Fig. 6.

OIP5 is a downstream gene of E2F1. (A) Immunoblot analysis of E2F1 and OIP5 in LN-229, U-87 MG, and A172 cells expressing shGFP, shE2F1#1, or shE2F1#2. (B) A total of 4 sets of primers were designed within the human OIP5 promoter, and a ChIP assay was performed using E2F1 antibodies. Immunoglobulin G was used as the negative control. Three E2F1 conserved recognition sequences were identified in the OIP5 promoter in the P2 region. (C) The OIP5 wild-type (wt) and OIP5 mutant (mt) promoter sequences were ligated into the pGL3 plasmid and co-transfected with pRL-TK. Luciferase activity was examined 48 h after transfection. (D) The expression of OIP5 correlates with E2F1 levels. (E) Gene expression profile analysis on the GDS1962 dataset using E2F1-regulated genes and other control genes. (F) Kaplan–Meier analysis of overall survival in French’s database. (G) E2F1 expression was correlated with tumor stage in French’s database. The log-rank test P-values are shown. Data were analyzed using 2-tailed Student’s t-tests, *P < 0.05, **P < 0.01.