Cytotoxic Effect of α-Mangostin through Suppression of the Wnt/β-Catenin Pathway in Triple-Negative Breast Cancer Stem Cells

Triple-negative breast cancer stem cells (TNBCSCs) play a critical role in the high aggressiveness, metastatic potential, and therapeutic resistance of triple-negative breast cancer (TNBC). Consequently, targeting TNBCSCs represents a promising strategy to improve clinical outcomes in TNBC patients. α-Mangostin, a natural xanthone compound isolated from the tropical fruit Garcinia mangostana (mangosteen), has attracted attention for its potential anticancer properties. In this study, we investigated the inhibitory effects of α-mangostin on the growth of TNBCSCs derived from MDA-MB-231 and HCC1937 cell lines. Our results demonstrated that α-mangostin significantly inhibited both the proliferation and tumorsphere-forming capacity of TNBCSCs. Importantly, this antiproliferative effect was closely associated with the induction of apoptosis. Further mechanistic analysis revealed that α-mangostin suppressed the Wnt/β-Catenin signaling pathway and reduced the expression of key stemness-related markers. Collectively, these findings suggest that α-mangostin may serve as a promising natural therapeutic agent for the prevention and treatment of TNBC by targeting its cancer stem cell population.