APOA4 and Alzheimer disease: To the best of our knowledge, this is the first report of these protein levels (one ACE (namely, ACE1), and nine APOs (namely, ApoAI, ApoAII, ApoAIV, ApoB, ApoCI, ApoCIII, ApoD, ApoE, and ApoH) as biomarkers, either upregulated or downregulated for AD, CVD, and EMD, respectively.