The MCA BlogConnecting with others one story at a time
Each day, doctors and research and health organizations are working to better understand the development process of cancer. By understanding how a disease develops, doctors and researchers can create more targeted treatment protocols for patients.
Normal cells behave themselves—when cells are damaged, they grow into the adjacent spaces and then stop. However, the first inklings of transformation into cancer starts with damage to a cell. Cells can sense when their DNA has been damaged using the p53 gene. The p53 gene can determine the damage in the cell and start a cascade of enzymes and messengers to bring the necessary building blocks and enzymes (like carpenters, electricians, plumbers, project managers) to fix the cell’s damage.
Cells accumulate damage over the years. For mesothelioma patients, cancer is developed after exposure to several types of asbestos. Asbestos crystals act like needles and can physically damage the cells. Asbestos can also trigger stress in various cell organelles. Chronic exposure to asbestos damages the cells and promotes inflammation.
Alternatively, the p53 gene may decide that the damage in the cell cannot be repaired and it triggers cell suicide, which is called programmed cell death or apoptosis.
Chronic Asbestos Exposure and Cell Mutations
In mesothelioma, the function of the p53 gene is usually blocked because one of its main messengers, p14 (ARF) is deleted. Several agents that reactivate the function of p53, which would allow damaged cells to be repaired or killed, are being tested in mesothelioma cell lines in tissue culture:1 they show promise,1 but it will be a while before they begin testing in clinical trials.
The neurofibromatosis gene encodes a protein named merlin and is sometimes mutated in mesothelioma. Merlin is a tumor suppressor gene that can interact with the structure of the cells and helps them keep their shape, helps the cell move, helps cells talk to each other, and helps control how fast cells grow. With all of the positive qualities of merlin that aid in cell repair, it is clear why a mutation of merlin could be detrimental to one’s health.
The controls of genes can be damaged also: turning off genes (or silencing them) occurs by methylation, like adding work in progress signs on genes. For example, another important tumor suppressor known as microRNA--34b/c (a small RNA that affects the expression of other genes) is often turned off in mesothelioma.2 When researchers added back the microRNA-34b/c to mesothelioma cells, they stopped growing, migrating, and stayed put.2
Mesothelioma is a relatively preventable disease; avoid the risk of mesothelioma by reducing exposure to asbestos. This can be done by moving from an area with high exposure risk or taking the proper precautionary steps when encountering an area with asbestos.
Maintaining a Healthy Immune System
When even healthy people’s peripheral blood cells are transferred into a special kind of mouse, SCID, which doesn’t have an immune system, lymphomas will arise on a very predictable schedule, within 6-7 weeks or 10-12 weeks.3 However, most people do not get lymphoma. Instead, their immune systems keep killing any cancerous cells that arise in the blood so they don’t get a chance to grow.
Thus, keeping your immune system healthy may help remove damaged cells, and remove waste, and patrol for abnormal precancerous cells.
1. Di Marzo D, Forte IM, Indovina P et al. Pharmacological targeting of p53 through RITA is an effective antitumoral strategy for malignant pleural mesothelioma. Cell Cycle 2014;13(4):652-665.
2. Kubo T, Toyooka S, Tsukuda K et al. Epigenetic silencing of microRNA-34b/c plays an important role in the pathogenesis of malignant pleural mesothelioma. Clin Cancer Res 2011;17(15):4965-4974.
3. Picchio GR, Kobayashi R, Kirven M, Baird SM, Kipps TJ, Mosier DE. Heterogeneity among Epstein-Barr virus-seropositive donors in the generation of immunoblastic B-cell lymphomas in SCID mice receiving human peripheral blood leukocyte grafts. Cancer Res 1992;52(9):2468-2477.
Resources for Mesothelioma Patients and their Families
- Request a Free Mesothelioma Treatment Guide
- Connect with Top Mesothelioma Doctors
- Locate the Nearest Comprehensive Cancer Center