In addition to pathogenic proteins, we turned our attention to a number of intracellular signaling molecules implicated in AD pathogenesis, such as phosphorylated insulin receptor substrate-1 (IRS-1) species, lysosomal proteins (cathepsin-D), heat shock proteins (HSP70), cellular survival factors (REST), LRP6, and others (Fiandaca et al., 2015; Goetzl et al., 2015b; Kapogiannis et al., 2015). Here, IRS1 is linked to Alzheimer disease.