After the treatment with CXCL12 in the sh-CXCR4 group, DRG growth is not significantly different, but the migration ability of the PCa cells and the reciprocal effect between the PCa cells and neurites are notably inhibited compared with that in the sh-Control group with CXCL12 (Fig. 5A, D and E). The gene discussed is CXCL12; the disease is posterior cortical atrophy.