Research progress in hepatitis B virus covalently closed circular DNA

Xiaodong Zhang1, Yufei Wang2, Guang Yang1

  • 1Department of Gastrointestinal Cancer Biology, Liver Cancer Center, Tianjin Medical University Cancer Institute & Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, Tianjin's Clinical Research Center for Cancer, Tianjin 300060, China.

Cancer Biology & Medicine
|December 21, 2021
PubMed

Insights

Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) drives viral replication and liver cancer. This review details HBV cccDNA mechanisms, epigenetic modulation, and novel therapeutic strategies for its elimination.

Area of Science:

  • Hepatology
  • Virology
  • Molecular Biology

Background:

  • Hepatitis B virus (HBV) infection is a major global health concern.
  • HBV covalently closed circular DNA (cccDNA) is essential for viral replication and a persistent obstacle to cure.
  • Epigenetic modulation of HBV cccDNA by host factors is linked to hepatocellular carcinoma (HCC) development.

Purpose of the Study:

  • To review recent advances in understanding HBV cccDNA.
  • To discuss factors influencing HBV cccDNA epigenetic modulation.
  • To explore therapeutic strategies targeting HBV cccDNA.

Main Methods:

  • Literature review of HBV cccDNA research.
  • Analysis of host factors and epigenetic mechanisms.
  • Discussion of serological biomarkers and drug effects.

Main Results:

  • HBV X protein (HBx) modulates host epigenetic factors, linking cccDNA to hepatocarcinogenesis.
  • Measurable serological biomarkers indicate cccDNA transcription.
  • Current anti-HBV drugs have limited effects on cccDNA.

Conclusions:

  • HBV cccDNA remains a significant challenge in HBV infection and HCC.
  • Understanding cccDNA epigenetic modulation is crucial for developing effective therapies.
  • Targeting HBV cccDNA offers a promising strategy for HBV cure and liver disease management.

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