Abstract
3α-Hydroxysteroid dehydrogenase type 3 (3α-HSD3) is a key steroid-metabolizing enzyme involved in the regulation of intratumoral androgen and estrogen levels, predominantly in estrogen receptor-positive (ER⁺) MCF-7 breast cancer cells. Its dysregulation influences proliferation, survival, and resistance to hormone-based therapy. The main goal of this study is to identify potential natural inhibitors of 3α-HSD3 from Terminalia arjuna phytoconstituents to modulate MCF-7 breast cancer cell proliferation. A panel of nine phytochemicals were evaluated through molecular docking, ADMET profiling, HOMO-LUMO energy gap analysis, and prediction of activity spectra for substances (PASS) to assess their drug-likeness and preliminary activity. Subsequently, molecular dynamics (MD) simulations were performed on top candidates to explore the structural stability and interaction dynamics of protein-ligand complexes. The selected compounds exhibited favorable docking scores against 3α-HSD3, with Luteolin(CMP1), Leucocyanidin(CMP2), Gallic Acid(CMP3), and Ellagic Acid(CPM4) forming stable hydrogen bonds with key active site residues. This study showed that the top four compounds may serve as potential 3α-HSD3 inhibitors of breast cancer, warranting further in vivo validation.