For people diagnosed with glioblastoma, one of the most aggressive brain cancers, treatment options have long been limited and outcomes grim. But researchers at McMaster University in Hamilton, Canada, are offering new reason for hope. A team of scientists has developed an immunotherapy strategy that doesn't just attack the tumor—it also dismantles the cellular support system that helps the cancer survive and grow.
The research, published in the journal Nature, focuses on a protein called GPNMB that appears on both glioblastoma cells and the immune cells called macrophages that tumors hijack to protect themselves. Normally, macrophages help fight infection, but glioblastoma can reroute them to feed the tumor, block other immune attacks, and resist treatment.
"Instead of treating the tumor as only a mass of cancer cells, we suggest that we must treat glioblastoma as a connected tumor-immune ecosystem," said Sheila Singh, a professor of surgery at McMaster who co-led the study. "Our approach attacks both the tumor and the environment that allows it to thrive."
The team used CAR-T cell therapy, a type of treatment that reprograms a patient's own immune cells to recognize and destroy cancer. In several preclinical tests—including models grown from actual patient tumors—the therapy eliminated detectable tumors and led to long-term disease-free survival. The researchers say this is the first strategy to target both the cancer and its immune accomplices simultaneously.
The work builds on earlier research, including a first-in-human clinical trial for patients with metastatic sarcoma led by the University of Calgary. That trial, detailed simultaneously in Nature Cancer, found GPNMB to be a promising target across multiple cancer types.
"CAR-T therapy has been effective in some blood cancers, but translating that success to brain tumors has been difficult," said Shan Grewal, an MD/PhD candidate at McMaster and co-lead author. "Most approaches have focused on killing cancer cells alone. Our work suggests we may also need to dismantle the immune support system that helps the tumor survive."
The McMaster team worked with collaborators from King's College London, Northwestern University, the University of Calgary, the University of Toronto, and The Hospital for Sick Children. While the results are promising, researchers caution that more work is needed before the treatment can move into clinical trials for human patients. Still, for families facing this devastating diagnosis, the approach represents a meaningful shift in how scientists think about fighting brain cancer—one that targets the enemy's entire army, not just the visible soldiers.