In lung adenocarcinoma of hamsters, the overexpression of PKA, cAMP, CREB and phosphorylated CREB in β2-adrenergic receptor pathway and EGFR-specific phosphorylated tyrosine kinase, Raf-1 and ERK1/2 and their phosphorylated forms in EGFR pathway were observed [20]. Here, CREB1 is linked to lung adenocarcinoma.