Figure 2.

Induction of cellular senescence by PATZ1 knockdown. Young HUVECs were transfected with PATZ1 siRNA and incubated for the indicated times. (a) RT-PCR analysis of PATZ1 levels. Equal loading of RNA was estimated by the GAPDH mRNA levels. (b) SA-β-gal activity staining ( × 100) and the percentages of SA-β-gal positive cells in PATZ1 siRNA cells. (c) Cell proliferation measured by counting cells. ^*P<0.05 versus control siRNA (NC). (d) BrdU incorporation analysis by flow cytometry. (e) Cell cycle profiles of PATZ1 siRNA cells. (f) Western blotting for PATZ1, pATM, pRb, p53 and p21^CIP1 proteins in PATZ1 siRNA and control cells. (g) Accumulation of phospho-H₂AX in PATZ1 siRNA cells. (h) Tube formation in PATZ1 siRNA cells ( × 40). (i) Western blotting for PARP 1/2 and caspase 3 proteins and Annexin-V staining. Representative data from three independent experiments are shown. Values are means ±S.D. of three independent experiments. ^*P<0.05 or ^**P< 0.01 versus NC, control siRNA; siPATZ1, PATZ1 siRNA