Advanced renal cell carcinoma and triple negative breast cancer (TNBC) are malignancies without effective therapeutics currently. Ursolic acid (UA) has been previously reported to have anti-cancer effects in multiple solid tumors. In order to develop more potent anti-cancer reagents, FZU-03,010 based on the chemical structure of UA were synthesized. The results demonstrated that, compared with UA, FZU-03,010 could suppress renal cancer cell 786-0 and TNBC cell HCC1806 cell viability more potently.  Furthermore, FZU-03,010 could induce G1 cell cycle arrest and cell apoptosis more efficiently than UA. FZU-03,010 could also inhibit signal transducer and activator of transcription 3 activation, induce the expression of cell cycle-dependent kinase inhibitors (p21 and p27) and promote cell apoptosis. In conclusion, our results suggest that the UA derivative FZU-03,010 is more potent in inhibiting cancer cell survival, and FZU-03,010 has the potential to be developed as a therapeutic for renal cell cancers and TNBCs.

The present study investigated the anticancer functions of ursolic acid (UA) and its novel derivatives, with a nitrogen-containing heterocyclic scaffold and the privileged fragment at the C-28 position on apoptosis induction, cell proliferation and cell cycle in human BC lines. UA was chemically modified in the present study to increase its antitumor activity and bioavailability. A novel UA derivative, FZU3010, was synthesized using a nitrogen-containing heterocyclic scaffold and a privileged fragment at the C-28 position. Sulforhodimine B assays were used to measure the effect of UA and different concentrations of FZU3010 on the viability of breast cancer (BC) SUM149PT and HCC1937 cells. FZU3010 significantly repressed the proliferation of the two cancer cell lines in a dose-dependent manner, with a half-maximal inhibitory concentration of 4–6 µM, and exhibited decreased cytotoxicity compared with vehicle-treated cell lines. The effect of FZU3010 on cell cycle distribution and cellular apoptosis was also investigated. The results of this investigation indicated that FZU3010 significantly increased the number of SUM149PT and breast cancer HCC1937 cells in the G0/G1 phase in a dose-dependent manner. Additionally, at a concentration of 5 µM, the capability of FZU3010 to induce BC apoptosis was significantly higher than the capability of UA. Thus, the results of the current study indicated that FZU3010 induced apoptosis in BC cells, together with induction of cell cycle arrest at the S and G0/G1 phase. FZU3010 may therefore be considered as a potential therapeutic agent for the treatment of BC.