Figure 2. Integrated analysis of breast tumors and cell lines using the "intrinsic" gene set. Cluster diagram (see legend to figure 1) depicting the relationships between gene expression patterns in breast cancer derived cell lines and tumor specimens. A) Experimental sample associated dendrogram showing distinct tumor and cell line subtypes. B) Luminal/ER+ gene expression cluster. C) Common epithelial cell cluster containing E-cadherin. D) ERBB2+ amplicon cluster. E) Basal epithelial cell cluster. The color scale at the top right depicts the gene expression measured in each sample relative to the average expression for each gene as determined in the 87 different samples. The full microarray data files for all 87 experiments can be obtained from the Stanford Microarray Database at, and the full cluster diagrams for Figures 1 and 2 can be seen at