APP and Alzheimer disease: Since we found that a reduced level of mature APP in AD-affected cells was accompanied by a mislocalization of the APP from the Golgi and consequent accumulation into recycling endosomes (Figure 3, Figures S1 and S2), we speculated that the APP was not able to be correctly modified for maturation probably because of its inability to transit through the secretory pathway and to reach the Golgi apparatus, where the majority of the APP modifications occurs.