Cigarette smoking is a well-established risk factor for cancer, but the molecular mechanisms by which smoking leads to cancer have not been fully understood.
Researchers at the Ontario Institute for Cancer Research (OICR) have conducted a study shedding light on one of the ways tobacco smoking promotes cancer development and complicates its treatment.
Stop-Gain Mutations and Cancer: Published in Science Advances, the study reveals that tobacco smoking is associated with specific DNA alterations known as ‘stop-gain mutations.’
These mutations instruct the body to halt the production of certain proteins prematurely, before they are fully functional.
Notably, these mutations tend to affect genes referred to as ‘tumor-suppressors,’ which typically produce proteins that prevent abnormal cell growth.
Disrupting Tumor-Suppressors: The researchers found that smoking-induced stop-gain mutations disrupt the formation of tumor-suppressor proteins.
Consequently, abnormal cells can proliferate unchecked, weakening the body’s defenses against cancer and facilitating its development.
Analyzing Thousands of Tumor Samples: To arrive at their findings, the research team employed advanced computational tools to analyze DNA from over 12,000 tumor samples across 18 different cancer types.
Their investigation revealed a strong connection between stop-gain mutations in lung cancer and the distinct genetic alterations left behind by smoking.
The Impact of Smoking Intensity: Further analysis showed that the extent of smoking correlated with the prevalence of these harmful mutations.
In essence, individuals who smoked more exhibited a higher frequency of these mutations, ultimately making cancer more intricate and challenging to treat.
The DNA Damage by Smoking: Dr. Jüri Reimand, an OICR Investigator and Associate Professor at the University of Toronto, emphasized that tobacco smoking inflicts substantial DNA damage on cells.
This damage hinders the function of essential proteins, impairing the building blocks of cells and impacting long-term health.
Additional Factors Contributing to Mutations: The study also identified other factors and processes responsible for generating stop-gain mutations, also known as ‘nonsense’ mutations.
While some factors, like the APOBEC enzymes linked to breast cancer, occur naturally in the body, others, such as an unhealthy diet and alcohol consumption, may have similar detrimental effects on DNA. However, further research is needed to fully comprehend these mechanisms.
The Importance of Understanding Smoking’s Mechanisms: Nina Adler, the lead researcher, stressed the significance of this study in elucidating one of the molecular pathways through which smoking increases cancer risk. It underscores the crucial role of lifestyle choices in cancer development.
A Warning Against Smoking: Dr. Laszlo Radvanyi, OICR President, and Scientific Director, emphasized that these findings underscore the immense harm inflicted by smoking on the body.
He urged the public to recognize smoking as a grave threat to health and reiterated that quitting smoking is always the right choice.
Conclusion: The study offers valuable insights into how smoking contributes to cancer by disrupting DNA and impairing the body’s defense mechanisms.
Understanding these mechanisms reinforces the importance of adopting a smoke-free lifestyle to reduce the risk of cancer.
If you care about smoking, please read studies about why some non-smokers get lung disease and some heavy smokers do not, and smoking cessation drug may help treat Parkinson’s disease.
For more information about heart health, please see recent studies about new way to prevent heart attacks and strokes, and results showing this drug for heart disease may reduce COVID-19 risk.
The research findings can be found in Science Advances.
Follow us on Twitter for more articles about this topic.
Copyright © 2023 Knowridge Science Report. All rights reserved.
