Decades ago, Linus Pauling suggested that vitamin C could treat many illnesses including cancer, but his theory was dismissed in the absence of successful clinical trials. Today, a new study found that vitamin C could indeed be an effective treatment against cancer, particularly colorectal cancer, according to Science News.
Researchers from Weill Cornell Medicine, Harvard Medical School, Cold Springs Harbor Laboratory, Johns Hopkins Kimmel Cancer Center and Tufts Medical Center discovered that vitamin C, when given in high doses, can treat colorectal cancer, specifically that which involves KRAS and BRAF mutant colorectal tumors.
KRAS and BRAF gene mutations comprise about half of colorectal cancer cases in the U.S. They are aggressive and difficult to treat because they do not respond well to chemotherapy. The researchers found that vitamin C, roughly equivalent to the amount of 300 oranges, kills colorectal cancer cells particularly with the KRAS and BRAF mutations in cell culture and mice.
While vitamin C is often hailed as an effective antioxidant, its beneficial effects against colon cancer are the opposite: it triggers oxidation, impairing the growth of KRAS and BRAF tumors that normally require antioxidants for survival.
Vitamin C in the body becomes oxidized and transforms into dehydroascorbic acid (DHA), which enters cells through a membrane protein called GLUT1. Antioxidants in cancer cells try to convert DHA back to ascorbic acid, getting depleted in the process. Oxidative stress then kills the cells.
"KRAS and BRAF mutant cells produce more reactive oxygen species than normal cells and therefore need more antioxidants in order to survive. This combination of characteristics makes these cancer cells far more vulnerable to DHA than normal cells or other types of cancer cells," lead study author Lewis Cantly from Weill Cornell Medicine said in a press release.
The results of the study could give way to new treatments that can target specific types of cancer.
"Our hope is that our study will inspire the scientific community to take a fresh look at this safe and inexpensive natural molecule and stimulate both basic and clinical research regarding vitamin C as a cancer therapy," study co-author Jihye Yun said in the press release.
The study was published in the Nov. 5 issue of the journal Science.
