Abstract
Therapy of breast cancer (BC) overexpressing the pro-survival protein Bcl-2 remains a major clinical challenge. The discovery of natural anticancer drugs with potential as Bcl-2 inhibitors has generated increasing interest. The medicinal plant Teucrium polium L. (TPL) exhibits pharmacological properties, including anticancer activities. This study aimed to assess the antiproliferative and pro-apoptotic effects of TPL extracts on BC cells and to predict the potential of TPL extract-derived metabolites as Bcl-2 inhibitors. Plant extraction was performed using several solvents, and cell viability was determined. The expression of proteins and genes related to apoptosis was evaluated using Western blot, the Proteome Profiler™ Human Apoptosis Array Kit, and qPCR, respectively. Caspase-3/7 and mitochondrial permeability transition pore opening (mPTPO) activities were visualized. GC/MS analysis, molecular docking, and in silico modeling were used for metabolite identification, prediction of their molecular interactions with Bcl-2, and their pharmacokinetic profiles. Among extracts, TPL methanolic extract (TPLME) dose-dependently reduced hormone-dependent and triple-negative BC cell viability, while sparing normal mammary epithelial cells. TPLME induced apoptosis by increasing caspase-3/7 activity, activating distinct apoptotic pathways, and modulating BAX, TP53, and BCL-2 gene expression. Differential BCL-2 expression levels in TPLME-treated BC cells were confirmed by variations in mPTPO activity. After TPLME-derived metabolite identification, molecular docking revealed interactions between key metabolites and the active site of Bcl-2. Predictive analysis revealed the safe pharmacokinetic profiles of TPLME-derived metabolites. These findings highlight the promising potential of TPLME-derived metabolites for the development of novel Bcl-2 inhibitors for BC cells, requiring further chemical development and preclinical investigations using in vivo BC models.