PTGS2 and non-small cell lung carcinoma: NF-κB is an upstream regulator of COX-2; therefore, we checked the effect of honokiol on the NF-κB in A549 and H1299 NSCLC cells, and found that treatment of these cells with honokiol decreased the level as well as activity of NF-κB/p65 in a dose-dependent manner and simultaneously down-regulated the levels of IKKα, which is responsible for NF-κB activation.