Growth factors induce early pre-replicative changes in senescent human fibroblasts.
EMBO J
; 5(9): 2157-62, 1986 Sep.
Article
em En
| MEDLINE
| ID: mdl-3023058
ABSTRACT
As human fibroblasts in culture senesce their response to platelet-derived growth factor (PDGF) becomes attenuated. To clarify at which level such cells are blocked in the pre-replicative part of the cell cycle, we have analysed PDGF-induced pre-replicative events in senescent (phase III) cultures. We found that phase III cells retain a normal number of PDGF receptors and that these are functional with regard to PDGF-induced receptor autophosphorylation. Phase III cells also respond to PDGF by rapid actin reorganization and increased levels of c-fos and c-myc mRNA, similar to growth-arrested phase II fibroblasts. However, the expression of the nuclear antigen K-67, which in phase II cell is induced in S-phase and continues to be expressed throughout the cell cycle, is not induced in phase III cells in response to PDGF. We conclude that phase III human fibroblasts, although blocked with regard to proliferation, still retain a functional growth factor receptor system, and display early responses when exposed to growth factors, such as changes in the cytoskeleton and the expression of proto-oncogenes.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Fator de Crescimento Derivado de Plaquetas
/
Fibroblastos
Limite:
Humans
/
Male
/
Newborn
Idioma:
En
Ano de publicação:
1986
Tipo de documento:
Article