Mesothelioma is a rare and aggressive form of cancer that affects the lining of the lungs, abdomen, and heart. It is primarily caused by exposure to asbestos fibers, and the disease can take decades to manifest. Mesothelioma is challenging to treat, and conventional therapies such as chemotherapy, surgery, and radiation have limited success in extending the patient’s lifespan. However, immunotherapy has emerged as a promising treatment option for mesothelioma patients, offering hope for improved outcomes and quality of life.
Immunotherapy is a type of cancer treatment that uses the body’s immune system to fight cancer cells. It works by boosting or restoring the immune system’s ability to recognize and destroy cancer cells. There are several types of immunotherapy, including checkpoint inhibitors, monoclonal antibodies, cancer vaccines, and adoptive cell transfer.
Checkpoint inhibitors are a type of immunotherapy that targets proteins on the surface of T cells, which are immune cells that recognize and attack cancer cells. Cancer cells can sometimes evade T cell attacks by producing proteins that bind to T cell proteins and turn off their function. Checkpoint inhibitors block these proteins, allowing T cells to attack cancer cells more effectively. Pembrolizumab (Keytruda) and nivolumab (Opdivo) are two checkpoint inhibitors that have been approved by the FDA for the treatment of mesothelioma.
Monoclonal antibodies are another type of immunotherapy that works by targeting specific proteins on cancer cells. These antibodies can either block the proteins’ function, causing the cancer cells to die, or they can attach to the proteins, making them more visible to the immune system. Bevacizumab (Avastin) is a monoclonal antibody that has been approved by the FDA for the treatment of mesothelioma.
Cancer vaccines are a type of immunotherapy that aims to stimulate the immune system to recognize and attack cancer cells. These vaccines can be made from cancer cells, proteins, or DNA, and they work by presenting cancer cells as foreign to the immune system, triggering an immune response. There are currently no FDA-approved cancer vaccines for mesothelioma, but several clinical trials are underway to test their effectiveness.
Adoptive cell transfer is a type of immunotherapy that involves removing immune cells from a patient, modifying them in a lab to recognize and attack cancer cells, and then reintroducing them into the patient’s body. This approach has shown promise in clinical trials for other types of cancer, but it is still in the early stages of development for mesothelioma.
The role of immunotherapy in treating mesothelioma is still being studied, but early results have been promising. Checkpoint inhibitors, in particular, have shown significant activity in clinical trials, with response rates ranging from 10% to 29%. These responses have been durable, with some patients experiencing long-term remissions. However, not all patients respond to immunotherapy, and identifying those who are most likely to benefit remains a challenge.
One factor that may influence the effectiveness of immunotherapy in mesothelioma is the tumor’s mutational burden. Tumors with a high mutational burden are more likely to produce neoantigens, which are proteins that are unique to the tumor and can be recognized by the immune system. Studies have shown that patients with mesothelioma who have a high mutational burden are more likely to respond to immunotherapy.
Another factor that may influence the effectiveness of immunotherapy in mesothelioma is the presence of other immune cells within the tumor microenvironment. Some tumors are more resistant to immunotherapy because they are infiltrated with immune cells that suppress the immune response. Understanding the immune landscape of mesothelioma tumors may help identify patients who are most likely to respond to immunotherapy.
In conclusion, immunotherapy has emerged as a promising treatment option for mesothelioma patients, offering hope for improved outcomes and quality of life. While not all patients respond to immunotherapy, those who do may experience durable responses, and ongoing research is aimed at identifying biomarkers that can predict response. As our understanding of the immune system and cancer continues to evolve, so too will our ability to harness the immune system’s power to fight cancer.