[Significance of radiation-induced bystander effects in radiation therapy].
[Significance of radiation-induced bystander effects in radiation therapy].
复制标题
[辐射治疗中辐射引起的旁观者效应的意义]。
DOI：
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发表时间：
2014
期刊：
影响因子：
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通讯作者：
Masao Suzuki
中科院分区：
文献类型：
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作者：
Masao Suzuki
自1994年以来，日本放射医学综合研究所利用千叶重离子医用加速器（HIMAC）产生的碳离子束开展了I/II期临床研究和放射治疗。现在我们在HIMAC建造了新的先进碳离子治疗设施，采用了笔形束三维快速点扫描系统。在高传能线密度重离子的基础生物学研究领域，有一些关于暴露于来自²³⁸Pu的α粒子或氦离子微束后的旁观者效应的报道。然而，只有有限的研究考察了暴露于比氦更重的不同离子种类（如碳离子）后的旁观者效应。我们一直在研究用HIMAC碳离子照射的正常人类细胞和人类肿瘤细胞中的旁观者细胞反应。在含有野生型P53基因的细胞中观察到旁观者细胞杀伤效应，但在P53突变细胞中未观察到。此外，通过使用间隙连接介导的细胞间通讯的特异性抑制剂处理，观察到的旁观者效应受到抑制。有明确证据表明，碳离子照射通过间隙连接介导的旁观者效应能够增强野生型P53基因细胞的杀伤作用。
Since 1994, a Phase I/II clinical study and radiotherapy have carried out using carbon-ion beams produced with the Heavy Ion Medical Accelerator in Chiba (HIMAC) at National Institute of Radiological Sciences. Now we constructed the new treatment facility for the advanced carbon-ion therapy at HIMAC applying a 3D fast spot scanning system with pencil beams. In the field of fundamental biological studies for high-LET heavy ions, there are some reports regarding bystander effects after exposure to alpha particles derived from 238Pu or He-ion microbeams. However, only limited sets of studies have examined bystander effects after exposure to different ion species heavier than helium, such as carbon ions. We have been investigating bystander cellular responses in both normal human and human tumor cells irradiated with the HIMAC carbon ions. Bystander cell-killing effect was observed in the cells harboring wild-type P53 gene, but not in the P53-mutated cells. Moreover, observed bystander effect was suppressed by treating with a specific inhibitor of gap-junction mediated cell-cell communication. There is clear evidence that the carbon-ion irradiation enables the enhanced cell killing in cells with wild-type P53 gene via gap-junction mediated bystander effect.