Scientists have discovered that a protein called osteopontin is found in higher levels in mesothelioma tumors than in normal tissues.
Mesothelioma is a type of cancer that affects the lining of some organs in the body. It is caused by exposure to tiny fibers called asbestos. When these fibers are breathed in, they can get stuck in the lining of the lungs, heart, or abdomen. Over time, they can cause cancerous cells to grow there.
Mesothelioma is also very rare. This means that doctors and scientists are still learning about how this cancer grows and the best ways to treat it. The current treatments for mesothelioma include surgery, chemotherapy, and radiation. These treatments are not always effective, so scientists are looking for better ways to improve survival outcomes.
A Potential Target for Slowing Mesothelioma Tumor Growth
The scientists in this study looked at tissue samples from mesothelioma patients to see what kind of substances they could find in the tumors. They were interested in substances that caused inflammation.
The scientists found that osteopontin was found at high levels in the tumor tissue samples. The protein was mainly produced by the cancer cells. The levels of osteopontin in the patients’ blood were also higher than in healthy patients and linked to a worse prognosis.
The scientists thought that treating mesothelioma patients with immunotherapy might make the osteopontin levels go down. Immunotherapy is a type of treatment that uses the patient’s immune system to treat mesothelioma.
Interestingly, patients who received immunotherapy did not have lower osteopontin levels. This finding led the scientists to run some tests in mice to find out why this happened.
They discovered that two different types of mesothelioma cells produced a lot of osteopontin. When they blocked the gene responsible for producing osteopontin, the tumors grew more slowly in the mice.
Based on these results, the scientists think that osteopontin is a substance that helps mesothelioma cells grow. Stopping osteopontin from being produced could be a way to slow down the growth of mesothelioma tumors.
Digifico E, Erreni M, Mannarino L, et al. Important functional role of the protein osteopontin in the progression of malignant pleural mesothelioma. Front Immunol. 2023;14:1116430. Published 2023 Jun 16. doi:10.3389/fimmu.2023.1116430. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10312076/