Similarly, the down-regulated genes have roles in asthma and airway modeling (PTGS2, AREG, HBEGF, PLAUR, CAMP, LTF, FCAR, PDE4B, ZNF331 and IRAK2) and immune function (NR4A3, NFIL3, ADGRE3, TARM1 and ZC3H12A). This evidence concerns the gene PDE4B and asthma.