[Anti-tumor marine natural products]

In anticipation of developing new anti-cancer drugs from marine organisms of rich species, a variety of anti-tumor substances having diverse chemical structures have been discovered. Among those marine anti-tumor substances, which were reviewed in a previous paper [Jpn. J. Cancer Chemother., 16, 1-8 (1989)], several compounds promising as anti-cancer drugs are detailed in this article. They are didemnin B from marine tunicate, bryostatin 1 from marine bryozoa, and dolastatin 10 from sea hare. In addition, several anti-tumor marine sponge constituents: halichondrin B, calyculin A, and mycalamides A and B, are briefly reviewed.