Furthermore, a combination of USMB and XRT resulted in endothelial cell apoptosis that was confirmed using triple staining of tumour section that included 4′,6-diamidino-2-phenylindole (DAPI) for nuclei, cluster of differentiation 31 (CD31) for viable endothelial cells and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) for detecting DNA fragmentation. This evidence concerns the gene PECAM1 and neoplasm.