1176 – Microrna dysregulation and endocrine disruptors in breast cancer: molecular implications for tumor progression

Abstract

Breast cancer is one of the most common malignancies among women worldwide and its development involves genetic,
hormonal and environmental factors. MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression
at the post-transcriptional level and play important roles in tumorigenesis. Altered miRNA expression has been associated with cell proliferation, apoptosis, invasion and metastasis in breast cancer. Endocrine disruptors with estrogenic
activity, such as Bisphenol A, may also influence tumor progression by modulating miRNA expression in breast cancer
cells. A literature-based analytical study was conducted to evaluate the role of miRNAs in breast cancer progression and
the potential modulation of these molecules by endocrine disruptors. Scientific studies investigating miRNA expression
in breast cancer and experimental studies evaluating the effects of endocrine disruptors on miRNA regulation in breast
carcinoma cells were analyzed. Several miRNAs show altered expression in breast tumors and are associated with tumor
behavior. Among them, miR-21 is frequently upregulated and has been linked to increased invasive capacity through
negative regulation of tumor suppressor genes such as TIMP3. Additionally, miR-204 has been implicated in tumor
aggressiveness and vasculogenic mimicry through regulation of targets including CREB5. Experimental evidence also
indicates that endocrine disruptors can alter the miRNA expression profiles in breast cancer cell lines, including MCF-7
cells. MicroRNAs play an important role in molecular mechanisms associated with breast cancer progression, therefore
understanding how endocrine disruptors influence miRNA regulation may contribute to identifying molecular biomarkers and potential therapeutic targets.
Ethics: Public data – Literature review.
Funding: CNPq nº 02/2025.