To assess the expression levels of PI3Kδ isoforms in the PCa samples on the TMA, three independent IHC assays were performed to examine the expression profiles of α-methylacyl CoA racemase (AMACR, a potential PCa biomarker), PI3Kδ (using a general PI3Kδ antibody recognizing all PI3Kδ isoforms) and PI3Kδ-S splice isoform (using PI3Kδ-S specific antibody). The gene discussed is AMACR; the disease is posterior cortical atrophy.