In particular it was shown that cancer stem cells that are found in 3D cultures express not only stemness genes encoding SRY-Box 2: SOX2, Octamer-binding transcription factor 4: OCT-4, or Homeobox transcription factor Nanog, but also pro-angiogenic growth factors like vascular endothelial growth factor: VEGF (Bielecka et al. 2016). Here, VEGFA is linked to cancer.