(A) Confocal immunofluorescence images are displayed characterizing HUVSMCs. The panels indicate that these cells are vimentin (left panel) and smooth muscle actin (middle panel) positive but VE-cadherin (right panel) negative. Original magnification, ×200. (B) Vehicle, Nutlin-3B (Nut-3B) (7.5 μM), or Nutlin-3A (7.5 μM) was added to proliferating HUVSMCs at various time points with FGF-2 or 5% FBS. Various concentrations (0, 7.5, 15, 30 μM) of Nutlin-3A were added to cultures of serum-free, unchallenged HUVSMCs for 24 hours (lower panel). (C) Representative images of serum-free HUVSMCs supplemented with FGF-2 after 72 hours of culture. Original magnification, ×100. Data are mean ± SD and representative of 4 separate experiments performed in at least duplicate. NS, P > 0.05.