Expression levels (log₂) of genes with statically significant difference. Differences were (A) between samples of FL before (group 3, FL pre–t-DLBCL) and after (group 4, DLBCL post-FL) transformation and (B) between FL before transformation (group 3, FL pre–t-DLBCL) and FL without subsequent transformation (group 1, FL). For each box, plots are shown in top panel and mean rank statistic in bottom panel.