Antitumor activity of C-21 steroidal glycosides from Cynanchum auriculatum Royle ex Wight.

ABSTRACT

The antitumor activities of six C-21 steroidal glycosides isolated from the root tuber of Cynanchum auriculatum Royle ex Wight were performed according to a microculture tetrazolium (MTT) method on human tumor cell lines SMMC-7721, MCF-7 and Hela. Of these compounds, caudatin-2,6-dideoxy-3-O-methy-ß-D-cymaropyranoside and caudatin were found to be of the highest effects against human tumor cell line SMMC-7721 with IC(50) values of 13.49 and 24.95 µM, respectively. Then the in vivo assay further showed that caudatin-2,6-dideoxy-3-O-methy-ß-D-cymaropyranoside and caudatin significantly inhibited the growth of transplantable H(22) tumors in mice.