Senescence and cellular immortality

Cellular senescence is a state of irreversible growth arrest activated by a number of oncogenic signals. The senescence program prevents tumorigenesis via both cell and non-cell autonomous mechanisms. However, senescent cells accumulate and persist in the body during aging or following elevated genotoxic stress. Persistence of these senescent cells increases the risk of escaping from irreversible proliferative arrest, and poses serious threats to tissue homeostasis due to the chronic secretion of pro-inflammatory and pro-proliferative factors. Thus, senescent cells might favor tumor initiation and progression, and targeting senescent cells could be an effective anti-cancer strategy.