Mesothelioma is best known as the cancer associated with exposure to asbestos. A lesser known fact about mesothelioma is that the period between the exposure/s to asbestos and the development of the cancer (known as the ‘latency period’) is incredibly long, ranging on average between 20 and 50 years. While the bulk of mesothelioma science focuses on finding effective treatments against this aggressive cancer after the cancer has developed, some recent studies are also looking at the possibility to prevent or delay the onset of the cancer during the latency period.
Specifically, recent research out of the University of Hawaii is looking at an inflammation protein, HMGB1, as a biomarker for asbestos exposure and malignant mesothelioma, and at its reaction to acetylsalicylic acid (ACA), which is a metabolite of aspirin.
Researcher Haining Yang, MD, PhD, recently took some time to talk to us about these studies during a conference devoted to mesothelioma research. She explained that the role of the HMGB1 biomarker is twofold: its high presence can serve as an identifier of individuals without disease who may be at high-risk (and therefore possibly find themselves in the midst of the latency period or in the early stages of disease development), and also as a target for treatment once disease has begun to develop.
“What we found is that ACA, the metabolite of aspirin, can inhibit HMGB1, and we found that treating either the cell culture of the tumor, or mice carrying the tumor, can inhibit tumor growth,” said Dr. Yang.
Dr. Yang is quick to point out that this study is only a first step and that more work is necessary in determining whether these results also apply beyond cell lines and mice, and can be translated to humans. However, some unrelated preliminary evidence into the role of aspirin as cancer prevention already exists in other cancers like colon, breast, and liver and although a similar analysis for mesothelioma of the famous Physician’s Health Study was statistically inconclusive and cannot be officially reported, it provided researchers further reason to continue this work.
“Because mesothelioma is so rare, only 17 cases of mesothelioma were reported in the study. So while we did see a difference in numbers between the group taking aspirin and the group taking placebo, the numbers just aren’t high enough to draw a significant conclusion,” she said.
The numbers that she did see were consistent with those in colon cancer, which she points out makes sense because both cancers are related to inflammation.
So back to the question at hand: Can aspirin really serve as a preventative measure against mesothelioma?
The short answer is: Maybe. The long answer is: It’s complicated, but stay tuned for updates.