Gene expression-based dissection of inter-histotype, in-tra-histotype and intra-tumor heterogeneity in pediatric tumors

We aimed at assessing the extent of gene expression inter/intra-histotype heterogeneity and ITH in four different pediatric cancer histotypes, analysing multiple samples of each single tumor mass. Based on the availability of clinical, radiological and pathological information, as well as of multiple formalin-fixed, paraffin embedded (FFPE) viable tumor tissue blocksfrom spatially distinct areas of the primary tumor mass, possibly with different morphologies, 5 hepatoblastomas (HB), 5 neuroblastomas (NB), 5 rhabdomyosarcomas (RMS), and 5 Wilms tumors (WT) were selected. Gene expression profiling was performed and Principal Component Analysis (PCA), single sample Hallmark Gene Set (HGS) analysis and Weighted gene co-expression network analysis (WGCNA) were performed