Genome-wide expression signatures in RCC. A. Hierarchical clustering of 40 RCC samples across all probe sets of the HG-U133A array, identifying the 3 groups (left). Hierarchical clustering of the 40 RCC samples based on expression signal values from 769 genes identified from the SNP array analysis, show diffuse clusters prior to group acquaintance (middle), but are unraveling the 3 RCC groups when individual tumors are affiliated (here: color coded) to their respective group before clustering (right). B – C. Heatmaps of RCC group-specific signatures with corresponding intensity bars (absolute values). Relative increase (yellow) and relative decrease (blue) of gene expression. B. Gene expression of the 50 best classifiers of subgroup B against subgroups A/C across a subset of A, B and C RCC. C. Gene expression of the 24 best classifiers of subgroup A against subgroup C across a subset of A and C RCC subgroups.