Clusterin/apolipoprotein J is a novel biomarker of cellular senescence that does not affect the proliferative capacity of human diploid fibroblasts.
FEBS Lett
; 509(2): 287-97, 2001 Dec 07.
Article
em En
| MEDLINE
| ID: mdl-11741605
ABSTRACT
Normal human fibroblasts have a limited replicative potential in culture and eventually reach a state of irreversible growth arrest, termed senescence. In a previous study aiming to identify genes that are differentially regulated during cellular senescence we have cloned clusterin/apolipoprotein J (Apo J), a 80 kDa secreted glycoprotein. In the current report we pursue our studies and show that senescence of human diploid fibroblasts is accompanied by up-regulation of both Apo J mRNA and protein levels, but with no altered biogenesis, binding partner profile or intracellular distribution of the two Apo J forms detected. To analyze the causal relationship between senescence and Apo J protein accumulation, we stably overexpressed the Apo J gene in primary as well as in SV40 T antigen-immortalized human fibroblasts and we showed no alteration of the proliferative capacity of the transduced cells. Despite previous reports on tumor-derived cell lines, overexpression of Apo J in human fibroblasts did not provide protection against apoptosis or growth arrest induced by hydrogen peroxide. Overall, our results suggest that Apo J overexpression does not induce senescence but it is rather a secondary consequence of the senescence phenotype. To our knowledge this is the first report that provides a functional analysis of human Apo J during replicative senescence.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Glicoproteínas
/
Antígenos de Diferenciação
/
Senescência Celular
/
Chaperonas Moleculares
/
Fibroblastos
Limite:
Humans
Idioma:
En
Revista:
FEBS Lett
Ano de publicação:
2001
Tipo de documento:
Article