Taken together, our IHC, RT-PCR, and Western blot results have confirmed that the aberrant PIK3CD-S splice variant is upregulated in AA PCa vs. EA PCa at the mRNA and protein levels, and the higher PI3Kδ-S expression level enhanced the activation of the AKT/mTOR signaling in AA PCa. This evidence concerns the gene AKT1 and posterior cortical atrophy.