# Cellular senescence

Cellular senescence is what happens when a cell stops dividing for good but refuses to die. Stress sets it off: DNA damage, frayed telomeres, a switched-on cancer gene, or oxidative stress. These "retired" cells stay active and leak a pro-inflammatory cocktail of signaling molecules (cytokines, chemokines, and enzymes) called the SASP. In small doses that is useful, since it blocks tumors early and helps wounds heal. The problem is they pile up as you age, and that build-up irritates surrounding tissue and drives many age-related diseases.

## Sources

- Hayflick & Moorhead. (1961). The serial cultivation of human diploid cell strains. Experimental Cell Research. https://doi.org/10.1016/0014-4827(61)90192-6
- Campisi. (2013). Aging, Cellular Senescence, and Cancer. Annual Review of Physiology. https://doi.org/10.1146/annurev-physiol-030212-183653

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_Canonical: https://longevity-switzerland.com/en/glossary/cellular-senescence · Part of Longevity Cities · Updated 2026-06-22_