EGF is a potent proliferative factor for NPCs that strongly promote the mitogenesis of NPCs in vitro, in the normal adult brain, and in brains injured by Aβ, ischemia, and trauma [25], [31]–[35]; the differentiation-inducing effect of EGF is weak and exhibits a glial tendency [31], [32]. The gene discussed is EGF; the disease is ischemia.