The following blog is an incredible update from Dr. Jensen, Director of the Ben Towne Center for Childhood Cancer Research, on what they are learning and working towards in regards to treating pediatric brain tumors. Read on…
T Cells on the Mind
We are garnering an increasingly sophisticated understanding of what reprogrammed T cells can do by studying over twenty-five children treated on our PLAT leukemia trials. To our surprise, these T cells, manufactured outside the body through genetic reprogramming, once infused in to the blood stream can grow prodigiously and hunt for leukemia throughout the body, including in the brain (a hiding place where leukemia can find safe haven from chemotherapy). By monitoring the cerebral spinal fluid (CSF), the watery liquid that surrounds our brain and spinal cord, we have found the CAR T cells in high numbers over long periods of time. This is great news for our leukemia patients– that T cells once administered in to the blood can fan out and find disease, even in the brain.
The implications of these findings, I believe, go well beyond the treatment of leukemia and provide support the rationale for taking reprogrammed T cell therapy to patients with brain tumors. Accordingly, the Velcro engineers at BTCCCR are busy assembling chimeric antigen receptors that bind to the common forms of brain cancer that afflict children—tumors having names such as medulloblastoma, ependymoma, brainstem glioma and the like. These tumors account for the most common group of solid tumors that arise in children, and lead the list of contributors to childhood cancer mortality. Because the brain is a difficult location to delivery standard chemotherapy drugs we still rely on radiation therapy in our attempts to help our young patients, with devastating consequences.
Developing reprogrammed T cells to go after brain tumors and metastasis of solid tumors that take root in the brain will require next generation technologies that are under development at BTCCCR. We have in the works on-off switches so T cells can be woken up to fight or allowed to rest should the brain need a respite. Also we are testing prototypes of growth genes for T cells that might be needed for their life support in the “outer space” of the central nervous system, where T cells have no natural home. Importantly, work is under way to coordinate the brain tumor attack using another fighter the monocyte–engineered to collaborate with reprogrammed T cells through the efforts of Dr. Crane and her laboratory investigators.
Brain tumors are a frontier for immunotherapy. Now our patients who are benefiting from the leukemia trials are showing us the way to help their peers in the neuro-oncology clinic.
*Thank you so much Dr. Jensen for taking the time to update us on this exciting and hopeful progess. Our gratitude to Dr. Crane and the entire research team at the BTCCCR for moving this work forward.