Stress-induced premature senescence in BJ and hTERT-BJ1 human foreskin fibroblasts

To test the involvement of the telomeres in the senescent phenotype, we used telomerase-immortalized human foreskin fibroblasts (hTERT-BJ1). We exposed hTERT-BJ1 and parental BJ cells to either UVB or H2O2 subcytotoxic stress(es). Both cell lines developed biomarkers of replicative senescence: loss of replicative potential, increase in senescence-associated beta-galactosidase activity, typical senescence-like morphology, overexpression of p21(WAF-1) and p16(INK-4a), and decreased level of the hyperphosphorylated form of pRb. Telomere shortening was slightly higher under stress for both BJ and hTERT-BJ1 but still much lower than that reported for other cell lines. We conclude that pathways alternative to telomere shortening must cause the appearance of the senescence phenotype. (C) 2002 Federation of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.