NFKB1 and Behcet disease: As expected, the protein levels of IκB (a kinase enzyme complex that is part of the upstream NF-κB signaling cascade) and NF-κB (a protein complex that induces DNA transcription and cytokine production) were significantly higher in BD than in NC rats, and were significantly downregulated in BD + Mel rats, but were upregulated in BD + Mel + Luz rats (Figure 3).