We first found a significant upregulation of SPAG5 expression in primary PCa relative to normal prostate tissues, metastatic PCa relative to primary PCa, CRPC relative to hormone naïve PCa, and NEPC relative to prostate adenocarcinoma through microarray analysis, indicating SPAG5 may has a critical role in PCa progression. This evidence concerns the gene SPAG5 and posterior cortical atrophy.