Conclusion
The present study demonstrated that silibinin may have exerted its anti-tumor effects in BC by targeting the BC stem cells, reducing the tumorgenicity and metastasis. Therefore, silibinin may be a potential adjuvant for treatment of BC.
Methods
The effect of silibinin on viability and proliferation of MCF-7, MDA-MB-231 mammospheres, and MDA-MB-468 cell aggregation was determined after 72-120 hours of treatment. Colony and sphere formation ability, and the expression of stemness, differentiation, and epithelial-mesenchymal-transition (EMT)-associated genes were assessed by reverse transcription-quantitative polymerase chain reaction (qRT-PCR) in mammospheres treated with an IC50 dose of silibinin. Additionally, the antitumor capacity of silibinin was assessed in vivo, in mice.
Results
The results of the present study showed that silibinin decreased the viability of all mammospheres derived from MCF-7, MDA-MB-231, and MDA-MB-468 cell aggregation in a dose-dependent manner. Colony and sphere-forming ability, as well as the expression of genes associated with EMT were reduced in mammospheres treated with silibinin. Additionally, the expression of genes associated with stemness and metastasis was also decreased and the expression of genes associated with differentiation were increased. Intra-tumoral injection of 2 mg/kg silibinin decreased tumor volumes in mice by 2.8 fold.