Monte Carlo simulation-based analysis of cell damage by 9C-ion decay products
10.3760/cma.j.cn112271-20230817-00050
- VernacularTitle:基于蒙特卡罗模拟的 9C重离子衰变产物对细胞损伤的分析
- Author:
Yi ZHANG
1
;
Shihu YOU
;
Yuanqiang LUO
;
Zhiyong WANG
;
Congfeng XU
;
Haijie JIN
;
Haojia ZHANG
;
Wei HONG
;
Jiaying GAN
;
Yinxiang HU
Author Information
1. 贵州医科大学附属医院肿瘤科，贵阳 550024
- Keywords:
9C-ion;
Delayed particle;
Monte-Carlo simulation;
Cell surviving fraction
- From:
Chinese Journal of Radiological Medicine and Protection
2024;44(5):361-366
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the radiological damage to cells induced by the delayed particles of 9C-ions for heavy ion therapy, as well as the microdosimetric distribution and biological effects of these particles on a single model of V79 Chinese hamster lung cells. Methods:The Monte Carlo program was employed to simulate the endonuclear absorbed doses of α particles with various energies (3-10 MeV) transported in cells (cell radius RC = 10 μm, nucleus radius RN = 5 μm). Then, the result were compared with the S values ( SN←N, SN←Cy, and SN←CS) derived using the medical internal radiation dose (MIRD) method to demonstrate the feasibility of Monte Carlo simulations. Finally, the energy deposition of the delayed particles of 9C-ions generated at three sites (i.e., on the surface and in the cytoplasm and nucleus of the V79 cell model) during their transport in targets was simulated, and the result ing cell surviving fraction was analyzed. Results:Monte Carlo and MIRD method yielded differences in S values of 1.91%-4.95% for SN←N (nucleus to nucleus), 1.48%-5.11% for SN←Cy (cytoplasm to nucleus), and -1.99% to 0.80% for SN←CS(surface to nucleus), indicating highly consistent S values derived using both method(differences < 6%). When a 9C-ion decayed on the surface of the V79 cell model and the produced secondary particles entered the cell, the average endonuclear absorbed dose was 10 -2 Gy orders of magnitude, with a cell surviving fraction of about 88%. In the case where decay occurred in the cytoplasm, the cell surviving fraction was about 80%. However, when the 9C ion decayed in the nucleus, α particles had short ranges and deposited most of their energy in the cell (mean endonuclear absorbed dose: 0.1 Gy). In this case, severe cell damage was induced, with the cell surviving fraction reducing to about 53%. Conclusions:9C-ions emit secondary charged particles due to decay, among which α particles cause great damage to cells when entering the nucleus and trigger evident biological effects.
