ABSTRACT
The nuclear factor κB (NF-κB) transcription factor, which was rst discovered in 1986, is a family of structurally related proteins that promote expression of over 150 genes involved in a variety of cellular processes (Kumar et al. 2004). It is a dimeric complex of various subunits that belongs to the Rel family, which includes RelA (p65), RelB, c-Rel, p50, and p52. In most cell types, inactive NF-κB complexes are kept in the cytoplasm via their noncovalent interaction with inhibitory proteins known as IκBs (Delhalle et al. 2004). In response to multiple stimuli, including cytokines, viral and bacterial pathogens, and stress-inducing agents, the latent cytoplasmic NF-κB/IκBα complex is activated by phosphorylation, ubiquitination, and proteosome-mediated degradation of IκB. Free and activated NF-κB translocates in the nucleus, and binds to its target DNA-binding site to initiate gene transcription. NF-κB is involved in the transcription of many proinammatory and antiapoptotic genes, and it is now considered as a key element in the progression of carcinogenesis and inammatory diseases (Heras and Hortelano 2009).
