Air pollution linked to breast cancer

BY SOLA OGUNDIPE

Exposure to air pollution early in life or during childbirth may alter a woman’s DNA and make her more suceptible to developing premenopausal breast cancer later in life.

This is the latest discovery by researchers at the Social and Preventive Medicine Department of the University at Buffalo, USA.

Higher air pollution concentration at the time of first child birth also was associated with changes in p16, a gene involved in tumor suppression, according to findings.

Results of the research which were presented on April 6 at the 2011 American Association for Cancer Research meeting in Orlando, Florids, indicated that higher air pollution exposure at birth may alter DNA methylation, which may increase levels of E-cadherin – a protein important to the adhesion of cells, a function that plays an essential role in maintaining a stable cellular environment and assuring healthy tissues.

Methylation is a chemical process that has been implicated in determining which genes in a cell are active, a process essential to normal cellular function.

The bottom line is that women with breast cancer who lived areas with high air pollution were more likely to have the alteration in the DNA in their tumor than those who lived in a less-polluted region.

It is the first study to examine exposure to ambient air pollution at key points in a woman’s lifetime. The investigation looked for an association between exposure to pollution and alterations to DNA that influence the presence or absence of key proteins.

Such genetic changes are thought to be major contributors to cancer development and progression, including at very early stages. More research is needed to determine the role of air pollution in DNA methylation in breast cancer development and progression.