Smoking and Asbestos
Several studies have independently looked at the risks of smoking and asbestos exposure with regard to the development of lung cancer. Smoking is the most significant factor contributing to 80-90% of lung cancer cases, with asbestos contributing to up to 8% of all lung cancers. Although each of these factors can contribute independently to lung cancer, some cancer cases may be the result of combined asbestos exposure and smoking and the combined carcinogenic effects can be especially detrimental.
Both asbestos exposure and smoking increase the rate of mutations in tumor suppressor genes such as p53. Mutations and altered function of this tumor suppressor gene commonly lead to cancer by contributing to the dysregulation of this gene through different mechanisms. Asbestos exposure leads to non-specific mutations in p53 while smoking leads to other very characteristic and well-defined mutations. Particularly since each of these environmental carcinogens impact tumor suppressors differently, the risk of developing cancer is compounded when both of these factors are involved.
Combined asbestos exposure and smoking also dramatically increases loss of heterozygosity, meaning that each of these risk factors cause regions of DNA to be lost entirely. Similar to mutations altering the way genes work, the loss of all of part of a gene will also result in improper function or a loss of function. When this dysfunction affects a tumor suppressor gene, there is a very high risk of cancer. The mutations resulting from asbestos exposure and smoking in addition to the loss of genetic material results in a compounding effect for people exposed to asbestos who are also smokers.
It is important to be aware that, although the majority of lung cancer is related to smoking, lung cancer in smokers may still be attributable to asbestos exposure. Regardless of whether you are a smoker, if you have been exposed to asbestos and develop lung cancer, asbestos exposure may still be a factor in your cancer development and progression.
If you have developed lung cancer following asbestos exposure, contact us.
- O’Reilly KM, Mclaughlin AM, Beckett WS, Sime PJ. Asbestos-related lung disease. Am Fam Physician. 2007; 75(5):683-8.
- Inamura K, Ninomiya H, Nomura K, Tsuchiya E, Satoh Y, Okumura S, Nakagawa K, Takata A, Kohyama N5, Ishikawa Y. Combined effects of asbestos and cigarette smoke on the development of lung adenocarcinoma: Different carcinogens may cause different genomic changes. Oncol Rep. 2014; 32(2):475-82.