Immunotherapies are among the most promising techniques in oncology, but so far, they are largely unavailable to patients with brain cancer.
Many of these approaches are, however, being studied both in labs and in clinical trials, and the growing understanding of what works, what doesn’t and why provides a basis for hope that immunotherapy will eventually play a role in the treatment of gliomas.
Four researchers gave an overview of the state of that field during a Nov. 17 session at the 22ndAnnual Meeting and Education Day of the Society for Neuro-Oncology, in San Francisco.
Laying Out the Possibilities
The immunotherapeutic strategies being explored for the treatment of gliomas fall into four categories, explained Duane Mitchell, M.D., Ph.D., co-director of the Preston A. Wells Jr. Center for Brain Tumor Therapy and director of the University of Florida Brain Tumor Immunotherapy Program.
- Vaccines can boost the body’s ability to fight antigens, molecules that are perceived by the immune system as toxins or invaders. Studies have shown that this approach can safely generate immune responses.
- Adoptive cellular therapy can mean the use of tumor infiltrating lymphocytes (TILs) or chimeric antigen receptor (CAR) T cells. In these techniques, cancer-fighting T cells are removed from a patient, multiplied in a lab and then returned to the body. In CAR therapy, the T cells are engineered to hone in on the cancer before they are reinfused.
- Checkpoint inhibition uses medicine to block immune-suppressing proteins that are naturally made by the body. This frees up immune cells to fight harder against cancer.
- Oncolytic viruses, either natural or engineered, induce an immune response by invading and killing cancer cells while ignoring healthy cells.
All these techniques depend on scientists’ understanding of what drives a particular cancer and their ability to figure out which mutations, if silenced by medication, would lead to the slowing or eradication of the disease.