Figure 1. Restoration of CASZ1 suppresses NB cell proliferation and inhibits the cell cycle. Full-length FLAG-tagged CASZ1a in Tet-on vector was stably transfected into SY5Y (A) and NGP (B) neuroblastoma cell lines that express Tet repressor. Induction of CASZ1a expression by Tet (1 µg/mL) was visualized by immunoblotting whole-cell lysate with anti-FLAG antibody. The fold induction of CASZ1 mRNA at 24 h was detected by real-time PCR in SY5Y (C) and NGP (D). Restoration of CASZ1a in SY5Y (E) and NGP cells (F) inhibited cell proliferation (*P < 0.005; #P < 0.05). FACS analysis documenting the cell cycle distribution of SY5Ytet CASZ1a (G) or NGPtetCASZ1a (H) upon restoration of CASZ1a for 2 d.