To further test the role of FoxO1 in repressing Fzd1 and Fzd7 in the context AD, we treated our cellular AD model with a non-toxic concentration of FoxO1 inhibitor (Fig. S4K), which indeed prevented Aβ-induced Fzd1 downregulation (Fig. 4F). Here, FZD7 is linked to Alzheimer disease.