Among these, global levels of PTPRM, MCAM, DEFA1B, CFHR1, BST1, PF4, VTN, and C7 were significantly higher in the PCa group than in the BPH group, and LSAMP, TFRC, KLKB1, ABI3BP, GPX3, AHSG, GSN, B2M, FETUB, LRG1, and C1QC were significantly lower in the PCa than in the BPH. The gene discussed is DEFA1B; the disease is posterior cortical atrophy.