HK2 is a transcriptional target of LMP1 and is overexpressed in HRS cells. (A) Ectopic expression of LMP1 in L428 cells up-regulated the expression of HK2 (mRNA [left] and protein [right]). (B) Immunohistochemistry was used to study the expression of HK2 in primary HL. (Top) Low-level HK2 expression in germinal center (GC) and mantle zone (MZ) B cells of normal tonsil. (Middle, bottom) Strong staining of HK2 in HRS cells (arrow). Images were acquired using a Zeiss Photomicroscope II (Zeiss UK) equipped with a Nikon Coolpix990 camera and using Corel Paint Shop Pro v.10 software. All images were acquired using a 60 ×/1.4 NA oil-immersion objective lens.