Additionally, immunohistochemical analysis of pro-GDF15 in human PCa tissues and the BM of CRPC patients confirmed that pro-GDF15 was expressed not only in PCa tissues but also in bone-related cells, including human osteocytes (Fig. 4C), suggesting that all relevant cell types associated with BM can secrete GDPP in the bone microenvironment. The gene discussed is GDF15; the disease is posterior cortical atrophy.