UCLA researchers have developed a new combination immunotherapy to treat advanced brain cancer.
The combination treatment works by preventing brain cancer cells from shielding themselves from a patient’s own immune responses.
The three-year study, published Thursday, found that antibody blocking of an immune cell’s PD-1 surface receptors combined with a dendritic cell vaccine is more effective than using either one alone. Previous studies have shown these surface receptors to suppress normal immune response while dendritic cell vaccinations induce normal immune response, through intracranial immune cell activation.
Robert M. Prins, leader of the cancer research and member of the UCLA Jonsson Comprehensive Cancer Center, said he and his team discovered that effective immunity to glioblastoma requires a robust killer T cell response in order to attenuate immune cells within the tumor.
Although PD-1 antibody blockade removes the shield that glioblastomas activate to hide from a patient’s immune system, it may not be successful by itself in tumors that do not have sufficient infiltration of killer T cells, a type of white blood cell that lyses cancer cells. The dendritic cell vaccination allows necessary infiltration of these killer T cells into the tumors. Thus, the two combined treatment of both vaccine and antibody blockade allow for a more effective immunotherapy.
Glioblastoma constitutes about 15.4 percent of all primary brain tumors, according to the American Brain Tumor Association. Most people who are diagnosed face a median survival rate of 14.6 months.
The research findings are the first to outline how an effective immune response can be activated in the advanced brain cancer, said Prins.
Prins and Linda Liau, another leader of the research team, have filed to obtain a patent on the glioblastoma vaccine combination treatment.