Furthermore, anagen has been induced by numerous drugs, for example, minoxidil, cyclosporin A, FK506, norepinephrine-depleting agents, estrogen receptor antagonists, tretinoin, tumor promoting agents (TPAs), keratinocyte growth factor (KGF), hepatocyte growth factor (HGF), substance P, and capsaisin [50]. This evidence concerns the gene FGF7 and neoplasm.