Hepatitis B virus X protein promotes CREB-mediated activation of miR-3188 and Notch signaling in hepatocellular carcinoma

Cell Death Differ. 2017 Sep;24(9):1577-1587. doi: 10.1038/cdd.2017.87. Epub 2017 Jun 2.

Abstract

Familiar clustering of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) has been frequently reported. However, limited information is available about the underlying molecular mechanisms in HBV-related HCC patients with family history of HCC. In our previous study, Agilent miRNA Base 16.0 microarray showed miRNA profiles of the plasma of HBV-related HCC patients who had a family history of HCC. This study aims to explore the expression, function, and mechanisms of miR-3188 in HCC that might provide novel insights into the role of family history on the risk of HCC. The expression levels of miR-3188 were markedly overexpressed in HCC tissues, HBV transgenic mice, and HepG2.215 cells. We knocked out miR-3188 in HCC cell lines using the CRISPR/Cas9 system, and demonstrated that miR-3188 knockout (KO) suppressed cell growth, migration, and invasion, and inhibited xenografts tumor growth in nude mice. Next, we determined that miR-3188 KO exerts antitumor functions by directly repressing ZHX2. It has been reported that HBV X protein (HBx) plays a critical role in HBV-related HCC, promoting CREB-mediated activation of miR-3188 and activation of Notch signaling through repressing ZHX2. Finally, we verified that ZHX2 functions as a transcriptional repressor to Notch1 via interaction with NF-YA. Our data demonstrate that the HBx-miR-3188-ZHX2-Notch1 signaling pathway plays an important role in the pathogenesis and progression of HBV-related HCC with family history of HCC. These findings have important implications for identifying new therapeutic targets in HBV-related HCC.

MeSH terms

  • Animals
  • Carcinoma, Hepatocellular / genetics
  • Carcinoma, Hepatocellular / metabolism*
  • Chromatin Immunoprecipitation
  • Gene Expression Regulation, Neoplastic / genetics
  • Gene Expression Regulation, Neoplastic / physiology
  • Hep G2 Cells
  • Humans
  • In Vitro Techniques
  • Liver Neoplasms / genetics
  • Liver Neoplasms / metabolism*
  • Mice
  • Mice, Knockout
  • Mice, Nude
  • Mice, Transgenic
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Receptors, Notch / genetics
  • Receptors, Notch / metabolism*
  • Signal Transduction / genetics
  • Signal Transduction / physiology
  • Trans-Activators / genetics
  • Trans-Activators / metabolism*
  • Viral Regulatory and Accessory Proteins

Substances

  • MIRN3189 microRNA, human
  • MicroRNAs
  • Receptors, Notch
  • Trans-Activators
  • Viral Regulatory and Accessory Proteins
  • hepatitis B virus X protein