EBF1 and gastric carcinoma: As we were unable to achieve sufficient knock-down of EBF1 to examine this possibility in LCLs (perhaps reflecting the fact that EBF1 is required for the survival of these cells) [48], we performed reporter gene assays in the EBV negative AGS gastric carcinoma cell line to examine the effect of co-transfected EBF1 protein on the activity of the EBV BZLF1 (Zp) or BRLF1 (Rp) IE promoters (S5 Fig).