HIF1A and nasopharyngeal carcinoma: These results not only indicate the α7AChR and ERK signaling pathways play important roles in mediating nicotine’s effect on promoting VEGF/PEDF ratio in NPC cells, but also show that the 7AChR and ERK signaling mediates nicotine’s effect on promoting VEGF/PEDF ratio through upregulation of the HIF-1α signaling in NPC cells.