NFKB2 and nasopharyngeal carcinoma: Four putatively functional SNPs (NFκB1: rs28362491del>ins ATTG; NFκB2: rs12769316G>A; IκBα: rs2233406C>T and rs696G>A) were analyzed to evaluate their associations with NPC risk in total 1590 NPC cases and 1979 cancer-free controls.