Characteristic gene clusters. Some of the correlated genes grouped into clusters and noted at the left side of the hierarchical clustering figures are reported. They correspond either to a specific type of contaminating cell (T cells) or a tissue type (stroma, spleen). The gene expression of 3 clusters were more specifically related to the 3 lymphoma entities: SLL, MZL, and MCL. SLL indicates small lymphocytic lymphoma; MZL, marginal zone lymphoma; MCL, mantle cell lymphoma; BC, borderline cases; CCND1, cyclin D1. Gene names are available on the Blood website as supplemental data (Table S1); see the Data Set link at the top of the online article.