Since NF-κB pathway is highly expressed in severe asthmatics (27), and it accounts for the upregulation of pivotal pro-inflammatory cytokines in asthma pathogenesis, such as IL-13 and TNF-α (29), it is not unlikely that the anti-asthmatic effect of 15d-PGJ2 is mediated, at least in part, via a NF-κB-dependent mechanism. This evidence concerns the gene TNF and asthma.