DLC1 negatively regulates angiogenesis in a paracrine fashion.
Cancer Res
; 70(21): 8270-5, 2010 Nov 01.
Article
em En
| MEDLINE
| ID: mdl-20861185
ABSTRACT
The Rho GTPase-activating protein DLC1 is a tumor suppressor that is often deleted in liver cancer and downregulated in other cancers. DLC1 regulates the actin cytoskeleton, cell shape, adhesion, migration, and proliferation through its Rho GTPase-activating protein activity and focal adhesion localization. In this study, we silenced DLC1 in nonmalignant prostate epithelial cells to explore its tumor suppression functions. Small hairpin RNA-mediated silencing of DLC1 was insufficient to promote more aggressive phenotypes associated with tumor cell growth. In contrast, DLC1 silencing promoted pro-angiogenic responses through vascular endothelial growth factor (VEGF) upregulation, accompanied by the accumulation of hypoxia-inducible factor 1α and its nuclear localization. Notably, modulation of VEGF expression by DLC1 was dependent on epidermal growth factor receptor-MAP/ERK kinase-hypoxia-inducible factor 1 signaling but on RhoA pathways. Clinically, VEGF upregulation is a highly significant event in prostate cancers in which DLC1 is downregulated. Thus, our results strongly suggest that loss of DLC1 may serve as a "second hit" in promoting angiogenesis in a paracrine fashion during tumorigenesis.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Neoplasias da Próstata
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Comunicação Parácrina
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Proteínas Ativadoras de GTPase
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Proteínas Supressoras de Tumor
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Neovascularização Patológica
Tipo de estudo:
Prognostic_studies
Limite:
Animals
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Humans
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Male
Idioma:
En
Ano de publicação:
2010
Tipo de documento:
Article