TUNABLE X-RAY CANCER PHOTOTHERAPY

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。我们希望验证这样一种假设，即在肿瘤细胞内结合到底物上的各种重金属的K边缘及其以上的单色X射线照射在体外杀死肿瘤细胞的效果比传统的放射疗法更有效。该计划是SLAC速调管部门康普顿光源(CLS)项目的一部分，该项目旨在开发一种可调谐的、紧凑的准单能X射线源，用于癌症检测和治疗。虽然CLS正在开发中，但我们建议使用斯坦福同步辐射实验室(SSRL)的光束线来研究X射线光疗中的剂量增强。这项拟议的工作将使用SSRL光束线照射用高Z原子标记的已建立的细胞系。剂量增强将通过传统菌落计数和生物发光分析产生的剂量-反应曲线进行评估。辐射增敏剂的候选药物包括碘、Gd、铟、铂和金。样品将以高于这些元素K边的0-30keV的能量被照射。尽管SSRL光束线在这些能量下产生相对较低的通量，但细胞培养几何形状可以调整到较小的光束尺寸，并且可以长时间(几个小时)照射样品以达到更高的综合光子强度。在这些实验中允许更宽的带宽(高达1keV)，作为达到更高磁通的折衷方案。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. We wish to test the hypothesis that monochromatic x-ray radiation at and above the K-edge of various heavy metals bonded to substrates within neoplastic cells is more effective that conventional radiation therapy for killing neoplastic cells in vitro. This program is part of the Compton Light Source (CLS)project at the SLAC Klystron Department to develop a tunable, compact source of quasi-monoenergetic x-rays for use in cancer detection and treatment. While the CLS is under development, we propose to use a beamline at the Stanford Synchrotron Radiation Laboratory (SSRL) for studying dose enhancement in x-ray phototherapy. The proposed work will use an SSRL beamline to irradiate established cell lines labeled with high-Z atoms. Dose enhancement will be assessed through dose-response curves generated both by traditional colony counting and by bioluminescence assay. Candidates for radiosensitizing agents include Iodine, Gadolinium, Indium, Platinum, and Gold. Saples will be irradiated at energies 0-30 keV above the K-edges of these elements. Although SSRL beamlines produce relatively low fluxes at these energies, cell culture geometry can be adjusted to the small beam size, and samples may be irradiated for long times (hours) to reach higher integrated photon intensities. Broader bandwidths (up to 1 keV) are permitted in these experiments as a trade-off for reaching higher fluxes.