Asbestos and Cancer

Over 20 million people in the U.S., and many more worldwide, who have been exposed to asbestos are at risk of developing mesothelioma, a malignant cancer of the membranes covering the lungs and abdomen that is resistant to current therapies. On the other hand, exposure to asbestos increases the risk of lung cancer among smokers. Over the past 40 years researchers have tried to understand what causes cancer of asbestos.

The answer appears in a study published in the current issue of the Proceedings of the National Academy of Sciences, USA, Drs. Haining Yang and Michele Carbone at the University of Hawaii Cancer Research Center led a research team that included colleagues at the University of New York, the University of Chicago, University of Pittsburgh, San Raffaele University of Milan, and the Imperial College in London.

These researchers focused on the paradox of how the asbestos fibers that kill cancer cells can cause as a dead cell should not be able to grow and form a tumor. They found that when asbestos kills cells, it does so by inducing a process called programmed cell necrosis, which leads to the release of a molecule called high mobility group box 1 protein (HMGB1). The HMGB1 initiates a particular type of inflammatory reaction that causes the release of mutagens and the factors that promote tumor growth. The researchers found that patients exposed to asbestos have elevated levels of HMGB1 in serum. So, say it is possible to target the HMGB1 to prevent or treat mesothelioma and determine the cohorts exposed to asbestos by simple serological test for HMGB1.
In the article, the researchers propose that by interfering with the inflammatory reaction caused by asbestos and HMGB1 may be possible to reduce the incidence of cancer among generations exposed to asbestos and decrease the rate of tumor growth among those already affected by mesothelioma. Drs. Yang and Carbone, the lead authors, state that to test this hypothesis, they are now planning a clinical trial in a remote area in Cappadocia, Turkey, where over 50% of the population dies of malignant mesothelioma. If results are positive, the approach will be extended to the cohorts of people exposed to asbestos in the U.S..

This research highlights the role of inflammation in the cause of the different types of cancer and provide new clinical tools to identify exposed individuals and prevent or reduce tumor growth. Researchers wonder whether we can prevent this cancer, like colon cancer, by a simple aspirin or similar drugs that stop inflammation. They’re about to test this hypothesis.