APP and Alzheimer disease: In our previous work we have investigated molecular details of an AD-like phenotype in a rare childhood lysosomal storage disorder NPC, showing that intracellular cholesterol accumulation within the late endosomes/lysosomes causes sequestration of the key AD proteins, APP and BACE1, within endocytic compartments leading to increased intracellular Aβ levels and APP-CTFs [20; 24].