Human macrophage inflammatory protein‐3α/CCL20/LARC/Exodus/SCYA20 is transcriptionally upregulated by tumor necrosis factor‐α via a non‐standard NF‐κB site

摘要

>The 5′-flanking sequences of the human macrophage inflammatory protein-3α/CCL20 gene were cloned and transfected into G-361 human melanoma cells in a luciferase reporter construct. Tumor necrosis factor-α (TNF-α) treatment stimulated luciferase expression, and promoter truncations demonstrated that TNF-α inducibility is conferred by a region between nt −111 and −77, which contains a non-standard nuclear factor-κB (NF-κB) binding site. The requirement for NF-κB was demonstrated as follows: (i) mutations in this NF-κB site abrogated TNF-α responsiveness; (ii) TNF-α activated a construct containing two copies of the CCL20 NF-κB binding site; (iii) overexpression of NF-κB p65 activated the CCL20 promoter; (iv) NF-κB from nuclear extracts of TNF-α-stimulated cells bound specifically to this NF-κB site.