Abstract:
Background: Breast cancer is the most commonly diagnosed cancer in women and one of the main causes of death within the female population. Radiotherapy is one of the main treatments, but its efficiency is limited by the radiosensitivity of both, the patient and the tumor. After irradiation, different types of DNA damage are induced, with the DNA double-strand breaks (DSB) being the most lethal. Studies have shown that the capacity of the cell to repair the radio-induced DSB is correlated with clinical and cellular radiosensitivity. Recently, a study has shown that Ro 90-7501, a drug that inhibits the development of amyloid β42 fibrils linked to Alzheimer’s disease, has significant radiosensitizing effects on cervical cancer cell lines by inhibiting the efficiency of the DNA DSB repair.
Aim: The purpose of this study is to assess the radio-sensitizing potential of Ro 90-7501 on breast cancer and normal skin fibroblast cell lines.
Materials and Methods: Two breast cancer cell lines, MDA and MCF7, and one normal skin fibroblast cell line, GM03652, were used in this study. The MTT and Trypan Blue assays have been employed to measure cell viability, proliferation, and cytotoxicity. The anti- pATM and anti-γH2AX Immunofluorescence assay was performed to measure the ability of cells to repair the DNA DSBs.
Results: Ro 90-7501 significantly decreased breast cancer cells’ viability and proliferation; however, it showed no effect on normal tissues. When combined with radiation, Ro 90-7501 enhanced the radio-sensitivity of breast cancer cells by inhibiting DSB repair, with limited effect on normal tissues.
Conclusion: This study revealed that the drug Ro 90-7501 is a promising radiosensitizer for breast cancer cell lines.
