NFKB1 and cystic fibrosis: However, Tchilibon et al. recently implicated phospho-c-JUN/c-FOS dimers in TNFα-related IL-8 expression in cystic fibrosis lung epithelial cells IB-3 and IB-3/S9 by using MRS2481, a compound inhibiting both signaling of the NF-κB and the AP-1 pathway [42].