HIF1A and neoplasm: Besides this, TP53 is able to affect the vascularisation of tumours (Dameron et al, 1994; Semenza, 2001; Mukhopadhyay and Datta, 2004) by regulating the expression of angioregulatory factors (e.g. VEGF, Tsp-1 or Hif-1α) and their receptors in a direct as well as in an indirect manner.