Novel antitumor compound optimized from natural saponin Albiziabioside A induced caspase-dependent apoptosis and ferroptosis as a p53 activator through the mitochondrial pathway.

It is highly desirable to activation p53 function with small-molecule compounds for colon cancer therapy. Triterpene saponin has been characterized with the favorable selectivity and safety profiles. However, the application of triterpene saponin as cancer chemotherapy drugs was hampered primarily by moderate anticancer potency and the lack the mechanism of action. In this study, we synthesized a series of Albiziabioside A derivatives and evaluated the antitumor activity both in vitro and in vivo. Compounds D13 possessed strong inhibitory activity against HCT116 cells with IC50 values of 5.19 μM. More importantly, compound D13 had a favorable selectivity and was efficacious against MDR cancer cells. Moreover, compound D13 could induce apoptosis and ferroptosis through the mitochondrial pathway as a p53 activator. In addition, compound D13 significantly suppressed tumorigenesis without inducing toxicity in normal organs in vivo. Collectively, this study provides a clinically relevant argument for considering triterpene saponin derivatives D13 as potential cancer therapeutic candidates with enhanced activity, acceptable safety and novel mechanisms of action. To the best of our knowledge, this compound is the first drug candidate which can induce apoptosis and ferroptosis as a p53 activator.