This impairment of the normal function of vessels leads to an increase in interstitial fluid pressure, which contributes to therapy resistance by inhibiting drug delivery to the tumour.26 In addition, impaired vascular integrity creates hypoxic regions, which induce activation of the transcription factor hypoxia-inducible factor (HIF)-1α, leading to tumour invasion and promotion of angiogenesis.16,27. This evidence concerns the gene HIF1A and neoplasm.