Dose-dependent Changes After Proton and Photon Irradiation in a Zebrafish Model

Anticancer Res. 2020 Nov;40(11):6123-6135. doi: 10.21873/anticanres.14633.

Abstract

Background/aim: The importance of hadron therapy in the cancer management is growing. We aimed to refine the biological effect detection using a vertebrate model.

Materials and methods: Embryos at 24 and 72 h postfertilization were irradiated at the entrance plateau and the mid spread-out Bragg peak of a 150 MeV proton beam and with reference photons. Radiation-induced DNA double-strand breaks (DSB) and histopathological changes of the eye, muscles and brain were evaluated; deterioration of specific organs (eye, yolk sac, body) was measured.

Results: More and longer-lasting DSBs occurred in eye and muscle cells due to proton versus photon beams, albeit in different numbers. Edema, necrosis and tissue disorganization, (especially in the eye) were observed. Dose-dependent morphological deteriorations were detected at ≥10 Gy dose levels, with relative biological effectiveness between 0.99±0.07 (length) and 1.12±0.19 (eye).

Conclusion: Quantitative assessment of radiation induced changes in zebrafish embryos proved to be beneficial for the radiobiological characterization of proton beams.

Keywords: DNA-DSB; Proton; histological changes; morphological malformations; photon; zebrafish embryo model.

MeSH terms

  • Animals
  • Brain / radiation effects
  • DNA Damage
  • Disease Models, Animal
  • Dose-Response Relationship, Radiation
  • Embryo, Nonmammalian / radiation effects
  • Eye / pathology
  • Eye / radiation effects
  • Kinetics
  • Organ Size / radiation effects
  • Photons*
  • Protons*
  • Relative Biological Effectiveness
  • Yolk Sac / pathology
  • Yolk Sac / radiation effects
  • Zebrafish / embryology
  • Zebrafish / physiology*

Substances

  • Protons