Deciphering Functions of Intracellular Formaldehyde - Linking Cancer and Aldehyde Metabolism

[First paragraph]Formaldehyde, the simplest aldehyde, is an environmental pollutant and human toxin. Acute exposure to exogenous formaldehyde can cause irritation, nausea, renal failure, and coma. Chronic formaldehyde exposure correlates with increased cancer incidence, in particular of nasopharyngeal cancer and leukemia. In addition to exogenous sources, formaldehyde is produced endogenously in cells; eukaryotic pathways producing formaldehyde include xenobiotic metabolism and enzyme-catalyzed N-methyl demethylation of the N-methylated histone and DNA components of chromatin, as well as of RNA. Thus, endogenously produced formaldehyde may have biological roles; there have been very few studies connecting the biochemistry of formaldehyde with physiology.