This parallelism between NPC and AD is further strengthened by the observation that cholesterol levels may modulate the processing of amyloid precursor protein129 and accumulation of β-amyloid130 is supported by the disease-modifying effect of the ε4 isoform of apolipoprotein E on disease progression in both NPC and AD131–133. This evidence concerns the gene APOE and nasopharyngeal carcinoma.