HGF expression in DLBCL. (A) MET-positive primary DLBCLs were analyzed for HGF mRNA expression. After RNA isolation and cDNA synthesis, RT-PCR for MET and HGF was performed. β2-Microglobulin was used as housekeeping gene control. (B) Frozen sections of DLBCL cases were analyzed for the presence of expression of HGF by mRNA in situ hybridization, using DIG-labeled antisense cRNA run-off transcripts. Serial sections were stained with anti-CD68 to identify macrophages. The section was counterstained with hematoxylin. The result shown is a representative of 8 tested DLBCL cases. Image magnification: × 200.