Chew Ming Tsuey, Bradley David A, Suzuki Masao, Matsufuji Naruhiro, Murakami Takeshi, Jones Bleddyn, Nisbet Andrew
Sunway University, School of Healthcare and Health Sciences, Centre for Biomedical Physics, No. 5, Jalan Universiti, Bandar Sunway, Petaling Jaya, Selangor, Malaysia.
Department of Physics, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, UK.
J Radiat Res. 2019 Mar 1;60(2):178-188. doi: 10.1093/jrr/rry099.
The effects of the charged ion species 4He, 12C and 20Ne on glioblastoma multiforme (GBM) T98G, U87 and LN18 cell lines were compared with the effects of 200 kVp X-rays (1.7 keV/μm). These cell lines have different genetic profiles. Individual GBM relative biological effectiveness (RBE) was estimated in two ways: the RBE10 at 10% survival fraction and the RBE2Gy after 2 Gy doses. The linear quadratic model radiosensitivity parameters α and β and the α/β ratio of each ion type were determined as a function of LET. Mono-energetic 4He, 12C and 20Ne ions were generated by the Heavy Ion Medical Accelerator at the National Institute of Radiological Sciences in Chiba, Japan. Colony-formation assays were used to evaluate the survival fractions. The LET of the various ions used ranged from 2.3 to 100 keV/μm (covering the depth-dose plateau region to clinically relevant LET at the Bragg peak). For U87 and LN18, the RBE10 increased with LET and peaked at 85 keV/μm, whereas T98G peaked at 100 keV/μm. All three GBM α parameters peaked at 100 keV/μm. There is a statistically significant difference between the three GBM RBE10 values, except at 100 keV/μm (P < 0.01), and a statistically significant difference between the α values of the GBM cell lines, except at 85 and 100 keV/μm. The biological response varied depending on the GBM cell lines and on the ions used.
将带电离子种类4He、12C和20Ne对多形性胶质母细胞瘤（GBM）T98G、U87和LN18细胞系的影响与200 kVp X射线（1.7 keV/μm）的影响进行了比较。这些细胞系具有不同的基因谱。通过两种方式估计个体GBM相对生物效能（RBE）：10%存活分数时的RBE10和2 Gy剂量后的RBE2Gy。确定了每种离子类型的线性二次模型放射敏感性参数α和β以及α/β比值与传能线密度（LET）的函数关系。单能4He、12C和20Ne离子由日本千叶国立放射科学研究所的重离子医学加速器产生。采用集落形成试验评估存活分数。所使用的各种离子的LET范围为2.3至100 keV/μm（涵盖深度剂量坪区至布拉格峰处临床相关的LET）。对于U87和LN18，RBE10随LET增加，并在85 keV/μm时达到峰值，而T98G在100 keV/μm时达到峰值。所有三种GBM的α参数均在100 keV/μm时达到峰值。除了在100 keV/μm时，三种GBM的RBE10值之间存在统计学显著差异（P < 0.01），并且除了在85和100 keV/μm时，GBM细胞系的α值之间存在统计学显著差异。生物学反应因GBM细胞系和所使用的离子而异。
