Therapeutic implications of Epirubicin-induced miRNA-22 and miRNA-331 upregulation on cell viability and metastatic potential in triple-negative breast cancer

Background

Triple-negative breast cancer (TNBC) represents a significant clinical challenge, with chemoresistance and metastasis remaining major barriers to successful treatment outcomes. This in vitro study aimed to elucidate the molecular mechanisms underlying epirubicin's effects on TNBC through careful examination of miRNA modulation.

Methods

Epirubicin's effects on TNBC cells were assessed through MTT assay to determine IC50. miRNA-22 and miRNA-331 expression levels were analyzed using Real-Time PCR. Morphological changes were observed microscopically.

Results and discussion

Epirubicin treatment (0–6 μg/mL) demonstrated significant dose-dependent cytotoxicity against MDA-MB-231 cells, with IC50 values decreasing from 2.49 μg/mL at 24 h to 0.145 μg/mL at 48 h. Morphological analysis revealed marked cellular alterations including increased size and elongated phenotype post-treatment. A marked upregulation of miRNA-22 expression was observed post-treatment, implicating its role in metastasis regulation. In contrast, miRNA-331 expression changes were negligible. The observed miRNA-22 upregulation aligns with its reported tumor-suppressive functions in TNBC, suggesting its potential role in mediating epirubicin's therapeutic effects.

Conclusion

miRNA-22 is a promising candidate for combination therapies in TNBC. Study limitations include single-cell line use and a narrow focus on two miRNAs. Future research should expand miRNA profiling and evaluate therapeutic potential across diverse TNBC models. Challenges like resistance remain critical to address.