An in vitro assessment of ionizing radiation impact on the efficacy of radiotherapy for breast cancer

Abstract

Objectives Ionizing radiation is still one of the most effective treatment options for various cancers. It is possible to reduce the side effects of this effective treatment method and increase the chance of success by elucidating the responses it creates at the molecular level in the cell. This study aims to investigate of the molecular effects of therapeutic ionizing radiation on breast cancer, which is the most prevalent cancer type. Methods MDA-MB-231 and MCF7 cell lines were irradiated with 4 and 8 Gy ionizing radiation and monitored for up to 7 days. RNA was collected at 48 and 96 h, when cellular molecular mechanisms became most evident, and quantitative expression levels of microRNAs (miR-208a, miR-124, miR-145), for which cancer-radiation associations have been determined from existing literature and databases, were evaluated. Results Exposure to ionizing radiation resulted in a dose-dependent reduction in cell viability in both MCF7 and MDA-MB-231 breast cancer cell lines. Furthermore, microRNA expression analysis revealed notable changes at all levels. The research demonstrates that miR-208a, miR-145, and miR-124 are crucial in the biological response to ionizing radiation. Conclusions Therapeutic ionizing radiation profoundly affects cell viability and microRNA expression in breast cancer cell lines, showing dose and time-dependent effects. The observed microRNA expression patterns suggest potential biomarkers for radiation response and therapeutic targets to improve radiotherapy efficacy. Further in vivo validation and exploration of these microRNAs’ roles in modulating cellular response to ionizing radiation are needed.