In an illustrative study by Sung et al., they noted that HBV integration was more common in carcinomatous versus adjacent normal liver tissue (86.4% vs. 30.7%) with integration sites occurring at known cancer-related genes including telomerase reverse transcriptase (TERT), mixed lineage leukaemia 4 (MLL4) and cyclin E1 (CCNE1) [22]. This evidence concerns the gene CCNE1 and cancer.