We first utilised these ecotropic MuLE lentiviruses expressing combinations of shRNA or shRNA-miR30 against Cdkn2a, Trp53, Tsc2 and Pten with or without expression of oncogenic HrasG12V, oncogenic PIK3CAH1047R or Myc vectors to attempt to generate panels of genetically-engineered angiosarcoma cell lines by infecting a disease-relevant cell type, namely primary murine endothelial cells from the spleen (pMSECs). This evidence concerns the gene PTEN and angiosarcoma.