Chlorophyllin intervention reduces aflatoxin-DNA adducts in individuals athigh risk for liver cancer

Residents of Qidong, People's Republic of China, are at high risk for devel opment of hepatocellular carcinoma, in part from consumption of foods conta minated with aflatoxins. Chlorophyllin, a mixture of semisynthetic, water-s oluble derivatives of chlorophyll that is used as a food colorant and over- the-counter medicine, has been shown to be an effective inhibitor of Elf la toxin hepatocarcinogenesis in animal models by blocking carcinogen bioavail ability. In a randomized, double-blind, placebo-controlled chemoprevention trial, we tested whether chlorophyllin could alter the disposition of aflat oxin. One hundred and eighty healthy adults from Qidong were randomly assig ned to ingest 100 mg of chlorophyllin or a placebo three times a day for 4 months. The primary endpoint was modulation of levels of aflatoxin-N-7-guan ine adducts in urine samples collected 3 months into the intervention measu red by using sequential immunoaffinity chromatography and liquid chromatogr aphy-electrospray mass spectrometry. This aflatoxin-DNA adduct excretion pr oduct serves as a biomarker of the biologically effective dose of aflatoxin , and elevated levels are associated with increased risk of liver cancer. A dherence to the study protocol was outstanding, and no adverse events were reported. Aflatoxin-N-7-guanine could be detected in 105 of 169 available s amples. Chlorophyllin consumption at each meal led to an overall 55% reduct ion (P = 0.036) in median urinary levels of this aflatoxin biomarker compar ed with those taking placebo. Thus, prophylactic interventions with chlorop hyllin or supplementation of diets with foods rich in chlorophylls may repr esent practical means to prevent the development of hepatocellular carcinom a or other environmentally induced cancers.