Recent studies have reported several beneficial effects of natural compounds on cancerous cells, highlighting their use for future treatments. These preliminary findings have encouraged experiments with natural substances, such as plant extracts, to examine both cytotoxic and mitogenic effects and find alternative treatments for diseases such as breast cancer. This study examines the effects of microwave-assisted and ethanol maceration of marjoram (Origanum majorana) on MCF-7 breast cancer cell lines and normal breast tissue cell lines used as controls. Marjoram extracts displayed a cytotoxic effect on the MCF-7 cell lines and a mitogenic effect on the control cell lines at the MTS test. The metabolic profiles of MCF-7 and control cell lines were also assessed using the Biolog Phenotype Mammalian Metabolic (PM-M) platform and revealed statistically significant differences in the utilization of energy sources, metabolic activity in the presence of certain ionic species, and responses to metabolic effectors, such as stimulant/catabolic compounds and steroid hormones. Exposure to marjoram extracts exerted positive effects on the MCF-7 cells on the abnormal utilization of energy sources and the responses to metabolic effectors, while no major effects were detected on control cells. These effects were compared to the metabolic impact of the chemotherapeutic agent doxorubicin, which showed profound cytotoxic effects on both cancerous and normal breast cells. In conclusion, our in vitro evidence indicates that marjoram extracts are a promising alternative to chemotherapy in breast cancer since they can successfully eliminate cancerous cells by affecting their metabolic capacity to proliferate without inducing noticeable adverse effects on normal breast tissue.
