Al-Madhagy, Somaia. AGad, Sameh SMostafa, Eman SAngelonie, SimoneSaad, Muhammed ASabry, Omar MCaprioli, GiovanniEl-Hawary, Seham S2022-10-152022-10-152022-10https://doi.org/10.1080/14786419.2022.2130306http://repository.msa.edu.eg/xmlui/handle/123456789/5223Breast cancer is the most devastating disease for women. There is a great demand for new sources to treat this disease. Medicinal plants are an indispensable source of bioactive compounds with wide range of pharmacological activities. In-vitro cytotoxic activity of Otostegia fruticosa methanolic extract against human breast cancer was studied using MCF-7 cell line. The extract showed mildly potent activity (IC50 ¼ 51 ± 9.836 mg/mL) in comparison to the standard anticancer doxorubicin (IC50 ¼ 7.467 ± 1.05 mg/mL). Potential compounds responsible for activity have been identified using Molecular Operating Environment (MOE) module on the major compounds detected by HPLC-MS/MS technique against estrogen alpha receptor (ERaþ: PDB ID 2JF9). 3,5-di-O-dicaffeoyl- quinic acid, hyperoside and rutin showed similar binding and antagonistic interaction with the estrogen alpha receptor as tam- oxifen in several poses. The retrieved results confirm that we can add this plant to a powerful arsenal that combats this insidious disease.en-USMCF-7Otostegia fruticosaHPLC-MS/MSphenolicsestrogen alpha receptorArticle