Isoliquiritigenin-infused electrospun nanofiber inhibits breast cancer proliferation and invasion through downregulation of PI3K/Akt/mTOR and MMP2/9 pathways

Mastectomy followed by chemotherapy and radiotherapy is the current treatment regimen for breast cancer (BC). However, these approaches have systemic side effects and often lead to ineffective treatment outcomes. Therefore, a novel controlled release system is required to prevent tumor recurrence. Isoliquiritigenin (ISL), a dietary flavonoid, was shown to be effective against BC in our laboratory. However, its hydrophobicity and low bioavailability limit its anti-BC efficacy. Thus, the present study was designed to fabricate electrospun ISL-nanofiber scaffolds (ISL-NF) that can inhibit breast cancer growth and migratory capacity of BC cells in vitro and in vivo. The ISL-NF was prepared using an advanced coaxial electrospinning-cryocutting method, and characterized. Various assays, including cell viability, transwell, would healing, western blotting, and staining, were employed to explore the underlying mechanisms. In vitro studies showed that ISL-NF treatment for 24 h significantly inhibited cell proliferation, and migration and improved apoptosis in various BC cell lines. ISL-NF also decreased the protein expression of PI3K, Akt, mTOR, matrix metalloproteinase (MMP)-2, and MMP-9, thereby inhibiting BC cell invasion. Consistent with the in vitro study, ISL-NF treatment decreased tumor size and weight and inhibited tumor migration in 4T1 tumor-bearing mice. Based on the study, we suggest that ISL-NF may be useful in the treatment of BC.