A Dual Role of Caspase-8 in Triggering and Sensing Proliferation-Associated DNA Damage, a Key Determinant of Liver Cancer Development

Cancer Cell. 2017 Sep 11;32(3):342-359.e10. doi: 10.1016/j.ccell.2017.08.010.

Abstract

Concomitant hepatocyte apoptosis and regeneration is a hallmark of chronic liver diseases (CLDs) predisposing to hepatocellular carcinoma (HCC). Here, we mechanistically link caspase-8-dependent apoptosis to HCC development via proliferation- and replication-associated DNA damage. Proliferation-associated replication stress, DNA damage, and genetic instability are detectable in CLDs before any neoplastic changes occur. Accumulated levels of hepatocyte apoptosis determine and predict subsequent hepatocarcinogenesis. Proliferation-associated DNA damage is sensed by a complex comprising caspase-8, FADD, c-FLIP, and a kinase-dependent function of RIPK1. This platform requires a non-apoptotic function of caspase-8, but no caspase-3 or caspase-8 cleavage. It may represent a DNA damage-sensing mechanism in hepatocytes that can act via JNK and subsequent phosphorylation of the histone variant H2AX.

Keywords: DNA damage response; apoptosis; hepatocellular carcinoma; liver; replication stress.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis
  • Carcinogenesis / metabolism*
  • Carcinogenesis / pathology*
  • Carcinoma, Hepatocellular / pathology
  • Caspase 8 / metabolism*
  • Cell Proliferation
  • Cellular Senescence
  • Chronic Disease
  • Crosses, Genetic
  • DNA Damage*
  • DNA Repair
  • Fas-Associated Death Domain Protein / metabolism
  • Female
  • Genomic Instability
  • Hepatectomy
  • Hepatocytes / pathology
  • Histones / metabolism
  • Humans
  • JNK Mitogen-Activated Protein Kinases / metabolism
  • Liver / metabolism
  • Liver / pathology
  • Liver Neoplasms / enzymology*
  • Liver Neoplasms / pathology*
  • Liver Regeneration
  • Male
  • Mice
  • Myeloid Cell Leukemia Sequence 1 Protein / metabolism
  • Phosphorylation
  • Receptor-Interacting Protein Serine-Threonine Kinases / metabolism
  • Receptors, Tumor Necrosis Factor, Type I / metabolism
  • Risk Factors

Substances

  • Fadd protein, mouse
  • Fas-Associated Death Domain Protein
  • Histones
  • Mcl1 protein, mouse
  • Myeloid Cell Leukemia Sequence 1 Protein
  • Receptors, Tumor Necrosis Factor, Type I
  • gamma-H2AX protein, mouse
  • Receptor-Interacting Protein Serine-Threonine Kinases
  • Ripk1 protein, mouse
  • JNK Mitogen-Activated Protein Kinases
  • Caspase 8