Cellular senescence
Series edited by Pier Giuseppe Pelicci
Cellular life span is restrained by signaling pathways activated by DNA damage, telomere dysfunction, and environmental stresses. Cells entering a state of senescence undergo a permanent cell cycle arrest, and functional and morphological changes. This series investigates the molecular pathways associated with execution of the senescence program and how it contributes to aging and tumor suppression.
Articles in series
Abstract
Mammalian aging occurs in part because of a decline in the restorative capacity of tissue stem cells. These self-renewing cells are rendered malignant by a small number of oncogenic mutations, and overlapping tumor suppressor mechanisms (e.g., p16INK4a-Rb, ARF-p53, and the telomere) have evolved to ward against this possibility. These beneficial antitumor pathways, however, appear also to limit the stem cell life span, thereby contributing to aging.
Authors
Norman E. Sharpless, Ronald A. DePinho
Abstract
Damage to DNA, the prime target of anticancer therapy, triggers programmed cellular responses. In addition to apoptosis, therapy-mediated premature senescence has been identified as another drug-responsive program that impacts the outcome of cancer therapy. Here, we discuss whether induction of senescence is a beneficial or, rather, a detrimental consequence of the therapeutic intervention.
Authors
Pascal Kahlem, Bernd Dörken, Clemens A. Schmitt
Abstract
Stem cells generate the differentiated cell types within many organs throughout the lifespan of an organism and are thus ultimately responsible for the longevity of multicellular organisms. Therefore, senescence of stem cells must be prevented. Bmi1 is required for the maintenance of adult stem cells in some tissues partly because it represses genes that induce cellular senescence and cell death.
Authors
In-Kyung Park, Sean J. Morrison, Michael F. Clarke
Abstract
Stem/progenitor cells ensure tissue and organism homeostasis and might represent a frequent target of transformation. Although these cells are potentially immortal, their life span is restrained by signaling pathways (p19-p53; p16-Rb) that are activated by DNA damage (telomere dysfunction, environmental stresses) and lead to senescence or apoptosis. Execution of these checkpoint programs might lead to stem cell depletion and organism aging, while their inactivation contributes to tumor formation.
Authors
Pier Giuseppe Pelicci
Abstract
Cells entering a state of senescence undergo a permanent cell cycle arrest, accompanied by a set of functional and morphological changes. Senescence of cells occurs following an extended period of proliferation in culture or in response to various physiologic stresses, yet little is known about the role this phenomenon plays in vivo. The study of senescence has focused largely on its hypothesized role as a barrier to extended cell division, governed by a division-counting mechanism in the form of telomere length. Here, we discuss the biological functions of cellular senescence and suggest that it should be viewed in terms of its role as a general cellular stress response program, rather than strictly as a barrier to unlimited cycles of cell growth and division. We also discuss the relative roles played by telomere shortening and telomere uncapping in the induction of senescence.
Authors
Ittai Ben-Porath, Robert A. Weinberg
Copyright © 2024 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)