Figure 7.
The effect of gene knockdown on basal and E2-stimulated cell proliferation in MCF7 cells. (A) RNAi-mediated gene knockdown was performed for selected genes of interest, listed, including those that are E2-regulated, that harbor ERα- and/or MYC-binding sites, or that are implicated in the cellular response to E2. (B) The location of ChIP-identified ERα and/or MYC transcription factor-binding sites relative to the TSS of each targeted gene (A) (see color legend). Gray color indicates that no ERα- or MYC-binding region was detected within 200 kb to the TSS of the gene. (C) E2-regulated genes identified by gene expression profiling in our study are indicated (Expression), as well as genes curated in the Dragon Estrogen Responsive Genes Database (ERGDB) (Tang et al, 2004). (D) Proliferation assays in MCF7 cells after knocking down each gene from panel A using RNAi. We measured the cellular proliferation of gene-specific RNAi cells versus control cells (treated with the control siRNA) under both E2-depleted (i.e. vehicle-treated) and E2-stimulated conditions. BrdU incorporation rates are normalized to the data from RNAi control cells grown in E2-depleted conditions (error bars denote one 1 s.d.). RNAi control cells grown in 10 nM E2-treated conditions have roughly 1.5-fold higher proliferation rates than those in E2-depleted conditions. One-way ANOVA was applied to test the significance of the proliferation changes for RNAi knockdown cells versus the RNAi control cells under hormone-stimulated or basal conditions. **P<0.01, *P<0.05.