TOP2B and neoplasm: We used RNA-seq to compare genome-wide gene expression in these PDXs to their patient tumor of origin and the expression profiles were well maintained (r = 0.91, P < 2.2 × 10−16 for SJNBL046; r = 0.75, P < 2.2 × 10−16 for SJNBL047443; Fig. 7D, E); TOP2B expression was also maintained, suggesting these PDXs are a relevant disease model.