Metastatic PCa cells can undergo a phenotypic switch towards an OB-like phenotype by synthesizing and secreting osteocalcin, osteopontin (22), osteoprotegerin (OPG), etc. OPG is an anti-osteolytic agent that can antagonize receptor activators of nuclear factor κB ligand (RANKL, central to OC differentiation) (23). The gene discussed is BGLAP; the disease is posterior cortical atrophy.