Cancer researchSubstances from marine corals and sponges are being examined by scientists who believe they could inspire new anti-cancer drugs, the BA festival heard yesterday.
"Natural products really are the best starting point for new drugs," said Prof John Mann, a medicinal chemist at Queen's University Belfast. "If you want a drug against malaria, for example, and you can find a naturally occurring substance that interacts with the cause of the disease - you can take that structure and try to optimise it."
Prof Mann's research focuses on finding new anti-cancer drugs, he said. About 50 per cent of current drugs are either derived from natural products or have structure based on natural products, said Prof Mann.
Although in the last 10 years pharmaceutical companies have focused more on devising new drugs de novo, there has recently been a resurrection of interest in natural products, he said.
Prof Mann is investigating the potential anti-cancer agent eleutherobin from a rare Australian soft coral found off the coast of Perth. Eleutherobin is promising because it acts in a similar way to the existing cancer drug Taxol but seems to be 100 times as potent, he said.
The substance has only been tested on cancer cells in the laboratory, but has shown good activity against 20 to 30 different cell lines, explained Prof Mann. As eleutherobin is produced in very small amounts from the coral, he is currently working to build a synthetic version that could form the basis of a new drug. "We have made the left side of the basic skeleton and the right side and we are trying to stitch them together chemically," he added.
"We can then 'embroider' the basic skeleton with side chains to try and make a structure that has similar effects to eleutherobin."
The basic skeleton, and various versions of it, will then be tested against the cancer cell lines in the laboratory, in an attempt to replicate or exceed the effects observed with the natural product, he said.
Other anti-cancer drugs with marine origins are being investigated, Prof Mann added. Bryostatin originates from a marine organism found off the coast of California, and discodermolide from a species of sponge. Both are currently undergoing early, phase I clinical trials.