CDK5 and Alzheimer disease: As for Si-CDK5, it attenuated CDK5 expression (Figures 11A,B) and cell apoptosis (Figures 11C,D) in both NC- and FOXQ1 siRNA–treated primary neuron AD models; meanwhile, Si-CDK5 enhanced neurite outgrowth in FOXQ1 siRNA–treated primary neuron AD model but not in NC primary neuron AD model (Figures 11E,F).