We examined the effect of SSa on the NF-κB signaling pathway and found that SSa treatment induced significant IκBα (the NF-κB inhibitory protein) phosphorylation at Ser32 in SSa-sensitive colon cancer cells (LoVo, SW480, HT29, SW620) but not in SSa-resistant cells of other cancer types (H1299, Hs 578T, U937) (data not shown). This evidence concerns the gene NFKB1 and cancer.