Genetic Components of Malignant Mesothelioma

Malignant mesothelioma is an uncommon but particularly aggressive type of cancer that can often be fatal if not detected early on in its development. Mesothelioma patients are typically people who were exposed to asbestos-containing materials (such as vinyl tiling or old-fashioned insulation material) over a long period of time. Many people diagnosed with mesothelioma today worked long ago in industries which caused them to breathe in or swallow asbestos fibers day in and day out. Mesothelioma often remains dormant for some time after asbestos exposure, and thus, many of its victims are retired from the occupations which caused them to be exposed to the asbestos that caused their cancer in the first place.

Can Genetics Cause Mesothelioma?

Although genetics are not the direct cause of malignant mesothelioma, there are certain genetic factors that have some influence on which individuals who are exposed to carcinogens will develop cancer after that exposure. It appears that some people are more vulnerable to developing mesothelioma after exposure to asbestos or erionite fibers than others, and genetics may be the underlying reason why.

Are Some People Genetically Predisposed to get Diagnosed with Mesothelioma?

Mesothelioma is not caused by any specific gene. However, recent research into populations of people where mesothelioma is prevalent—be it geographic or within a given family—have shown that some people may be more genetically apt to develop mesothelioma and other types of cancer than others.

What other Genetic Factors Influence the Development of Mesothelioma?

Within the past few years, research has been conducted to study the genetic factors that may influence the development of mesothelioma cancer—after all, only a fraction of people exposed to asbestos and other carcinogens over the long term actually end up with a mesothelioma diagnosis. The reason for this could lie within the genetic code. Researchers have found that in individuals with mesothelioma, certain tumor-suppressing genes appear to be mutated (versus individuals who have been exposed to carcinogens but have not developed mesothelioma).

Tumor Suppressor Genes: an in-depth Look

Tumor suppressor genes are exactly what they sound like: bits of genetic coding whose purpose is to suppress the growth and spread of malignant tumors, such as those that occur in mesothelioma. Recent research focusing on these genes and their expression in patients with mesothelioma suggests that the reason some people with mesothelioma risk factors do not end up developing the cancer (while others experiencing the same occupational or environmental conditions do) may be due to mutations in tumor suppressor genes. Let’s explore a few of these genes below:

BAP1 gene

BRCA-associated protein 1 (BAP1) is the name of a tumor suppressor gene that is mutated in many individuals who have malignant mesothelioma. According to recent research conducted by scientists in Japan, in patients with mesothelioma, the BAP1 gene is often inactivated, leading to improper modification of histones in the body, which may facilitate the growth and spread of mesothelioma and other cancers. In people whose families show a history of mesothelioma, BAP1 is thought to be partially responsible.

NF2 Gene

Another tumor suppressor gene that has been linked to mesothelioma development is neurofibromatosis type 2 (NF2). This gene, when functioning properly, aids in regulating the proliferation of cancer cells. However, when the gene becomes mutated, it is unable to perform its main function, which allows for malignant tumors to grow and spread unchecked. More than a third of patients with malignant mesothelioma show a mutation in the NF2 gene.

LATS2 Gene

Large tumor suppressor homolog 2 (LATS2) is another gene which has recently been shown to often be mutated in mesothelioma patients. This gene serves an inhibitory function with regard to cancer cell growth, and is often altered or even deleted in people who have malignant mesothelioma. LATS2 is associated with something called the Hippo pathway, a pathway by which our internal organs are generated while still in utero. This same pathway appears to be used in the generation of tumor cells in mesothelioma patients.

Implications for the Future

If genetic mutations that give rise to mesothelioma spread and growth could be controlled by genetic manipulation or other treatments that target the mutated or deleted genes in question, more effective and less debilitating treatments for malignant mesothelioma could come into being. More research on the role of tumor suppressor genes is needed at this time and is currently underway, with the hope that less invasive, more directly-targeting mesothelioma treatments may be just over the horizon.