Matrine exerts anti‑breast cancer activity by mediating apoptosis and protective autophagy via the AKT/mTOR pathway in MCF‑7 cells

Abstract

Matrine, a major alkaloid isolated from the traditional Chinese herb Sophora flavescens, has been used clinically to treat breast cancer in China. However, the effects of matrine on apoptosis and autophagy in breast cancer cells remain unclear. In the present study, the anti‑breast cancer capacity of matrine was evaluated and its role in regulating apoptosis and autophagy in vitro was investigated. Matrine significantly inhibited the growth of MCF‑7 cells. In addition, Hoechst 33342 staining and Annexin V/propidium iodide staining demonstrated that incubation with matrine induced apoptosis in MCF‑7 cells. Furthermore, matrine induced autophagy in MCF‑7 cells, manifesting as an accumulation of light chain 3 II and downregulation of p62. Additionally, matrine suppressed AKT and mammalian target of rapamycin (mTOR) phosphorylation, indicating that the AKT/mTOR pathway is involved in matrine‑induced apoptosis and autophagy. Overall, the results of the present study indicated that matrine possesses anti‑breast cancer activity by providing protective autophagy via inhibition of the AKT/mTOR pathway. These findings indicated that matrine may be a promising candidate for drug development targeting breast cancer.

Figure 1.

Chemical structure of matrine. (A) 2-D Structure of matrine and (B) 3-D conformer of matrine. Chemical formula: C₁₅H₂₄N₂O, molecular weight: 248.37 g/mol, from PubChem https://pubchem.ncbi.nlm.nih.gov/compound/91466.

Figure 2.

Effects of matrine on the cell viability of human breast cancer MCF-7 cells. MCF-7 cells were treated with 2, 4, 8 and 10 mM matrine for 24, 48 and 72 h. Subsequently, cell viability was measured using a CCK-8 assay. The data are expressed as the means ± standard deviation from three independent experiments. *P<0.05 vs. the control group; **P<0.01 vs. the control group; ***P<0.001 vs. the control group; ^#P<0.05 vs. 2 mM groups; ^##P<0.01 vs. 2 mM groups; ^###P<0.001 vs. 2 mM groups.

Figure 3.

Effects of matrine on morphologic changes of human breast cancer MCF-7 cells. MCF-7 cells were treated with 2, 4 and 8 mM matrine for 24 h. The morphological features were observed using microscopy at ×200 magnification. MCF-7 cells incubated with matrine demonstrated shrinkage, membrane blebbing, ballooning and partial detachment.

Figure 4.

Effects of matrine on human breast cancer MCF-7 cell apoptosis. MCF-7 cells were treated with 2, 4 and 8 mM matrine for 24 h. (A) Apoptotic condensed nuclear changes were quantified using Hoechst 33342 staining and observed using fluorescence microscopy at ×200 magnification. (B) Apoptosis was determined by Annexin V-FITC/PI staining and flow cytometry. Statistical analysis was performed using one-way ANOVA followed by Tukey's multiple comparison test; ***P<0.001 vs. the control group; ^#P< 0.05 and ^###P< 0.001 vs. the 2 mM matrine group. UL: Upper left, UR: Upper right, LL: Lower left, LR: Lower right.

Figure 5.

Effects of matrine in inducing autophagy in breast cancer MCF-7 cells. MCF-7 cells were treated with and without matrine for 24 h. The levels of the autophagy-related protein p62 and LC3-II were confirmed using western blotting, with β-actin used as loading control. LC3, light chain 3. **P<0.01 vs. the control group.

Figure 6.

Effects of matrine on the activation of the AKT/mTOR pathway. MCF-7 cells were treated with and without matrine for 24 h. Cell extracts were analyzed by western blotting with antibodies specific for p-AKT and p-mTOR. Quantification of protein expression levels of p-AKT and p-mTOR to β-actin. **P<0.01 vs. the control group. p-, phosphorylated; mTOR, mammalian target of rapamycin.