Nuclear factor kappa B (NF-xcexbaB) is a chief nuclear transcription factor that controls the transcription of various genes, and its activation is tightly controlled by Inhibitor kappa B kinase (IKK). The irregular transcription of NF-xcexbaB has been linked to auto-immune disorders, cancer and other diseases. The IKK complex is composed of three units, IKKxcexb1, IKKxcexb2, and the regulatory domain NEMO, of which IKKxcexb2 is well understood in the canonical pathway. Therefore, the inhibition of IKKxcexb2 by drugs forms the molecular basis for anti-inflammatory drug research.