The expression profile of circRNAs in four pairs of PCa tissues was examined by microarray analysis (Figure 1(a)), showing that circGFRA1 (hsa_circ_005239, chr10:116,059,925–116,274,705), which is derived from gene GFRA1 (GDNF family receptor alpha 1), was abundantly expressed in all four PCa tumor tissues compared to normal tissues. Here, GFRA1 is linked to posterior cortical atrophy.