Herein we found PPARβ/δ expression is in reverse correlation with the degree of differentiation in the NPC cell lines, the most striking reduction was observed in the EBV positive undifferentiated NPC C666-1 cells, where GW501516 treatment could inhibit the growth of NPC cells at both in vitro and in vivo level, through impairing cell cycle progression and promoting apoptosis by activation of the AMPKα and downregulation the expression of integrin-linked kinase (ILK). Here, ILK is linked to nasopharyngeal carcinoma.