APP and early-onset autosomal dominant Alzheimer disease: It remains also unclear whether the accumulation of APP‐CTFs is a general phenomenon in Alzheimer's disease (Pera et al, 2013) and how APP‐CTFs would trigger or add to neurodegeneration, although various signaling pathways, some affecting neurite growth and dendritic arborization, have been proposed (Deyts et al, 2012).