Research studies effect of vitamin C on cancer cells
One of the most exciting areas of medicine today involves the use of stem cell therapy.
Stem cells may be beneficial for degenerative joint disease and chronic neurologic disorders and repairing damaged organs. It has been discovered that tumors also contain stem cell-like cells. These cells are responsible for tumors developing resistance to chemotherapy and radiation therapy as well the metastasis of cancer.
Some medical research has shown that cancer stem cells can be suppressed. Interestingly, vitamin C strongly suppresses cancer stem cell activity both in the test tube and probably in humans.
Cancer stem cells are believed to be most involved in the development of chemotherapy and radiation therapy resistance. These cells are ultimately responsible for treatment failure and metastasis in patients with advanced disease.
A successful anticancer therapy would not only address the normal cancer cells, but also try to inhibit the activity of cancer stem cells. There are a few experimental medications that do seem to suppress cancer stem cell activity, however vitamin C as well as an extract of milk thistle, silibinin, may be able to suppress cancer stem cell activity.
In a combined study done at the University of Manchester (England), University of Calabria (Italy) and the Albert Einstein College of Medicine demonstrated that cancer stem cell activity can be inhibited by both vitamin C and silibinin. Although the study was conducted in the test tube, it was discovered that these compounds interrupt an important metabolic pathway in cancer stem cells called the Krebs cycle.
The Krebs cycle is an important metabolic pathway for generating energy. Cancer stem cells seem to make more energy than normal cancer cells and so interrupting this important pathway significantly reduces cancer stem cell metabolic activity.
Several experimental drugs also affect the Krebs cycle in cancer stem cells, but these drugs can have significant side effects that would limit their use. In contrast, vitamin C and silibinin have very few side effects and in general are quite safe.
Although this individual study does not prove that select natural compounds are clinically effective in the treatment of cancer, it may help to explain some data involving vitamin C and cancer.
A large study published in Cancer Epidemiology, Biomarkers and Prevention demonstrated that taking vitamin C reduces the risk of mortality as well as recurrence (reducing cancer stem cell activity?) in patients diagnosed with breast cancer. In this study almost 5,000 women were followed for four years. Those women who began taking vitamin C within six months of their diagnosis had an 18 percent reduced mortality risk and a 22 percent reduced risk of recurrence.
Another study published in the European Journal of cancer involving over 17,000 women with breast cancer demonstrated a 19 percent reduced mortality risk. Interestingly, in this study vitamin C supplementation not only decreased the risk of dying from breast cancer but decreased the risk of overall mortality.
Although the studies are not definitive, they are highly suggestive that these alternative therapies may be "ready for prime time" in the war against cancer.
• Patrick B. Massey, MD, PH.D., is medical director for complementary and alternative medicine at Alexian Brothers Hospital Network and president of ALT-MED Medical and Physical Therapy, 1544 Nerge Road, Elk Grove Village. His website is www.alt-med.org.