Anti-HBV drugs suppress the growth of HBV-related hepatoma cells via down-regulation of hepatitis B virus X protein

Cancer Lett. 2017 Apr 28:392:94-104. doi: 10.1016/j.canlet.2017.02.003. Epub 2017 Feb 9.

Abstract

Chronic infection of hepatitis B virus (HBV) is closely associated with the development of hepatocellular carcinoma (HCC). Meta-analyses show that adjuvant anti-HBV therapy is effective for HBV-related HCC patients in clinical. However, the significance that anti-HBV drugs depress HCC is poorly understood. Here, we investigated the effects of telbivudine (LdT), entecavir (ETV) and interferon-α2b (IFN-α2b) on HBV-related HCC. Our data showed that the treatment with the drugs significantly suppressed the growth of HBV-expressing hepatoma cells in vitro and in vivo, but failed to work in HBV-free liver cells. We present the hypothesis that HBx may be involved in the event. As expected, we observed that the expression of HBx was down-regulated by the agents. Meanwhile, the expression of HBx downstream factors was significantly down-regulated. Interestingly, LdT, ETV and IFN-α2b lost the anti-proliferation effects on HBV-related hepatoma cells when the cells were treated with HBx siRNA. Moreover, combination of those drugs enhanced the anti-proliferation effects. In conclusion, LdT, ETV and IFN-α2b suppress the growth of HBV-related HCC through down-regulation of HBx. Our finding provides new insights into the mechanisms of anti-HBV drugs in HCC therapy.

Keywords: ETV; HBx; HCC; IFN-α2b; LdT.

MeSH terms

  • Animals
  • Antiviral Agents / pharmacology*
  • Carcinoma, Hepatocellular / drug therapy*
  • Carcinoma, Hepatocellular / pathology
  • Carcinoma, Hepatocellular / virology
  • Cell Proliferation / drug effects*
  • DNA Replication / drug effects
  • DNA, Viral / biosynthesis
  • DNA, Viral / drug effects
  • Dose-Response Relationship, Drug
  • Down-Regulation
  • Drug Therapy, Combination
  • Guanine / analogs & derivatives*
  • Guanine / pharmacology
  • Hep G2 Cells
  • Hepatitis B Surface Antigens / genetics
  • Hepatitis B Surface Antigens / metabolism
  • Hepatitis B e Antigens / genetics
  • Hepatitis B e Antigens / metabolism
  • Hepatitis B virus / drug effects*
  • Hepatitis B virus / genetics
  • Hepatitis B virus / metabolism
  • Hepatitis B, Chronic / complications
  • Hepatitis B, Chronic / drug therapy*
  • Hepatitis B, Chronic / virology
  • Humans
  • Interferon alpha-2
  • Interferon-alpha / pharmacology*
  • Liver Neoplasms / drug therapy*
  • Liver Neoplasms / pathology
  • Liver Neoplasms / virology
  • Male
  • Mice, Inbred BALB C
  • Mice, Nude
  • Mice, Transgenic
  • RNA Interference
  • Recombinant Proteins / pharmacology
  • Telbivudine
  • Thymidine / analogs & derivatives*
  • Thymidine / pharmacology
  • Time Factors
  • Trans-Activators / metabolism*
  • Transfection
  • Tumor Burden / drug effects
  • Viral Regulatory and Accessory Proteins
  • Virus Replication / drug effects
  • Xenograft Model Antitumor Assays

Substances

  • Antiviral Agents
  • DNA, Viral
  • Hepatitis B Surface Antigens
  • Hepatitis B e Antigens
  • Interferon alpha-2
  • Interferon-alpha
  • Recombinant Proteins
  • Trans-Activators
  • Viral Regulatory and Accessory Proteins
  • hepatitis B virus X protein
  • Telbivudine
  • entecavir
  • Guanine
  • Thymidine