At the European Society of Medical Oncology (ESMO) Annual Conference, a team of researchers from the Vall d’Hebron Institute of Oncology in Barcelona found that a protein on the surface of mesothelioma cells corresponded strongly to how long a patient survived.

Specifically, patients whose mesothelioma cells produced a protein called PD-L1, or Programmed Cell Death Ligand 1, typically had a much more aggressive mesothelioma. Patients with higher levels of this protein had shorter survival times.

About 20 percent of patients with mesothelioma tested positive for PD-L1. In healthy humans, PD-L1 has the effect of turning down the immune system in cases when an overactive immune system can cause problems, like during pregnancy. However, PD-L1 appears to be part of the biochemical pathway that leads to many types of cancer when the protein misfires.

This information may sound like a disappointment for mesothelioma patients that test positive for PD-L1. However, the research represents a major step towards uncovering details about cancer in general, and mesothelioma in particular.

This could lead to next-generation mesothelioma treatments that could have improved survival rates, fewer side effects, and greater efficacy against mesothelioma. Many treatments for cancers focus on ways that cancer cells differ from healthy cells, and a greater understanding of a protein associated with cancer cells like PD-L1 could make it possible to more accurately target mesothelioma.

Mesothelioma is a cancer closely associated with asbestos exposure. Asbestos is a naturally-occurring mineral that was heavily mined and used since the Industrial Revolution. Asbestos fibers are extremely resistant to heat and fire, making them ideal for a host of applications, including fireproof insulation and working with high temperature applications in industry and science.

However, asbestos exposure is tightly linked to a variety of asbestos cancers, including mesothelioma. In fact, nearly all cases of mesothelioma can be attributed to asbestos exposure. Though the material was mostly phased out and banned in the United States by the 1980s, the material is still in older buildings.

Asbestos cancers like mesothelioma often take decades to fully manifest. In fact, asbestos litigation going on today still sometimes involves ship builders who worked in Navy shipyards during World War II. Asbestos cancers like mesothelioma will likely continue to be a medical issue for decades.