Figure 3.

Schematic overview of antitumor protection by cellular senescence. Damaged cells can become apoptotic, enter the state of senescence (antiproliferative responses) or continue to replicate (expansion). When the latter occurs, a lesion may form where cells, again, can become apoptotic or enter the state of senescence. If suitable defense mechanisms are absent or fail, the lesion can further expand and by gaining additional mutations, a cancerous lesion (tumor) may be formed. Moreover, senescent cells still can escape this state and become cancerous as well. Normal cells are indicated in green, damaged cells in yellow, cancer cells in red, senescent cells in blue, and apoptotic cells in grey. Reprinted with permission from ref. [33]. Copyright 2021 American Pharmaceutical Association.