How Air Pollution Quietly Rewrites Lung Cancer Genes

Secondhand smoke appears less mutagenic than air pollution, suggesting lower potential for causing genetic mutations.

Researchers from the National Institutes of Health (NIH), in collaboration with the University of California, San Diego, have discovered a strong link between fine particulate air pollution—commonly emitted by vehicles and industrial sources—and increased genetic alterations in lung cancer tumors among people who have never smoked ().

The team conducted the largest whole-genome analysis to date of lung cancer cases in never-smokers, revealing that prolonged exposure to polluted air is associated with a higher number of cancer-driving and cancer-promoting mutations.

Air Pollution
Nearly 2.4 million deaths every year are attributable to air pollution. Air pollutants may be solid particles, liquid droplets or gases. Proper planning methods should be adopted to reduce air pollution.

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#Air_pollution exposure is associated with TP53 gene changes and other mutational signatures previously linked to #tobacco #smoking. #LungCancer

New Paths to Combat Lung Cancer in a Growing Population

These findings not only provide critical insights into how environmental factors contribute to lung cancer in non-smokers but also open the door to new strategies for prevention and early detection in this growing patient population.

Researchers analyzed lung tumors from 871 never-smoker patients across 28 geographic locations worldwide as part of the Sherlock-Lung study.

Air Pollution Linked to Premature Telomere Shortening

They also observed a relationship between air pollution and shorter telomeres, which are sections of DNA found at the end of chromosomes. Telomeres shorten naturally with age and shorter telomeres are related to cells inability to continue to replicate. However, scientists found fine particulate air pollution was linked to premature shortening of telomeres.

Effects of Air Pollution on Health
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Prior genomic studies of lung cancer have focused on tobacco smokers, leaving a significant gap in our understanding of how lung cancer develops in people who have never used tobacco.

By beginning to uncover the mechanisms through which tissues acquire cancer-causing or cancer-promoting mutations following environmental exposures, this study helps scientists better understand the primary drivers of lung cancer in this population—which represents up to 25% of all lung cancer cases globally.

Lung Cancer
Lung cancer is a malignant tumor in the lung tissues. Smoking is the main cause of lung cancer with symptoms like recurrent respiratory diseases.

Interestingly, the researchers found that while exposure to secondhand smoke was associated with slightly higher mutation burdens and shorter telomeres, compared to tumors in patients who were not exposed, it did not lead to an increase in cancer-driving mutations or mutational signatures.

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