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Updated: Jul 16, 2026
11:40
A Co-culture Method to Investigate the Crosstalk Between X-ray Irradiated Caco-2 Cells and PBMC
Published on: January 30, 2018
Intercellular and intracellular signaling pathways mediating ionizing radiation-induced bystander effects
Nobuyuki Hamada1, Hideki Matsumoto, Takamitsu Hara
1Department of Quantum Biology, Division of Bioregulatory Medicine, Gunma University Graduate School of Medicine, Maebashi, Japan. hamada.nobuyuki76@jaea.go.jp
Journal of Radiation Research
|March 1, 2007
Summary
Ionizing radiation triggers bystander effects in non-irradiated cells, challenging traditional radiation biology. These effects involve intercellular signaling and may offer benefits in cancer radiotherapy.
Area of Science:
- Radiobiology
- Cellular Biology
Background:
- Ionizing radiation (IR) induces biological effects in non-irradiated bystander cells.
- This phenomenon, known as the IR-induced bystander effect, challenges the paradigm that direct radiation exposure is necessary for cellular response.
- Bystander effects are observed across various experimental systems, affecting cells regardless of whether their nucleus or cytoplasm is irradiated.
Purpose of the Study:
- To review current knowledge of the IR-induced bystander effect.
- To focus on the proposed mechanisms mediating these effects.
- To discuss the potential benefits of bystander effects in cancer radiotherapy.
Main Methods:
- Review of experimental evidence on IR-induced bystander effects.
- Analysis of proposed mediating mechanisms.
- Discussion of implications for radiotherapy.
Main Results:
- Bystander cells exhibit genetic and epigenetic changes, altered gene expression, and activated signal transduction pathways.
- Mediating mechanisms include gap junction communication, soluble factors, oxidative metabolism, lipid rafts, and calcium fluxes.
- Bystander effects manifest in various biological consequences, including delayed effects in progeny.
Conclusions:
- The IR-induced bystander effect is a significant phenomenon in radiobiology.
- Understanding the mechanisms is crucial for exploring its therapeutic potential.
- Bystander effects may hold promise for enhancing cancer radiotherapy outcomes.
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