SERPINA3 and posterior cortical atrophy: To evaluate the effects of SERPINA3 and LCN2 on PCa, we collected CM from the SERPINA3‐ or LCN2‐overexpressing HEK293T cells and administered the medium to four types of BPCa cells, C4, C4‐2, C4‐2B, and VCaP (Fig. S10A).