Oxidative Stress Facilitates IFN-γ-Induced Mimic Extracellular Trap Cell Death in A549 Lung Epithelial Cancer Cells

PLoS One. 2016 Aug 30;11(8):e0162157. doi: 10.1371/journal.pone.0162157. eCollection 2016.

Abstract

We previously demonstrated that IFN-γ induces an autophagy-regulated mimic extracellular trap cell death (ETosis) in A549 human lung cancer cells. Regarding reactive oxygen species (ROS) are involved in ETosis, this study investigated the role of oxidative stress. After IFN-γ stimulation, a necrosis-like cell death mimic ETosis occurred accompanied by the inhibition of cell growth, aberrant nuclear staining, and nucleosome release. ROS were generated in a time-dependent manner with an increase in NADPH oxidase component protein expression. STAT1-mediated IFN regulatory factor-1 activation was essential for upregulating ROS production. By genetically silencing p47phox, IFN-γ-induced ROS and mimic ETosis were significantly attenuated. This mechanistic study indicated that ROS may mediate DNA damage followed by histone H3 citrullination. Furthermore, ROS promoted IFN-γ-induced mimic ETosis in cooperation with autophagy. These findings further demonstrate that ROS regulates IFN-γ-induced mimic ETosis in lung epithelial malignancy.

MeSH terms

  • A549 Cells
  • Cell Survival / drug effects
  • Extracellular Traps / metabolism*
  • Humans
  • Interferon-gamma / pharmacology*
  • Lung Neoplasms / metabolism*
  • NADPH Oxidases / metabolism
  • Oxidative Stress
  • Reactive Oxygen Species / metabolism*
  • STAT1 Transcription Factor / metabolism

Substances

  • Reactive Oxygen Species
  • STAT1 Transcription Factor
  • STAT1 protein, human
  • Interferon-gamma
  • NADPH Oxidases

Grants and funding

This work was supported by grant NHRI-EX102-9917NC from the National Health Research Institutes, Taiwan and grant MOST100-2320-B-006-009-MY3 from the Ministry of Science and Technology, Taiwan. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.