Neuroblastoma: Center For Cell And Gene Therapy Trials
Approximately 40% of children with neuroblastoma have "high-risk" tumors with poor survival rates, despite aggressive treatment with combinations of chemotherapy, stem cell transplantation, surgery and radiation therapy. Cases of "high-risk" neuroblastoma are also associated with frequent recurrences and tumors that are resistant to treatment. New therapies are needed for these children to improve the cure rates and reduce the occurrence and severity of the side effects of treatment. The use of immunotherapy for children with neuroblastoma has been an attractive option for treatment, as the immune system provides a way to target tumor cells directly while avoiding the typical side effects of chemotherapy such as hair loss and low blood counts. However, the use of immunotherapy for cancer treatment has been limited in the past by the ability of tumor cells to evade the immune system. Current clinical trials that treat neuroblastoma with antibodies or with immune cells are currently underway at many centers nationwide. Researchers at Texas Children's Hospital and the Center for Cell and Gene Therapy at Baylor College of Medicine have developed novel vaccines that are currently being tested in clinical trials for children with neuroblastoma here in Houston. These vaccines are made from neuroblastoma tumor cells that have been modified to secrete IL-2 and lymphotactin, proteins naturally produced by the body that assist in stimulating the body's own immune system to hunt down and attack the neuroblastoma tumor cells. Treatment with the initial vaccine in earlier studies resulted in responses in almost 40% of patients, with 14% of treated patients having complete responses (Louis and Brenner, 2009). Currently doctors and scientists at Texas Children's are exploring whether a new vaccine combined with daily, low-dose chemotherapy will be more effective in an open clinical trial for neuroblastoma patients called "ATOMIC" (Allogeneic Tumor cell vaccination with Oral Metronomic Cytoxan). Scientists at Texas Children's Hospital are also exploring infusions of modified immune cells in neuroblastoma patients to attack tumor cells directly. T lymphocytes, a type of white blood cell, were modified to express a "CAR" (a Chimeric Antigen Receptor) that recognizes the GD2 marker found on the surfaces of neuroblastoma tumor cells. These T cells were infused into patients with neuroblastoma with clinical responses seen in over 50% of cases. Furthermore, 28% of patients had complete responses to these infused T cells (Louis et al 2011). The successes of these and other immunotherapy clinical trials for children with neuroblastoma provide hope for the routine use of immunotherapy as a part of future standard neuroblastoma treatment. Additional new treatments are currently undergoing testing in the neuroblastoma laboratories at Texas Children's Hospital, and new clinical trials are currently being developed to make these exciting new treatment options available for the children who need them most. Future research by the scientists in the neuroblastoma program at Texas Children's Hospital will continue to explore new pathways, new targets and new treatments in order to provide the most appropriate and most effective therapy for each and every child with neuroblastoma. References: Louis CU and Brenner MK. Cellular Immunotherapy for Neuroblastoma: A Review of Current Vaccine and Adoptive T Cell Therapeutics. Curr Pharm Des 2009; 15: 424-9. Louis CU, Savoldo B, Dotti G, et al. Antitumor Activity and Long-Term Fate of Chimeric Antigen Receptor-Positive T Cells in Patients with Neuroblastoma. Blood 2011; 118: 6050-6.