Research finding a link between air pollution and cancer will change the game, Scientists claim to have figured out how air pollution causes cancer, a finding that significantly advances our knowledge of tumor development.
Air pollution does not directly cause damage, but rather, as demonstrated by a study at London’s Francis Crick Institute, it alerts dormant, previously damaged cells.
Prof. Charles Swanton, one of the world’s foremost authorities, hailed the discovery as ushering in a “new age.”
In addition, medications that prevent the growth of cancer may now be within reach.
These results may shed light on the mechanisms through which hundreds of carcinogens cause cancer.
According to conventional cancer theory, it all begins with a normal cell. As it continues to accumulate mutations, its DNA eventually reaches a critical level. When that happens, it multiplies like cancer.
On the other hand, there are issues with this theory, such as the fact that malignant mutations can be found in apparently healthy tissue and that many agents known to cause cancer, such as air pollution, do not appear to alter people’s DNA.
Now, then, what’s going on here?
Researchers have uncovered data to support an alternative theory. The mutations and other DNA damage that come with age and development are already present in our cells; all that’s needed is a trigger to turn them malignant.
Research into the occurrence of lung cancer in those who do not smoke led to the discovery. While smoking is the primary cause of lung cancer, air pollution is now thought to be responsible for one in ten occurrences in the United Kingdom.
The researchers at Crick zeroed on a type of pollution whose particles are a thousand times smaller than the width of a human hair: particulate matter 2.5 (PM2.5).
Extensive trials with both humans and animals demonstrated:
More cases of nonsmoker lung cancer were seen in areas with increased air pollution.
Interleukin-1-beta is a chemical alarm that is activated in the lungs when PM2.5 is inhaled.
This leads to lung inflammation and the activation of repair cells.
However, in the lungs of a 50-year-old, approximately one in every 600,000 cells already harbors potentially malignant mutations.
These develop with age but fool everyone into thinking they’re healthy until the chemical alarm goes off and they transform into malignant cells.
Importantly, the researchers found that a medication that suppresses the warning signal prevented cancer from developing in mice exposed to air pollution.
The findings represent a major step forward for our knowledge of how air pollution affects human health and for our comprehension of the underlying causes of cancer.
Crick researcher Dr. Emilia Lim noted that many patients who had never smoked but nevertheless had lung cancer had no idea what had caused it.
She stressed the significance of providing “some clues about how this might work” to the audience.
To paraphrase one expert: “It’s super-important since 99% of people in the globe live in places where air pollution exceeds the WHO recommendations, so it really affects all of us.”
Understanding cancer in a new light
However, the data also demonstrated that mutations are not necessarily necessary to induce cancer. It may require something more.
This “really rethinks our concept of how cancers are initiated,” as Professor Swanton put it, is the most interesting finding his work has come across. He said it would usher in a “new age” in molecular cancer prevention.
If you happen to be a resident of a very polluted location, it may not be absolutely out of the question to consider taking a tablet to reduce your risk of developing cancer.
By mistake, doctors doing trials on interleukin-1 beta for cardiovascular illness discovered that the treatment also reduced the risk of developing lung cancer.
At a meeting of the European Society for Medical Oncology, researchers are hearing the most recent discoveries.
Prof. Swanton, speaking to the BBC from the conference, stated, “Pollution is a great example, but there are going to be 200 additional examples of this over the next 10 years.”
In addition, he said that our current understanding of how tobacco’s chemical constituents cause cancer must be revised. Does inflammation play a role in addition to the DNA damage that is already known to result from smoking?
Fascinatingly, in 1947, scientist Isaac Berenblum introduced the hypothesis that altered DNA alone is not enough to cause cancer to proliferate.
“Interesting from a philosophical standpoint. These brilliant biologists completed this study 75 years ago, and despite their efforts, it has been virtually forgotten “remarked Dr. Lim.
“Smoking remains the leading cause of lung cancer,” said Michelle Mitchell, CEO of Cancer Research UK.
Nonetheless, she continued: “Years of rigorous scientific research are shifting our understanding of cancer’s progression. Our knowledge of what causes lung cancer has greatly expanded.”