Chattaraj Arghya, Selvam T Palani
Radiological Physics and Advisory Division, Health, Safety and Environment Group, Bhabha Atomic Research Centre, Mumbai, 400085, India.
Homi Bhabha National Institute, Anushaktinagar, Mumbai, 400094, India.
Biomed Phys Eng Express. 2024 Jun 28;10(4). doi: 10.1088/2057-1976/ad57ce.
. Radiation-induced DNA damages such as Single Strand Break (SSB), Double Strand Break (DSB) and Complex DSB (cDSB) are critical aspects of radiobiology with implications in radiotherapy and radiation protection applications.. This study presents a thorough investigation into the effects of protons (0.1-100 MeV/u), helium ions (0.13-100 MeV/u) and carbon ions (0.5-480 MeV/u) on DNA of human fibroblast cells using Geant4-DNA track structure code coupled with DBSCAN algorithm and Monte Carlo Damage Simulations (MCDS) code. Geant4-DNA-based simulations consider 1m × 1m × 0.5m water box as the target to calculate energy deposition on event-by-event basis and the three-dimensional coordinates of the interaction location, and then DBSCAN algorithm is used to calculate yields of SSB, DSB and cDSB in human fibroblast cell. The study investigated the influence of Linear Energy Transfer (LET) of protons, helium ions and carbon ions on the yields of DNA damages. Influence of cellular oxygenation on DNA damage patterns is investigated using MCDS code.. The study shows that DSB and SSB yields are influenced by the LET of the particles, with distinct trends observed for different particles. The cellular oxygenation is a key factor, with anoxic cells exhibiting reduced SSB and DSB yields, underscoring the intricate relationship between cellular oxygen levels and DNA damage. The study introduced DSB/SSB ratio as an informative metric for evaluating the severity of radiation-induced DNA damage, particularly in higher LET regions.. The study highlights the importance of considering particle type, LET, and cellular oxygenation in assessing the biological effects of ionizing radiation.
辐射诱导的DNA损伤，如单链断裂（SSB）、双链断裂（DSB）和复杂双链断裂（cDSB），是放射生物学的关键方面，对放射治疗和辐射防护应用具有重要意义。本研究使用Geant4-DNA轨迹结构代码结合DBSCAN算法和蒙特卡罗损伤模拟（MCDS）代码，对质子（0.1-100 MeV/u）、氦离子（0.13-100 MeV/u）和碳离子（0.5-480 MeV/u）对人成纤维细胞DNA的影响进行了深入研究。基于Geant4-DNA的模拟将1m×1m×0.5m的水箱作为靶标，逐事件计算能量沉积以及相互作用位置的三维坐标，然后使用DBSCAN算法计算人成纤维细胞中SSB、DSB和cDSB的产额。该研究调查了质子、氦离子和碳离子的线能量转移（LET）对DNA损伤产额的影响。使用MCDS代码研究了细胞氧合对DNA损伤模式的影响。研究表明，DSB和SSB产额受粒子LET的影响，不同粒子呈现出不同的趋势。细胞氧合是一个关键因素，缺氧细胞的SSB和DSB产额降低，突出了细胞氧水平与DNA损伤之间的复杂关系。该研究引入DSB/SSB比值作为评估辐射诱导DNA损伤严重程度的信息性指标，特别是在高LET区域。该研究强调了在评估电离辐射的生物学效应时考虑粒子类型、LET和细胞氧合的重要性。
