Collectively, these results confirm that defective autophagy by abnormal VEGF/SphK pathway and sphingosine levels in NP–C mice and human fibroblasts also occur in NP–C patient neurons, and replenishment of VEGF is able to ameliorate autophagy defect by correction of sphingolipid imbalance in the NP–C patient cells. This evidence concerns the gene SPHK1 and nasopharyngeal carcinoma.