It is a proven fact that asbestos exposure can develop into deadly mesothelioma. But how does this happen to healthy cells? Microscopic asbestos fibers are inhaled into the lungs, yet the deadly mesothelioma disease can appear in physically remote mesothelial cells¹.
Arti Shukla, Ph.D., associate professor of pathology and laboratory medicine at the University of Vermont’s Larner College of Medicine and a UVM Cancer Center member, along with colleagues, used two groups of cells – lung epithelial cells¹ and macrophages¹ – in their study because these two cell groups are the first that asbestos fibers encounter when inhaled. These cells were divided into two groups: one exposed to asbestos fibers and the other left alone to grow normally. They grew for three days.
At that time, they collected the exosomes² released by the cells. By examining the proteins in the exosomes, they found the group exposed to asbestos had a great deal of suspicious proteins as opposed to the non-exposed group. The exosomes containing the suspicious proteins were then added to healthy mesothelial cells. After four days, they found significant changes to many cancer-related genes in the previously healthy mesothelial cells.
Why is this important?
This study suggests that exosomes, with their ability for intercellular communication, can alter cellular genetics – even from a distance. It also indicates these exosomes and their proteins, can act as biomarkers pointing to the development, or even the progression, of asbestos-related disease.
Shukla states, “Our findings suggest that cells in one region of the body are capable of sending messages to cells in a distant location, and can cause significant genetic changes. This communication from injured or diseased cells to healthy cells has the potential to initiate changes that might lead to cancer or other diseases.”
Editor-in-chief of The FASEB Journal, Thoru Pederson, Ph.D., adds, “These intriguing findings go a good ways toward explaining the conundrum of how a pulmonary irritant triggers distant effects. They also add to the burgeoning array of studies that link exosome-based communication to pathogenic events.”
In summary, this is an important step toward treating – and perhaps one day curing – mesothelioma.
Vocabulary of the disease
¹Cell types involved:
Mesothelial cells: These cells form a slippery, non-adhesive protective layer, the mesothelium, in the body’s serous cavities and internal organs.
Epithelial cells: These are the body’s safety shield. Your skin is comprised of millions of these cells, but they also line all your organs, intestines, blood vessels, and throat.
Macrophages: This is a type of white blood cell, carried by your blood to the site of infections. When epithelial cells are damaged, they release chemicals to attract macrophages. They can clean up harmful bacteria, viruses, and dead cells.
²Exosomes: These are very small vesicles that carry RNA and proteins. They were once thought of as merely garbage cans for cell debris, but now are the focus a great deal of scientific interest. Researchers found they enable intercellular communication that may lead to minimally invasive diagnostics.