in more efficacious therapies for suppressing leukemic progression in the clinical setting.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas Repressoras
/
Células-Tronco Neoplásicas
/
Proteínas de Fusão Oncogênica
/
Diferenciação Celular
/
Proteínas ras
/
Receptor beta de Fator de Crescimento Derivado de Plaquetas
/
Sistema de Sinalização das MAP Quinases
/
MAP Quinases Reguladas por Sinal Extracelular
/
Fator de Transcrição STAT5
/
Proteínas Proto-Oncogênicas c-ets
Tipo de estudo:
Prognostic_studies
Limite:
Animals
/
Humans
Idioma:
En
Revista:
Exp Hematol
Ano de publicação:
2009
Tipo de documento:
Article