NFBD1 has important roles in DNA damage response (DDR), involving a complex network of signaling pathways that regulates cell cycle checkpoints, DNA repair and cell death.35, 36, 37, 38 To understand the role of NFBD1 in NPC, a stable NPC cell line NFBD1-shRNA was first developed, which expressed downregulation of NFBD1. The gene discussed is MDC1; the disease is nasopharyngeal carcinoma.