Malignant pleural mesothelioma or MPM is a rare but aggressive disease. There are no effective therapeutic options for this understudied cancer which is associated with exposure to carcinogenic mineral fibers, collectively known as asbestos.
A new study by scientists from the International Agency for Research on Cancer (IARC) and partners, published in the journal EBioMedicine, identified three sets of tumors with characteristic molecular features.
The identified molecular profiles have the potential to guide the clinical management and treatment strategies for malignant pleural mesothelioma and improve the general understanding of the carcinogenic processes that contribute to this lethal disease.
Today, most patients with malignant pleural mesothelioma die within 2 years after diagnosis. The primary reason is that there only a limited number of available therapeutic options and early detection opportunities.
Another reasons is that, in contrast of other, more common forms of cancer, there are only a few molecular studies being conducted in helping gain a better understanding of malignant pleural mesothelioma.
A public health problem
Although the use of asbestos has been banned in many developed countries, malignant pleural mesothelioma is still a public health problem. The long latency of the disease, often several decades, together with the ageing of the population, the increased environmental exposure, and the continuing use of asbestos, mostly in developing countries, are among key factors involved.
However, in contrast to popular understanding, while the use of asbestos is banned in most industrialized countries, including, Australia, Canada and all 28 countries of the European Union, the use of asbestos is still legal in the United States, where it continues to be used in gaskets, friction products, roofing materials, fireproofing materials and other products that are used every day.
In addition, the United States continues to import and use asbestos and there are no plan for stricter regulations in place. According to the U.S. Geological Survey, the United States imported 750 metric tons of asbestos in 2018.
In combination the ‘legacy’ products containing asbestos, the ongoing use of the ‘miracle mineral’ adds, according to the American Journal of Epidemiology, to the more than 2,000 expected cases of mesothelioma in the United States each year as well as the diagnosis of 2,000 to 3,000 other asbestos related tumors.
“Innovative sequencing technologies that provide information on the molecular characteristics of tumors can now uncover differences among tumors that look quite similar under the microscope,” said Matthieu Foll, Ph.D, a scientist in the Genetic Cancer Susceptibility Group at the International Agency for Research on Cancer (IARC), an agency of the World Health Organization (WHO), and a lead author of the study.
“The expression of proteins associated with the immune and vascular systems in the tumors enabled us to identify molecular profiles that may explain the differences in overall survival and response to treatment,” Foll added.
Scientists at the IARC worked in close collaboration with the French teams managing the MESOPATH/MESOBANK database, a multicentre exhaustive repository of national clinical data, biological samples, and standardized operational procedures for malignant mesothelioma.
“We have been able to confirm our results and identify a panel of five proteins that is sufficient to characterize these molecular profiles of malignant pleural mesothelioma and that could be used in the clinic to assist the diagnosis and inform clinical management,” concluded Lynnette Fernandez-Cuesta, Ph.D, an IARC scientist and co-lead author of the study.
 Alcala N, Mangiante L, Le-Stang N, Gustafson CE, Boyault S, Damiola F, et al. (2019). Redefining malignant pleural mesothelioma types as a continuum uncovers immune-vascular interactions. EBioMedicine. Published online 21October 2019; https://doi.org/10.1016/j.ebiom.2019.09.003