Releasing the Brakes on the Body’s Response to Melanoma
Education & Research Cancer immunotherapy, the science of using the body’s own immune system to fight cancer, is an exciting new avenue in cancer treatment that is starting to show significant success.
Identifying the problem
The immune system, which recognizes and removes infectious material like bacteria, can also attack and kill cancer cells. First, however, the immune system has to recognize cancer cells as something it should destroy. To escape immune attack, cancer takes advantage of the body’s natural built-in mechanisms, called checkpoints, which act like brakes on a car to stop the immune system from overreacting.
The challenge is to release the brakes so the immune system can do its work and go after the cancer cells. We’ve been investigating antibody drugs that inhibit the checkpoints.
Clinical trials are being run to test and refine this approach. Currently, clinical trials are testing and combining checkpoint inhibitor drugs in 10 or more human cancers with very promising results so far.
"The hope is that this effort to personalize treatment patient by patient will increase survival and benefit those suffering from this terrible disease."
Also being developed are approaches that boost the activity of immune cells called T lymphocytes, the ones that attack foreign cells. Under normal biological conditions, only limited numbers of T lymphocytes are activated. In the adoptive cell transfer approach, we take T lymphocytes from the patient, isolate those that are naturally cancer-specific or modify those that are not to enable them to recognize the cancer cells, and multiply them in the laboratory into large numbers. Then these T cells are transfused back into the patient, where they can attack the cancer. It’s like recruiting a few soldiers and turning them into a vast army.
Both of these approaches have shown very encouraging results in clinical trials. We are continuing to work on ways to tell which patients will respond, and how to combine these approaches to give the patients’ own immune systems the best ammunition to fight their disease.
Even with the encouraging progress in immunotherapy, the majority of patients with advanced metastatic melanoma still find themselves out of treatment options. Patients are often sought out to participate in a different kind of clinical trial that investigates ways to individualize treatment for metastatic melanoma so that patients receive the drugs that are most likely to work. The hope is that this effort to personalize treatment patient by patient will increase survival and benefit those suffering from this terrible disease.