The most relevant changes in the total profile of the B fractions when comparing blood serum PSA from aggressive PCa patients with standard PSA (Fig. 4a), were a noteworthy decrease of the disialylated core fucosylated glycan structures with α2,6-SA at 10.0 GU, which was the main peak in standard PSA (Fig. 1), and an increase of the structures containing GalNAc: FA2G1GalNAc1S2 (α2,6/α2,3) and FA2G1GalNAc1S1 (α2,6) at 9.1 and 8.3 GUs, respectively. The gene discussed is KLK3; the disease is posterior cortical atrophy.