NPC1 and nasopharyngeal carcinoma: Although it is not clear whether this altered presynaptic input on PCs may contribute to the progressive degeneration of these cells and the behavioral impairments typical of NPC, these results indicate that both neuronal and glial NPC1 are required for proper presynaptic development and, added to the previous observations, confirm that neurons and astrocytes may cooperate in NPC disease progression.