VEGFA and neoplasm: ATP might be responsible for several responses that promote tumour progression: (i) induction of a distorted maturation of tumour-associated dendritic cells that would favour a T-helper 2 (Th2) rather than Th1 response; (ii) stimulation of tumour cell proliferation; (iii) potentiation of tumour cell aerobic glycolysis (Warburg effect); (iv) stimulation of release of angiogenic factors (e.g. vascular endothelial growth factor); and (v) generation of the potent immunosuppressor adenosine [44–46].