Expression data of growing and senescent human fibroblasts (BJ cells) after p21 knockdown

Cellular senescence is a permanent state of cell cycle arrest that protects the organism from tumorigenesis and regulates tissue integrity upon damage and during tissue remodeling. However, accumulation of senescent cells in tissues during aging contributes to age-related pathologies. A deeper understanding of the mechanisms regulating the viability of senescent cells is therefore required. Here we show that the CDK inhibitor p21 (CDKN1A) maintains the viability of DNA damage-induced senescent cells. To identify the molecular mechanism controlling senescence cell viability, we studied the expression patterns of damage induced senescent (DIS) and control cells with and without p21 knockdown. Growing and DIS BJ cells were transfected with siRNAs against p21 or control siRNAs. After 3 days, total RNA was extracted and gene expression was determined using Affymetrix microarrays.