To obtain water-soluble holothurian
glycosides with high
tumor suppressing activities from Apostichopus japonicus, macroporous resin,
silica gel and gel-filtration column chromatograghy were used to purify the water-soluble holothurian
glycosides, and their
tumor suppressing activity and inducing apoptosis of
tumor cells were examined in this study. The 70%
ethanol fraction of macroporous resin column, the pSC-2 and pSC-3 fractions from
silica gel column showed very strong
tumor suppressing activity towards HeLa cells, A-549
lung cancer cells, SGC-7901
stomach cancer cells and Bel-7402
liver cancer cells. SC-2 and SC-3 fraction purified from
Sephadex LH-20 gel-filtration column chromatography, with a purity above 99.6%, all had the properties of
triterpenoid glycosides. Purified SC-2 fraction had remarkable
tumor suppressing activity on HeLa cells in a dose- and time-dependent manner, and had prominent
tumor suppressing activity to mouse S180 solid
tumors in a dose-dependent manner. Besides, the SC-2 fraction also had remarkable ability in elevating mouse thymus index and spleen index. The purified SC-2 fraction could induce apoptosis of HeLa cells in a dose-dependent manner, and DNA fragmentation of HeLa cells occurred after treated 12 h with 10 mg x L(-1) and 50 mg x L(-1) of SC-2 fractions. From the results, it can be concluded that the purified SC-2 fraction of water-soluble holothurian
glycosides has extremely strong
tumor suppressing activity, and the suppression is realized by inducing
tumor cells to undergo apoptosis. This study lays solid foundation for development of highly effective new natural
anticancer agents from sea cucumbers.