Comprehensive Computational Screening and Analysis of Natural Compounds Reveals Promising Estrogen Receptor Alpha Inhibitors for Breast Cancer Therapy

Breast cancer remains a leading cause of death among women, with estrogen receptor alpha (ERα) overexpression playing a pivotal role in tumor growth and progression. This study aimed to identify novel ERα inhibitors from a library of 561 natural compounds using computational techniques, including virtual screening, molecular docking, and molecular dynamics simulations. Four promising candidates—Protopine, Sanguinarine, Pseudocoptisine, and Stylopine—were selected based on their high binding affinities and interactions with key ERα residues. Molecular dynamics simulations conducted over 500 nanoseconds revealed that Protopine and Sanguinarine exhibited more excellent stability with minimal fluctuations, suggesting strong and stable binding. In contrast, Pseudocoptisine and Stylopine showed higher flexibility, indicating less stable interactions. Binding free energy calculations further supported the potential of Protopine and Sanguinarine as ERα inhibitors, though their binding strength was slightly lower than that of the reference compound. These findings highlight Protopine and Sanguinarine as leading candidates for further investigation, and in vitro and in vivo studies are recommended to evaluate their therapeutic potential in breast cancer treatment.