PECAM1 and neoplasm: This relationship was not maintained when comparing expression of human FOXC2-target genes with mouse endothelial genes (Fig 4K), whereas a strong correlation was observed between expression of Pecam1 (murine CD31) and mouse endothelial genes (Fig 4L), robustly validating our endothelial gene signature and species mapping deconvolution of tumor/stroma approach.