Vitamin C injections slow tumor growth in mice

August 4, 2008

High-dose injections of vitamin C, also known as ascorbate or ascorbic acid, reduced tumor weight and growth rate by about 50 percent in mouse models of brain, ovarian, and pancreatic cancers, researchers from the National Institutes of Health (NIH) report in the August 5, 2008, issue of the Proceedings of the National Academy of Sciences. The researchers traced ascorbate's anti-cancer effect to the formation of hydrogen peroxide in the extracellular fluid surrounding the tumors. Normal cells were unaffected.

Natural physiologic controls precisely regulate the amount of ascorbate absorbed by the body when it is taken orally. "When you eat foods containing more than 200 milligrams of vitamin C a day--for example, 2 oranges and a serving of broccoli--your body prevents blood levels of ascorbate from exceeding a narrow range," says Mark Levine, M.D., the study's lead author and chief of the Molecular and Clinical Nutrition Section of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the NIH.

To bypass these normal controls, NIH scientists injected ascorbate into the veins or abdominal cavities of rodents with aggressive brain, ovarian, and pancreatic tumors. By doing so, they were able to deliver high doses of ascorbate, up to 4 grams per kilogram of body weight daily. "At these high injected doses, we hoped to see drug-like activity that might be useful in cancer treatment," said Levine.

Vitamin C plays a critical role in health, and a prolonged deficiency leads to scurvy and eventually to death. Some proteins known as enzymes, which have vital biochemical functions, require the vitamin to work properly. Vitamin C may also act as an antioxidant, protecting cells from the damaging effects of free radicals. The NIH researchers, however, tested the idea that ascorbate, when injected at high doses, may have prooxidant instead of antioxidant activity. Prooxidants would generate free radicals and the formation of hydrogen peroxide, which, the scientists hypothesized, might kill tumor cells. In their laboratory experiments on 43 cancer and 5 normal cell lines, the researchers discovered that high concentrations of ascorbate had anticancer effects in 75 percent of cancer cell lines tested, while sparing normal cells. In their paper, the researchers also showed that these high ascorbate concentrations could be achieved in people.

The team then tested ascorbate injections in immune-deficient mice with rapidly spreading ovarian, pancreatic, and glioblastoma (brain) tumors. The ascorbate injections reduced tumor growth and weight by 41 to 53 percent. In 30 percent of glioblastoma controls, the cancer had spread to other organs, but the ascorbate-treated animals had no signs of disseminated cancer. "These pre-clinical data provide the first firm basis for advancing pharmacologic ascorbate in cancer treatment in humans," the researchers conclude.

Interest in vitamin C as a potential cancer therapy peaked about 30 years ago when case series data showed a possible benefit. In 1979 and 1985, however, other researchers reported no benefit for cancer patients taking high oral doses of vitamin C in two double-blind, placebo-controlled clinical trials.

Several observations led the NIH researchers to revisit ascorbate as a cancer therapy. "Clinical and pharmacokinetic studies conducted in the past 12 years showed that oral ascorbate levels in plasma and tissue are tightly controlled. In the case series, ascorbate was given orally and intravenously, but in the trials ascorbate was just given orally. It was not realized at the time that only injected ascorbate might deliver the concentrations needed to see an anti-tumor effect," said Levine, who noted that new clinical trials of ascorbate as a cancer treatment are in the planning stages.

Data from Levine's earlier studies of the regulation and absorption of dietary vitamin C were used in the revision of the Institute of Medicine's Recommended Dietary Allowance for the vitamin in 2000. In the current study, Levine led a team of scientists from the NIDDK and the National Cancer Institute (NCI), both components of the NIH, as well as the University of Kansas. "NIH's unique translational environment, where researchers can pursue intellectual high-risk, out-of-the-box thinking with high potential payoff, enabled us to pursue this work," he said.

Source: National Institute of Diabetes and Digestive and Kidney Diseases

Explore further: Scientists discover vitamin C regulates stem cell function, curbs leukemia development

Related Stories

Scientists discover vitamin C regulates stem cell function, curbs leukemia development

August 21, 2017
Not much is known about stem cell metabolism, but a new study from the Children's Medical Center Research Institute at UT Southwestern (CRI) has found that stem cells take up unusually high levels of vitamin C, which then ...

Vitamin C halts growth of aggressive forms of colorectal cancer in preclinical study

November 6, 2015
High levels of vitamin C kill certain kinds of colorectal cancers in cell cultures and mice, according to a new study from Weill Cornell Medicine investigators. The findings suggest that scientists could one day harness vitamin ...

Vitamin C effective in targeting cancer stem cells

March 8, 2017
Vitamin C is up to 10 times more effective at stopping cancer cell growth than pharmaceuticals such as 2-DG, according to scientists in Salford, UK.

Why high-dose vitamin C kills cancer cells

January 9, 2017
Vitamin C has a patchy history as a cancer therapy, but researchers at the University of Iowa believe that is because it has often been used in a way that guarantees failure.

Could additives in hot dogs affect incidence of colon cancer?

October 24, 2011
The addition of ascorbate (vitamin C) or its close relative, erythorbate, and the reduced amount of nitrite added in hot dogs, mandated in 1978, have been accompanied by a steep drop in the death rate from colon cancer, according ...

Breast cancer cells use newfound pathway to survive low oxygen levels in tumors

June 20, 2016
Researchers have identified a new signaling pathway that helps cancer cells cope with the lack of oxygen found inside tumors. These are the results of a study published in Nature Cell Biology on June 20, and led by researchers ...

Recommended for you

Engineered protein treatment found to reduce obesity in mice, rats and primates

October 19, 2017
(Medical Xpress)—A team of researchers with pharmaceutical company Amgen Inc. report that an engineered version of a protein naturally found in the body caused test mice, rats and cynomolgus monkeys to lose weight. In their ...

New procedure enables cultivation of human brain sections in the petri dish

October 19, 2017
Researchers at the University of Tübingen have become the first to keep human brain tissue alive outside the body for several weeks. The researchers, headed by Dr. Niklas Schwarz, Dr. Henner Koch and Dr. Thomas Wuttke at ...

Cancer drug found to offer promising results in treating sepsis in test mice

October 19, 2017
(Medical Xpress)—A combined team of researchers from China and the U.S. has found that a drug commonly used to treat lung cancer in humans offers a degree of protection against sepsis in test mice. In their paper published ...

Tracing cell death pathway points to drug targets for brain damage, kidney injury, asthma

October 19, 2017
University of Pittsburgh scientists are unlocking the complexities of a recently discovered cell death process that plays a key role in health and disease, and new findings link their discovery to asthma, kidney injury and ...

Study reveals key molecular link in major cell growth pathway

October 19, 2017
A team of scientists led by Whitehead Institute has uncovered a surprising molecular link that connects how cells regulate growth with how they sense and make available the nutrients required for growth. Their work, which ...

Inflammation trains the skin to heal faster

October 18, 2017
Scars may fade, but the skin remembers. New research from The Rockefeller University reveals that wounds or other harmful, inflammation-provoking experiences impart long-lasting memories to stem cells residing in the skin, ...

3 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

irjsi
5 / 5 (1) Aug 04, 2008
How can terminal patients access "C"
injections?
Benign side effects would be little
deterrent to one with a diminishing
time frame!
Also, administer ASAP post-diagnosis;
prior to debilitating effects resulting
from current treatment regimen.
Roy Stewart,
Phoenix AZ
E_L_Earnhardt
1 / 5 (1) Aug 05, 2008
I'll bet "COOL WATER" would do the same! Tap off the ENERGY and you slow mitosis! Nevertheless, USE it! ANYTHING THAT WORKS!
Northerntracey
5 / 5 (1) Aug 13, 2008
I am amazed at the gall of the media. Not only this paper but all the other touting this so-called "breakthrough research". It has been well known for many years that intravenous VitC can save cancer patients lives. Clinical trials? No need. Just visit some of the many banned clinics ousted from America to Mexico where they have been saving lives for years. Where were the papers then. How many more lives could have been saved if not for the media blackout of many other 'alternative' therapies that work like DMSO, MMS, Becks protocol, Gerson Therapy etc etc.
It's about time people woke up to what is going on with the whole medical 'racket'.
And what now of the proposed ban on VitC supplements in Canada coming from Codex?
Or is that all part of another plan for profits to Big Pharma?

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.