Nimbolide, one of the triterpenoids isolated from the flowers and leaves of neem, has been shown to inhibit proliferation of numerous types of tumor cells.28 One action of nimbolide is its role inhibiting NF-kB activation, which plays a critical role in tumor cell proliferation, invasion, and angiogenesis.2,29 NF-kB is a transcription factor that is activated in response to both carcinogens, such as DMBA, and pro-inflammatory cytokines, such as TNF-a, IL-1 and IL-6.28 These cytokines also play a critical role in the development of periodontitis.30 This evidence concerns the gene NFKB1 and neoplasm.