For example, circ-0000502, circ-PRMT5, circ-SPINK1, circ-0103552 and ciRS-7 were reported to be promising prognostic biomarkers in osteosarcoma [31], bladder cancer [32], hepatocellular carcinoma [33], breast cancer [34] and colorectal cancer [35], respectively. The gene discussed is PRMT5; the disease is hepatocellular carcinoma.