APOE and Alzheimer disease: Altogether, the differences in brain lipidomes and transcriptomic profiles associated with APOE genotypes demonstrated in our study strongly support the idea that the efficiency of unfolded protein response, response to ER stress, intracellular proteasomal and lysosomal degradation, and better preserved mitochondrial function provides a molecular background for APOE-associated differences in AD pathology, interpreted as driven by the APOEε2/c group.