Interval-Principal Component Analysis of Raman spectra of single cells exposed to X-ray radiation

A Micro-Raman spectroscopy investigation has been performed on human mammary epithelial cells after irradiation by different X-ray doses. The analysis by interval-Principal Component Analysis (iPCA) has allowed us to outline the subtle differences in the Raman spectra induced by irradiation. In particular, this experimental approach has enabled to delineate radiation-induced changes in structure, protein, nucleic acid, lipid, and carbohydrate content. This has further confirmed that micro-Raman spectroscopy coupled to properly chosen data analysis methods is a very sensitive technique to detect molecular changes even in single human cells following exposure to ionising radiation. This would help developing innovative approaches to monitor radiation treatment effects so as to reduce the overall radiation dose and minimize damage to the surrounding healthy cells, both aspects being of great importance in the field of radiation therapy.