To find an effective treatment strategy, many hypotheses have been proposed to explain the pathogenesis of AD, including the amyloid cascade hypothesis [6], the presenilin hypothesis [7], the APP matrix hypothesis [8], hyperphosphorylation of tau protein [9], neuroinflammation [10], oxidative stress [11], mitochondrial dysfunction [12], endoplasmic reticulum (ER) stress [13], dysregulation of glucose [14], cholesterol and metal metabolism [15], and aberrant cell cycle reentry [16]. Here, APP is linked to Alzheimer disease.