To investigate this possibility, we first overexpressed BRRF1 in EBV-infected cell lines (HK1-EBV and HONE1-EBV), clinically derived NPC cell lines (C666-1 and NPC43) [29], and gastric cancer cell lines (AGS, NCC-24 and SNU719), and detected the gene expression of BTN2A1 and BTN3A1, via RT–qPCR (Figure 1A–D and Figure S1). The gene discussed is BTN2A1; the disease is gastric cancer.