10 YEARS LATER - WHAT HAVE WE LEARNED ABOUT HUMAN AGING FROM STUDIES OF CELL-CULTURES

Human cells in culture have been used for over 30 years as models to e xamine the biology of aging. Some studies suggest that cellular aging is a genetically dominant characteristic; other studies suggest that a ging is characterized by a general dysregulation of processes and path ways. A question of major interest is to what extent replicative senes cence in culture provides insights about senescence in the organism. O verall, the findings suggest that there may be multiple cellular pathw ays to acquiring the senescent phenotype, some more relevant to organi smic aging than others. Nevertheless, by studying processes in cell cu ltures that are known to fail in aging, we can learn the cellular and molecular bases of these failures.