by Lyndsay Moss
Spanish version
05 August 2008
from
ScotsmanNews Website
INJECTIONS of vitamin
C could halve the growth of cancerous tumors, research suggested
yesterday.
A study in the United States found that the vitamin could prove
useful in treating cancers for which few other options currently
exist. The breakthrough, which comes following tests on mice,
follows decades of research into the potential of
vitaADVERTISEMENTmin C in tackling cancer. However, experts warned
that the benefits of the vitamin had yet to be demonstrated in human
patients.
For the latest study, researchers from the National Institutes of
Health in Bethesda, Maryland, examined the effects of vitamin C on
cells grown in laboratories. Two hours of exposure to the vitamin
significantly cut the survival of ovarian, pancreatic and brain
tumor (glioblastoma) cancer cells.
Similar results were seen when cancer-ridden mice were injected with
vitamin C. The therapy halved the growth of aggressive tumors,
killing cancer cells while leaving healthy tissue unharmed.
It is thought the discovery could provide a new lifeline for
patients with a poor prognosis and few other options. Tackling
cancer with vitamin C would also have the added advantage of being
cheap compared with many of the very expensive cancer treatments.
Usually the body keeps a tight rein on high vitamin C levels in the
blood. But the scientists found that the mechanism can be by-passed
if the vitamin is injected straight into the blood instead of
passing through the digestive system. When this is done it releases
the powerful anti-cancer potential of the vitamin, according to the
researchers writing in the journal Proceedings of the National
Academy of Sciences.
The experiments showed that high levels of vitamin C in the blood
generate hydrogen peroxide, which is lethal to tumors. The
chemical forms in the spaces between cancer cells, damaging
membranes, upsetting metabolism and scrambling the DNA of the tumor.
Even the growth of aggressive cancers was held back in the
experiments. But healthy tissues appeared to resist the effects.
The use of high-dose vitamin C as an alternative cancer treatment
has a long history dating back to the 1970s. Patients have taken the
vitamin both by mouth and intravenously, but with mixed results in
scientific trials. For this reason, claims that vitamin C can treat
cancer have been dismissed by conventional cancer experts. But the
new investigation, led by Dr Qi Chen, may help to start
changing attitudes towards this approach.
The scientists said:
"Pharmacologic
concentrations of ascorbate (the chemical name for
vitamin C] decreased tumor volumes 41-53 per cent in diverse
cancer types known for both their aggressive growth and limited
treatment options."
Dr Alison Ross, science
information officer at Cancer Research UK, said:
"This is encouraging
work but it's at a very early stage because it involves cells
grown in the lab and mice."
Cancer hopes as...
Vitamin C injections kill mice tumors
by William Tinning
August 05 2008
from
TheHerald Website
Vitamin C that is
injected rather than swallowed could provide a new lifeline for
cancer patients with a poor prognosis and few treatment options,
according to new research. Scientists say the therapy halved the
growth of aggressive tumors in mice, killing cancer cells while
leaving healthy tissue unharmed.
Tackling cancer with vitamin C would also have the added advantage
of being less expensive, the research claims. The body usually keeps
tight control of vitamin C levels in the blood.
However, a new US-based investigation, led by Dr Qi Chen from
the National Institutes of Health in Maryland, Ohio, found
that the mechanism can be by-passed if the vitamin is injected
straight into the bloodstream instead of passing through the
digestive system. When this is done it releases the powerful
anti-cancer potential of the vitamin.
Experiments showed that high levels of vitamin C in the blood
generate hydrogen peroxide, which is lethal to tumors. The
chemical forms in the spaces between cancer cells, damaging
membranes, upsetting metabolism and scrambling DNA.
Even the growth of aggressive, hard-to-treat cancers was held back
in the studies. But healthy tissues appeared to resist the effects.
The use of high-dose vitamin C as a complementary or alternative
cancer treatment was first promoted in the 1970s. Patients have
taken the vitamin both by mouth and intravenously. But despite some
positive outcomes, there has been insufficient reliable evidence
that the therapy works leading conventional cancer experts to
dismiss claims that vitamin C can treat cancer.
Dr Chen's investigation involved testing the effects of vitamin C on
laboratory cell lines and cancer-ridden mice. Laboratory tests
showed that two hours of exposure to the vitamin significantly
reduced the survival of ovarian, pancreatic and brain tumor cancer
cells. Similar results were achieved when mice bearing the same
kinds of tumors were injected with vitamin C.
Writing in the journal Proceedings of the National Academy of
Sciences, the scientists said:
"Pharmacologic
concentrations of ascorbate decreased tumor volumes
41-53% in diverse cancer types known for both their aggressive
growth and limited treatment options."
They said a "rapid and
sustained increase" in hydrogen peroxide was detected in tumor
fluids within 30 minutes of the treatment commencing.
An early stage patient study showed that similar therapeutic levels
of vitamin C in the blood could be achieved when ascorbate
was administered intravenously in humans.
The scientist added:
"A regimen of daily
pharmacologic ascorbate treatment significantly decreased
growth rates of ovarian, pancreatic and glioblastoma
tumors established in mice.
"Similar pharmacologic concentrations were readily achieved in
humans given ascorbate intravenously. These data suggest
that ascorbate as a prodrug may have benefits in
cancers with poor prognosis and limited therapeutic options."
Dr Alison Ross,
science information officer at Cancer Research UK, said:
"This is encouraging
work but it's at a very early stage because it involves cells
grown in the lab and mice. Much more research is needed before
we'll know whether vitamin C could be a viable cancer treatment
in the future.
"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."
Vitamin C supplements
have been hailed since the 1970s as an aid for fighting colds,
principally thanks to the US Nobel Prizewinning chemist Dr Linus
Pauling, who championed it.
However, in July last year, Australian and Finnish scientists
describe d the claim as a myth, saying that there was no evidence
that, for the average person, taking extra vitamin C can stop
coughs and sneezes.
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