Antiprotons: effects on biological matter and evaluation as a novel radiotherapy

反质子：对生物物质的影响以及作为新型放射疗法的评估

基本信息

批准号：
EP/H017844/1
负责人：
David Timson
金额：
$ 2.47万
依托单位：
Queen's University Belfast
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2009
资助国家：
英国
起止时间：
2009 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=EP%2FH017844%2F1
关键词：
Antiprotons effects biological matter evaluation

项目摘要

After surgery, radiation treatments are the most widely used and successful way to cure cancers. However, modern radiotherapy plans often cause severe side-effects to the patient and the overall success rate is still only moderate. Therefore there is a need to research new ways of delivering radiotherapies in order to inform and improve new treatments in the future.Radiotherapy works by killing cancer cells - usually by breaking the DNA in those cells. If the damage is so severe that the cells cannot repair it, the cells die. A lot of the research into radiotherapy is aimed at understanding how cells respond to radiations of different types and doses.One reason why radiotherapy results in side-effects is because healthy cells are damaged, or killed, as well as cancerous ones. Therefore considerable efforts have been made to minimize these effects and to focus the destructive power of radiation on tumour cells. This has been achieved, to some extent, with X-rays by irradiating the patient from multiple external sites. An alternative, and very promising, approach is the use of ion beams in place of x-rays. There are already numerous proton treatment facilities worldwide (including one in the UK) and centres using heavier ions (eg carbon) are now being brought into operation.The big advantage of ion beams is due to the way they deposit their energy in tissue. When an X-ray beam enters a person, energy is deposited immediately upon entry, thus causing damage. In contrast, ion beams can pass several centimeters through tissue before depositing the bulk of their energy. By manipulation of the physical properties of the ion beam, the depth at which ion beams deposit their energy can be controlled and made to correspond to the site of the tumour. Thus the bulk of this type of radiation's destructive power is concentrated in the cells which we wish to destroy. The results from ion beam irradiation are impressive, with improved clear-up rates and decreased side-effects.A further improvement on ion beams, may be to use antiprotons. Antiprotons will be familiar to any reader of science fiction - usually as the means of propulsion of interstellar starships or in a fearsome and destructive weapons systems. However, antiprotons can be produced here on earth, contained, controlled and used in experiments. Like their regular matter counterparts, protons, they can pass through material for several centimeters before depositing their energy. Their potential advantage arises from the fact that when an antiproton meets a proton, the two particles annihilate each other (according to Einstein's famous equation E=mc2) releasing lots of energy.A group of scientists at the European Centre for Nuclear Research (CERN) in Switzerland have begun experiments to see if antiprotons can be used in cancer therapies. This group (the ACE collaboration) have shown that antiprotons kill cells approximately four time better than protons. However, before antiprotons can be considered a viable possibility in cancer radiotherapy, considerable extra scientific work is required.In 2008, the applicants joined the ACE collaboration and carried out an experiment at CERN to investigate the effects of antiprotons on cultured human cells. They showed that antiprotons cause damage to the DNA in these cells and that the more antiprotons the cells are exposed to, the more DNA damage is caused. In addition, they demonstrated that media from irradiated cells can cause DNA damage responses in non-irradiated cells. This phenomenon, the so-called bystander effect, is well documented with other types of radiation, but has not previously been shown with antiproton irradiation.The applicants now seek funding to return to CERN in autumn 2009, in order to continue these experiments. This year they hope to learn more about the bystander effect resulting from antiproton irradiation, including quantifying the magnitude of these effects.

手术后，放射治疗是治愈癌症的最广泛使用和成功的方法。但是，现代放射治疗计划通常会对患者造成严重的副作用，并且总体成功率仍然只是中等的。因此，有必要研究提供放射疗法的新方法，以便将来告知和改善新的治疗方法。放射疗法通过杀死癌细胞而起作用 - 通常是通过破坏这些细胞中的DNA。如果损伤是如此严重以至于细胞无法修复它，则细胞死亡。对放射疗法的许多研究旨在了解细胞对不同类型和剂量的辐射的反应。放射疗法会导致副作用的原因是因为健康细胞被损害或杀死，以及癌性。因此，已经做出了大量努力，以最大程度地减少这些影响并集中辐射对肿瘤细胞的破坏力。在某种程度上，通过从多个外部部位照射患者，在某种程度上实现了这一点。一种替代性且非常有前途的方法是使用离子束代替X射线。现在已经有许多质子治疗设施（包括在英国的一个），现在使用较重离子（例如碳）正在运行中的中心。离子束的最大优势是由于它们将能量沉积在组织中的方式。当X射线光束进入一个人时，进入时会立即沉积能量，从而造成损坏。相比之下，离子束可以在沉积大部分能量之前将几厘米穿过组织。通过操纵离子束的物理特性，可以控制离子束沉积其能量的深度，并使其与肿瘤部位相对应。因此，这种辐射的大部分破坏力集中在我们希望销毁的细胞中。离子束照射的结果令人印象深刻，清除率提高并降低了副作用。离子束进一步改善，可能是使用抗磷脂。任何科幻小说的读者都会熟悉抗逆客 - 通常是推进星际飞船或可怕和破坏性武器系统的手段。但是，可以在地球上产生抗抗原子，其中包含，控制和在实验中使用。就像质子的常规物质对应物一样，它们可以在沉积能量之前通过材料几厘米。它们的潜在优势源于以下事实：当抗蛋白质遇到质子时，两个颗粒相互an灭时（根据爱因斯坦著名的方程式E = MC2）释放了许多能量。在瑞士，已经开始实验，以查看是否可以在癌症疗法中使用抗蛋白酶。该组（ACE协作）表明，抗蛋白酶比质子好四次。但是，在抗抗蛋白酶可以被认为是癌症放射疗法中的可行可能性之前，需要进行大量额外的科学工作。在2008年，申请人加入了ACE协作，并在CERN进行了一项实验，以研究抗植物对培养人类细胞的影响。他们表明，抗抗原子会对这些细胞中的DNA造成损害，并且细胞暴露于较高的抗蛋白酶，引起DNA损伤越多。此外，他们证明了来自辐照细胞的培养基会导致非辐照细胞中的DNA损伤反应。这种现象是所谓的旁观者效应，已在其他类型的辐射中得到充分证明，但以前尚未使用抗脂子照射显示。申请人现在寻求资金在2009年秋天返回CERN，以继续进行这些实验。今年，他们希望更多地了解抗蛋白辐射引起的旁观者效应，包括量化这些效果的大小。