Figure 1

Changes in gene expression over time in tamoxifen-treated xenografts. (a) Comparison of the change in tumor volume over time in tamoxifen-treated and untreated (estrogen-supplemented) xenograft tumors. Values are the mean of four xenografts and error bars represent the standard error. (b) Heatmap illustrating genes with significantly increased (red) or decreased (green) expression in response to tamoxifen in the xenografts relative to no treatment. Underlined genes are those predicted to have estrogen-response elements (EREs) in their promoter regions. (c) Change in mean expression level (log2 fold change) of genes over time in xenografts treated with 17β-estradiol and tamoxifen (red). The changes shown in blue are those reported by Mutarelli and colleagues for 17β-estradiol alone [10].