Abstract A05: A novel minimal residual disease model of neuroblastoma in mice

Introduction: Despite aggressive medical and surgical therapy, the 5-year survival rate for high-risk neuroblastoma remains poor at 40-50%. The vast majority of these deaths are not due to the primary tumor but from recurrent metastatic disease. However, current in vivo models of neuroblastoma primarily study the efficacy of novel treatments on primary tumor growth (subcutaneous, orthotopic, transgenic) as opposed to residual metastatic disease as seen in patients. We sought to create an in vivo model of minimal residual disease (MRD), which clinically replicates tumor recurrence and metastasis after surgical resection. Methods: We surgically injected one million luciferase expressing human neuroblastoma cells into the left renal capsule of NSG mice to establish tumor xenografts. The neuroblastoma cell lines CHLA-255 (n=10) and CHLA-136 (n=8) were utilized. At day 14, half of CHLA-255 mice (n=5) and CHLA-136 mice (n=4) underwent complete resection of their primary tumors, while the remaining mice underwent a sham surgery. Extent of disease in mice was monitored weekly by bioluminescent imaging. Mice were sacrificed when they met institutional criteria for euthanasia (weakness/paralysis, seizures, inability to eat or drink, moribund state, dyspnea). Survival data was analyzed using Kaplan-Meier method with significance being determined by log-rank test. P