NFKB1 and esophageal squamous cell carcinoma: No independent role of either NFKB1 -94ATTG ins/del or NFKBIA (-826 C>T and 3’UTR A>G) polymorphisms in ESCC susceptibility was found, however, two haplotypes of NFKBIA polymorphisms (C-826 G3’UTR and T-826 A3’UTR) seem to have protective role in ESCC.