Chlorophyllin May Reduce Risk of Liver Cancer

BALTIMORE--Chlorophyllin could bind aflatoxin, a cancer-causing agent, thereby reducing the risk of liver cancer, according to scientists at the Johns Hopkins Bloomberg School of Public Health and Oregon State University. The study, published in an early release and scheduled to appear in the next issue of the Proceedings of the National Academies of Science (www.pnas.org), focused on a population in Qidong, the People's Republic of China, because of an extreme risk of liver cancer due to aflatoxin contamination in that area--one in 10 adults dies of liver cancer in Qidong.

Aflatoxin is a chemical produced by mold that can infect grains and nuts if they are improperly stored in warm, moist areas. Inside the body, aflatoxin wreaks havoc on liver DNA, leaving a biomarker trail of aflatoxin-N7-guanine in the urine. Increased levels of this biomarker in the urine indicates an increased risk of liver cancer.

"Aflatoxin initiates cancer because it gets metabolized and forms a strong covalent chemical bond with certain parts of the DNA, in the liver particularly, and that causes mutational effects," said George Bailey, Ph.D., distinguished professor of toxicology at Oregon State University in Corvallis, Ore. "Over about a 24-hour period, most of that damage gets repaired out of the liver DNA, and those repair products appear in the urine."

In the randomized, double blind, placebo-controlled trial, researchers followed 180 healthy adults from Qidong who were randomly assigned to ingest 100 mg chlorophyllin or placebo three times daily for four months, as the derivative of chlorophyll has been linked to reduced DNA damage from aflatoxin in animal models. Chlorophyllin is a mixture of semisynthetic, water-soluble derivatives of chlorophyll, which are commonly used as a food colorant and in over-the-counter (OTC) medication.

"This is an important distinction because chlorophyll has a basic complex chemical ring structure and it has a big fatty acid side chain on it, making natural chlorophyll fat-soluble," Bailey explained. "You can treat [these rings] with an alkaline copper solution and hydrolyze off the fatty acid side chain and create acidic, or carboxylic, groups on this basic ring structure. So, it still looks green, still has the basic intact ring system, but now it is water-soluble rather than fat-soluble."

Bailey noted that this may be an important distinction in how chlorophyllin works and whether it has more than one mechanism of action. "There are several chemical carcinogens that have a chemical structure that is close to chlorophyllin, and this allows the chlorophyllin and the carcinogens to stick to each other," he said. "Basically, [chlorophyllin] allows a major portion of the dose of the carcinogen that might be in your stomach to just pass on through the system and not be absorbed."

To test results of supplementation, scientists studied urine samples for levels of aflatoxin-N7-guanine. The aflatoxin biomarker was detected in 105 of 169 available samples at three months. However, chlorophyllin consumption at each meal led to an overall 55 percent reduction in median urinary levels of the aflatoxin biomarker compared with those taking placebo. Researchers concluded that chlorophyllin may prevent the development of liver cancer or other cancers induced by environmental toxins.