AZQ induces senescence in prostate cancer cells in vitro. (A) Structure and molecular weight of AZQ (NSC 182986). (B) Morphology and SA-β-gal staining of control DU145, PC3, and LNCaP cells and after 3 days cultured with medium containing 250 nM AZQ and with additional 3 days of recovery in drug-free medium. Scale bar, 20 µm. (C) AZQ inhibits prostate cancer cell growth. Prostate cancer cells were cultured in medium + DMSO (Control) or in medium + 250 nM AZQ for 3 days and then cultured for three additional days in drug-free medium to day 6 (+ AZQ). Viable cell number was measured as described in Materials and Methods. Student's t test, *P <.02, **P <.01.