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Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death
09:18

Identification of Intracellular Signaling Events Induced in Viable Cells by Interaction with Neighboring Cells Undergoing Apoptotic Cell Death

Published on: December 27, 2016

Clustering of apoptotic cells via bystander killing by peroxides

K Reznikov1, L Kolesnikova, A Pramanik

  • 1Experimental Alcohol and Drug Addiction Research Section, Department of Clinical Neuroscience and. Department of Medical Biochemistry and Biophysics, Karolinska Institute S-171 76, Stockholm, Sweden.

FASEB Journal : Official Publication of the Federation of American Societies for Experimental Biology
|September 7, 2000
PubMed

Insights

Apoptotic cells can kill nearby healthy cells, a process called bystander killing, which may involve hydrogen peroxide signals. This cell death mechanism is not dependent on p53 and has implications for cancer therapies.

Area of Science:

  • Cell Biology
  • Biochemistry
  • Pathology

Background:

  • Clustering of apoptotic cells suggests bystander killing, where dying cells harm neighbors.
  • This process may involve unidentified chemical signals, independent of gap junction communication.

Purpose of the Study:

  • To investigate the mechanism of apoptotic cell clustering and bystander killing.
  • To determine the role of hydrogen peroxide and p53 in this phenomenon.

Main Methods:

  • Induction of apoptosis in cell monolayers via serum deprivation or p53 transfection.
  • Observation of apoptotic cell clustering in vitro.
  • Assessment of the effect of catalase (peroxide scavenger) on bystander killing.

Main Results:

  • Apoptotic cell clusters formed spontaneously and were induced by primary apoptotic cells.
  • Catalase significantly suppressed bystander killing, identifying hydrogen peroxide as a key death signal.
  • Clustering occurred similarly regardless of p53 expression, indicating no specific p53 role in bystander killing.

Conclusions:

  • Hydrogen peroxide emitted by apoptotic cells mediates bystander killing and cell clustering.
  • This peroxide-mediated bystander killing may contribute to tissue injury in various pathologies.
  • Understanding this mechanism is relevant for cancer therapies like chemotherapy, gamma-ray, and gene therapy.

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