Quercetin-Mediated Modulation of Tumor Suppressor miR-15a, miR-34a, and p53 Signaling in MCF-7 Breast Cancer Cells

Breast cancer remains one of the most prevalent types of cancer among women globally, contributing significantly to cancer-related mortality. Despite advancements in treatment, many cases continue to exhibit resistance to chemotherapy, radiotherapy, and hormonal therapies, often resulting in drug resistance, high recurrence rates, and severe side effects. Consequently, the role of the natural food components in cancer prevention and treatment is gaining increasing attention in modern medicine. This study focuses on quercetin, a phytochemical compound, and its effects on the breast cancer cell line MCF-7. Specifically, the study has investigated changes in the expression of miR-15a and miR-34a—microRNAs (miRNAs) known to regulate gene expression at the post-transcriptional level—and the P53 gene, which is critically involved in apoptosis. The analysis was performed using quantitative polymerase chain reaction (qPCR) and Western blot techniques. The results demonstrated that quercetin treatment at concentrations of 40 µM and 80 µM led to a 1.34-fold and 2.73-fold increase in P53 gene expression, respectively. Additionally, the tumor suppressor miRNA miR-15a showed expression changes of 1.48-fold and 1.69-fold at the same quercetin concentrations. Similarly, miR-34a expression levels increased by 1.23-fold and 1.39-fold at 40 µM and 80 µM, respectively. These findings suggest that dietary phytochemicals, such as quercetin, may have therapeutic potential by modulating miRNA expression and targeting the p53 pathway. In conclusion, quercetin emerges as a promising natural therapeutic agent for breast cancer, warranting further in vivo studies and clinical trials to confirm its efficacy and explore its potential as a part of combination therapies.