Analysis of

FIG1 expression in normal lymphoid tissues and B-cell lymphomas by Northern blot and quantitative RT-PCR. (A) Northern blot analysis of FIG1 expression in naive B-cell to post–germinal center B-cell–derived lymphomas. Total RNA (5 μg) from chronic lymphocytic leukemias (CLLs), mantle cell lymphomas (MCLs), Burkitt lymphomas (Bkt), follicular lymphomas (FLs), NM-DLBLs, PMBLs, marginal zone lymphomas (MZLs), and plasmablastic DLBLs (PL-DLBLs), was loaded on each lane. Ethidium bromide–stained 28S and 18S rRNA bands are shown for comparison (top). Hybond N+ membrane was hybridized with the α-³²P–labeled human FIG1RDA fragment. (B) Quantitative RT-PCR analysis of FIG1expression in normal and tumoral lymphoid tissue samples.FIG1/S14 mRNA ratios were determined as indicated in “Materials and methods.” The FIG1/S14 mRNA ratios of normal lymphoid tissues (1 spleen, 1 thymus, 3 lymph nodes; ×), 18 cases of NM-DLBL (○), 17 cases of PMBL (●), and other B-cell lymphomas (2 CLLs, 2 MCLs, 2 Bkt, 2 FLs, 2 MZLs; ■) are represented in a scatter plot. The dashed line represents the cutoff ratio used to distinguish high and low levels FIG1 gene expression.