Figure 2

Human gene expression profiles of irinotecan-treated colon tumor xenografts. The results of unsupervised hierarchical clustering of 19,818 human probe sets showing significant expression in xenograft samples are summarized in a dendogram in panel A. Numbers in red above the clusters in the tree indicate the percentage of times these clusters were observed in 3,999 iterations during bootstrap analysis. Panel B shows the results of unsupervised hierarchical clustering of 130 human probe sets, for which variation of expression was more specifically influenced by irinotecan than intertumor variability. Numbers in red above the clusters in the tree indicate the percentage of times these clusters were observed in 3,999 iterations during bootstrap analysis. Red indicates high relative expression; green indicates low relative expression.