GFRA1 and neoplasm: 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.