Thursday, December 10, 1998 Published at 11:15 GMT
Jaws treatment for cancer
Sharks have had some bad press, but they might save lives
Sharks, viewed as the killers of the deep, might actually be able to save lives if a new product to fight cancer proves successful.
US scientists are to test whether a product made from shark cartilage can starve cancer tumours of the blood supply they need to spread.
The US National Cancer Institute (NCI) and a Canadian biotechnology company are embarking on advanced trials of a product called Neovastat, a liquid cartilage extract.
Made by AEterna Laboratories in Canada, it is the first shark-derived product to be tested by the NCI, despite much pressure from alternative medicine supporters who believe sharks could offer a way forward for cancer treatment.
The interest in shark products was fuelled by a book which claimed the fish do not get cancer and could therefore provide the key to human cancer treatment.
However, scientists say sharks do get cancer, but the NCI has pledged to test shark products to see if they work.
The Phase III clinical trials of Neovastat - the last stage of testing before approval is sought from the US Food and Drug Administration - will involved 550 US and Canadian patients with advanced small cell lung cancer.
Dr James Pluda of the NCI said it was not surprising that cartilage, which cushions bones and joints, could cut off tumours' blood supply since it has no blood vessels.
However, scientists are not clear exactly how it works.
Sharks are thought to be an easy source of cartilage because they have no bones or skeletons.
Catlle cartilage has been shown to restrict the spread of cancer, but Dr Pluda said: "You've got to pick it off the bones and stuff."
Patients involved in the trials will be divided into two groups: those who get Neovastat along with chemotherapy and radiation treatment and those who get chemotherapy, radiotherapy and a placebo.
The researchers will then study their survival rate.
There are currently three other angiogenesis inhibitors - products which starve tumours of blood - in phase III trials.
Another shark product called squalamine is in the early stages of development. It is being tested on brain tumours.