NQO1 and nasopharyngeal carcinoma: Consistent with our previous report, RKIP is significantly downregulated in NPC, particularly in radioresistant NPC (Fig. 6a, Table 1), whereas, the level of NRF2 and NQO1 is remarkably upregulated in NPC specimens (Fig. 6a, Table 1), especially in radioresistant ones (Fig. 6a, Table 1).