MSP analysis showed that Zp and Rp methylation was detected in virtually all 38 NPC tumors, with unmethylated Zp and Rp only detected in rare cases (Figure 3A, B), well correlated with the general silencing of BZLF1 and BRLF1 in NPC (Figure 3C). This evidence concerns the gene BLOC1S3 and nasopharyngeal carcinoma.