Ergostatrien-3β-ol suppresses breast cancer anoikis resistance and metastasis by targeting the miR-93-5p/leupaxin axis.

Breast cancer is the malignancy most frequently diagnosed among women and ranks as a top cause of cancer-related deaths globally, with distant metastasis being the main factor behind these fatalities. Current systemic and locoregional therapies are hampered by severe side effects and limited survival benefits, highlighting the urgent need for novel therapeutic strategies. Ergostatrien-3β-ol (EK100), a natural sterol isolated from Antrodia camphorata, is known for its anti-inflammatory properties; however, its role in breast cancer metastasis remains unexplored. Here, we demonstrate that EK100 potently inhibits migration and anoikis resistance in breast cancer cells. RNA sequencing revealed significant downregulation of focal adhesion pathway genes, with leupaxin identified as a key target. Clinical correlation analyses showed that elevated leupaxin expression is linked with advanced disease, metastasis, and poor overall survival in breast cancer patients. Mechanistically, EK100 induces miR-93-5p upregulation, which suppresses leupaxin expression, thereby attenuating leupaxin-dependent migration and anoikis resistance. Molecular docking further predicts direct binding of EK100 to leupaxin, supporting a potential direct inhibitory mechanism. Importantly, EK100 suppresses leupaxin expression and significantly reduces breast cancer metastasis in vivo. Collectively, these findings position EK100 as a promising therapeutic candidate for metastatic breast cancer.