To determine whether activation of the CXCR4/CXCL12 axis stimulates proliferation of prostate cancer progenitors, PC3 and DU145 cells were treated with CXCL12 at 10 and 100 ng/mL for 5 days in serum-free epithelial growth medium. Here, CXCR4 is linked to Familial prostate cancer.