Cliffs: Gene therapy cures two men with advanced melanoma. Cancer-free for 18 months now.
http://www.theage.com.au/news/national/gene-therapy-cures-cancer/2006/09/01/1156817099219.html
AUSTRALIAN cancer experts have hailed the work of US scientists who cured two men of advanced melanoma with gene therapy.
In one of the most promising developments in cancer therapy for years, scientists successfully “trained” the immune cells of two patients to destroy their tumours. It is the first time gene therapy has been used to successfully treat cancer.
“This is very exciting,” said Professor Ian Olver, the Cancer Council of Australia’s chief executive officer. “If this sort of success keeps up it won’t be long before all sorts of people are investigating (cancer treatments) along those lines.”
The US team, led by respected scientist Dr Steven Rosenberg, treated 17 patients, but the treatment only worked on two, who have been cancer-free for 18 months. The experiment targeted advanced melanoma, which kills 220 Victorians each year, but the scientists believe their method holds promise for other cancers.
The treatment, published in the journal Science, involved taking a type of white blood cell, called a T cell, from the patients, then adding a virus containing a gene that allows the cells to better recognise tumours. Sometimes tumours are too much like the body it comes from, and the immune system fails to recognise it as foreign.
After being charged-up and manipulated, billions of the cells were put back in the patients to find the enemy tumours.
Scientists welcomed the development yesterday, although many are wary, as gene therapy has promised much and delivered little. But gene therapy expert Ashley Dunn, an honorary professor at the University of Melbourne, said the science should be given extra weight as it came from the laboratory of Dr Rosenberg: “This is not a guy with a track record of hype, this is a guy with a track record of action,” he said, but added it was difficult to prove a certain therapy was why a patient survived.
Professor Dunn said it was difficult to tell how long the new boosted-up immune cells would last in a person’s body once they were returned. The 15 patients who did not respond to the treatment did not keep the cells in their body as long as the two that did.
Professor Olver said the development was “a potential advance rather than an actual advance”, which could not help people living with advanced melanoma.
During the study tumours shrank in other participants, all of whom had exhausted other forms of treatment. Dr Rosenberg said: “It is the first time, with all the hype of gene therapy, we have managed to use genetic engineering to treat cancer patients.”
Dr Rosenberg has found a more potent class of receptors, up to 100 times more effective at helping immune cells attack the cancer.
“We have now expressed other lymphocyte receptors that recognise breast, lung, and other cancers,” he said. “They are present on half of all common cancers. We can, with these powerful receptors, convert any patient’s normal cells into cells that will recognise these common cancers.”
Trials will start in a month, subject to approval by US authorities.