As shown by ex vivo bioluminescent imaging, PCa cells overexpressing GDF15 exhibited widespread skeletal metastasis (in the hind limbs, forelimbs, spinal cord, and ribs with sternum) after one month of inoculation compared to that of control PC3-Luc(i) cells (Fig. 1e). The gene discussed is GDF15; the disease is posterior cortical atrophy.