Environmental and Molecular Mutagenesis (EMM) Editor's Choice - June 2013
The Editor's Choice for May is “Catalase has a Key Role in Protecting Cells from the Genotoxic Effects of Monomethylarsonous Acid: A Highly Active Metabolite of Arsenic” by Jorge G. Muniz Ortiz, Kathleen A. Wallace, Fabian Leinisch, Maria B. Kadiiska, Ronald P. Mason, and Andrew D. Kligerman.
Inorganic arsenic is considered to be one of the most potent carcinogens in our environment, and exposures to arsenic can result in cancer years later. Arsenic is found naturally in water, air, plants and animals, and unexpected high levels of arsenic were reported for rice. While arsenic has been known to be a human carcinogen for many years, there are still questions as to mechanisms of action. Dr. Kligerman and colleagues have been studying mechanisms of arsenic toxicity for many years and have previously reported that one of the key metabolites of arsenic, monomethylarsonous acid (MMAIII), will produce chromosome breaks and chromosome number changes in mammalian cells. In the present work the authors have found that genetically modifying levels of the enzyme catalase influences MMAIII genotoxicity; eliminating catalase leads to increased levels of DNA damage. These studies emphasize the importance of oxygen free radicals in arsenic toxicity, which in turn improves our understanding of the potential mode of arsenic carcinogenicity. Their work also supports the hypothesis that measuring individual variations in catalase activity might provide a biomarker of individual sensitivity to arsenic. Environ. Mol. Mutagen. doi: 10.1002/em.21780. © 2013 Wiley Periodicals, Inc.