BZLF1 (encoding Zta) and BRLF1 (encoding Rta) are immediate early lytic genes pivotal for initiating the lytic gene expression cascade by stimulating lytic EBV promoters.4 Given the undetectable expression of these two lytic genes in most NPC samples, no correlation was observed between BZLF1 or BRLF1 and KDM5B (Supplementary Fig. 1a). This evidence concerns the gene KDM5B and nasopharyngeal carcinoma.