IL1B and chronic obstructive pulmonary disease: COX2 regulates in vivo synthesis of PGE2, whose level is high in fibroblasts derived from COPD patients, whereas the stimulation by TNF-α and IL-1β, which were actually shown to be related to miR-146a expression, boosted the levels of expression of COX2/PGE2 (Togo et al., 2008; Sato et al., 2010).