In Vitro Cytotoxic Study of Euphorbia grantii Oliv. Aerial Parts against MCF-7 and MCF-7(ADR) Breast Cancer Cell Lines: A Bioactivity-Guided Isolation

[Image: see text] The development of highly efficient and low-toxicity anticancer drugs is one of the most critical problems in the medical field. Euphorbia grantii is commonly reported as an antiviral plant; a dilute solution of its latex is used for intestinal worms and to promote blood clotting and tissue healing. Our study evaluated the antiproliferative activity of the total extract, its respective fractions, and the isolated compounds from E. grantii aerial parts. A phytochemical study was done by several chromatographic methods, and the cytotoxic activity was assessed using the sulforhodamine B assay. The dichloromethane fraction (DCMF) exhibited promising cytotoxic activity against breast cancer cell lines (MCF-7 and MCF-7(ADR)), with an IC(50) of 10.31 and 10.41 μg/mL, respectively. Chromatographic purification of the active fraction revealed the isolation of eight compounds. Among the isolated compounds, euphylbenzoate (EB) exhibited a promising effect with an IC(50) of 6.07 and 6.54 μM against MCF-7 and MCF-7(ADR), respectively, while other compounds showed no activity. Euphol, cycloartenyl acetate, cycloartenol, and epifriedelinyl acetate showed moderate activity (33.27–40.44 μM). Euphylbenzoate has smartly tackled both apoptosis and autophagy programmed cell death mechanisms. These results demonstrated that E. grantii aerial parts yield active compounds with significant antiproliferative potential.