Expression profiles of mantle cell lymphoma (MCL) signature genes in 6 cases of cyclin D1-negative MCL using Affymetrix U133 A/B arrays. These expression profiles are compared with 22 cases of cyclin D1-positive MCL, 78 cases of activated B-cell-like (ABC), 85 cases of germinal center B-cell-like (GCB), and 33 cases of primary mediastinal (PMBL) variants of diffuse large B-cell lymphoma, 193 cases of follicular lymphoma (FL), 14 cases of extranodal marginal zone lymphoma, MALT type (MALT), 6 cases of splenic marginal zone lymphoma (SMZL), and 14 cases of small lymphocytic lymphoma (SLL) (median expression levels of the MCL signature genes in these entities are shown). In the 6 cases of cyclin D1-negative MCL, each column represents a single lymphoma specimen and each row represents the level of expression of a single gene in the MCL signature. Red squares indicate increased expression and green squares indicate decreased expression relative to the median expression level, according to the color scale shown over a 4-fold range. In the bottom panel, the gene expression levels of the D-type cyclins in the various entities and the 6 cases of cyclin D1-negative MCL are shown according to the color scale over a 16-fold range. For microarray data of all cases, refer to Table S1.