By Lecia Bushak
Vitamin C, which is found in foods like oranges, bell peppers, broccoli, and papayas, has a variety of health benefits — from immune system protection to preventing against cardiovascular, eye disease, and skin wrinkles. Now, new research suggests that Vitamin C may also aid in the fight against cancer, particularly colorectal cancer.
The study, published in Science, focused primarily on colorectal cancer cells that had particularly mutations in KRAS and BRAF genes, which are involved in cell growth. When these mutated cells were exposed to high plasma levels of vitamin C, the researchers found that the cells take in the oxidized form of vitamin C through a certain receptor that happens to be over-expressed in mutated cells. As a result, the cancer cells undergo oxidative stress, turning off the enzyme necessary for the mutated cells to reproduce.
In the study, the researchers tested this out in mice; the vitamin C proved to destroy the mutated cancer cells. They note that Vitamin C could be useful because regular cancer therapies aren’t able to target the mutated cells.
“More than half of human colorectal cancers carry either KRAS or BRAF mutations, and are often refractory to approved targeted therapies,” the authors write in the abstract. “We report that cultured colorectal cancer cells harboring KRAS or BRAF mutations are selectively killed when exposed to high levels of vitamin C.”
It’s important to point out here, however, that it’s highly improbable the findings can actually be put to use. The notion that vitamin C can somehow stop cancer is highly contentious in the scientific world. Past research has examined the effect of vitamin C in cancer treatment since the 1970s, and the results are often contradictory. According to the National Cancer Institute, during cancer treatments, vitamin C is most effective if it’s administered via intravenous (IV) infusion, through a vein directly into the bloodstream. Some studies have shown that high doses of vitamin C may reverse the growth of prostate, pancreatic, liver, colon, and other kinds of cancer cells, but not many of these studies were later found to be flawed, according to the Mayo Clinic. However, some other researchers still believe that vitamin C therapy may be helpful in combination with other standard cancer treatments like chemotherapy or radiation.
Source: Yun J, Mullarky E, Lu C, Bosch K, Kavalier A, Rivera K. Vitamin C selectively kills KRAS and BRAF mutant colorectal cancer cells by targeting GAPDH. Science, 2015.