DALLAS, Oct. 16 (UPI) -- While antioxidants may be good for healthy people, researchers found they promote cancer growth in a study with mice.
The study, researchers said, echoes some other study results showing cancer patients' tumors actually grew while being treated with antioxidants.
The new study suggests cancer patients be treated with pro-oxidants, researchers at the University of Texas said.
"We discovered that metastasizing melanoma cells experience very high levels of oxidative stress, which leads to the death of most metastasizing cells," said Dr. Sean Morrison, CRI Director and Mary McDermott Cook Chair in Pediatric Genetics at UT Southwestern Medical Center, in a press release. "Administration of antioxidants to the mice allowed more of the metastasizing melanoma cells to survive, increasing metastatic disease burden."
Metastasis, the spread of cancer from a primary tumor to another location in the body, is inefficient and cancer cells often do not survive in the bloodstream.
Researchers at UT, testing prevention of metastasis in mice, transplanted human melanoma cells to mice, treating some with antioxidants and some without. They found cancer in the mice that received antioxidants spread more quickly than in mice that did not receive the treatment.
The researchers wrote in the study that treating cancer patients with pro-oxidants may be a better path because oxidative stress limits metastasis, based on the results of work with melanoma cells in the lab.
"The idea that antioxidants are good for you has been so strong that there have been clinical trials done in which cancer patients were administered antioxidants," added Dr. Morrison, who is also a CPRIT Scholar in Cancer Research and a Howard Hughes Medical Institute Investigator. "Some of those trials had to be stopped because the patients getting the antioxidants were dying faster. Our data suggest the reason for this: cancer cells benefit more from antioxidants than normal cells do."
The study is published in Nature.