ORIGINAL ABSTRACT

Breast cancer is the most common neoplasm in women worldwide, with both genetic and environmental factors playing a role in its development. Glyphosate, the active ingredient in widely used agricultural herbicides, is recognized as a potential carcinogen and endocrine disruptor, making it a candidate for inducing epigenetic modifications linked to breast cancer. This study investigates the effects of the glyphosate-based herbicide Roundup® on non-tumorigenic (MCF10A) and tumorigenic (MCF7 and MDA-MB-231) breast cell lines, focusing on the expression of key breast cancer-related genes. Additionally, the study examines the association with epigenetic modifications and the use of epidrugs to reverse potential alterations, aiming to understand the risks and mechanisms of herbicide action. Results indicate that Roundup® affects cells through a non-estrogenic mechanism, impacting both hormone-dependent and -independent cells with varying toxic and proliferative effects depending on dose and exposure time. Moreover, it altered the expression of breast cancer-related genes such as BRCA1 and BRCA2 at low doses. The use of epigenetic modulators was able to reverse some Roundup®-induced changes, suggesting the herbicide's role in epigenetic modifications. Overall, these findings highlight the importance of understanding glyphosate-based herbicide mechanisms in humans, which could enable personalized prevention strategies to mitigate breast cancer risks.