Research advances in hepatitis B virus genome integration

HBV DNA integration （iDNA） is the core barrier that must be overcome to achieve functional cure for chronic hepatitis B （CHB） and to prevent the occurrence of hepatocellular carcinoma （HCC）. During reverse transcription， 5%　—　10% of viral genomes are converted into double-stranded linear DNA that is randomly inserted into host chromosomes， generating stable iDNA and continuously producing HBsAg， thereby driving B- and T-cell immune exhaustion and locking the host in an immune-tolerant state. The process of iDNA runs throughout the entire natural history of HBV infection， and the viral enhancers it carries can promote clonal hyperplasia of indeterminate potential， accumulate pre-neoplastic mutations， and ultimately lead to HCC. Although long-term nucleos（t）ide analog or interferon therapy can suppress viral replication and reduce the formation of new integrations， existing therapies still fail to eliminate existing iDNA. Therefore， there is an urgent need for innovative strategies that can precisely target integration breakpoints， epigenetically silence iDNA， or eradicate integrated clones， so as to significantly increase the functional cure rate of CHB and fundamentally reduce the risk of HCC.