Can Vitamins Fight Cancer?
What scientists know – and don’t know – about treating cancer with nutrients.
Hydroxyurea. Mercaptopurine. Cyclophosphamide. One thing all cancer drugs seem to have in common is their hard-to-spell names.
Or do they? How about A? D? E? These aren’t fancy new drugs – they’re plain old vitamins. Yet, when administered by scientists in large doses, some vitamins may act like drugs, or work with standard cancer-fighting drugs. It isn’t clear yet whether the research into this futuristic notion of vitamin chemo-therapy will ever pan out. But if the research is successful, chemotherapy could be much easier to take – and a lot easier to spell.
Here’s what scientists have learned so far:
BATTLING IN THE BLOODSTREA
Synthetic versions of vitamins A and D seem to hold promise in the treatment of myeloid leukemia, a cancer of white blood cells.
The main problem in leukemia is that immature white blood cells proliferate in the bloodstream, crowding out normal red and white cells. This causes severe anemia and comprises the immune system. But through a hormonal interaction, vitamins A and D seem to make the immature cells grow up. Mature cells appear to stop their rapid reproduction and are able to carry out their immune-system functions.
Initially the active form of vitamin D was tested, but in high doses this has the unfortunate side-effect of causing the body to retain calcium. That could cause complications, including hardening of the vital organs and death. But the synthetic version of vitamin D has a more powerful maturing influence on leukemia cells – and a much-lowered calcium-loading mechanism.
In studies on leukemia lab mice, this synthetic compound achieved much better results than pure vitamin D. “Some of the mice treated with synthetic D may actually be cured of their leukemia,” reports H. Phillip Koeffler, M.D., professor of medicine at UCLA and one of the leading researchers in this field.
Synthetic vitamin A has been tested in humans against leukemia, but not on a very widespread scale. A few years ago, American researchers at several different medical centers were involved in a double-blind, randomized trial of 13-cisretinoic acid (a retinoid compound) in patients with a pre-leukemia condition called myelodysplastic syndrome. Problems with the study – including many patients quitting the trial – cast suspicion on the results, according to Dr. Koeffler.
One of the researchers, however, continued the study on his own after the trial ended, and found a significant response. Was the original trial too short? It’s hard to say without attempts to duplicate those results. The study also showed physicians that the side-effects of retinoid therapy drying can be reduced with doses of vitamin E.
More reports have come from other countries. Researchers in China and France have reportedly achieved promising results using trans retinoic acid (ATRA) against acute promyelocytic leukemia (APL). Most of the patients in Chinese studies went to remission. A French researcher has reportedly duplicated their results.
Other research shows that of seven APL patients (from four different studies) treated with isotretinoin, four had what was termed “remarkable responses.” Clearly, there’s enough evidence to warrant further research on both synthetic A and D.