Downregulation of cytoplasmic DNases is implicated in cytoplasmic DNA accumulation and SASP in senescent cells

Nat Commun. 2018 Mar 28;9(1):1249. doi: 10.1038/s41467-018-03555-8.


Accumulating evidence indicates that the senescence-associated secretory phenotype (SASP) contributes to many aspects of physiology and disease. Thus, controlling the SASP will have tremendous impacts on our health. However, our understanding of SASP regulation is far from complete. Here, we show that cytoplasmic accumulation of nuclear DNA plays key roles in the onset of SASP. Although both DNase2 and TREX1 rapidly remove the cytoplasmic DNA fragments emanating from the nucleus in pre-senescent cells, the expression of these DNases is downregulated in senescent cells, resulting in the cytoplasmic accumulation of nuclear DNA. This causes the aberrant activation of cGAS-STING cytoplasmic DNA sensors, provoking SASP through induction of interferon-β. Notably, the blockage of this pathway prevents SASP in senescent hepatic stellate cells, accompanied by a decline of obesity-associated hepatocellular carcinoma development in mice. These findings provide valuable new insights into the roles and mechanisms of SASP and possibilities for their control.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Carcinoma, Hepatocellular / enzymology
  • Cell Line
  • Cellular Senescence*
  • Cytoplasm / enzymology*
  • DNA Damage
  • DNA, Single-Stranded / metabolism
  • Deoxyribonucleases / metabolism*
  • Down-Regulation*
  • Exodeoxyribonucleases / metabolism
  • Hepatic Stellate Cells / enzymology
  • Humans
  • Interferon-beta / metabolism
  • Liver / enzymology
  • Liver Neoplasms / enzymology
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Microscopy, Fluorescence
  • Phenotype
  • Phosphoproteins / metabolism
  • Phosphorylation
  • RNA Interference


  • DNA, Single-Stranded
  • Phosphoproteins
  • Interferon-beta
  • Deoxyribonucleases
  • Exodeoxyribonucleases
  • three prime repair exonuclease 1
  • DNASE2 protein, human