SZC010 suppresses breast cancer development by regulating the PI3K/Akt/NF-κB signaling pathway

Breast cancer has become one of the leading causes of cancer deaths and is the most frequently diagnosed cancer among females worldwide. Despite advances in breast cancer therapy, metastatic disease in most patients will eventually progress due to the development of de novo or secondary resistance. Thus, it is extremely important to seek novel drugs with high effectiveness and low toxicity for systematic therapy.

We applied a 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in this study to analyze and evaluate the cytotoxic activity of oleanolic acid (OA) and its derivatives in three types of breast cancer cell lines (MDA-MB-231, MCF-7, and MDA-MB-453). A flow cytometry assay was performed to access the mechanisms of apoptosis and cell cycle analysis in SZC010 in MDA-MB-453 cells. Apoptosis- and cyclin-related proteins were evaluated by western blot. The key proteins of the NF-κB and PI3K-Akt-mTOR signaling pathway were also evaluated by western blot.

Our results revealed that all OA derivatives were more effective than OA in three types of breast cancer cell lines (MCF-7, MDA-MB-231, and MDA-MB-453). Among these seven OA derivatives, SZC010 exhibited the most potent cytotoxicity in MDA-MB-453 cells. Additionally, we observed that SZC010 treatment induced dose-and time-dependent growth inhibition in MDA-MB-453 cells. Furthermore, we demonstrated that SZC010 induced growth arrest in the G2/M phase and apoptosis by inhibition of NF-κB activation via the PI3K/Akt/mTOR signaling pathway.

Our data indicate that the novel OA derivative, SZC010, has great potential in breast cancer therapy.