Metastatic PCa cells can produce high levels of OPG (an inhibitor of RANKL) as well as a variety of other factors like PTHrP, M-CSF, TGF-β, uPA-plasmin, matrix metalloproteinases (MMP2 and 9), and interleukins 1 and 6 [7, 55]. This evidence concerns the gene PTHLH and posterior cortical atrophy.