Institute of Nuclear Physics Polish Academy of Sciences, PL-31342, Krakow, Poland.
FOCAS Research Institute, Technological University Dublin, Kevin Street, Dublin, 8, Ireland.
Sci Rep. 2019 Jun 18;9(1):8715. doi: 10.1038/s41598-019-45179-y.
Understanding the response of cancer cells to ionising radiation is a crucial step in modern radiotherapy. Raman microspectroscopy, together with Partial Least Squares Regression (PLSR) analysis has been shown to be a powerful tool for monitoring biochemical changes of irradiated cells on the subcellular level. However, to date, the majority of Raman studies have been performed using a single spectrum per cell, giving a limited view of the total biochemical response of the cell. In the current study, Raman mapping of the whole cell area was undertaken to ensure a more comprehensive understanding of the changes induced by X-ray radiation. On the basis of the collected Raman spectral maps, PLSR models were constructed to elucidate the time-dependent evolution of chemical changes induced in cells by irradiation, and the performance of PLSR models based on whole cell averages as compared to those based on average Raman spectra of cytoplasm and nuclear region. On the other hand, prediction of X-ray doses for individual cellular components showed that cytoplasmic and nuclear regions should be analysed separately. Finally, the advantage of the mapping technique over single point measurements was verified by a comparison of the corresponding PLSR models.
了解癌细胞对电离辐射的反应是现代放射治疗的关键步骤。拉曼微光谱分析与偏最小二乘回归（PLSR）分析已被证明是监测照射细胞亚细胞水平生化变化的有力工具。然而，迄今为止，大多数拉曼研究都是使用每个细胞的单个光谱进行的，这使得对细胞的总生化反应的了解有限。在当前的研究中，对整个细胞区域进行了拉曼映射，以确保更全面地了解 X 射线辐射引起的变化。基于收集的拉曼光谱图，构建了 PLSR 模型，以阐明照射诱导的细胞内化学变化的时变演化，以及基于整个细胞平均值的 PLSR 模型与基于细胞质和核区平均拉曼光谱的模型的性能比较。另一方面，对单个细胞成分的 X 射线剂量预测表明，细胞质和核区应分别进行分析。最后，通过比较相应的 PLSR 模型，验证了映射技术相对于单点测量的优势。
