http://www.news.com.au/dailytelegrap...006007,00.html
A 'GOLDEN bullet' treatment for cancer that tracks down tumours before wiping them out with a blast of heat is to be tested on patients within weeks, it has emerged.
The 'seek and destroy' technique uses an injection of microscopic glass spheres, coated in gold, which seek out potentially deadly cancers in the body.
Once enough spheres have flocked to the tumour, doctors 'activate' them using a low energy beam of light.
In tests, tumours have been totally destroyed.
Unlike conventional cancer treatments, the golden bullet approach uses no toxic chemicals and no radiation, reducing the risk of unpleasant side effects.
It could also be far cheaper - saving the NHS millions of pounds each year.
British cancer scientists welcomed the development and predicted that it could help tackle a range of potentially deadly diseases - from skin cancers to cancers of the cervix, breast, brain and neck.
Tests on mice found that the treatment works exceptionally well,
New Scientist magazine reports today.
When it was tried on nine mice with colon cancer, the tumours were destroyed.
Professor Jennifer West, of Rice University, Texas, who helped develop the treatment, said clinical trials on cancer patients are expected to begin in the U.S. 'within weeks'.
The first phase will find out whether the treatment successfully kills off tumours.
A second stage, due to start in a couple of years, will test the particles' ability to identify tumours.
"From the work we have done so far, we believe that this therapy will work on any soft-tissue tumours, such as the breast, prostate, brain, skin, head, neck and cervix," she said.
"In the animal studies we have not seen any side effects that would be cause for concern.
"Any side effects would be much less than we see for conventional treatments. And because it uses heat to kill tumours, rather than drugs to target part of a biological pathway, there is no opportunity for cancer cells to develop resistance to this treatment."
The golden bullet treatment is not the first to use 'nanoparticles'.
Past studies have shown that microscopic capsules injected into the bloodstream can deliver drugs directly to tumours.
What has excited scientists is that the technique identifies new tumours and destroys them minutes later with few side effects.
It uses 'nanospheres' - minute balls of glass around 140 millionths of a millimetre across, covered in gold.
These are injected into the bloodstream of a patient where they quickly circulate around the body.
The balls are designed to flow through healthy blood vessels.
However, the blood vessels that feed tumours are notoriously leaky.
Nanospheres that flow through one of these vessels will fall through the gaps in the vessel wall, and end up accumulating in the tumour.
If doctors pass a low-powered, infra-red light over an area where they have accumulated, they 'light up', allowing the location of the tumour to be spotted.
The area can then be bathed with a slightly more powerful infra-red light for three minutes.
The balls are designed to convert this light into heat - blasting away the surrounding cancerous tissue.
British cancer scientists welcomed the findings.
Dr Emma Knight, of Cancer Research UK, said: "The possibilities being thrown up by nanotechnology are truly exciting.
"Although this research is at a very early stage, we look forward to seeing the results of human trials later this year."
nanoparticle therapies
Linear Mode
