VEGFA and neoplasm: Darbepoetin did not affect the number of tumour microvessels in our model, but, as it served to reduce tumour hypoxia in chemotherapy-treated tumours, downregulation of hypoxia-inducible vascular endothelial growth factor (VEGF) expression and vascular permeability could occur (Shweiki et al, 1992; Dvorak et al, 1999).