Application of a vertical charged-particle irradiation platform in glioblastoma multiforme cancer stem cell research

Cancer stem cells (CSCs) are characterized by two critical properties similar to those of normal stem cells, namely, self-renewal and differentiation. Therefore, they play a crucial role in tumor development and tumor treatment responses. Glioblastoma multiforme (GBM) is the most aggressive form of brain tumor in humans, with extremely poor survival rates. GBM CSCs are believed to contribute to cancer initiation, invasion, metastasis, and recurrence, and they can also lead to poor conventional radiation therapy and chemotherapy outcomes. Efficiently eliminating CSCs is thus crucial to developing GBM treatment strategies. This study aimed to demonstrate the application of a vertical charged-particle irradiation platform in CSC research. The cell irradiation results indicated that GBM CSCs were more radio-resistant and had a higher survival rate than ordinary GBM tumor cells. Expression of DNA double-strand break (DSB) repair modulation protein in GBM CSCs was also higher than in ordinary GBM tumor cells, suggesting that the radioresistance of GBM CSCs might be relative to efficient DNA DSB repair. Targeting the DNA DSB repair mechanism could thus be a potential strategy for enhancing GBM tumor control. All of the results demonstrated that the vertical charged-particle irradiation platform provides a suitable environment for CSC charged-particle irradiation research.