http://news.bbc.co.uk/1/hi/health/7540822.stm
Just in case anyone missed this.
Vitamin C 'slows cancer growth'
TREATMENT IMPACT
See the impact of vitamin C treatment on mice with tumours. Warning: the image may disturb.
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An injection of a high dose of vitamin C may be able to hold back the advance of cancers, US scientists claim.
The vitamin may start a destructive chain reaction within the cancer cell, they add.
The jab halved the size of brain, ovarian and pancreatic tumours in mice, reported the journal Proceedings of the National Academy of Sciences.
However, Cancer Research UK said other studies suggested large vitamin C doses may interfere with cancer treatment.
This is encouraging work but it's at a very early stage because it involves cells grown in the lab and mice
Dr Alison Ross
Cancer Research UK
Earlier research by the team at the National Institutes of Health in Maryland had suggested that the vitamin, also called ascorbate, could kill cancer cells in the laboratory.
After these successful tests in mice, they are now suggesting that the treatment be considered for human use at similar levels.
The dose they employed - up to four grams per kilo of bodyweight - was far greater than any that could be achieved using diet or vitamin pills, as the digestive system does not absorb more than a fixed amount taken orally.
The mice were bred to have malfunctioning immune systems, then injected with human cancer cells, which as a result, grew quickly into large tumours. The vitamin was then injected into their abdominal cavity.
Tumour growth and weight fell by between 41% and 53%, and while in untreated mice, the disease spread rapidly to involve other body parts, no such spread was seen in the vitamin C-treated animals.
The researchers wrote: "These pre-clinical data provide the first firm basis for advancing pharmacologic ascorbate in cancer treatment in humans."
Peroxide bomb
The treatment works because a tumour cell is chemically different to a healthy cell.
The vitamin C reacts with this chemical make-up, producing enough hydrogen peroxide to kill the cell, while leaving healthy cells unscathed.
However, Dr Alison Ross, from Cancer Research UK said that much more work would have to be done to see if vitamin C could be a viable treatment.
"This is encouraging work but it's at a very early stage because it involves cells grown in the lab and mice.
"There is currently no evidence from clinical trials in humans that injecting or consuming vitamin C is an effective way to treat cancer.
"Some research even suggests that high doses of antioxidants can make cancer treatment less effective, reducing the benefits of radiotherapy and chemotherapy."
Earlier from the BBC:
Vitamin C 'helps to fight cancer'
oranges
High dose vitamin C injected into the bloodstream help fight cancer
High doses of vitamin C injected into the bloodstream may help fight cancer, a US study says.
Scientists found that intravenous vitamin C in the form of ascorbate killed cancer cells in lab tests.
The findings contradict earlier studies, but the Maryland-based Institutes of Health said they had looked at lower-dose oral vitamin C.
Cancer experts said the "overwhelming" evidence still suggested vitamin C was not an effective treatment.
Studies in the 1970s first suggested the administration of high doses of vitamin C could help treat cancer, but later research did not back this up.
There are many substances that have been shown to kill cancer cells in the lab but failed to fulfil that promise when tested in people
Henry Scowcroft, of Cancer Research UK
In the latest study, published in the Proceedings of the National Academy of Sciences, researchers conducted laboratory experiments which simulated clinical infusions of vitamin C on a range of nine cancer and four normal cells.
In five of the cancer lines, there was a 50% decrease in cell survival, while normal cells were unaffected.
A more detailed look at lymphoma cells - which were especially sensitive to ascorbate - showed they were killed completely.
The effective dose was around four millimoles, a concentration much higher than an oral dose but easily achievable by intravenous infusion.
Cells
Researchers were unable to explain what caused the results, although they did note the treatment led to the formation of hydrogen peroxide, a chemical known to be toxic to cells.
Alternative medicine practitioners have already administered high doses of intravenous ascorbate.
Lead researcher Dr Mark Levine said the treatment would have to be proved safe before being given to patients.
But he added: "Ascorbate as a potential cancer therapeutic agent has a controversial and emotionally charged past."
Henry Scowcroft, senior information officer at Cancer Research UK, said despite the findings, the "overwhelming" evidence still pointed to vitamin C not being an effective treatment.
"This work is at a very early stage. There are many substances that have been shown to kill cancer cells in the lab, but failed to fulfil that promise when tested in people.
"But we do know that eating a healthy, balanced diet, including plenty of fresh fruit and vegetables, is an effective way to reduce the risk of getting cancer in the first place." http://news.bbc.co.uk/1/hi/health/4238250.stm
Earlier from the BBC:
http://news.bbc.co.uk/1/hi/health/4238250.stm
Vitamin C 'helps to fight cancer'
oranges
High dose vitamin C injected into the bloodstream help fight cancer
High doses of vitamin C injected into the bloodstream may help fight cancer, a US study says.
Scientists found that intravenous vitamin C in the form of ascorbate killed cancer cells in lab tests.
The findings contradict earlier studies, but the Maryland-based Institutes of Health said they had looked at lower-dose oral vitamin C.
Cancer experts said the "overwhelming" evidence still suggested vitamin C was not an effective treatment.
Studies in the 1970s first suggested the administration of high doses of vitamin C could help treat cancer, but later research did not back this up.
There are many substances that have been shown to kill cancer cells in the lab but failed to fulfil that promise when tested in people
Henry Scowcroft, of Cancer Research UK
In the latest study, published in the Proceedings of the National Academy of Sciences, researchers conducted laboratory experiments which simulated clinical infusions of vitamin C on a range of nine cancer and four normal cells.
In five of the cancer lines, there was a 50% decrease in cell survival, while normal cells were unaffected.
A more detailed look at lymphoma cells - which were especially sensitive to ascorbate - showed they were killed completely.
The effective dose was around four millimoles, a concentration much higher than an oral dose but easily achievable by intravenous infusion.
Cells
Researchers were unable to explain what caused the results, although they did note the treatment led to the formation of hydrogen peroxide, a chemical known to be toxic to cells.
Alternative medicine practitioners have already administered high doses of intravenous ascorbate.
Lead researcher Dr Mark Levine said the treatment would have to be proved safe before being given to patients.
But he added: "Ascorbate as a potential cancer therapeutic agent has a controversial and emotionally charged past."
Henry Scowcroft, senior information officer at Cancer Research UK, said despite the findings, the "overwhelming" evidence still pointed to vitamin C not being an effective treatment.
"This work is at a very early stage. There are many substances that have been shown to kill cancer cells in the lab, but failed to fulfil that promise when tested in people.
"But we do know that eating a healthy, balanced diet, including plenty of fresh fruit and vegetables, is an effective way to reduce the risk of getting cancer in the first place."
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