LRIG3 and hepatocellular carcinoma: Except for HCC tissues and cell lines, several circRNAs upregulated in plasma, serum, and exosomes (serum-derived or cancer cell-derived) were identified as potent non-invasive prognostic biomarkers by KM analysis, such as circTMEM45A, circ-LRIG3, circUHRF1, circRNA-100,338, circPTGR1 (34, 41, 42, 57, 78).