Monitoring Metabolic Alteration in Cancer Cells upon Radiation Therapy by Surface-Enhanced Raman Scattering (SERS)

Abstract

Surface-Enhanced Raman Spectroscopy (SERS) is a highly selective and sensitive method that allows the tracking and identification of metabolites at low concentrations in cellular models. In this work, radiation-induced metabolism changes were investigated by SERS using the MCF-7 breast cancer cell line. SERS analysis was carried out on a time course (1, 4, 8, 12-days post exposure) of supernatant samples from MCF-7 cell line cultures previously exposed to either 5 or 20 Gy of ionizing radiation. A significant radiation biomarker, hypoxanthine, was identified through principal component analysis. The amount of hypoxanthine released into the extracellular environment increased over time after exposure to ionizing radiation. A potential mechanism for hypoxanthine production was suggested. Additionally, Caspase-3 inhibitor (Peptide Z-DEVD-FMK) treatment was employed to improve MCF-7 cell viability following exposure to ionizing radiation and to establish the relationship between the release of hypoxanthine and cell apoptosis. This study provides a valuable preliminary assessment of the application of SERS to study metabolic changes that can be extended in the future to human-derived samples.