Tehran University of Medical Sciences Acta Biochimica Iranica 0001-5261 1 4 2023 12 20 176 182 Ali Karami Robati Department of Biochemistry, School of Medicine, Iran University of Medical Sciences, Tehran, Iran. Zahra Shahsavari Department of Clinical Biochemistry, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Mohammad Amin Vaezi Department of Biochemistry, School of Medicine, Iran University of Medical Sciences, Tehran, Iran. Banafsheh Safizadeh Department of Biochemistry, School of Medicine, Iran University of Medical Sciences, Tehran, Iran. Farzad Izak Shirian Department of Biochemistry, School of Medicine, Iran University of Medical Sciences, Tehran, Iran. Masoumeh Tavakoli-Yaraki Department of Biochemistry, School of Medicine, Iran University of Medical Sciences, Tehran, Iran. 2024 01 01 Objectives: The aim of this study is to evaluate the potential effect of caffeic acid (CAF) on the growth of breast cancer cells, in addition to determining the contributing role of caspases, mitochondria, and oxidative status. Methods: MCF-7 and MDA-MB-468 breast cancer cells were exposed to varying concentrations of CAF for different periods of time. The potential cytotoxic effect was measured using the MTT assay. The activities of caspase 3 and caspase 8, as well as the cellular level of reactive oxygen species (ROS) and the level of mitochondrial membrane potential (Δψm), were evaluated in different groups of cells. Results: The findings showed that CAF decreased the percentage of MCF-7 and MDAMB-468 cells in a manner that depended on the dose and duration of exposure. The death of breast cancer cells induced by CAF was associated with an increase in ROS level in both cell lines. The decrease in mitochondrial membrane potential (Δψm) following CAF treatment suggests that mitochondrial dysfunction may be involved in the death of breast cancer cells induced by CAF. Importantly, the activity of caspase 8 increased after treatment, indicating the potential involvement of the extrinsic apoptosis pathway in the inhibition of breast cancer cell growth by CAF. The dosage of 20μm of CAF following 48 hours of incubation appeared to have the most significant impact on breast cancer cells. Conclusion: The study highlights the potential pro-apoptotic effect of CAF in both estrogen-positive and estrogen-negative breast cancer cells. This, in conjunction with other evidence, may lead to new insights for more effective therapeutic approaches in breast cancer. https://abi.tums.ac.ir/index.php/abi/article/view/67 https://abi.tums.ac.ir/index.php/abi/article/download/67/32