Total flavonoids of Litchi seed attenuate stem cell-like properties in breast cancer by regulating Notch3 signaling pathway

• Published in: Journal of ethnopharmacology 2023-04, Vol.305, p.116133-116133, Article 116133
• Main Authors: Liao, Yunnuo, Luo, Zhuo, Liu, Ying, Xue, Wei, He, Songhua, Chen, Xin, Ren, Hong, Yang, Xin, Zhu, Dan, Su, Zhiheng, Huang, Qiuju, Guo, Hongwei
• Format: Article
• Language: English
• Subjects: Animals; Breast cancer stem cells; Breast Neoplasms - pathology; Cell Line, Tumor; Cell Proliferation; Female; Flavonoids - metabolism; Flavonoids - pharmacology; Flavonoids - therapeutic use; Humans; Litchi; Mice; Neoplastic Stem Cells; Notch3; Receptor, Notch3 - metabolism; Seeds; Signal Transduction; Total flavonoids of Litchi seed
• ISSN: 0378-8741; 1872-7573
• DOI: 10.1016/j.jep.2023.116133

Breast cancer has been the most commonly-diagnosed cancer worldwide, and the treatment and prognosis of which are often limited by breast cancer stem cells (BCSCs). Litchi seeds have shown good anti-cancer activity in various cancers including prostate cancer, lung cancer and breast cancer. However, the activity and underlying mechanism of Litchi seeds against BCSCs remain unknown. To investigate the activity and mechanism of total flavonoids of litchi seed (TFLS) against BCSCs in vitro and in vivo. Two orthotopic xenograft mouse models were established using HCC1806 cells pretreated or untreated with TFLS to determine whether TFLS could target BCSCs in vivo. Mammosphere formation and flow cytometry assays were employed to evaluate the effect of TFLS on BCSCs in vitro. The underlying mechanism was investigated using RT-qPCR, Western blot, immunohistochemistry and immunofluorescence experiments. TFLS could significantly inhibit the viability of HCC1806, MCF-7 and HCC1937 cells in vitro and suppress the growth of HCC1806 cells in vivo. TFLS attenuated stem cell-like properties of breast cancer through reducing the percentage of CD44+CD24-/low cells, inhibiting the mammospheres formation and down-regulating the mRNA and protein levels of cancer stem cells related markers (Oct4, Nanog, Sox2) in MCF-7 and HCC1806 cells. Meanwhile, TFLS suppressed the tumor-initiating ability of BCSCs via reducing the percentage of CD44+CD24-/low cells in tumor and lowering tumor incidence rate in orthotopic xenograft mice. In addition, TFLS treatments restricted the expression and nuclear translocation of Notch3, subsequently down-regulated Hes1 and Runx2 expressions. TFLS could suppress the growth of breast cancer and eliminate breast cancer stem cells by inhibiting the Notch3 signaling pathway. [Display omitted] •TFLS inhibit breast cancer in vitro and in vivo.•TFLS attenuate breast cancer stem cells in vitro and restrict their tumorigenic ability in vivo.•TFLS decrease the expression and nuclear translocation of Notch3, subsequently down-regulate Hes1 and Runx2 expressions.