Background/aim: Pre-clinical studies have shown that irradiation with electrons at an ultra-high dose-rate (FLASH) spares normal tissue while maintaining tumor control. However, most in vitro experiments with protons have been conducted using a non-clinical irradiation system in normoxia alone. This study evaluated the biological response of non-tumor and tumor cells at different oxygen concentrations irradiated with ultra-high dose-rate protons using a clinical system and compared it with the conventional dose rate (CONV).
Materials And Methods: Non-tumor cells (V79) and tumor cells (U-251 and A549) were irradiated with 230 MeV protons at a dose rate of >50 Gy/s or 0.1 Gy/s under normoxic or hypoxic (<2%) conditions. The surviving fraction was analyzed using a clonogenic cell survival assay.
Results: No significant difference in the survival of non-tumor or tumor cells irradiated with FLASH was observed under normoxia or hypoxia compared to the CONV.
Conclusion: Proton irradiation at a dose rate above 40 Gy/s, the FLASH dose rate, did not induce a sparing effect on either non-tumor or tumor cells under the conditions examined. Further studies are required on the influence of various factors on cell survival after FLASH irradiation.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.21873/anticanres.17109 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Monte Carlo in the mechanistic modelling of the FLASH effect: a review.
Phys Med Biol
January 2025
Physics, The University of Western Australia, 35 Stirling Highway, Mailbag M013, WA 6009, Perth, 6009, AUSTRALIA.
FLASH radiotherapy employs ultra-high dose rates of >40 Gy/s, which may reduce normal tissue complication as compared to conventional dose rate treatments, while still ensuring the same level of tumour control. The potential benefit this can offer to patients has been the cause of great interest within the radiation oncology community, but this has not translated to a direct understanding of the FLASH effect. The oxygen depletion and inter-track interaction hypotheses are currently the leading explanations as to the mechanisms behind FLASH, but these are still not well understood, with many questions remaining about the exact underpinnings of FLASH and the treatment parameters required to optimally induce it.
View Article and Find Full Text PDFUltra-High Dose Rate Helium Ion Beams: Minimizing Brain Tissue Damage while Preserving Tumor Control.
Mol Cancer Ther
December 2024
National Center for Tumor Diseases, Heidelberg, Germany.
Ultra-high dose rate radiotherapy with electrons and protons has shown potential for cancer treatment by effectively targeting tumors while sparing healthy tissues (FLASH effect). This study aimed to investigate the potential FLASH sparing effect of ultra-high-dose rate helium ion irradiation, focusing on acute brain injury and subcutaneous tumor response in a preclinical in vivo setting. Raster-scanned helium ion beams were used to compare the effects of standard dose rate (SDR at 0.
View Article and Find Full Text PDFUltra-high dose rate (FLASH) carbon ion irradiation inhibited immune suppressive protein expression on Pan02 cell line.
J Radiat Res
December 2024
Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
Recently, ultra-high dose rate (> 40 Gy/s, uHDR; FLASH) radiation therapy (RT) has attracted interest, because the FLASH effect that is, while a cell-killing effect on cancer cells remains, the damage to normal tissue could be spared has been reported. This study aimed to compare the immune-related protein expression on cancer cells after γ-ray, conventionally used dose rate (Conv) carbon ion (C-ion), and uHDR C-ion. B16F10 murine melanoma and Pan02 murine pancreas cancer were irradiated with γ-ray at Osaka University and with C-ion at Osaka HIMAK.
View Article and Find Full Text PDFRapid Sterilization of Clinical Apheresis Blood Products using Ultra-High Dose Rate Radiation.
bioRxiv
December 2024
Stanford Blood Center, Stanford Health Care, Stanford, California, USA.
Background And Objectives: Apheresis platelets products and plasma are essential for medical interventions, but both still have inherent risks associated with contamination and viral transmission. Platelet products are vulnerable to bacterial contamination due to storage conditions, while plasma requires extensive screening to minimize virus transmission risks. Here we investigate rapid irradiation to sterilizing doses for bacteria and viruses as an innovative pathogen reduction technology.
View Article and Find Full Text PDFA 2D detector array for relative dosimetry and beam steering for FLASH radiotherapy with electrons.
Med Phys
December 2024
Dosimetry for Radiotherapy, Physikalisch-Technische Bundesanstalt, Braunschweig, 38116, Germany.
Background: FLASH radiotherapy is an emerging treatment modality using ultra-high dose rate beams. Much effort has been made to develop suitable dosimeters for reference dosimetry, yet the spatial beam characteristics must also be characterized to enable computerized treatment planning, as well as quality control and service of a treatment delivery device. In conventional radiation therapy, this is commonly achieved by beam profile scans in a water phantom using a point detector.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!