Selective Cytotoxicity and Gene Expression Profiles in Response to Methanolic Extract of <i>Phyllanthus amarus</i> Extract against MCF-7 Breast Cancer Cells

Background Breast cancer, a malignant tumor, is the most common cancer type among women worldwide. Conventional chemotherapy treatments for breast cancer often cause adverse side effects in normal tissues and can lead to treatment failure. Plant-derived natural compounds offer an effective alternative with fewer side effects for cancer patients. Phyllanthus amarus is a medicinal plant widely distributed in China, India, and Brazil and reported to be used for the treatment of various types of cancer. Objectives This study was aimed to investigate the anticancer efficacy of methanolic extract of P. amarus against MCF-7 breast cancer cells. Materials and Methods We probed the anticancer activity in MCF-7 breast cancer cells by isolating the methanolic extract of P. amarus leaf extract (MEPA). The standard chemotherapy drug docetaxel is combined with MEPA to increase the drug efficacy. Moreover, the intracellular reactive oxygen species (ROS), alterations in mitochondrial membrane potential (MMP), nuclear condensation, and apoptotic activation were investigated in MCF-7 cells. Additionally, the customized PCR array comprising of cell cycle, apoptosis, mTOR, and JAK-STAT-related genes was studied during different MEPA treatments. Results In the MCF-7 breast cancer cells, the MEPA and docetaxel combination demonstrated strong cytotoxicity, with IC 50 values of 45 and 2.6 µg/mL, respectively. MEPA and docetaxel together exhibited enhanced alterations in MMP and increased generation of ROS in MCF-7 cells. Furthermore, the combination of docetaxel with MEPA induces nuclear condensation and apoptotic cell death. During MEPA treatment, the gene expression profiles in MCF-7 cells were accessed. The JAK-STAT, mTOR signaling pathway, apoptosis, and cell growth-related genes were strongly affected by the dose-dependent administration of MEPA. Conclusion This study suggests that MEPA could be a useful alternative treatment for breast cancer. When combined with traditional chemotherapy, MEPA might offer better results with fewer side effects. More in vivo studies are needed to confirm MEPA’s effectiveness in animal models.