Figure 3.

Increased expression of CDKI p27^Kip1 in senescent prostate cancer cell lines in vitro and DU145 xenografts in vivo after AZQ treatment. (A) DU145, PC3, and LNCaP cells were cultured for 3 days in medium containing 250 nM AZQ (+AZQ 3 Days) or were exposed to AZQ and cultured an additional 3 days in drug-free medium (Removal + 3 Days), protein lysates were harvested. Lysates of nonconfluent proliferating cells were used as controls. Lysates of normal human prostate epithelial cells after one and five passages were included. Expression of α-tubulin was included as a loading control. Band intensities are normalized to α-tubulin and expressed relative to controls. (B) Immunofluorescence microscopy of p27^Kip1 expression (red) in Control or +AZQ tumors harvested 7 days after a single injection of 4 mg of AZQ per kilogram body weight. DNA is stained using Hoechst 33342 (blue). Scale bar, 20 µm.