Requirement for binding of catalytically active factor VIIa in tissue factor-dependent experimental metastasis.
J Clin Invest
; 101(7): 1372-8, 1998 Apr 01.
Article
en En
| MEDLINE
| ID: mdl-9525979
ABSTRACT
Tissue factor (TF), the initiating cell surface receptor of the coagulation cascade, plays important roles in embryogenesis, angiogenesis, and tumor cell metastasis. It is controversial whether proteolytic function of TF complexed with its serine protease ligand VIIa is required for metastatic tumor dissemination. We show here in a model for TF-dependent experimental hematogenous metastasis, that TF supports metastasis by both proteolytic activity of the TF-VIIa complex and currently undefined functions of the cytoplasmic domain. We demonstrate that ligand binding of VIIa to TF is required for metastasis. Antimetastatic properties of covalently inactivated VIIa provide evidence that ligand binding is insufficient per se to support metastasis, emphasizing that proteolytic activity is necessary for the metastatic process. Ala or Asp mutations of cytoplasmic serine residues were introduced to preclude or mimic phosphorylation. In vivo analysis of these mutants suggests that local protease generation on the tumor cell surface does not serve simply to activate the cytoplasmic domain of TF by serine phosphorylation. Thus, extracellular functions of the catalytically active TF-VIIa complex cooperate with specific functions of the TF cytoplasmic domain to support the complex process of hematogenous tumor cell dissemination.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Tromboplastina
/
Factor VIIa
/
Metástasis de la Neoplasia
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
J Clin Invest
Año:
1998
Tipo del documento:
Article
País de afiliación:
Estados Unidos