TP53 and neoplasm: Going back to the RCAS/TVA system, to address the mechanism by which H3.3K27M increases the proliferation rate of the tumor cells in this model, we performed RNA sequencing (RNAseq) of PDGF-B; H3.3K27M; p53-deficient tumors and PDGF-B; p53-deficient tumors and compared their transcriptome.