NFKB1 and neoplasm: Because the NF-κB signaling pathway is involved in many important biological processes, such as cell proliferation, apoptosis, and tumor metastasis, we investigated the inhibitory mechanisms and identified RA targets in the NF-κB pathway that might be responsible for most of the known activities of RAs reported to date, including the anti-proliferative, antiinflammatory, anti-angiogenesis, and apoptotic activities.