NFKB1 and nonpapillary renal cell carcinoma: To verify this hypothesis, the protein expression pattern of several important functional factors of NF-κB pathway, including p105, p50, p65, pIκBα (S32 + S36), and IκBα, which have been proved to participate in signaling transduction and closely link to ccRCC tumorigenesis [24, 25, 28, 41], was examined in NAC- or H2O2-treated ACHN, 786-O and Caki-1 cells.