NFKB1 and renal cell carcinoma: We also found that after reducing the methylation levels of the QPCT promoter region by decitabine in RCC cells, the binding of NF-κB (p65) to QPCT was increased (Figure 4E), which indicated that a hypermethylation of the QPCT promoter region might inhibit the binding of NF-κB (p65).