Gene expression profiles of primary tumors from patients with metastatic neuroblastoma lacking MYCN amplification. Homo sapiens

Metastatic neuroblastomas lacking amplification of the MYCN proto-oncogene vary in their clinical behavior. Those diagnosed before one year of age are least aggressive and those diagnosed after two years are most aggressive. To improve current risk stratification and gain insight into the biological processes that account for this phenomenon, we analyzed expression profiles from 102 primary untreated neuroblastomas. A 55 gene model classified patients diagnosed after 12 months of age based on molecular risk with an error rate of 17.5%. The progression-free survival for this group was 16% and 79% if their tumors had molecular high or low risk profiles (p<0.001). Expression profiles of tumors with molecular high-risk features included genes relating to regulation of growth and programmed cell death. This series also includes 15 samples obtained at disease relapse. Fourteen out of the fifteen samples had molecular high risk features. Keywords: repeat Overall design: 102 samples obtained at diagnosis were analyzed for model generation and compared to 15 obtained at relapse, using Affymetrix HG-U133A (GPL96) and HG-U133B (GPL97) platforms.