Genes selectively up-regulated inwttumors. Cluster 1. (Top) Seventynine genes were obtained by K-means clustering with Pearson correlation (GeneSpring 4.2.1) of 245 differentially expressed genes identified by parametric t test with Benjamini-Hochberg multiple testing correction. UR indicates unirradiated; IR, irradiated. Signal values per gene were normalized to the mean of the unirradiated controls for each sample. (Bottom) The cluster was visualized using TREEVIEW (http://www.microarrays.org/software.html). Columns represent individual B-CLL samples, and rows correspond to genes. Color changes within a row indicate expression levels relative to the average of the same population. Functional classification of the genes is indicated by different colors (key).