ABSTRACT
Breast cancer stem cells (BCSCs) are responsible for breast cancer metastasis, recurrence and treatment resistance, all of which make BCSCs potential drivers of breast cancer aggression. Ginsenoside Rg3, a traditional Chinese herbal medicine, was reported to have multiple antitumor functions. Here, we revealed a novel effect of Rg3 on BCSCs. Rg3 inhibits breast cancer cell viability in a dose- and time-dependent manner. Importantly, Rg3 suppressed mammosphere formation, reduced the expression of stemness-related transcription factors, including c-Myc, Oct4, Sox2 and Lin28, and diminished ALDH(+) populations. Moreover, tumor-bearing mice treated with Rg3 exhibited robust delay of tumor growth and a decrease in tumor-initiating frequency. In addition, we found that Rg3 suppressed breast cancer stem-like properties mainly through inhibiting MYC expression. Mechanistically, Rg3 accelerated the degradation of MYC mRNA by enhancing the expression of the let-7 family, which was demonstrated to bind to the MYC 3' untranslated region (UTR). In conclusion, our findings reveal the remarkable suppressive effect of Rg3 on BCSCs, suggesting that Rg3 is a promising therapeutic treatment for breast cancer.
ABSTRACT
Ginsenoside Rg3 (GS-Rg3), a sterol molecule isolated from ginseng, has demonstrated various immunological properties, including inhibition of cancer cell proliferation and metastasis, reversal of drug resistance and enhancement of chemotherapy sensitivity. The recent surge in attention towards GS-Rg3 can be attributed to its potential as an antitumor angiogenesis agent and as a therapeutic candidate for immunotherapy. The development of GS-Rg3 as an agent for these purposes has accelerated research on its mechanisms of action. The present review summarizes recent studies investigating the antitumor activity of GS-Rg3 and its underlying mechanisms, as well as providing essential information for future studies on GS-Rg3.
