Scientists at Mass General Brigham and Dana‑Farber Cancer Institute discovered that a single shot of a specially‑designed virus can pull immune cells deep into brain tumors and keep them working there. The study, published in Cell, shows that this method helped patients with glioblastoma—an aggressive type of brain cancer—live longer during a recent trial.
Engineered Herpes Virus Targets Cancer Cells
The treatment uses an oncolytic virus created by Dr. E. Antonio Chiocca. It is a modified herpes simplex virus that can only copy itself inside glioblastoma cells, leaving healthy brain tissue untouched.
When the virus gets inside a cancer cell, it breaks the cell apart and then makes many copies of itself. Those copies travel to neighboring tumor cells, destroying them too. This not only kills cancer directly but also wakes up the immune system. In a Phase 1 trial with 41 patients who had tumors come back, the virus gave them a longer life span than usual, especially for those who already had antibodies against the virus.
Immune Response Linked to Longer Survival
To see how the therapy works, researchers examined tumor pieces from the trial participants. They found that immune‑fighting T cells stayed inside the tumors for a long time. Patients whose T cells were close to dying tumor cells tended to survive longer.
The virus also increased the number of existing T cells already in the brain, suggesting it strengthens the body’s own defenses instead of relying only on new immune activity.