• Evaluating Cytotoxic Effects of Doxorubicin on MDA-MB-231 Triple-Negative Breast Cancer Cells
  • Nika Gholamrezaei,1,* Shahrokh Safarian,2 Seyed Jalal Zargar,3
    1. Department of Cell and Molecular Biology, School of Biology, College of Science, University of Tehran, Tehran, Iran
    2. Department of Cell and Molecular Biology, School of Biology, College of Science, University of Tehran, Tehran, Iran
    3. Department of Cell and Molecular Biology, School of Biology, College of Science, University of Tehran, Tehran, Iran


  • Introduction: Breast cancer is one of the most prevalent malignancies among women and remains a leading cause of cancer-related mortality worldwide. Triple-negative breast cancer (TNBC) is a highly aggressive subtype characterized by the absence of estrogen receptors, progesterone receptors, and HER2 expression, making it the most challenging subtype to treat due to the lack of targeted therapies. The MDA-MB-231 cell line is widely used as an in vitro model for TNBC, given its molecular and metastatic properties. Doxorubicin, an anthracycline chemotherapeutic drug, is one of the standard chemotherapies used for TNBC treatment because of its ability to intercalate DNA and inhibit topoisomerase II, leading to cell death induction. However, its clinical application is limited by drug resistance and dose-dependent toxicity.
  • Methods: To assess the cytotoxic effect of doxorubicin on TNBC cells, MDA-MB-231 cells were cultured and treated with increasing concentrations of doxorubicin for 48 hours. Cell viability was then evaluated using the MTT assay, and the half-maximal inhibitory concentration (IC₅₀) was calculated.
  • Results: Treatment with doxorubicin significantly reduced the viability of MDA-MB-231 cells in a dose-dependent manner. The IC₅₀ value for doxorubicin after 48 hours of treatment was determined to be 1.18 μM.
  • Conclusion: Our findings confirm the sensitivity of MDA-MB-231 cells to doxorubicin and provide a baseline for future studies investigating drug resistance mechanisms or potential combination therapies in TNBC.
  • Keywords: Triple-negative breast cancer, MDA-MB-231, Doxorubicin, MTT assay, IC₅₀