Inactivation of Aerobic and Hypoxic Cells from Three Different Cell Lines by Accelerated3He-,12C- and20Ne-Ion Beams

Furusawa, Yoshiya; Fukutsu, Kumiko; Aoki, Mizuho; Itsukaichi, Hiromi; Eguchi-Kasai, Kiyomi; Ohara, Hiroshi; Yatagai, Fumio; Kanai, Tatsuaki; Andō, Kōichi

doi:10.1667/0033-7587(2000)154[0485:ioaahc]2.0.co;2

Cited by 409 publications

(445 citation statements)

References 23 publications

Supporting

Mentioning

404

Contrasting

Order By: Relevance

“…The different track structure from X-rays or g-rays, heavy ion beams can cause dense ionization and excitation along the pathway [50]. Accordingly, high-and low-LET irradiation sources may produce qualitatively and This result almost coincides with previous studies on the same HSG cells [51]. In the other studies using different cell lines and different irradiation sources, the LET dependence of cell death was reported to have a sharp increase or a peak in LET range of 100 -120 keV/ mm C-ion irradiation [21] or 120 -300 keV/mm Ne-ion irradiation [52], which also seemed in accordance with the present study.…”

Section: Discussionsupporting

confidence: 87%

High yields of isochromatid breaks and successive formation of chromosome exchanges may lead to reproductive cell death following high-LET irradiation

Gotoh¹,

Funada

Mohri

et al. 2008

Open Life Sciences

View full text Add to dashboard Cite

To clarify the relationship between cell death and chromosomal aberrations following exposure to heavy-charged ion particles beams, exponentially growing Human Salivary Gland Tumor cells (HSG cells) were irradiated with various kinds of high energy heavy ions; 13 keV/μm carbon ions as a low-LET charged particle radiation source, 120 keV/μm carbon ions and 440 keV/μm iron ions as high-LET charged particle radiation sources. X-rays (200 kVp) were used as a reference. Reproductive cell death was evaluated by clonogenic assays, and the chromatid aberrations in G2/M phase and their repairing kinetics were analyzed by the calyculin A induced premature chromosome condensation (PCC) method. High-LET heavy-ion beams introduced much more severe and un-repairable chromatid breaks and isochromatid breaks in HSG cells than low-LET irradiation. In addition, the continuous increase of exchange aberrations after irradiation occurred in the high-LET irradiated cells. The cell death, initial production of isochromatid breaks and subsequent formation of chromosome exchange seemed to be depend similarly on LET with a maximum RBE peak around 100–200 keV/μm of LET value. Conversely, un-rejoined isochromatid breaks or chromatid breaks/gaps seemed to be less effective in reproductive cell death. These results suggest that the continuous yield of chromosome exchange aberrations induced by high-LET ionizing particles is a possible reason for the high RBE for cell death following high-LET irradiation, alongside other chromosomal aberrations additively or synergistically.

show abstract

Section: Discussionsupporting

confidence: 87%

High yields of isochromatid breaks and successive formation of chromosome exchanges may lead to reproductive cell death following high-LET irradiation

Gotoh¹,

Funada

Mohri

et al. 2008

Open Life Sciences

View full text Add to dashboard Cite

show abstract

“…a n55-7)CL585%, n58-10)CL590%, n>11)CL595%. He ions compared with 3 He ions), which was also measured and modelled by Furusawa et al [26].…”

Section: Discussionmentioning

confidence: 59%

Repair kinetic considerations in particle beam radiotherapy

Carabe‐Fernandez

Dale²,

Paganetti³

2011

BJR

View full text Add to dashboard Cite

Objectives: A second-order repair kinetics model is developed to predict damage repair rates following low or high linear energy transfer (LET) irradiations and to assess the amount of unrepairable damage produced by such radiations. The model is a further development of an earlier version designed to test if low-LET radiation repair processes could be quantified in terms of second-order kinetics. The newer version allows calculation of both the repair rate of the proportion of DNA damages that repair according to secondorder kinetics and the proportion of DNA damages that do not repair. Methods: The original and present models are intercompared in terms of their goodness-of-fit to a number of data sets obtained from different ion beams. The analysis demonstrates that the present model provides a better fit to the data in all cases studied. Results: The proportions of unrepairable damage created by radiations of different LET predicted by the new model correspond well with previous studies on the increased effectiveness of high-LET radiations in inducing reproductive cell death. The results show that the original model may underestimate the proportion of unrepaired damage at any given time after its creation as well as failing to predict very slow or unrepairable damage components, which may result from high-LET irradiation. Conclusion: It is suggested that the second-order model presented here offers a more realistic view of the patterns of repair in cell lines or tissues exposed to high-LET radiation. investigations provide evidence that radiations of different linear energy transfer (LET) produce different types of DNA damage and that a larger proportion of complex damage is being created by higher LET. There is also evidence that different types of DNA damage are associated with different repair rates, with more complex damage taking longer to repair (if at all) [3,4]. It has been reported [5,6] that highly complex DNA breaks imply in some cases such a massive loss of DNA coding that the chances of correct repair are very low.For a given particle type, the relative biological effectiveness (RBE) increases with LET until reaching a maximum and then decreases. Belli et al [7] have recently studied the repair characteristics of double-strand breaks (DSBs) produced by radiations of different LET, arriving at the conclusion that the increase in RBE for cell inactivation with LET might be related to the increasing proportion of unrepaired DSB rather than the proportion of induced DSB. A similar conclusion was reached by Barendsen [1,8,9], who studied the LET dependency of different types of DNA strand breaks and suggested different candidates of DNA damage to explain cell inactivation. Other authors also have found a correspondence between unrepaired DNA strand breaks and cell lethality (e.g. Ritter et al [10], Goodhead et al [11] and more recently Eguchi-Kasai et al [12]), but none of them provided information on the specific nature of the unrepairable DNA strand breaks.In practical terms, DNA DSBs with very slow...

show abstract

“…The RBE that has been used for carbon-ion radiotherapy at NIRS was originally defined for an in vitro endpoint: survival fraction S = 10% for human salivary gland (HSG) cells, 24 as…”

Section: Rbe Modifificationmentioning

confidence: 99%

Influence of nuclear interactions in polyethylene range compensators for carbon-ion radiotherapy

Kanematsu¹,

Koba²,

Ogata³

et al. 2014

Med. Phys.

View full text Add to dashboard Cite

Purpose: A recent study revealed that polyethylene (PE) would cause extra carbon-ion attenuation per range shift by 0.45%/cm due to compositional differences in nuclear interactions. The present study aims to assess the influence of PE range compensators on tumor dose in carbon-ion radiotherapy.Methods: Carbon-ion radiation was modeled to be composed of primary carbon ions and secondary particles, for each of which the dose and the relative biological effectiveness (RBE) were estimated at a tumor depth in the middle of spread-out Bragg peak. Assuming exponential behavior for attenuation and yield of these components with depth, the PE effect on dose was calculated for clinical carbon-ion beams and was partly tested by experiment. The two-component model was integrated into a treatment-planning system and the PE effect was estimated in two clinical cases. Results:The attenuation per range shift by PE was 0.1%-0.3%/cm in dose and 0.2%-0.4%/cm in RBEweighted dose, depending on energy and range-modulation width. This translates into reduction of RBEweighted dose by up to 3% in extreme cases. In the treatment-planning study, however, the effect on RBEweighted dose to tumor was typically within 1% reduction. Conclusions:The extra attenuation of primary carbon ions in PE was partly compensated by increased secondary particles for tumor dose. In practical situations, the PE range compensators would normally cause only marginal errors as compared to intrinsic uncertainties in treatment planning, patient setup, beam delivery, and clinical response.

show abstract

Inactivation of Aerobic and Hypoxic Cells from Three Different Cell Lines by Accelerated³He-,¹²C- and²⁰Ne-Ion Beams

Cited by 409 publications

References 23 publications

High yields of isochromatid breaks and successive formation of chromosome exchanges may lead to reproductive cell death following high-LET irradiation

High yields of isochromatid breaks and successive formation of chromosome exchanges may lead to reproductive cell death following high-LET irradiation

Repair kinetic considerations in particle beam radiotherapy

Influence of nuclear interactions in polyethylene range compensators for carbon-ion radiotherapy

Contact Info

Product

Resources

About