Wednesday, February 3, 1999 Published at 12:31 GMT
Turning the tables on cancer
Conventional treatment is not very effective on pancreatic cancer
A cancer treatment which uses chemicals previously thought to cause the disease could be the key to treating thyroid and pancreatic cancer.
Cancer of the pancreas is one of the top 10 most common cancers and is very difficult to treat because it is often caught only in the late stages.
But scientists in Wales have found that treating pancreatic and thyroid cancer cells with chemicals known as Phorbol esters can cause them to self-destruct.
In the 1960s, laboratory tests on rats and mice showed that Phorbol esters, which are found in plant oils, could cause skin tumours.
But Professor David Wynford-Thomas and his team at the Cancer Research Campaign Thyroid Tumour Biology Research Group at the University of Wales in Cardiff have found that the chemicals also cause certain types of tumours to die.
Professor Wynford-Thomas says previous tests on the chemicals were down over a long time period.
He says a single dose of Phorbol esters can kill off some tumours, whilst not affecting normal cells.
The chemicals work by targetting a cancer-causing gene called ras, which is particularly prevalent in pancreatic and thyroid cancers.
Ras acts like a jammed accelerator, giving abnormal cells the signal to reproduce when they should not.
Phorbol esters cause the reproduction process to speed up to such a degree that the cells go into overdrive and implode.
Professor Wynford-Thomas said: "Most cancer treatments try to reverse the reproduction process, but this may only stop it for a while.
"The advantage of putting the cells into overdrive is that they die and cannot mutate further and the chemicals appear remarkably free of toxic effects."
He has been given £20,000 by the Cancer Research Campaign to develop his work over the next year.
He plans to look at what doses of the chemicals would be best for treating cancer tumours.
It is hoped that clinical trials on humans could be possible in a year or two.
The chemicals may also work on other forms of cancer which have a high level of ras in them, such as colon cancer which is one of the three most common cancers in the UK.
Professor Wynford-Thomas says the research has created a lot of interest from hospital specialists treating pancreatic cancer.
Professor Gordon McVie, director general of the Cancer Research Campaign, said the research is "marvellous".
"It really does turn conventional thinking upside down, but it is just the sort of ingenious approach to science which has helped the Campaign become Britain's leading cancer charity."