Dose-dependent effect of IL-2 in the tumor microenvironment. (a) Clusterogram of genes differentially expressed between FNA samples obtained 3 h after the first dose of IL-2 (as in Figure 5). Genes were selected using an unpaired t-test (p2 < 0.05). In this fashion, 54 genes were identified whose modulation of expression was altered only after four doses of IL-2 (upregulated, light blue panel; downregulated, green panel). (b) The same gene selection as in (a) analyzed in leukocyte subsets (blue bar) as in Figure 4, and in PBMC in vitro (yellow bar) and in vivo (green bar) (see Figure 3). Ratios are displayed according to the central method for display using a normalization factor as recommended by Ross et al. .