While an increased expression of APP is clearly established in AD (Podlisny et al., 1987; Rovelet-Lecrux et al., 2006; Theuns et al., 2006; LaFerla et al., 2007), APP is also overexpressed in numerous cancers, including colorectal cancer (Hansel et al., 2003; Ko et al., 2007; Arvidsson et al., 2008; Krause et al., 2008). Here, APP is linked to Alzheimer disease.