Prostate cancer cell lines with varied PSMA expression in vitro were used, where the highly PSMA expressing LNCaP cell line (1.7×105 receptors per cell) was quantitatively compared with the minimally PSMA expressing PC-3 cell line [6.6×103 receptors per cell, Fig. 1(a)]. This evidence concerns the gene FOLH1 and Familial prostate cancer.