Fig. 2.

Markers of cellular senescence. Markers most commonly used to identify senescent cells include cell cycle arrest, p16, p21, Lamin B1 downregulation, γH2AX, SA‐β‐gal and the SASP. However, neither of these markers is truly specific to senescent cells. For example, quiescent cells also exhibit cell cycle arrest and, in some cases, increased SA‐β‐gal activity. It is important to combine several markers in a battery of tests in order to identify senescent cells. [Colour figure can be viewed at wileyonlinelibrary.com]