Reprogramming of epithelial differentiation toward a hypersecretory phenotype has been linked to increased expression of the epidermal growth factor receptor (EGFR)72 and to the activity of TH2 cytokines, including IL-13 and IL-9.77, 78 Consistent with this, patients with TH2-high asthma have significantly increased airway mucin gene expression.79 This evidence concerns the gene IL13 and asthma.