The cytotoxicity of protoneodioscin (NSC-698789), a furostanol saponin from the rhizomes of Dioscorea collettii var. hypoglauca, against human cancer cells in vitro

Protoneodioscin (NSC-698789) is a furostanol saponin isolated from the rhizomes of Dioscorea collettii var. hypoglauca (Dioscoreaceae), a Chinese herbal remedy for Cancer treatment. Our studies showed that protoneodioscin is cytotoxic against most cell lines from leukemia and solid tumors in the NCI's (National Cancer Institute, USA) Anticancer drug screen. Leukemia, CNS Cancer, and prostate Cancer are the most sensitive subpanels to protoneodioscin, while melanoma, ovarian Cancer, and renal Cancer are less sensitive. The preliminary animal studies showed that the maximum tolerant dose of protoneodioscin was 600 mg/kg to mice. Based on an analysis of the COMPARE software with protoneodioscin as a seed compound, no compounds in the NCI's database have similar cytotoxicity patterns to those of protoneodioscin, indicating a potentially novel mechanism of Anticancer action involved.