PIK3CA and Alzheimer disease: The gene interaction network analysis in CSF showed a complex picture: in the case of AMPs increasing in AD, the NFKB1 and PIK3CA interacting proteins were the main sites of multiple activation and inhibition (Supplementary Figure 5C), while in the case of AMPs decreasing in AD, the IL6 was the main site of regulation (Supplementary Figure 5D).