Summary
A recent study has shed new light on formaldehyde, a known carcinogen in various environmental sources. Surprisingly, this molecule also plays an essential role in our bodies, regulating our genes and possibly explaining its cancer-causing properties.
Formaldehyde, a toxin and carcinogen found in numerous environmental sources such as construction materials, car exhaust, and cigarette smoke, has a dual role in the human body, according to a recent study published in Science. Researchers from the University of California, Berkeley, and the University of Oxford reported that formaldehyde inhibits DNA methylation, an essential epigenetic process in our bodies that controls gene expression.
“The broader implication of our study is that it provides a biochemical mechanism for how formaldehyde might be a carcinogen… We showed that altering your body’s internal formaldehyde levels can also change your epigenetics, reprograming cancer.” – Christopher Chang, UC Berkeley professor of chemistry and molecular and cell biology.
Formaldehyde: Not Just an Environmental Toxin
Previous studies have shown that formaldehyde, in large quantities, can turn off DNA by causing crosslinks. However, these studies didn’t explain the toxicity of small amounts of formaldehyde. Chang and his team have unveiled that formaldehyde, produced by the body in small quantities, regulates epigenetic changes. This discovery suggests that excess formaldehyde may suppress the body’s efforts to control the expression or overexpression of specific genes, potentially leading to cancer.
Formaldehyde and One-Carbon Metabolism
Chang and his colleagues embarked on a study exploring formaldehyde — represented chemically as CH2O — after discovering that it is produced inside the body. DespitChang remained despite the contradiction of delivering a known toxin within our bodies. He compared formaldehyde to reactive oxygen species or nitric oxide, where small amounts benefit the body, but excessive quantities can be harmful.
The Role of Formaldehyde in Gene Regulation
Using a chemical proteomics approach, the research team identified an exciting pathway where formaldehyde regulates a whole class of biochemistry known as one-carbon metabolism. They found that formaldehyde inhibits an enzyme that generates another one-carbon molecule, S-adenosylmethionine, which acts as a source of methyl groups attached to DNA to modulate the expression of specific genes. This discovery implies that formaldehyde directly causes epigenetic changes.
The research team is now exploring biomarkers indicating high formaldehyde levels in the body that could signal an increased risk of cancer. They are also investigating whether increased levels of formaldehyde in the body contribute to aging.
Formaldehyde’s Evolutionary Role
Chang argues that formaldehyde’s role in life dates back to early evolutionary history, as it is known to affect growth in simpler organisms like bacteria. The implications of this discovery are far-reaching and raise new questions about the importance of one-carbon metabolism in the evolution of life.