In this study, we cocultured osteoblasts (hFOB1.19 cells) and their precursors (human bone marrow mesenchymal stem cells (hBMSCs)) with prostate cancer (PC3) cells to simulate the effects of the bone and bone marrow microenvironments on prostate cancer cells and investigated the relationship between the RANKL/RANK/OPG signaling pathway and CD59 expression. The gene discussed is CD59; the disease is Familial prostate cancer.