Objective: To investigate the effects of Astragalus injection (AI) on basal-like breast cancer cell line MDA-MB-468 and murine bone marrow stromal stem cells (mMSCs).
Methods: MDA-MB-468 cells and primary cultured mMSCs were treated by different concentrations of AI, and with untreated MDA-MB-468 cells as blank control. The morphology of cells was observed by phase-contrast inverted microscope and transmission electron microscopy. Cytotoxic effects of AI on MDA-MB-468 cells and mMSCs were evaluated by cell counting kit-8 (CCK-8) assay. Cell cycle and apoptosis of MDA-MB-468 cells induced by AI were measured by flow cytometry. Lactate dehydrogenase (LDH) activity in supernatants was measured by enzymatic colorimetric method. The expressions of epidermal growth factor receptor (EGFR) and p53 protein in MDA-MB-468 cells were evaluated by streptavidin-biotin-peroxidase complex method.
Results: A time-dependent cytotoxic effect of 1 g/ml AI was observed in MDA-MB-468 cells. 1 g/ml AI also had cytotoxic effect on mMSCs, but its effect was not better than cisplatin. 0.1 g/ml AI could promote the proliferation of mMSCs. Different concentrations of AI could all induce the apoptosis of MDA-MB-468 cells. There was no significant difference in LDH activity in the supernatants between blank control group and AI-treated and cisplatin-treated groups. AI could down-regulate the expressions of EGFR and p53 protein.
Conclusion: The effects of AI on MDA-MB-468 cells and mMSCs are related to the concentration of AI, and its mechanism of inhibiting the proliferation of MDA-MB-468 cells may be due to down-regulation of the expressions of EGFR and p53 protein.