Fig. 9. Genes that distinguish GCPs, pre-neoplastic cells and tumor cells. Microarray data were subjected to analysis of variance (ANOVA) and genes that changed more than 1.9-fold between GCPs, pre-neoplastic cells and tumor cells (with adjusted P-values <0.01 and maximum absolute intensity difference >32 units) were considered differentially expressed. Expression profiles of the 118 differentially expressed genes are shown. Colors represent relative expression level, with red denoting high and green denoting low expression (see gradient at bottom of figure). Genes were clustered based on expression pattern among the three groups.