SYK is activated in primary DLBCL tissues. (A) Immunoblotting of total and phosphorylated SYK (pY525/526) in LY7 and LY18 cell lines. Cells were stimulated with (+) or without (-) anti-BCR as described in “Methods.” (B) Immunohistochemical staining of p-SYK (pY525/526) on sections of paraffin cell blocks made from anti-BCR stimulated (+) or unstimulated (-) LY7 and LY18 cells. Photomicrographs were generated using Nikon E600, Planachromat 4/0.10/30.0, 20/0.40/1.3, PlanApo 40/0.095/0.12-0.16, and PlanFluor 40/0.75/0.72 objectives, and were captured using an Olympus DP12 camera. (C-D) Immunohistochemical staining of p-SYK on paraffin-embedded sections from tissue microarray in normal lymphoid tissues (C) and DLBCL tissues (D). The ranges for the scoring system are shown.