Investigating Mechanisms of Recurrence after Immune Gene Therapy in G34-Mutant Pediatric High-Grade Glioma
Award: $750,000 over 2 years (awarded 2024)
Principal Investigator: Dr. Maria Castro, University of Michigan
Funding Partners: Pediatric Cancer Foundation
Pediatric high-grade gliomas remain among the most devastating childhood cancers, and those driven by the H3.3-G34 mutation are especially aggressive. Even when children respond to treatment, these tumors almost always come back and when they recur, survival is measured in months. Understanding why these tumors return, even after promising therapies, is one of the most urgent challenges in pediatric neuro-oncology.
This project tackles that challenge head-on by developing two powerful, first-of-their-kind systems that allow researchers to watch, at single-cell resolution, how tumors respond to therapy, how resistance emerges, and which specific cells are responsible for recurrence.
The team first built a highly faithful preclinical model of H3.3-G34–mutant glioma and tested an immune-stimulating gene therapy designed to both kill tumor cells and activate the child’s immune system. This showed that some tumors disappeared completely, others never responded, and some shrank only to grow back. This diversity mirrors what happens in children and creates an unprecedented opportunity to study the biology of success, failure, and relapse. In parallel, the researchers created a sophisticated genetic barcoding system, giving every tumor cell its own permanent “ID card.” This allows scientists to track which exact cells survive therapy, which ones expand afterward, and which rare clones drive recurrence. Together, these tools make it possible for the first time to pinpoint the specific tumor and immune-cell programs that determine whether a child responds to therapy or not. The approach bridges fundamental biology and translational research, opening the door to targeted strategies that eliminate resistant clones before they return.
This work represents a major step toward answering one of the most heartbreaking questions families face: Why did the tumor come back?
By uncovering the mechanisms of recurrence, this project is laying the scientific foundation for therapies that are not only effective initially, but truly durable—bringing hope for treatments that prevent relapse, reduce treatment-related toxicity, and dramatically improve outcomes for children with high-grade glioma.
